Green Stormwater Infrastructure Plan - Sept 2019 ' s
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City of Cupertino
Green Stormwater Infrastructure Plan
Approved on: September 3, 2019
Approved by: The City Council of the City of Cupertino
Submitted by:
City of Cupertino
10300 Torre Avenue
INO
Cupertino, CA 95014 �
In compliance with Provision C.3.j.i.(2) of Order R2-2015-0049
City of Cupertino GSI Plan
ACKNOWLEDGEMENTS
The City of Cupertino gratefully acknowledges the following individuals and organizations that
contributed to this Green Stormwater Infrastructure Plan:
City of Cupertino
Public Works Department
• Roger Lee
• Chad Mosley, P.E.
• Cheri Donnelly
• Alex Wykoff
• Ursula Syrova
EOA, Inc.
• Jill Bicknell, P.E.
• Vishakha Atre
• Liesbeth Magna
The City would like to thank and acknowledge the City of Palo Alto and the City of San Jose for sharing
text from their Green Stormwater Infrastructure Plans.
City of Cupertino GSI Plan
Table of Contents
EXECUTIVESUMMARY..................................................................................................................................1
1. INTRODUCTION.....................................................................................................................................3
1.1 Purpose and Goals of the GSI Plan................................................................................................3
1.2 City Description.............................................................................................................................3
1.2.1 Population Size and Growth..................................................................................................3
1.2.2 City Characteristics................................................................................................................4
1.2.3 Roadways..............................................................................................................................4
1.2.4 Hillsides and Water Resources..............................................................................................5
1.3 Regulatory Context.......................................................................................................................5
1.3.1 Federal and State Regulations and Initiatives.......................................................................5
1.3.2 Municipal Regional Stormwater Permit................................................................................5
1.4 GSI Plan Development Process.....................................................................................................6
1.4.1 GSI Plan Development and Adoption....................................................................................6
1.4.2 Regional Collaboration..........................................................................................................7
1.4.3 Education and Outreach .......................................................................................................7
1.5 GSI Plan Structure and Required Elements...................................................................................8
2. WHAT IS GREEN STORMWATER INFRASTRUCTURE?..........................................................................10
2.1 Green Stormwater Infrastructure...............................................................................................10
2.2 Benefits of Green Stormwater Infrastructure.............................................................................10
2.3 Types of Green Stormwater Infrastructure Facilities..................................................................11
2.3.1 Biotreatment/Bioretention.................................................................................................11
2.3.2 Stormwater Tree Well Filters and Suspended Pavement Systems.....................................12
2.3.3 Pervious Pavement .............................................................................................................13
2.3.4 Infiltration Facilities ............................................................................................................13
2.3.5 Green Roofs.........................................................................................................................14
2.3.6 Rainwater Harvesting and Use............................................................................................14
2.4 Existing GSI Facilities...................................................................................................................14
2.4.1 Stevens Creek Corridor and Creek Restoration project......................................................15
2.4.2 McClellan West Parking Lot................................................................................................16
2.4.3 Apple Park...........................................................................................................................16
3. INTEGRATION WITH OTHER PLANNING DOCUMENTS .......................................................................17
3.1 City Planning Document Review.................................................................................................17
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City of Cupertino GSI Plrn
3.1.1 General Plan—Community Vision 2040..............................................................................17
3.1.2 Pedestrian Transportation Plan ..........................................................................................19
3.1.3 Storm Drain Master Plan.....................................................................................................19
3.1.4 Bicycle Transportation Plan ................................................................................................19
3.1.5 Climate Action Plan.............................................................................................................19
3.1.6 Heart of the City Specific Plan.............................................................................................20
3.1.7 Citywide Parks & Recreation System Master Plan (Draft) ..................................................21
3.1.8 Workplan for Integration of GSI Language into Existing and Future City Planning
Documents..........................................................................................................................................21
3.2 Regional Plans.............................................................................................................................22
3.2.1 Santa Clara Basin Stormwater Resource Plan.....................................................................22
3.2.2 Santa Clara Valley Water District's One Water Plan...........................................................22
3.2.3 Bay Area Integrated Regional Water Management Plan....................................................23
4. GSI DESIGN GUIDELINES, DETAILS, AND SPECIFICATIONS..................................................................24
4.1 Design Guidelines........................................................................................................................24
4.2 Details and Specifications...........................................................................................................24
4.3 Incorporation of SCVURPPP Details and Specifications into City Standards ..............................25
5. GSI PROJECT PRIORITIZATION AND IMPERVIOUS TARGETS...............................................................26
5.1 Project Types...............................................................................................................................26
5.1.1 Early Implementation Projects............................................................................................26
5.1.2 Regulated Projects..............................................................................................................26
5.1.3 LID Projects .........................................................................................................................26
5.1.4 Regional Projects.................................................................................................................27
5.1.5 Green Street Projects..........................................................................................................27
5.2 Identification and Prioritization Process.....................................................................................27
5.2.1 Step 1: Stormwater Resource Plan Prioritization ...............................................................27
5.2.2 Step 2: City-Specific Prioritization.......................................................................................30
5.3 Prioritization Output...................................................................................................................37
6. GSI Implementation Plan ....................................................................................................................39
6.1 City-wide GSI Strategy.................................................................................................................39
6.2 Process for Identifying and Evaluating GSI Project Opportunities .............................................40
6.3 Workplan to Complete Early Implementation Projects..............................................................40
6.4 Legal Mechanisms for GSI Implementation................................................................................41
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6.5 Evaluation of Funding Options....................................................................................................41
6.5.1 Current Funding Sources for GSI Program Elements..........................................................41
6.5.2 Potential Future Funding Options.......................................................................................42
6.6 Impervious Area Targets.............................................................................................................42
6.6.1 Methodology.......................................................................................................................42
6.6.2 Results.................................................................................................................................49
6.7 Project Tracking System..............................................................................................................52
6.7.1 City Project Tracking System (Regulated and GSI)..............................................................52
6.7.2 SCVURPPP Project Tracking System....................................................................................52
TABLES
Table 1-2 Summary of GSI Plan Elements required by Provision C.3.j.i of the MRP. ...................................9
Table 5-1 Screening factors for parcel-based and right-of-way project opportunities..............................29
Table 6-2 Potential GSI Funding Options....................................................................................................43
Table 6-2 Projected cumulative land area (acres) anticipated to be addressed via Green Stormwater
Infrastructure facilities via private redevelopment in the City of Cupertino by 2020, 2030, and 2040.....50
Table 6-3 Actual (2002-2018) and predicted (2019-2040) extent of impervious surface retrofits via GSI
implementation on privately-and publicly-owned parcels in the City of Cupertino by 2020, 2030, and
2040. ...........................................................................................................................................................51
FIGURES
Figure 2-1 Stormwater curb extension, Southgate Neighborhood, Palo Alto (Source: EOA).....................11
Figure 2-2 Stormwater planter, Hacienda Avenue, Campbell (Source: City of Campbell).........................12
Figure 2-3 Stormwater tree well filter conceptual examples: modular suspended pavement system (left),
column suspended pavement system (right). (Courtesy of Philadelphia Water Department)..................12
Figure 2-4 Permeable interlocking concrete pavers, Mayfield Playing Fields, Palo Alto (Source: EOA) ....13
Figure 2-5 Infiltration trench, San Jose (Source: City of San Jose)..............................................................13
Figure 2-6 Subsurface infiltration system (Source: Conteches.com)..........................................................13
Figure 2-7 Green roof at Fourth Street Apartments, San Jose (Source: EOA)............................................14
Figure 2-8 Rainwater harvesting cistern, Environmental Innovation Center,San Jose (Source: City of San
Jose) ............................................................................................................................................................14
Figure 2-9 Subsurface vault, under construction (Source: Conteches.com) ..............................................14
Figure 2-10 Completed green parking bays (above left) and parking bays under construction, showing
the recycled plastic geocells that support vehicle weight(above right).(Source: City of Cupertino) ........15
Figure 2-11 Pervious concrete bike path and walkway at Blackberry Farm. (Source: City of Cupertino)..15
Figure 5-1 City of Cupertino Public Parcels and Street Segments with Opportunities for GSI (Source: EOA,
and Santa Clara Basin Stormwater Resource Plan, 2018)...........................................................................31
Figure 5-2. City of Cupertino Special Project Areas and Priority Development Area (Source: City of
CupertinoGeneral Plan)..............................................................................................................................33
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Figure 5-3. City of Cupertino Public Projects with Potential for GSI (Source: City of Cupertino FY 17-18
Annual Report, and 2018 Santa Clara Basin Stormwater Resource Plan) ..................................................36
Figure 5-5 City of Cupertino GSI Overview.................................................................................................38
Figure 6-1 Existing and projected cumulative land area (acres) anticipated to be addressed via Green
Stormwater Infrastructure facilities installed via private redevelopment in the City of Cupertino by 2020,
2030, and 2040. ..........................................................................................................................................49
APPENDICES
Appendix A Prioritization Metrics for Scoring GSI Project Opportunities
Appendix B Street Segments and Parcels in Cupertino with Opportunities for GSI
Appendix C GSI concept for the Mary Avenue Greenbelt and Trail Project
Appendix D Guidance for Identifying Green Infrastructure Potential in Municipal Capital Improvement
Plan Projects
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LIST OF ACRONYMS
ABAG Association of Bay Area Governments
BASMAA Bay Area Stormwater Management Agencies Association
Caltrans California Department of Transportation
CFD Community Facilities District
CIP Capital Improvement Program
DOF Department of Finance
EPA United States Environmental Protection Agency
FY Fiscal Year
GI Green Infrastructure
GIS Geographic Information System
GSI Green Stormwater Infrastructure
IRWMP Integrated Regional Water Management Plan
LID Low Impact Development
MRP Municipal Regional Stormwater NPDES Permit
MS4 Municipal Separate Storm Sewer System
NPDES National Pollutant Discharge Elimination System
NRCS National Resource Conservation Service
O&M Operation and Maintenance
PDA Priority Development Area
PICP Permeable Interlocking Concrete Pavers
PP Permeable Pavers
SCVURPPP Santa Clara Valley Urban Runoff Pollution Prevention Program
State Water Board State Water Resource Control Board
STORMS Strategy to Optimize Resource Management of Stormwater
SWRP Storm Water Resource Plan
Valley Water Santa Clara Valley Water District
Regional Water Board San Francisco Bay Regional Water Quality Control Board
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EXECUTIVE SUMMARY
Development of this Green Stormwater Infrastructure (GSI) Plan is required by the City's Municipal
Regional Stormwater National Pollutant Discharge Elimination System (NPDES) Permit. Urban
development has traditionally involved replacing natural landscapes with solid pavements and buildings,
using underground metal-pipe storm drainage systems to carry increased amounts of stormwater runoff
and pollutants directly into local creeks, which empty into San Francisco Bay. To reduce the impact of
urban development on waterways, Bay Area municipalities are required to begin augmenting traditional
stormwater drainage systems with Green Stormwater Infrastructure (GSI)treatments.
GSI features mimic nature, and use plants, soils, and/or pervious surfaces to collect stormwater, allowing
it to soak into the ground and be filtered by the soil. This reduces the quantity of water and pollutants
flowing directly into local creeks. The City began the process of incorporating GSI into public projects in
2014, with the completion of the 18-acre Stevens Creek Corridor Park and Restoration.
The City of Cupertino has prepared this GSI Plan, specifically in accordance with its MRP requirements,to
guide the siting, implementation,tracking, and reporting of GSI projects on City-owned land, including the
public right of way, over the next several decades (2020—2040).
Cupertino's GSI Plan describes the City's approach to identifying and prioritizing potential areas for
implementing GSI,and estimating targets for the City's area that could be addressed by GSI through 2040.
The Plan lays out the City's GSI implementation strategy and includes maps of the City's prioritized areas
and potential project opportunities. Key elements of the strategy include: coordination with State-
mandated GSI requirements for private development and opportunities in adjacent public rights-of-way;
identification of GSI opportunities in capital projects; and aligning GSI goals and policies with other City
planning documents to achieve multiple benefits and provide safer, sustainable, and attractive public
streetscapes. The Plan contains guidance and standards for GSI project design and construction, and
describes how the City will track and map constructed GSI projects and make the information available to
the public. Lastly, it explains existing legal mechanisms to implement the GSI Plan,and identifies potential
sources of funding for the design, construction, and maintenance of GSI projects.
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1. INTRODUCTION
Urban development has traditionally involved replacing natural landscapes with solid pavements and
buildings, and using storm drain systems to carry increased amounts of stormwater runoff and
pollutants directly into local streams. Green stormwater infrastructure (GSI), however, uses plants and
soils to mimic natural watershed processes, capture stormwater and create healthier environments. Bay
Area cities and counties are required by State and regional regulatory agencies to move from traditional
(grey) stormwater conveyance systems to GSI systems over time.This GSI Plan serves as an
implementation guide for the City of Cupertino (City)to incorporate GSI into storm drain infrastructure
on public and private lands where feasible over the next several decades.
1.1 Purpose and Goals of the GSI Plan
The purpose of the City's GSI Plan is to demonstrate the City's commitment to gradually transform its
traditional storm drainage infrastructure to green stormwater infrastructure.The GSI Plan will guide the
identification, implementation,tracking, and reporting of green stormwater infrastructure projects
within the City.The GSI Plan will be coordinated with other City plans, such as the General Plan,the
Climate Action Plan, the Bicycle Transportation Plan, the Pedestrian Transportation Plan, and other
specific and master plans,to achieve multiple potential benefits to the community, including improved
water and air quality, reduced local flooding, increased water supply,traffic calming, safer pedestrian
and bicycle facilities, climate resiliency, improved wildlife habitat, and a more pleasant urban
environment.
Specific goals of the GSI Plan are to:
• Align the City's goals, policies and implementation strategies for GSI with the General Plan and
other related planning documents;
• Identify and prioritize GSI opportunities throughout the City;
• Establish targets for the extent of City area to be addressed by GSI over certain timeframes;
• Provide a workplan and legal and funding mechanisms to implement prioritized projects; and
• Establish a process for tracking, mapping, and reporting completed projects
1.2 City Description
Incorporated in 1955,the City of Cupertino is located in Santa Clara County, on the western edge of
Silicon Valley against the foothills of the Santa Cruz Mountains. It has a jurisdictional area of 7,235 acres
(11.3 square miles).
1.2.1 Population Size and Growth
According to the General Plan, "Community Vision 2040", Cupertino's population grew from 3,664 in
1960 to over 50,500 in 2000. Most of the population growth was from tract development during the
1970s and 1980s and annexation of unincorporated County land. Between 2000 and 2010 the City of
Cupertino's population increased by 15.3 percent,from 50,546 (18,204 households)to 58,302 persons
(20,181 households),with a population density of 5,179 people per square mile and average household
size of 2.87. A portion of this population growth can be attributed to the City's annexation of 168 acres
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City of Cupertino GSI Plan
of land between 2000 and 2008. As of 2019 according to the California Department of Finance (DOF)1,
the estimated population is 59,879.The City's population is projected to grow to 66,110 by 2040 (Plan
Bay Area, 2013), which is approximately a 12% increase over 30 years.
1.2.2 City Characteristics
Cupertino's land use pattern was largely built on a conventional suburban model,with predominantly
single-family residential subdivisions and distinct commercial and employment centers.This
development pattern was also heavily influenced by the topography of the area, with more intensive
growth located on the valley floor and lower design residential on the foothills.The western area by the
foothills is semi-rural with steep terrain, larger residential lots and access to open space.The pattern
becomes more suburban immediately west of Highway 85 where residential neighborhoods have a
more uniform pattern with smaller lots and older commercial and industrial areas along Stevens Creek
Boulevard and Bubb Road.The land use pattern becomes more urban east of Highway 85, with a
relatively connected street grid and commercial development along major boulevards such as Stevens
Creek, De Anza, Homestead, Stelling and Wolfe.This area also has significant amounts of multi-family
development in and around the major boulevards.
The suburban pattern is also reflected in building locations, with most of the older buildings set back
from the street with parking lots in the front. Streets have also been historically widened to
accommodate larger volumes of traffic, often to the detriment of other forms of transportation such as
walking, biking and transit.According to the 2015 General Plan Land Use Element,the City has made
strides in the last 20 years towards improving walkability and bikeability by retrofitting existing streets
to include bike lanes; creating sidewalks lined with trees along major boulevards; and encouraging
development to provide a more pedestrian-oriented frontage with active uses, gathering places and
entries lining the street.
1.2.3 Roadways
The City is defined by its four major roadways: Homestead Road,Wolfe Road, De Anza Boulevard and
Stevens Creek Boulevard.These major mixed-use corridors have been the center of retail, commercial,
office and multi-family housing in Cupertino for decades.
Common residential street widths range from 20 feet (for streets with no street parking) to 36 feet (for
those with parking on both sides). Developers are typically required to install curb,gutters, and
sidewalks.The City prefers detached sidewalks with a landscaped buffer in between the street and the
pedestrian walk to enhance community aesthetics and improve pedestrian safety.
Two state highways traverse Cupertino.The City is linked to the cities of San Francisco and San Jose by
Interstate Highway 280 which runs along most of the its northern border.State Route 85, which runs
from Mountain View to South San Jose, cuts diagonally across the City at its northwest boundary to its
southeast boundary. All state highways are owned and maintained by the California Department of
Transportation (Caltrans).
1 Source:State of California, Department of Finance,E-1 Population Estimates for Cities,Counties and the State with Annual
Percent Change—January 1,2018 and 2011.Sacramento,California, May 2019.Online at
http://www.dof.ca.gov/Forecasting/Demographics/Estimates/E-1/.
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City of Cupertino GSI Plan
The City has approximately 1.5 miles of rural road in the residential hillside area.
1.2.4 Hillsides and Water Resources
Cupertino's hillsides are an irreplaceable resource shared by the entire Santa Clara Valley.They provide
important habitat for plants and wildlife; watershed capacity to prevent flooding in downstream areas; a
wide vegetative belt that cleanses the air of pollutants; and a natural environment that provides a
contrast to the built environment. Significant water bodies and water sources within Cupertino are:
• Stevens Creek
• Permanente Creek
• Regnart Creek
• Heney Creek
• Calabazas Creek
1.3 Regulatory Context
1.3.1 Federal and State Regulations and Initiatives
The U.S. Environmental Protection Agency(EPA) has authority under the Clean Water Act to promulgate
and enforce stormwater related regulations. For the State of California, EPA has delegated the
regulatory authority to the State Water Resources Control Board (State Water Board), which in turn, has
delegated authority to the San Francisco Bay Regional Water Quality Control Board (Regional Water
Board)to issue National Pollutant Discharge Elimination System (NPDES) permits in the San Francisco
Bay Region. Stormwater NPDES permits allow stormwater discharges from municipal separate storm
sewer systems (MS4s)to local creeks, San Francisco Bay, and other water bodies as long as they do not
adversely affect the beneficial uses of or exceed any applicable water quality standards for those waters.
Since the early 2000's,the EPA has recognized and promoted the benefits of using GSI in protecting
drinking water supplies and public health, mitigating overflows from combined and separate storm
sewers and reducing stormwater pollution, and it has encouraged the use of GSI by municipal agencies
as a prominent component of their MS4 programs.
The State and Regional Water Boards have followed suit in recognizing not only the water quality
benefits of GSI but the opportunity to augment local water supplies in response to the impacts of
drought and climate change as well.The 2014 California Water Action Plan called for multiple benefit
stormwater management solutions and more efficient permitting programs.This directive created the
State Water Board's "Strategy to Optimize Resource Management of Stormwater" (STORMS). STORMS'
stated mission is to "lead the evolution of storm water management in California by advancing the
perspective that storm water is a valuable resource, supporting policies for collaborative watershed-
level storm water management and pollution prevention, removing obstacles to funding, developing
resources, and integrating regulatory and non-regulatory interests."
These Federal and State initiatives have influenced approaches in Bay Area municipal stormwater NPDES
permits, as described in Section 1.3.2.
1.3.2 Municipal Regional Stormwater Permit
The City is subject to the requirements of the Municipal Regional Stormwater NPDES Permit(MRP)for
Phase I municipalities and agencies in the San Francisco Bay area (Order 112-2015-0049), which became
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City of Cupertino GSI Plan
effective on January 1, 2016.The MRP applies to 76 municipalities and flood control agencies that
discharge stormwater to San Francisco Bay, collectively referred to as permittees.
Over the last 13 years, under Provision C.3 of the MRP and previous permits, new development and
redevelopment projects on private and public property that exceed certain size thresholds ("regulated
projects") have been required to mitigate impacts on water quality by incorporating "Low Impact
Development" (LID) measures, including site design, pollutant source control, stormwater treatment
and flow control measures as appropriate. LID treatment measures, such as rainwater harvesting and
use, infiltration, and biotreatment, have been required on most regulated projects since December
2011.
Provision C.3.j of the 2016 MRP requires the City to develop and implement a long-term GSI Plant for
the inclusion of LID measures into storm drain infrastructure on public and private lands, including
streets, roads, storm drains, parking lots, building roofs, and other elements.The GSI Plan must be
completed and submitted to the Regional Water Board by September 30, 2019.
While Provision C.3.j of the MRP contains the GSI program planning and analysis requirements, other
provisions (C.11 and C.12) establish a linkage between public and private GSI features and required
reductions of pollutants in stormwater discharges. Permittees in Santa Clara County(County),
collectively, must implement GSI on public and private property to achieve specified pollutant load
reduction goals by the years 2020, 2030, and 2040.These efforts will be integrated and coordinated
countywide for the most effective and resource-efficient program. As an indication as to whether these
load reductions will be met, Permittees must include in their GSI Plans estimated "targets"for the
amounts of impervious surface to be "retrofitted" as part of public and private projects (i.e.,
redeveloped or changed such that runoff from those surfaces will be captured in a stormwater
treatment system or GSI measure) over the same timeframes(2020, 2030, and 2040).
A key part of the GSI definition in the MRP is the inclusion of GSI systems at both private and public
property locations.This has been done in order to plan, analyze, implement and credit GSI systems for
pollutant load reductions on a watershed scale, as well as recognize all GSI accomplishments within a
municipality.The focus of the GSI Plan is the integration of GSI systems into public buildings, parks,
parking lots, and rights-of-way(e.g. road or bike path). However,the GSI Plan may also establish
opportunities to include GSI facilities at private properties or in conjunction with private development,
so they can contribute to meeting the target load reductions on a county-wide level as well as
implement GSI on a larger scale.
1.4 GSI Plan Development Process
1.4.1 GSI Plan Development and Adoption
The GSI Plan development process began with the preparation of the City's GSI Plan Framework
(Framework), a work plan describing the goals, approach, tasks, and schedule needed to complete the
GSI Plan. Development of the Framework was a regulatory requirement (Provision C.3.j.i(1) of the MRP)
z Although the MRP uses the term green infrastructure(GI),the agencies within Santa Clara County, including the
City of Cupertino, prefer to use the term green stormwater infrastructure(GSI). Therefore,the term GSI is used in
this document.
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City of Cupertino GSI Plan
to demonstrate the City's commitment to completing the GSI Plan by September 30, 2019.The City
completed the Framework and City Council approved it on April 18, 2017.
The City established a GSI Work Group, consisting of staff from the City's Public Works and Planning
Departments.The GSI Work Group worked with a consultant team to develop the GSI Plan. Staff
attended the Sustainability Commission on March 16, 2017 where SFEI's (San Francisco Estuary
Institute) Robin Grossinger gave a presentation on healthier landscapes for people in nature (GSI
concepts). City staff followed with an overview of the GSI Framework that City staff was in the process
of developing. More recently, an overview of the MRP requirements and summary of the proposed
Plan was presented to City Council on July 16, 2019. GSI presentations for soliciting comments and
feedback were given to the Planning Commission on August 13, 2019 and the Sustainability Commission
on August 15, 2019. The final GSI Plan was adopted by the City Council on September 3, 2019.
1.4.2 Regional Collaboration
The City is a member of the Santa Clara Valley Urban Runoff Pollution Prevention Program (SCVURPPP),
an association of thirteen cities and towns in the Santa Clara Valley,the County of Santa Clara, and the
Santa Clara Valley Water District (Valley Water)that collaborate on stormwater regulatory activities and
compliance.The City's GSI Plan was developed in collaboration with SCVURPPP; SCVURPPP input
included technical guidance,templates, and completion of certain GSI Plan elements at the countywide
level. SCVURPPP guidance and products are discussed in more detail in relevant sections of the GSI Plan.
The City,via SCVURPPP, also coordinated with the Bay Area Stormwater Management Agencies
Association (BASMAA) on regional GSI guidance and received feedback through BASMAA from MRP
regulators on GSI expectations and approaches. BASMAA members include other countywide
stormwater programs in Alameda, Contra Costa, and San Mateo Counties, and area-wide programs in
the Vallejo and Fairfield-Suisun portions of Solano County, whose participating municipalities are
permittees under the MRP.
1.4.3 Education and Outreach
One of the first and most important steps in the development of the GSI Plan is educating a
municipality's department staff, managers, and elected officials about the purposes and goals of green
infrastructure,the required elements of the GSI Plan, and steps needed to develop and implement the
GSI Plan, and get their support and commitment to the Plan and this new approach to urban
infrastructure.Another important first step is local community and stakeholder outreach to gain public
support.The City of Cupertino began this process in FY 15-16 and FY 16-17 and completed the following
tasks:
• Convened 3-4 interdepartmental meetings with Public Works, GIS, Capital Improvement
Program (CIP), and Environmental staff and management to discuss GSI requirements and
assigned tasks.
• Discussed with appropriate department staff the MRP requirements to analyze proposed
capital projects for opportunities to incorporate GSI and completed the first list of planned
and potential GSI projects.
• Provided training to department staff on GSI requirements and strategies via presentations
and workshops.
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City of Cupertino GSI Plan
• Invited elected officials to a SCVURPPP Green Infrastructure presentation to raise awareness
of the goals and requirements in the MRP and the concepts, intent and multiple benefits of
GSI.
• At the suggestion of the Vice Mayor,the Sustainability Commission invited guest speaker
Robin Grossinger, a scientist from San Francisco Estuary Institute (SFEI),to give his
presentation on the vision for a resilient Silicon Valley landscape'.
• Public Works Environmental staff participated in the Green Infrastructure Leadership
Conversation and the Regional Roundtable on Sustainable Streets
Public and stakeholder support is also essential for the successful implementation of the GSI Plan and
future GSI projects.To this end, the City has coordinated with SCVURPPP and the Watershed Education
and Outreach subgroup on a comprehensive outreach and education program. Key audiences include:
the general public (countywide, and in the neighborhood or municipality where GSI projects are
located);the development community (e.g., developers, engineers, landscape architects, and
contractors); and elected officials.The GSI outreach and education program includes a GSI website4,
public presentations, and radio and online advertising to promote GSI features.The City of Cupertino
will conduct or continue to conduct education and outreach activities as part of development of the GSI
Plan and seek community input as specific projects are designed and constructed.
1.5 GSI Plan Structure and Required Elements
The remainder of the GSI Plan is structured as follows:
Chapter 2 describes the definition, purpose, and benefits of GSI, and describes the different types of GSI
facilities.
Chapter 3 describes the relationship of the GSI Plan to other planning documents and how those
planning documents have been updated or modified, if needed,to support and incorporate GSI
requirements. For documents whose desired updates and modifications have not been accomplished by
the completion of the GSI Plan, a work plan and schedule are laid out to complete them.
Chapter 4 outlines the materials being developed by SCVURPPP and the City to provide guidelines,
typical details, specifications and standards for municipal staff and others in the design, construction,
and operation and maintenance of GSI measures.
Chapter 5 presents information on the different types of GSI projects and the methodology and results
for identifying and prioritizing areas for potential GSI projects.
Chapter 6 outlines the City's strategy for implementing potential GSI projects within the next ten years
and through 2040, discusses the variety of mechanisms to be employed by the City in order to
'SFEI's recommendations for a more sustainable South Bay looks at what the City can do to integrate resilient
landscape within the reality of new and re-development. From a practical perspective, the City of Cupertino can
consider actions over the course of the next generations to improve the ecology of the area and how it can work
with larger developments to incorporate these types of principles in its planning.
4 httP://www.mywatershedwatch.org/residents/green-streets/
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City of Cupertino GSI Plan
implement the GSI Plan, and presents the estimated targets for the amounts of impervious surface to be
"retrofitted" as part of public and private projects by 2020, 2030, and 2040.
The GSI Plan elements required by Provision C.3.j.i.(2) of the MRP and the section of the document in
which each component can be found are summarized in Table 1-2 below.
Table 1-1 Summary of GSI Plan Elements required by Provision C.3.j.i of the MRP.
MRP Provision GSI Plan Elements GSI Plan Section
C.3.j.i.(2)(a) Project Identification and Prioritization Mechanism Chapter 5
C.3.j.i.(2)(b) Prioritized Project Locations Section 5.3
C.3.j.i.(2)(c) Impervious Surface Targets Section 6.6
C.3.j.i.(2)(d) Completed Project Tracking System Section 6.7
C.3.j.i.(2)(e,f) Guidelines and Specifications Chapter 4
C.3.j.i.(2)(g) Alternative Sizing Requirements for Green Street Projects Section 4.1
C.3.j.i.(2)(h,i) Integration with Other Municipal Plans Chapter 3
C.3.j.i.(2)(i) Workplan for Integration of GSI Language into City Planning
Section 3.1.8
Documents
C.3.j.i.(2)(j) Workplan to Complete C.3.j. Early Implementation Projects Section 6.3
C.3.j.i.(2)(k) Evaluation of Funding Options Section 6.5
C.3.j.i.(3) Legal and Implementation Mechanisms Section 6.4
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City of Cupertino GSI Plan
2. WHAT IS GREEN STORMWATER INFRASTRUCTURE?
In natural landscapes, most of the rainwater soaks into the soil or is taken up by plants and
trees. However, in urban areas, building footprints and paved surfaces such as driveways, sidewalks, and
streets prevent rain from soaking into the ground. As rainwater flows over and runs off these impervious
surfaces, this "urban runoff" or "stormwater runoff" can pick up pollutants such as motor oil, metals,
pesticides, sediment, pet waste, and litter. It then carries these pollutants into the City's storm drains,
which flow directly to local creeks and San Francisco Bay, without any cleaning or filtering to remove
pollutants. Stormwater runoff is therefore a major contributor to water pollution in urban areas.
As urban areas develop,the increase in impervious surface also results in increases in peak flows and
volumes of stormwater runoff from rain events.Traditional "gray" stormwater infrastructure, like most
of the City's storm drain system, is designed to convey stormwater flows quickly away from urban areas.
However,the increased peak flows and volumes can cause erosion, flooding, and habitat degradation in
downstream creeks to which stormwater is discharged, damaging habitat, property, and infrastructure.
2.1 Green Stormwater Infrastructure
A new approach to managing stormwater is to implement green stormwater infrastructure. GSI uses
vegetation, soils, and other elements and practices to capture,treat, infiltrate and slow urban runoff
and thereby restore some of the natural processes required to manage water and create healthier urban
environments. GSI facilities can also be designed to capture stormwater for uses such as irrigation and
toilet flushing.
GSI integrates building and roadway design, complete streets, drainage infrastructure, urban forestry,
soil conservation and sustainable landscaping practices to achieve multiple benefits. At the city or
county scale, GSI is a patchwork of natural areas that provides habitat,flood protection, cleaner air, and
cleaner water.At the neighborhood or site scale, GSI comprises stormwater management systems that
mimic nature and soak up and store water.'
2.2 Benefits of Green Stormwater Infrastructure
GSI can provide multiple benefits beyond just managing rainfall and runoff.These benefits include
environmental, economic, and social improvements.
GSI measures can mitigate localized flooding and reduce erosive flows and quantities of pollutants being
discharged to local creeks and the San Francisco Bay.Vegetated GSI systems can beautify public places
and help improve air quality by filtering and removing airborne contaminants from vehicle and industrial
sources.They can also reduce urban heat island effects by providing shade and absorbing heat better
than paved surfaces, and provide habitat for birds, butterflies, bees, and other local species. When GSI
facilities are integrated into traffic calming improvements such as curb extensions and bulb-outs at
intersections,they can help increase pedestrian and bicycle safety and promote active transportation,
which in turn can result in improved human health.
'https://www.epa.gov/green-infrastructure/what-green-infrastructure
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City of Cupertino GSI Plan
GSI facilities designed with extra storage can capture stormwater for later use as irrigation water or non-
potable uses such as toilet flushing and cooling tower supply,thus conserving potable water supplies.
Widespread implementation of GSI potentially offers significant economic benefits, such as deferring or
eliminating the need for some gray infrastructure projects. By providing more storage within the
watershed, GSI can help reduce the costs of conveyance and pumping of stormwater. When cost-benefit
analyses are performed, GSI is often the preferred alternative due to the multiple benefits provided by
GSI as compared to conventional infrastructure.
2.3 Types of Green Stormwater Infrastructure Facilities
Integrating GSI into public spaces typically involves construction of stormwater capture and treatment
measures in public streets, parks, and parking lots or as part of public buildings.Types of GSI measures
that can be constructed in public spaces include: (1) bioretention; (2) stormwater tree well filters; (3)
pervious pavement, (4) infiltration facilities, (5) green roofs, and 6) rainwater harvesting and use
facilities. A description of these facility types is provided below.
2.3.1 Biotreatment/Bioretention
Bioretention areas are depressed landscaped
areas that consist of a ponding area, mulch
layer, plants, and a special biotreatment soil
media composed of sand and compost, din
underlain by drain rock and an underdrain if � ' �� � b
required. Bioretention is designed to retain
I r� .<
stormwater runoff,filter stormwater runoff
through biotreatment soil media and plant
roots, and either infiltrate stormwater runoff
to underlying soils as allowed by site
conditions, or release treated stormwater Figure 2-1 Stormwater curb extension,Southgate Neighborhood,
runoff to the storm drain system, or both. Palo Alto(Source:EOA)
They can be of any shape and are adaptable
for use on a building or parking lot site or in the street right-of-way.
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City of Cupertino GSI Plan
Bioretention systems in the streetscape have specific names: stormwater
planters, stormwater curb extensions (or bulb-outs), and stormwater tree well
filters (described in the next section). - - -
A stormwater curb extension (Figure 2-1) is a bioretention system that extends -
into the roadway and involves modification of the curb line and gutter.
Stormwater curb extensions may be installed midblock or at an intersection.
Curb bulb-outs and curb extensions installed for pedestrian safety,traffic
calming, and other transportation benefits can also provide opportunities for
siting bioretention facilities.
A stormwater planter is a linear bioretention facility in the public right-of-way
along the edge of the street, often in the planter strip between the street and
sidewalk.They are typically designed with vertical (concrete) sides. However, as
shown in Figure 2-2, they can also have sloped sides depending on the amount
of space that is available. Figure 2-2 Stormwater planter,
Hacienda Avenue, Campbell
2.3.2 Stormwater Tree Well Filters and Suspended Pavement Systems (Source:City of Campbell)
A stormwater tree well filter is a type of bioretention system consisting of an
excavated pit or vault that is filled with biotreatment soil media, planted with a tree and other
vegetation, and underlain with drain rock and an underdrain, if needed. Stormwater tree well filters can
be constructed in series and linked via a subsurface trench or underdrain.A Stormwater tree well filter
can require less dedicated space than other types of bioretention areas.
Suspended pavement systems may be used to provide increased underground treatment area and soil
volume for tree well filters.These are structural systems designed to provide support for pavement while
preserving large volumes of uncompacted soil for tree roots. Suspended pavement systems may be any
engineered system of structural supports or commercially available proprietary structural systems.
Stormwater tree well filters and suspended pavements systems are especially useful in settings between
existing sidewalk elements where available space is at a premium.They can also be used in curb
extensions or bulb-outs, medians, or parking lots if surrounding grades allow for drainage to those areas.
The systems can be designed to receive runoff through curb cuts or catch basins or allow runoff to enter
through pervious pavers on top of the structural support.
i
Figure 2-3 Stormwater tree well filter conceptual examples:modular suspended pavement system(left),column
suspended pavement system(right). (Courtesy of Philadelphia Water Department)
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City of Cupertino GSI Plan
2.3.3 Pervious Pavement
Pervious pavement is hardscape that allows water to pass through its surface into a storage area filled
with gravel prior to infiltrating into underlying soils.Types of pervious pavement include permeable
interlocking concrete pavers, pervious concrete, porous asphalt, and grid pavement. Pervious pavement
is often used in parking areas or on streets where
bioretention is not feasible due to space constraints or if a ,
there is a need to maintain parking. Pervious pavement
does not require a dedicated surface area for treatment
and allows a site to maintain its existing hardscape. — -
There are two types of pervious pavers: Permeable
Interlocking Concrete Pavers (PICP) and Permeable Pavers
(PP). PICP allows water to pass through the joint spacing -
between solid pavers, and PP allows water to pass through
the paver itself and therefore can have tighter joints. Figure 2-4 Permeable interlocking concrete
Porous asphalt and pervious concrete are similar to pavers,Mayfield Playing Fields,Palo Alto
traditional asphalt and concrete, but do not include fine (Source:EOA)
aggregates in the mixture, allowing water to pass through the surface. All types are supported by several
layers of different sizes of gravel to provide structural support and water storage.
2.3.4 Infiltration Facilities
Where soil conditions permit, infiltration facilities can be used
to capture stormwater and infiltrate it into native soils. The
two primary types are infiltration trenches and subsurface
infiltration systems.
An infiltration trench is an excavated trench backfilled with a
stone aggregate and lined with a filter fabric. Infiltration
trenches collect and detain runoff, store it in the void spaces
of the aggregate, and allow it to infiltrate into the underlying
soil. Infiltration trenches can be used along roadways,
alleyways, and the edges or medians of parking lots. An Figure 2-5 Infiltration trench,San Jose
example of an infiltration trench is shown in Figure 2-5. (Source:City of San Jose)
Subsurface infiltration systems are another type of GSI
measure that may be used beneath parking lots or parks to
infiltrate larger quantities of runoff.These systems,also knowni��f�
as infiltration galleries, are underground vaults or pipes that
store and infiltrate stormwater while preserving the uses of the
land surface above parking lots, parks and playing fields. An
example is shown in Figure 2-6. Storage can take the form of
large-diameter perforated metal or plastic pipe, or concrete Figure 2-6 Subsurface infiltration"system
arches, concrete vaults, plastic chambers or crates with open (Source:Conteches.com)
bottoms. Prefabricated, modular infiltration galleries are
available in a variety of shapes,sizes,and material types that are
strong enough for heavy vehicle loads.
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City of Cupertino GSI Plan
2.3.5 Green Roofs
Green roofs are vegetated roof systems that filter, absorb,
and retain or detain the rain that falls upon them. Green roof
systems are comprised of a layer of planting media planted _
with vegetation, underlain by other structural components
including waterproof membranes, synthetic insulation,
geofabrics, and underdrains. A green roof can be either �-
"extensive", with 3 to 7 inches of lightweight planting media
and low-profile, low-maintenance plants, or"intensive", with
a thicker(8 to 48 inches) of media, more varied plantings, and
a more garden-like appearance. Green roofs can provide high Figure 2-7 Green roof at Fourth Street
rates of rainfall retention via plant uptake and Apartments,San Jose(Source:EOA)
evapotranspiration and can decrease peak flow rates in storm
drain systems because of the storage that occurs in the planting media during rain events.
2.3.6 Rainwater Harvesting and Use
Rainwater harvesting is the process of collecting rainwater from
impervious surfaces and storing it for later use. Storage facilities that
can be used to capture stormwater include rain barrels, above-ground
or below-ground cisterns (Figure 2-8), open storage reservoirs(e.g.,
ponds), and various underground storage devices (tanks,vaults, pipes,
and proprietary storage systems)(Figure 2-9).The captured water is
then fed into irrigation systems or non-potable water plumbing
systems, either by pumping or by gravity flow. Uses of captured water
may include irrigation,vehicle washing, and indoor non-potable use Figure 2-8 Rainwater harvesting cistern,
such as toilet flushing, heating and cooling, or industrial processing. Environmental Innovation Center,San
lose(Source:City of San Jose)
The two most common applications of rainwater harvesting are 1)
collection of roof runoff from buildings; and 2) collection of runoff from
at-grade surfaces or diversion of water from storm drains into large
underground storage facilities below parking lots or parks. Rooftop _
runoff usually contains lower quantities of pollutants than at-grade
surface runoff and can be collected via gravity flow. Underground
storage systems typically include pre-treatment facilities to remove
pollutants from stormwater prior to storage and use. Figure 2-9 Subsurface vault,under
2.4 Existing GSI Facilities construction(Source:Conteches.com)
The City of Cupertino completed an 18-acre Stevens Creek Corridor
Park and Restoration project in July 2014.The City is also installing GSI measures at the McClellan Ranch
Preserve as part of expansion and improvements at the site,with construction expected to be
completed by September 1, 2019. GSI projects such as this, completed by the City prior to or during the
current permit term (2016-2020), are also referred to in the permit as "Early Implementation" projects
(see Section 5.1.1 of this GSI Plan). Both projects are described below. A description of the Apple Park
project, which included GSI improvements in the public right-of-way, is also described below.
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City of Cupertino GSI Plan
2.4.1 Stevens Creek Corridor and Creek Restoration project
The Stevens Creek Corridor and Creek Restoration project at Blackberry Farm in Cupertino consisted of
two phases.
Phase 1 of the project restored a portion of Stevens Creek, enhanced natural hydrologic processes, and
improved wildlife and habitat values. Impervious cover was reduced by 3.4 acres, including removal of
an asphalt driveway and parking lot, and concrete surfaces in the creek corridor.The former parking lot,
which drained directly into the creek, was replaced by a smaller green parking area, set back from the
creek and made entirely of permeable material. Drive aisles are made of porous concrete that is colored
to reduce heat gain. Parking bays were constructed using recycled plastic geocells to support vehicle
weight filled with special soil and planted with turf grass (see Figure 2-10). During heavy rains, excess
water flows to bioretention areas in a center median. Dozens of native trees were also planted.The
design aimed to use all rain and storm flows to water native plantings.The project site is located within
a flood plain. It was designed to accommodate being submerged during unusually high creek flows
without damage to new infrastructure,water quality or wildlife and to retain stormwater onsite.The
design enables the site's ability to attenuate flooding, and naturally filter and return rainfall and runoff
from the site to groundwater.
Figure 2-10 Completed green parking bays(above left)and parking bays under construction,showing the
ecycled plastic geocells that support vehicle weight(above right).(Source:City of Cupertino)
Phase 2 of the Stevens Creek Corridor project included four
new bioswales and an infiltration area installed on the
adjacent golf course to capture and infiltrate runoff from
the golf course, buildings, and the parking lot that
previously flowed directly into the creek.Additionally, an ....
all-weather trail was installed using pervious concrete r'
(Figure 2-11).The trail material is compatible with
floodplain standards and protects the fishery and wildlife. r
Figure 2-11 Pervious concrete bike
path and walkway at Blackberry
Farm. (Source:City of Cupertino)
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City of Cupertino GSI Plan
2.4.2 McClellan West Parking Lot
McClellan Ranch Preserve overflow parking had historically been relegated to the 1.4 acre vacant
unimproved parcel which lies west of the Preserve and adjacent to Stevens Creek. The site experienced
poor drainage and contributed to track out of sediment during all seasons. With the construction of the
Environmental Education Center and other improvements within the Preserve, expanded community
and school use,there was need for additional parking during large events and for oversized vehicles
such as school buses. To meet the parking demand and provide habitat restoration,the project was
designed to create a "green" meadow-style parking area compatible with the existing riparian setting.
Components of this improvement include 0.53 acres of parking surface paved with permeable concrete
including a gravel overflow area, planting thirty-seven native species trees, and adding approximately
20,000 square feet of new native riparian plants which will enhance the existing native habitat along
Stevens Creek. Construction is expected to be completed by September 1, 2019.
2.4.3 Apple Park
Apple Park lies on 152 acres of land that was formerly occupied by more traditional office space with
expansive impervious parking lots and multiple office buildings. Putting parking underground and
emphasizing California native landscaping,the Apple project reduced the impervious surface from
5,085,000 square feet (117 acres)to 2,615,000 square feet (60 acres).There was an emphasis on
planting native trees, enlisting the expertise of Stanford arborist, David Muffly.The campus drains to
flow-through planter bioretention treatment before entering the Calabazas watershed and features
9,000 trees, nearly double the 4,596 trees at the pre-project site.The project exceeded regulatory
requirements by providing stormwater treatment in the public right-of-way.
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City of Cupertino GSI Plan
3. INTEGRATION WITH OTHER PLANNING DOCUMENTS
To ensure the success of the GSI Plan and its implementation, its goals, policies and implementation
strategies should align with the City's General Plan and other related planning documents.The MRP
requires that municipal agencies review such documents and include in their GSI Plans a summary of any
planning documents aligned with the GSI Plan or updated or modified to appropriately incorporate GSI
requirements. The GSI Plan must also include a workplan identifying how GSI measures will be included
in future plans.
3.1 City Planning Document Review
The City completed a review of its existing planning documents to determine the extent to which GSI-
related language, concepts and policies have been incorporated. The plans that were reviewed are listed
below,with the General Plan as guiding planning document first, followed by remaining plans in order of
most recently prepared/adopted:
• General Plan—Community Vision 2040 (2015)
• Pedestrian Transportation Plan (2018)
• Storm Drain Master Plan (2018)
• Bicycle Transportation Plan (2016)
• Climate Action Plan (2015)
• Heart of the City Specific Plan (2014)
• Citywide Parks& Recreation System Master Plan (Draft)
The following sections provide a brief discussion of each plan and the extent to which it supports GSI
implementation. A prioritized workplan for the integration of GSI language into existing and future City
planning documents is provided in Section 3.1.18.
3.1.1 General Plan—Community Vision 2040
The City's Community Vision 2040 functions as the City of Cupertino's State-mandated General Plan and
covers a time frame of 2015-2040. Community Vision 2040 provides a framework for integrating the
aspirations of residents, businesses, property owners and public officials into a comprehensive strategy
for guiding future development and managing change. It describes long-term goals and guides decision-
making by the City Council and appointed commissions.The document was last amended in October
2015 and includes language that is very supportive of GSI. Examples of supportive language in the plan
are summarized below. No updates related to GSI are recommended at this time.
ES-3:Context, Urban Ecosystems(page ES-6):...the City is committed to enhancing the urban
ecosystem in the form of urban forestry management, integration of green infrastructure,
treatment of parks and open space, landscape and building requirements.
Strategy ES-1.1.1: Climate Action Plan (Page ES-14): Integrate multiple benefits of green
infrastructure with climate resiliency and adaptation
Goal ES-2.1.5 Urban Forest(Page ES-16): Encourage the inclusion of additional shade trees,
vegetated stormwater treatment and landscaping to reduce the "heat island effect" in
development projects.
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City of Cupertino GSI Plan
SE-5.1.1 Landscaping(page ES-21):Ensure that the City's tree planting, landscaping and open
space policies enhance the urban ecosystem by encouraging medians,pedestrian crossing and
curb-extension planting that is native, drought-tolerant, treats stormwater and enhances
urban plant, aquatic and animal resources in both, private and public development.
ES-5.1.2: Built Environment (page ES-21): Ensure that sustainable landscaping design is
incorporated in the development of City facilities,parks and private projects with the inclusion
of measures such as tree protection, stormwater treatment and planting of native, drought
tolerant landscaping that is beneficial to the environment.
Policy ES-7.1 Natural Water Bodies and Drainage Systems(page ES-24):In public and private
development, use Low Impact Development (LID) principles to manage stormwater by
mimicking natural hydrology,minimizing grading and protecting or restoring natural drainage
systems.
Policy ES-7.2: Reduction of Impervious Surfaces (page ES-24): Minimize stormwater runoff
and erosion impacts resulting from development and use low impact development (LID)
designs to treat stormwater or recharge groundwater
Strategy ES-7.2.1: Lot Coverage (page ES-24): Consider updating lot coverage requirements
to include paved surfaces such as driveways and ongrade impervious patios to incentivize the
construction of pervious surfaces.
Strategy ES-7.2.2: Pervious Walkways and Driveways (page ES-24): Encourage the use of
pervious materials for walkways and driveways...
Policy ES-7.2.3:Maximize Infiltration (page ES-25): Minimize impervious surface areas, and
maximize on-site filtration and the use of on-site retention facilities.
Strategy ES-7.3.1:Development Review(Page ES-25):Require LID designs such as vegetated
stormwater treatment systems and green infrastructure to mitigate pollutant loads and flows.
Strategy ES-7.4.1 Storm Drainage Master Plan (Page ES-25):Develop and maintain a Storm
Drainage Master Plan which identifies facilities needed to prevent "10-year" event street
flooding and "100-year"event structure flooding and integrate green infrastructure to meet
water quality protection needs in a cost effective manner.
Strategy ES-7.11.5 On-site Recycled Water(Page ES-27): Encourage on-site water recycling
including rainwater harvesting and gray water use.
Strategy ES-7.11.7 Green Business Certification and Water Conservation (Page ES-27):
Continue to support the City's Green Business Certification goals of long-term water
conservation within City facilities, vegetated stormwater infiltration systems, parks and
medians, including installation of low flow toilets and showers, parks, installation of
automatic shut-off valves in lavatories and sinks and water efficient outdoor irrigation.
Strategy INF-4.1.1:Stormwater Management (page INF-14): Reduce the demand on storm
drain capacity through implementation of programs that meet and even exceed on-site
drainage requirements
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City of Cupertino GSI Plan
3.1.2 Pedestrian Transportation Plan
Cupertino adopted its Pedestrian Transportation Plan (PTP) in 2002; an update was completed in
February 2018.The purpose of the PTP is to establish a guiding framework for the development and
maintenance of pedestrian facilities throughout Cupertino and recommend policies, programs, and
messaging to support and promote walking. Existing language in the PTP to support GSI is summarized
here:
Curb Extension Benefits(Page 38):Extended sidewalk space can be used for plantings, street
furniture, or green stormwater infrastructure.
Choker/Pinch Point Benefits (Page 41) Stormwater and greenspace elements can be
combined to calm traffic while also making the street more attractive.
3.1.3 Storm Drain Master Plan
The latest version of the City's Storm Drain Master Plan (SDMP) dated September 2018, was accepted by
City Council Resolution on January 15, 2019.The objective of the SDMP is to provide an examination of
the flood risks within the City limits and recommend actions necessary to accomplish defined levels of
service for storm drain systems owned by the City so as to appropriately manage flood risks.The SDMP
includes a discussion of the C.3 MRP Requirements and a discussion of GSI. Existing language to support
GSI is summarized here:
Section 2.2.2 Future Land Use: The majority of future development will involve the
redevelopment of sites, such as infill projects. Future development will need to comply with
C.3 requirements of the Municipal Regional Permit (MRP) for the Bay Area. These
requirements to treat storm water runoff may result in a reduction of impervious surface...
Section 5.7 Green Infrastructure: The City should look for and evaluate opportunities to
incorporate green infrastructure and LID facilities into the design of capital projects
recommended in the master plan.
3.1.4 Bicycle Transportation Plan
The City adopted a Bicycle Transportation Plan (BTP) in 2011 that describes long-term goals with respect
to the creation of a safe, convenient, and comprehensive network of bicycle facilities throughout the
City.The BTP was updated in 2016 to identify which priority projects have already been completed and
which remain to be implemented, and to identify any new projects that should be included for
prioritization. The BTP currently does not include language to support GSI. However, all bike lane
projects will be CIP projects and therefore reviewed annually as part of the review of projects for
potential GSI opportunities (See Section 6.2).
3.1.5 Climate Action Plan
The Climate Action Plan (CAP) defines Cupertino's path toward creating a healthy, livable, and vibrant
place for its current and future residents to live, learn, work, and play.The CAP seeks to identify
emissions reduction strategies that are informed by the goals,values, and priorities of the community.
The document was completed in January 2015.The CAP emissions reduction measures are organized
into five goals, one of which is "Expand Green Infrastructure". Existing language in support of GSI is
summarized below.
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City of Cupertino GSI Plan
GHG Overarching Goals (Pages ES-14 and 66): Expand Green Infrastructure: enhance the
City's existing urban forest and landscapes on public and private land.
Measure C-W-2 Recycled Water Irrigation Program(Page 116):As an alternative to recycled
water use...small-scale, on-site rainwater catchment systems could be installed to better
utilize natural precipitation for irrigation purposes, as opposed to use of scarce potable water
resources. The City will develop a demonstration project on municipal property...
Goal 5 — Expand Green Infrastructure (Page 127): In Cupertino, green space includes the
urban forest, parks, landscaped medians and parkways, and natural storm water-absorbing
landscapes. Healthy and robust green infrastructure systems can mitigate the urban heat
island effect, lower building energy use,provide natural stormwater management and wildlife
habitat, improve local air quality, and increase community pride.
Measure C-G-1 Urban Forest Program(Page 128): The City should incentivize Green roofs for
their role in "protecting water resources adversely impacted by climate change by reducing
electricity usage and improving air quality.
Measure C-G-1 Action D(Page 130):Evaluate opportunities to expand current ordinances and
codes to prioritize expansion of City's green and cool roofs, as well as pervious and cool
pavement.
Measure C-G-1 Action F(Page 130): Expand community and school gardens, and evaluate
opportunities to develop prevalent demonstration garden that incorporates water-sensitive
design and advanced irrigation control technology(if irrigation system is necessary.
Measure M-F-7 Action E. Install Graywater and Rainwater Catchment Systems in New
Construction and Major Retrofit Projects (page 186): In the absence of access to utility-
supplied recycled water in our community, Cupertino will strive to lead by example by installing
graywater and rainwater catchment systems in new municipal construction and major retrofit
projects...These projects can also serve as models for community members and businesses
seeking to achieve the same environmental and financial benefits, and should be showcased
to reconnect Cupertino's suburban residents to their backyard gardens and the natural water
cycle.
3.1.6 Heart of the City Specific Plan
The Heart of the City Specific Plan provides specific development guidance for the most important
commercial corridor in the City of Cupertino.The purpose of the specific plan is to guide the future
development and redevelopment of the Stevens Creek Boulevard Corridor in a manner that creates a
greater sense of place and community identity in Cupertino.The Streetscape Element implements
community design goals contained in the 1993 General Plan, design concepts subsequently developed
and revised in the 1993 "Heart of the City" Design Charette, and any new policies and concepts
identified in the 2005 General Plan.The document was enacted by the City Council in December 2014
and does not include language to support GSI. However, consistent with the City's strategy to ensure no
missed opportunities(Section 6), any development related to the Heart of the City will go through the
CIP review for identifying and evaluating GSI opportunities.
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City of Cupertino GSI Plan
3.1.7 Citywide Parks & Recreation System Master Plan (Draft)
The City is preparing a Citywide Parks& Recreation System Master Plan (Draft),which provides guidance
to create a park system for the future aligned with the community's values and priorities. The Master
Plan creates a vision through the year 2040 to guide future development, renovation, management and
activation of City parks and recreation facilities. Elements of the Master Plan goals include conservation
of trees and natural areas which support wildlife and ecological functions and establish sustainable
practices in management of parks and recreation facilities. Existing language in support of GSI in the
draft plan dated January 2019 is summarized here:
Conservation Goal 1.D.v (Page 39): Embrace storm water management, incorporating
green infrastructure elements such as rain gardens, bioswales, permeable pavers and
detention ponds to help reduce flooding,filter pollutants and replenish groundwater during
storm events.
Sustainability Goal7.C.ix(Page 73): Train staff in maintenance and stewardship of natural
areas, green infrastructure, and bioswales, so that these features thrive and the integrity of
natural resources on City property is maintained. Involve expert professional services as
needed to support informed and ongoing care for habitat areas.
Sustainability Goal 7.C.xi (Page 74): Focus on storm water management and green
infrastructure when designing or renovating City parks. For example, consider installing a
'storm water management garden' on City or public property to showcase green
infrastructure techniques.
Enhancements to Existing Parks, Creekside Park and Connection to Regnart Creek Trail
(page 84): Consider adding trail amenities, enhancing and protecting the riparian corridor,
and adding green infrastructure. Encourage connections between school, parks and trail.
Enhancements to Existing Parks, Saratoga Creek Trail (Page 84): Consider adding trail
amenities, enhancing and protecting the riparian corridor, and adding green infrastructure.
Encourage connections northward to Stevens Creek Blvd. and to regional destinations.
Enhancements to Existing Parks, Stevens Creek Trail (Page 84): Consider adding trail
amenities and adding green infrastructure. Encourage pedestrian and bike connections
between trail, City parks, County parks and nearby schools.
3.1.8 Workplan for Integration of GSI Language into Existing and Future City Planning
Documents
The General Plan, Climate Action Plan, Pedestrian Transportation Plan, Storm Drain Master Plan, and the
draft Citywide Parks and Recreation System Master Plan all include adequate language to support the
implementation of GSI in Cupertino.The Heart of the City Plan was last amended with the General Plan
in 2014. Unless there are development triggers,the Heart of the City Plan will be updated with GSI
language during future General Plan amendments. Consistent with the City's strategy(See Section 6.1),
any progress on the Heart of the City will go through the CIP review and green stormwater
infrastructure will be considered as part of that review.
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City of Cupertino GSI Plan
When preparing new planning documents,the City will review GSI Plan requirements during the
planning process to ensure that GSI requirements and policies are incorporated. Examples of GSI related
language can be found in existing City plans, and in references such as SCVURPPP's Model Green
Infrastructure Language for Incorporation into Municipal Plans (2016).
3.2 Regional Plans
The City is collaborating with SCVURPPP, Valley Water, and other agencies on several large-scale
planning efforts including those described below.
3.2.1 Santa Clara Basin Stormwater Resource Plan
A collaboration between SCVURPPP and Valley Water during 2017 and 2018,the Santa Clara Basin
Storm Water Resources Plan (SWRP) supports municipal GSI Plans by identifying and prioritizing
potential multi-benefit GSI opportunities on public parcels and street rights-of-way throughout the Basin
(i.e., Santa Clara Valley) and allows them to be eligible for State bond-funded implementation grants.
The SWRP includes a list of prioritized GSI opportunity locations for each SCVURPPP agency, including
Cupertino. As described in Section Error! Reference source not found.,the City's GSI Plan builds on the
SWRP output to further identify, evaluate, and prioritize potential projects.
3.2.2 Santa Clara Valley Water District's One Water Plan
Valley Water's Watershed Division is leading an effort to develop an Integrated Water Resources Master
Plan to identify, prioritize, and implement activities at a watershed scale to maximize established water
supply,flood protection, and environmental stewardship goals and objectives.The "One Water Plan"
establishes a framework for long-term management of Santa Clara County water resources, which
eventually will be used to plan and prioritize projects that maximize multiple benefits.The One Water
Plan incorporates knowledge from past planning efforts, builds on existing and current related planning
efforts; and coordinates with relevant internal and external programs.The One Water Plan has five
goals:
1. "Valued and Respected Rain"—Manage rainwater to improve flood protection,water supply,
and ecosystem health.
2. "Healthful and Reliable Water"—Enhance the quantity and quality of water to support
beneficial uses.
3. "Ecologically Sustainable Streams and Watersheds"—Protect, enhance and sustain healthy and
resilient stream ecosystems.
4. "Resilient Baylands"—Protect, enhance and sustain healthy and resilient baylands ecosystems
and infrastructure.
5. "Community Collaboration"—Work in partnership with an engaged community to champion
wise decisions on water resources.
Tier 1 of the effort, for which a draft plan was completed in 20166, is a countywide overview of major
resources and key issues along with identified goals and objectives.Tier 2 (2016 to 2020)will include
greater detail on each of the County's major watersheds. The City's GSI Plan aligns with the goals of the
6 Santa Clara Valley Water District. 2016.One Water Plan for Santa Clara County.An Integrated Approach to Water
Resources Management. Preliminary Draft Report 2016.
22
City of Cupertino GSI Plan
One Water Plan and may be able to coordinate with specific projects yet to be identified in the West
Valley area.
3.2.3 Bay Area Integrated Regional Water Management Plan
The Bay Area Integrated Regional Water Management Plan (IRWMP) is a comprehensive water
resources plan for the Bay region that addresses four functional areas: 1)water supply and water
quality; 2)wastewater and recycled water; 3) flood protection and stormwater management; and 4)
watershed management and habitat protection and restoration. It provides a venue for regional
collaboration and serves as a platform to secure state and federal funding.The IRWMP includes a list of
over 300 project proposals, and a methodology for ranking those projects for the purpose of submitting
a compilation of high priority projects for grant funding.The Santa Clara Basin SWRP was submitted to
the Bay Area IRWMP Coordinating Committee and incorporated into the IRWMP as an addendum. As
SWRP projects are proposed for grant funding, they will be added to the IRWMP list using established
procedures.
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City of Cupertino GSI Plan
4. GSI DESIGN GUIDELINES, DETAILS, AND SPECIFICATIONS
The MRP requires that the GSI Plan include general design and construction guidelines, standard
specifications and details (or references to those documents)for incorporating GSI components into
projects within the City.These guidelines and specifications should address the different street and
project types within the City, as defined by its land use and transportation characteristics, and allow
projects to provide a range of functions and benefits, such as stormwater management, bicycle and
pedestrian mobility and safety, public green space, and urban forestry.
The City, along with other SCVURPPP agencies, helped fund and provided input to the development of
countywide guidelines by SCVURPPP to address the MRP requirements and guide the implementation of
GSI Plans. The resulting SCVURPPP GSI Handbook (Handbook)'is a comprehensive guide to planning and
implementation of GSI projects in public streetscapes, parking lots and parks.The Handbook consists of
two parts,the contents of which are described in the following sections.The City intends to use this
Handbook as a reference when creating City-specific guidelines and specifications to meet the needs of
the various departments.
4.1 Design Guidelines
Part 1 of the Handbook provides guidance on selection, integration, prioritization, sizing, construction,
and maintenance of GSI facilities. It includes sections describing the various types of GSI,their benefits,
and design considerations; how to incorporate GSI with other uses of the public right-of-way, such as
bicycle and pedestrian infrastructure and parking; and guidelines on utility coordination and landscape
design for GSI. In addition,the Handbook also provides guidance on post-construction maintenance
practices and design of GSI to facilitate maintenance.
Part 1 also contains a section on proper sizing of GSI measures. Where possible, GSI measures should be
designed to meet the same sizing requirements as Regulated Projects,which are specified in MRP
Provision C.3.d. In general,the treatment measure design standard is capture and treatment of 80%of
the annual runoff(i.e., capture and treatment of the small, frequent storm events). However, if a GSI
measure cannot be designed to meet this design standard due to constraints in the public right-of-way
or other factors,the City may still wish to construct the measure to provide some runoff reduction and
water quality benefit and achieve other benefits. For these situations,the Handbook describes (in
Section 4.2) regional guidance on alternative design approaches developed by the Bay Area Stormwater
Management Agencies Association (BASMAA)for use by MRP permittees.
4.2 Details and Specifications
Part 2 of the Handbook contains typical details and specifications that have been compiled from various
sources within California and the U.S. and modified for use in Santa Clara County.The Handbook
includes details for pervious pavement, stormwater planters, stormwater curb extensions, bioretention
in parking lots, infiltration measures, and stormwater tree wells, as well as associated components such
as edge controls, inlets, outlets, and underdrains. It also provides typical design details for GSI facilities
'SCVURPPP(2019)Green Stormwater Infrastructure Handbook. February. Online at
http://scvurppp.org/scvurppp 2018/swrp/resource-li bra ry/
24
City of Cupertino GSI Plan
in the public right-of-way that address utility protection measures and consideration of other
infrastructure in that space.
4.3 Incorporation of SCVURPPP Details and Specifications into City Standards
The City plans to reference the SCVURPPP GSI Guidelines and Specifications for design of GSI projects.
The City will review these for consistency with its own local standards, and revise existing guidelines,
standard specifications, design details, and department procedures as needed.The City will also
reference details and build on its experience from design and construction of the Stevens Creek Corridor
and Creek Restoration Project (Section 2.4.1).
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City of Cupertino GSI Plan
5. GSI PROJECT PRIORITIZATION AND IMPERVIOUS TARGETS
To meet the requirements of the MRP,the City's GSI Plan must contain a mechanism to prioritize and
map areas for potential and planned projects, both public and private,for implementation over the
2020, 2030, and 2040 milestones.The mechanism must include the criteria for prioritization and outputs
that can be incorporated into the City's long-term planning and capital improvement processes.
This chapter describes different GSI project categories considered within the City,followed by a
description of the process employed by the City to identify public lands that offer opportunities to
implement GSI and prioritize those opportunities, and the results of the process.
5.1 Project Types
GSI project types that have been or may be implemented in the City fall into the following categories:
Early Implementation Projects, C3 Regulated Projects, Green Streets, LID Retrofits, and Regional
Projects. Green Streets, LID Retrofits, and Regional Projects are types of GSI capital projects that the
City may implement to meet the water quality goals in the MRP and multi-benefit objectives defined in
the GSI Plan. GSI capital projects are typically not regulated projects (although they must conform to the
sizing and design requirements contained in Provision C.3, except under certain circumstances) and they
are primarily public projects under control of the City.These three project types are the focus of the
prioritization process described in Section 5.2, but all five GSI project types are considered as part of the
City wide GSI strategy presented in Chapter 6. Several factors, such as change in scope of work,funding,
site conditions, etc. determine the ability of the City to implement GSI capital projects.
5.1.1 Early Implementation Projects
Early Implementation Projects are GSI projects that have already been implemented by the City or are
already scheduled and funded for implementation during the permit term (i.e., through December
2020).The City has already implemented one GSI projects, as discussed in Section 2.4.The City has
identified an additional Early Implementation project through a review of its Capital Improvement
Program (CIP), as discussed in Section 5.2.2 below.
5.1.2 Regulated Projects
C3 Regulated Projects are those implemented as part of new and redevelopment within the City, both
private and public,that must meet the post-construction stormwater treatment requirements per
Provision C.3 of the MRP. Regulated projects include private development or redevelopment projects,
such as multi-family residential buildings, commercial office buildings, or shopping plazas, as well as
public projects, such as libraries, police stations, and parking lots, exceeding the impervious surface
thresholds.The "Apple Park" project, a 176-acre site that replaced the former Hewlett Packard industrial
campus and includes LID measures, is an example of a regulated project.
5.1.3 LID Projects
LID projects mitigate stormwater impacts by reducing runoff through capture and/or infiltration and
treating stormwater on-site before it enters the storm drain system. LID projects may include
bioretention facilities, infiltration trenches, detention and retention areas in landscaping, pervious
pavement,green roofs, and systems for stormwater capture and use. For the purposes of the GSI Plan,
LID projects are GSI facilities that treat runoff generated from a publicly-owned parcel on that parcel.
26
City of Cupertino GSI Plan
5.1.4 Regional Projects
Regional projects capture and treat stormwater runoff from on-site and off-site sources, including
surface runoff and diversions from storm drains. Benefits of regional stormwater capture projects can
include flood risk reduction, stormwater treatment and use, and groundwater recharge.These projects
may take a variety of forms such as detention and retention basins and subsurface vaults and infiltration
galleries.The site characteristics will determine what types of regional projects are feasible, e.g.,
whether a project is on-line or off-line from the storm drain network,whether it is desirable to change
the functionality of the site, whether the project is above ground or underground, and the size of the
project.
5.1.5 Green Street Projects
Green street projects are GSI opportunities in the public right-of-way that capture runoff from the street
and adjacent areas that drain to the street.The technologies used for green streets are similar to those
used in LID projects but are limited to designs that can be used in the right-of-way. Green street projects
may include bioretention (e.g., stormwater planters, stormwater curb extensions or stormwater tree
filters), pervious pavement, and/or infiltration trenches. Green street GSI features can be incorporated
into other improvements in the right-of-way, including complete streets designs and improvements for
pedestrian and cyclist safety.
5.2 Identification and Prioritization Process
The City of Cupertino GSI opportunity identification and prioritization process involved two steps.The
first step was the screening and prioritization methodology used in the Santa Clara Basin SWRP (see
Section 3.2.1)to identify and prioritize GSI opportunities on public parcels and street segments within
the region. The second step in the process involved overlaying City-specific priorities, planning areas,
and upcoming City projects onto the regional prioritization results to align the results of the SWRP
prioritization process with the City's priorities.These steps are described in detail below.
City projects in areas associated with a project opportunity identified in the SWRP can qualify for State
bonded-funded stormwater capture project implementation grants (e.g., Proposition 1). Opportunities
for GSI implementation that arise in areas that are not adjacent to a prioritized project opportunity
identified in the SWRP may be considered on a case by case basis for feasibility, cost effectiveness, and
availability of funding.
5.2.1 Step 1: Stormwater Resource Plan Prioritization
Building on existing documents that describe the characteristics and water quality and quantity issues
within the Santa Clara Basin (i.e., the portion of Santa Clara County that drains to San Francisco Bay),the
SWRP identified and prioritized multi-benefit GSI opportunities throughout the Basin, using a metrics-
based approach for quantifying project benefits such as volume of stormwater infiltrated and/or
treated, and quantity of pollutants removed. The metrics-based analysis was conducted using
hydrologic/ hydraulic and water quality models coupled with Geographic Information System (GIS)
resources and other tools.The products of these analyses were a map of opportunity areas for GSI
projects throughout the watershed, an initial prioritized list of potential project opportunities, and
strategies for implementation of these and future projects.
27
City of Cupertino GSI Plan
The process began by identifying and screening public parcels and public rights-of-way'that can support
GSI. Project opportunities were split into the three categories described above—LID, regional, and green
streets projects-- because of fundamental differences in GSI measures used, project scale, and
measures of treatment efficiency. Screening factors are presented in Table 5-1.
After the identification of feasible GSI opportunity locations, screened streets and parcels were
prioritized to aid in the selection of project opportunities that would be the most effective and provide
the greatest number of benefits. In addition to physical characteristics, several special considerations
were included in the prioritization methodology to consider coordination with currently planned
projects provided by agencies, as well as consideration of additional benefits that projects could
provide. A discussion of the screening and prioritization process for each project category is presented
in the subsequent sections. Figure 5-1 presents the results of the various steps.
LID and Regional Stormwater Capture Project Opportunities
The screening criteria for LID and regional projects were ownership (focusing only on public parcels),
land use, and site slope.As shown in Table 5-1, parcel size was used to determine whether a location
could support a regional or LID project.
Parcels that met the screening criteria were prioritized based on physical characteristics such as soil
group, slope, and percent impervious area, proximity to storm drains, proximity to flood-prone creeks
and areas, proximity to potential pollutant sources (e.g., PCBs'), whether they were in a priority
development area (PDA),whether they were within a defined proximity to a planned project, and
whether the project was expected to have other benefits such as augmenting water supply, providing
water quality source control, re-establishing natural hydrology, creating or enhancing habitat, and
enhancing the community. Prioritization metrics for LID project scoring and regional project scoring are
shown in separate tables in Appendix A.The result of the parcel prioritization was a list and map of
potential project locations based on the above criteria.This subset of projects from the SWRP was
carried over into Step 2 City-Specific Prioritization (Section Error! Reference source not found.).
8 Public parcels can include those not owned by the City,such as public school grounds,County,State,and Federal properties,
and property owned by the Water District.
9 Polychlorinated biphenyls—manmade chemicals which resist extreme temps,and were used in electrical equipment such as
transformers and capacitors;and building materials such as caulking,adhesives,mastics etc.primarily from 1950s through
1981. PCBs pose developmental or neurological risks to fetuses,babies,and children,and have been shown to cause cancer in
animals and evidence supports cancer causing effect in PCB workers.
28
City of Cupertino GSI Plan
Table 5-1 Screening factors for parcel-based and right-of-way project opportunities
Screening
Factor Characteristic Criteria Reason
Parcel-based
County, City,Town,
Valley Water, State,
Public Ownership p p Identify all public parcels for regional
Open Space
Parcels Agencies stormwater capture projects or onsite LID
retrofits
Land Use Park, School, Other
(e.g., Golf Course)
>_0.25 acres Opportunity for regional stormwater capture
Parcel Size project
Suitability < 0.25 acres Opportunity for on-site LID project
Site Slope < 10% Steeper grades present additional design
challenges
Right-of-Way
Selection
Ownership Public Potential projects are focused on public right-
of-way opportunities
Surface Paved Only roads with paved surfaces are considered
suitable. Dirt roads were not considered.
0
Steep grades present additional design
Suitability Slope < 5/ challenges; reduced capture opportunity due
to increased runoff velocity
Speed <—45mph Excludes higher speed roads such as major
arterials and highways
Green Street Project Opportunities
The screening criteria for green streets projects in the public right-of-way were ownership, surface
material, slope, and speed limit (Table 5-1).The screened public right-of-way street segments were then
prioritized based on physical characteristics, proximity to storm drains, proximity to flood-prone creeks
and areas, proximity to potential pollutant sources (e.g., PCBs10), whether they were in a priority
development area, whether they were in proximity to a planned project, and whether the project was
io Polychlorinated biphenyls—manmade chemicals which resist extreme temps,and were used in electrical equipment such as
transformers and capacitors;and building materials such as caulking,adhesives,mastics etc. primarily from 1950s through
1981. PCBs pose developmental or neurological risks to fetuses,babies,and children,and have been shown to cause cancer in
animals and evidence supports cancer causing effect in PCB workers.
29
City of Cupertino GSI Plan
expected to have other benefits (similar to LID and regional projects). Prioritization metrics for green
streets projects are shown in Appendix A.
The initial prioritization process resulted in a large number of potential green streets project
opportunities within the Santa Clara Basin. In order to identify the optimal locations for green street
projects,the street segments in each municipality's jurisdiction with scores in the top 10 percent of
ranked green street opportunities were identified and mapped.
5.2.2 Step 2: City-Specific Prioritization
The City reviewed the results from the SWRP prioritization (Section 5.2.1) and refined the list of parcels
and street segments based on current knowledge of City plans and project opportunities. The resulting
parcel-based and green street opportunities for the City of Cupertino are presented in Figure 5-1.The
City's list of parcel-based and green street opportunities is provided in tabular format in Appendix B.
Next, as discussed in the remainder of this section,the City-specific prioritization incorporated local
priorities for GSI project implementation,which include: 1) opportunities to implement GSI projects in
conjunction with anticipated areas of private development and 2) upcoming capital improvement
projects that can potentially be combined with GSI projects.
Priority Development Areas
Priority Development Areas, commonly known as PDAs, are areas within existing communities that local
city or county governments have identified and approved for future growth.These areas typically are
accessible by one or more transit services; and they are often located near established job centers,
shopping districts and other services. PDAs are expected to accommodate 78% of new housing
production (over 500,000 units) and 62%of employment growth (almost 700,000 jobs) in the Bay Area
through the year 204011. As PDAs are developed,they offer good opportunities to construct GSI
facilities.
Cupertino's PDA area includes properties within a quarter mile of Stevens Creek Boulevard from
Highway 85 to its eastern border and a portion of North and South De Anza Boulevards.The boundary of
the PDA is shown in Figure 5-2.
11 From Table 4.2 and Table 4.3 of the Association of Bay Area Governments and Metropolitan Transportation Commission
"Plan Bay Area 2040"Report,adopted July 26,2017.
30
City of Cupertino GSI Plan
City of Cupertino - Public Parcels and Street Segments with GSI Opportunities
Homestead Rd af
m
a
M Z W
L)
Q �
a Stevens Creek BlvLL
0
® r
McClellan Rd
� as
a� CM
c
Prospect Rd
Public Parcels and Street Segments
with Opportunities for GSI
0 Public Buildings
Parks/Open Space
Street Segments
Q City Boundary
O Roads
N
D 0.25 0.5 1
Miles
Figure 5-1 City of Cupertino Public Parcels and Street Segments with Opportunities for GSI(Source:EOA,and
Santa Clara Basin Stormwater Resource Plan,2018).
31
City of Cupertino GSI Plan
Special Areas
The City's General Plan identifies nine Special Areas within Cupertino:
• Heart of the City
• Vallco Shopping District
• North Vallco Park
• South De Anza
• North De Anza
• Homestead
• Bubb Road
• Monta Vista Village
• Other Non-Residential/Mixed-Use Special Areas
Each Special Area is located along one of the four major mixed-use corridors in the city,which represent
key areas within Cupertino where future development and reinvestment will be focused. Goals for these
areas include more bicycle-and pedestrian-friendly streets and improved walkable, bikeable
connectivity to adjacent areas and services. Because these Special Areas are where the most
development is expected to occur,they will likely have the best opportunities to construct GSI facilities.
The GSI projects could be part of private redevelopment projects or public improvement projects.
The location of the Special Areas are shown on Figure 2-2, with the exception of the Other Non-
Residential/Mixed-Use Special Areas.These Other Non- Residential/Mixed-Use Special Areas are
located throughout Cupertino and include the following: west side of Stevens Canyon Road across from
McClellan Road; intersection of Foothill Boulevard and Stevens Creek Boulevard; Homestead Road near
Foothill Boulevard; northwest corner of Bollinger Road and Blaney Avenue; and all other non-residential
properties not referenced in an identified commercial area.
32
City of Cupertino GSI Plan
City of Cupertino - Planning Areas
Homestead Rd a
o
A m Z C
B D
CO
4
0
Stevens Creek Blvd E
o
F�� �Q
McClellan Rd
Y
U
� `U
12
CO
G �
com H
Prospect Rd
m
a
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c
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m
0
in
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60
Special Areas ® Priority Development Area (PDA)
A- Homestead
B - North De Anza Q City Boundary
C - North Vallco Park
Roads
D - Vallco ShoppingDistrict o
E - Heart of the City
F - Bubb Road
G - Monta Vista Village
H - South De Anza
0 0.35 0.7 1.4 N
Miles A
Figure 5-2. City of Cupertino Special Project Areas and Priority Development Area(Source:City of Cupertino
General Plan)
33
City of Cupertino GSI Plan
Capital Improvement Projects
As required by the MRP,the City reviews its CIP project list annually to identify opportunities for GSI.
Based on this review,the City prepares and maintains a list of any public GSI projects that are planned
for implementation during the permit term and a list of public projects that have potential for GSI
measures.
As discussed in Section 2.4.2, the City has completed one public GSI project (Stevens Creek Corridor and
Creek Restoration Project).The second public GSI project (McClellan Ranch West Parking Lot
Improvement) is under construction and expected to be completed in September 2019.The project
locations are shown on the map in Figure 5-4.
In addition, through its CIP project review,the City identified the following projects as having potential
to include GSI:
• South Foothill Blvd and N. Foothill Blvd.Green Street: Reconstruct the medians to reduce
runoff and better infiltrate stormwater, and consider bioretention areas along the outer edges
of the boulevard
• Union Pacific Railroad Trail Feasibility Study: Incorporate bioretention areas and pervious trails,
if the study results in a project. Currently this is just a study.
• Mary Avenue Greenbelt and Trail Project: Create a wide bioretention-enhanced green belt on
the west side of Mary Avenue. Include a pervious multi-use pathway to accommodate bicyclists,
pedestrians, strollers, and joggers. Install bioretention tree wells at optimal intervals on the east
side of the street to treat stormwater, and on the west side of the street where feasible to
create a future tree canopy over Mary Ave.
• Junipero Serra Trail Extension: Incorporate bioretention areas and pervious trails where
feasible.
• Memorial Park Renovation: Look for an opportunity to construct an infiltration basin at the park
to treat runoff from Stevens Creek Blvd.
• Regnart Creek Trail: Incorporate bioretention areas and pervious trails where feasible.
• Lawrence Mitty Park: Pending the City acquiring the land, look for opportunities to incorporate
GSI features to treat runoff from the adjacent expressway.
• Stelling Road Potential Future Storm Drain and Street Upgrades: Incorporate bioretention
areas to treat street runoff where feasible.
• Rainbow Drive Storm Drain Pipeline Rehabilitation: Incorporate bioretention areas to treat
street runoff where feasible.
• Wolfe Road Widening: Incorporate bioretention areas where feasible
• Bike Boulevard Projects: Cupertino is planning a network of bicycle-friendly routes along
residential streets throughout the City in order to encourage bicycling. Traffic circles and bulb
outs will be considered and designed,where feasible,to include GSI features.
• Citywide Parks and Recreation Master Plan: Install GSI at Linda Vista, Memorial, Monte Vista,
Wilson, Portal, Creekside and other parks where feasible, which could include enhanced
educational signage explaining the function and purpose of the GSI improvements.
34
City of Cupertino GSI Plan
These potential CIP project locations are shown on the map in Figure 5-3.A GSI concept for the Mary
Avenue Greenbelt and Trail Project was completed for the SWRP. The project is currently unfunded, and
the concept design is intended to assist with the grant application process should the City decide to
pursue funding via Proposition 1 or other State bond-funded grant program.
35
City of Cupertino GSI Plan
City of Cupertino - Public Projects with Potential for GSI
Homestead Rd
m
o
4 n 10
noJ
N
3 Q
CD
1m 2 5
Z 0 Stevens Creek Blvd
0
Mc Clellan Rd
8
OZ T
C X
X
CO � lLl
s � U
1 Prospect Rd
U)
0
m
m
U)
0 Public Projects with Potential for GSI Bike Blvds Project
1 - S. Foothill Blvd & N. Foothill Blvd Citywide Parks & Recreation
Green Street Master Plan
2 - Union Pacific RR Trail Feasibility Study
3 - Mary Ave & Greenbelt Trail Project Q City Boundary
4 - Junipero Serra Trail o Roads
5 - Memorial Park Renovation
6 - Regnart Creek Trail
7 - Lawrence Mitty Park
8 - Stelling Road Potential Future Storm Drain
& Street Upgrades
9 - Rainbow Dr Storm Drain Pipeline Rehabilitation N
10 - Wolfe Road Widening ° 0.25 o.s tMiles A
Figure 5-3. City of Cupertino Public Projects with Potential for GSI(Source:City of Cupertino Fy 17-18 Annual
Report,and 2018 Santa Clara Basin Stormwater Resource Plan)
36
City of Cupertino GSI Plan
5.3 Prioritization Output
The map in Figure 5-4 presents a compilation of the factors used to identify and prioritize the City's
opportunities for GSI projects:the City's list of parcel-based and green street project opportunities,
overlaid with the City's PDA, Special Areas, and CIP projects that may have potential to include GSI.The
locations of the City's completed GSI projects, including the McClellan Ranch West Parking Lot project
which is under construction and expected to be completed by September 2019, are also shown.As
shown in Figure 5-4, a large number of the green street opportunities identified in the SWRP are located
within the City's PDA and Special Areas.This indicates a strong correlation between the areas identified
as having potential for GSI and the City's construction and redevelopment plans.
The City's list of parcel-based and green street opportunities is provided in tabular format in Appendix B.
The list includes additional information for each parcel and green street opportunity, including general
information such as APN, landowner and land use or street name,the SWRP prioritization score for each
project opportunity, and co-location with a City criteria for prioritization (CIP project, PDA or Special
Area).
An implementation plan is described in Section 6 to guide the development, design, and construction of
GSI projects.
37
City of Cupertino GSI Plan
City of Cupertino - GSI Overview
Homestead Rd
0
um Z 1
�N C
A N
B
1 �
o1L D
L 2 S evens4,ree Blvd E..
0
_ X
G Ui
F
3 McClellan Rdm
5 �
4z� 1k,
c
o �
h m
� H
Prospect Rd
c
07
M
0
m
L
U) 0 0.2 0.4 0.8 q
Miles N
Public Parcels and Green Street Segments Special Areas
with Opportunities for GSI
A-Homestead
Public Buildings B-North De Anza
- Parks/Open Space C-North Vallco Park
D-Vallco Shopping District
Street Segments E-Heart of the City
F-Bubb Road
- Public Projects with Potential for GSI G-Monta Vista Village
O Existing GSI Project H -South De Anza
1 -Apple Campus/Park F77 Priority Development Area(PDA)
2-Stevens Creek Corridor Park& Restoration
3-McClellan West Parking Lot Q City Boundary
(target completion Sept 2019) Roads
Figure 5-4 City of Cupertino GSI Overview
38
City of Cupertino GSI Plan
6. GSI Implementation Plan
This chapter provides an overall strategy and steps for implementing GSI within the City of Cupertino
over the long term.The implementation plan has the following components: (1)the Citywide GSI
strategy; (2) a process for identifying and evaluating GSI opportunities, (3) a workplan to complete Early
Implementation Projects, (4)the legal and funding mechanisms that enable implementation, (5)
estimated targets for the amounts of impervious surface to be "retrofitted" (i.e., redeveloped with GSI
facilities to treat runoff from impervious surfaces), and (5)the technical tools that ensure the tracking of
implemented projects.
6.1 City-wide GSI Strategy
The City of Cupertino's approach to GSI planning will be consistent with the City's Community Vision
2040 (See Section 3.1.1), which has as guiding principle to:
"Preserve Cupertino's environment by enhancing or restoring creeks and hillsides to their
natural state, limiting urban uses to existing urbanized areas, encouraging environmental
protection, promoting sustainable design concepts, improving sustainable municipal
operations, adapting to climate change, conserving energy resources and minimizing
waste."
The City's approach will also be guided by various other existing plans that support the implementation
of GSI, such as the Climate Action Plan, and the Storm Drain Master Plan. Cupertino has already
completed one project,the Stevens Creek Corridor and Restoration Project (Section 2.1.4),which
incorporated GSI and preserved an 18-acre site and restored creek habitat in the City to maintain
biodiversity and ecological integrity of local natural systems. As the City seeks to achieve sustainability
and community health objectives,future growth and retrofitting of existing infrastructure will create
mixed-use, commercial, employment and neighborhood centers; pedestrian-oriented and walkable
spaces for the community to gather; and distinct and connected neighborhoods with easy walkable and
bikeable access to services, including schools, parks and shopping.
The City of Cupertino's GSI implementation strategy consists of the following:
• Priority Development Areas -The City will focus future change within the Special Areas that are
located on Cupertino's major mixed-use corridors.These areas already have a mix of
commercial, office, hotel and residential uses, and are located along roadways that will be
enhanced with "Complete Streets" features, improved landscaping and expanded public spaces
(e.g., parks and plazas). Complete Streets can be enhanced with GSI features to become green
"Sustainable Streets".
• Evaluation of CIP Projects for Opportunities—The City will continue to review its CIP list annually
for opportunities to incorporate GSI into CIP projects and evaluate the feasibility of such
projects.The City has established a process for CIP review to avoid missing GSI opportunities
(see Section 6.2).
• Evaluation of Opportunities Identified in the Stormwater Resource Plan—The public parcels and
street segments identified in the SWRP (See Section 5.1 of this report) are opportunity areas for
GSI projects.The City will use the SWRP list to help identify potential project locations for GSI
implementation, as described in Section 6.2.
39
City of Cupertino GSI Plan
• Evaluation of Non-CIP Project Opportunities-As awareness of GSI increases, municipal staff or
local community members may also identify and recommend GSI projects opportunities.These
projects will be considered using the methodology described in Section 6.2.
• Coordination with Private Development—The City of Cupertino will explore working with private
property developers to install green infrastructure facilities in public rights-of-way near the
properties they are developing, such as along street frontages.
• Community Outreach and Engagement—The City will provide outreach to the Sustainability
Commission,the Bike and Pedestrian Commission,the local community, and other stakeholders
to get input and support for the implementation of the GSI Plan.The City will also continue to
engage with San Francisco Estuary Institute (SFEI) and/or other potential partners that offer a
regional perspective for enhancing sustainable natural landscaping with multi-faceted benefits.
The City will also continue to require future development projects to comply with C.3 requirements of
the Municipal Regional Permit(MRP), and include site design, source control,treatment control, and
hydromodification management measures as applicable.
6.2 Process for Identifying and Evaluating GSI Project Opportunities
The City will use the various mechanisms described in its strategy(Section 6.1)to identify GSI
opportunities in public projects.
The City will use the guidance developed by BASMAA12 (see Appendix D) and the SWRP prioritization
criteria to evaluate public projects to determine the potential for the inclusion of GSI measures at the
project planning level.The evaluation may include site reconnaissance, drainage area delineation, and
cost analysis. If not already on the CIP list, projects identified through this process will be added to the
CIP list when it is updated. Projects with a GSI component may be included in the CIP as funded or
unfunded projects. An unfunded project's inclusion in the CIP demonstrates that it is a City priority
pending adequate funding.The City prepares the CIP Budget biennially.The next Biennial CIP Budget will
be prepared in 2020 covering FY 2020-21 and FY 2021-22.
The City will map all potential GSI project opportunities to determine their proximity to green street or
parcel-based project opportunities identified in the SWRP (Section 5.2.1). Potential GSI projects that are
adjacent to SWRP opportunity areas may be eligible for state bond funding. Projects with opportunities
for GSI measures may be submitted to the SWRP during the SWRP update process if they are not already
included in the SWRP.This will allow those projects to be eligible for future state bond funding.The
SWRP will likely be updated in the 2022-2023 timeframe.At this time, SCVURPPP will reach out to all
member agencies to provide their project lists for prioritization and inclusion in the updated SWRP.
6.3 Workplan to Complete Early Implementation Projects
As discussed in Section 5.2.2 of this GSI Plan, Provision C.3.j. of the MRP requires that the City identify,
prepare, and maintain a list of GSI projects that are planned for implementation during the permit term
(i.e.,through December 2020), and infrastructure projects that have potential for GSI measures.The list
12 BASMAA Development Committee (2016)Guidance for Identifying Green Infrastructure Potential in Municipal
Capital Improvement Program Projects. May.
40
City of Cupertino GSI Plan
is submitted with each Annual Report to the Regional Water Board. Projects with GSI that are scheduled
and funded for implementation during the permit term are considered "Early Implementation Projects".
The City has already identified and completed one early implementation project (Stevens Creek Corridor
and Creek Restoration Project),with a second project(McClellan West Parking Lot) currently under
construction and expected to be completed by September, 2019(see Section 2.4).
The City will continue to review its CIP list annually, using the SWRP prioritization and the guidance
developed by BASMAA for identifying opportunities to incorporate GSI into CIP projects. A copy of the
BASMAA Guidance is provided in Appendix D.
6.4 Legal Mechanisms for GSI Implementation
Provision C.3.j.i.(3) of the MRP requires permittees to "Adopt policies, ordinances, and/or other
appropriate legal mechanisms to ensure implementation of the Green Infrastructure Plan in accordance
with the requirements of this provision."
As described in Section 1.3.2,the City of Cupertino and other municipalities subject to Provision C.3 of the
MRP must require post-construction stormwater control measures on regulated development projects.
Post-construction stormwater controls reduce pollutants from flowing to streams, creeks, and the Bay
and reduce the risk of flooding by managing peak flows. Section 9.18.100 (Permanent Stormwater
Measures Required for Development and Redevelopment Projects)of the City's Municipal Code provides
legal authority for the City to require regulated private development projects to comply with MRP
requirements.
GSI projects are typically not regulated projects (although they must conform to the sizing and design
requirements contained in Provision C.3 except under certain circumstances) and they are primarily
public projects under control of the City. As part of the GSI Plan process,the City reviewed its existing
policies, ordinances, and other legal mechanisms related to the implementation of stormwater NPDES
permit requirements and found that it has sufficient legal authority to implement the GSI Plan.Adoption
of the GSI Plan by the City Council further strengthened the authority.
6.5 Evaluation of Funding Options
The GSI Plan prioritizes specific projects for near-term integration into CIPs and long-term integration into
City planning efforts. Implementation of these projects is contingent upon the City identifying funding
sources for GSI planning, design, construction, and maintenance.
The total cost of GSI includes costs for planning, capital (design, engineering, construction) and ongoing
expenditures, including operations and maintenance (O&M), utility relocation, and feature replacement.
It is likely that no single source of revenue will be adequate to fund implementation of GSI, and a
portfolio of funding sources will be needed.There are a variety of approaches available to help fund up-
front and long-term investments.This section discusses the City's current stormwater management
funding sources and then describes additional funding strategies available to implement GSI that are
being considered by the City for future funding.
6.5.1 Current Funding Sources for GSI Program Elements
The City of Cupertino currently uses a combination the City's General Fund and Federal, State, and other
applicable grants to fund construction of projects in its capital improvement program (CIP) and other
projects.The General Fund, and when applicable, CalRecycle grants, are used for public street, parking
41
City of Cupertino GSI Plan
lot and building maintenance; maintenance of stormwater control measures installed at public projects;
and maintenance of other landscaped areas (e.g., parks, medians, public plazas, etc.)
6.5.2 Potential Future Funding Options
As required by the MRP,the City analyzed possible funding options to raise additional revenue for
design, construction, and long-term operation and maintenance (O&M) of GSI projects.The City used
the guidance on stormwater funding options developed by SCVURPPP (2018) as a reference for
conducting its analysis. Table 6-1 summarizes the funding options that will be considered by the City as
the Plan is implemented. For each type of funding mechanism,the table provides a brief overview and
specifics related to GSI, pros and cons, and applicability to funding planning, capital, and/or long-term
O&M costs.
6.6 Impervious Area Targets
As mentioned in Section 1.3.2,the focus of the GSI Plan is the integration of GSI systems into public
rights-of-way. However, the MRP (Provisions C.11 and C.12) establishes a linkage between public and
private GSI features and required reductions of pollutants in stormwater discharges. To help estimate
the pollutant load reductions that can be achieved by GSI during the 2020, 2030, and 2040 timeframes,
the MRP requires that Permittees include in their GSI Plans estimated targets for the amounts of
impervious surface to be "retrofitted" (i.e. redeveloped with GSI facilities to treat runoff from
impervious surfaces) as part of public and private projects during the same timeframes.
The City worked with SCVURPPP staff to develop a methodology to predict the extent and location of
privately-and publicly-owned land areas that will be redeveloped in their jurisdictions and whose
stormwater runoff will be addressed via GSI facilities, and to derive impervious surface targets for GSI
retrofits associated with these redevelopment projects. The methodology and results are described in
Sections 6.6.1 and 6.6.2 below.
6.6.1 Methodology
The first step in the process used historic development trends and City staff's knowledge of
planned/projected redevelopment in the City to estimate the acres of redevelopment that will occur in
the City by 2020, 2030, and 2040 via redevelopment of privately- and publicly-owned parcels that would
trigger C.3 requirements under the current MRP (i.e. C.3 regulated projects). Stormwater runoff
associated with these parcels will be addressed via GSI facilities, as required by the permit.
The second step was to estimate the acres of impervious surface associated with future redevelopment
of these private and public parcels.To do this, it was necessary to predict the likely locations and types
of land areas that are anticipated to be addressed by GSI in the future. Growth patterns and time
horizons for development, along with algorithms to identify which parcels are likely to redevelop,
resulted in preliminary estimates of the land area that is predicted to be addressed by GSI facilities in
the City of Cupertino by 2020, 2030, and 2040. Using the current land uses of the predicted locations of
GSI implementation and associated impervious surface coefficients for each land use type, estimates of
the amount of impervious surface that would be retrofitted with GSI on privately-owned parcels were
developed.
The methodology focused on parcel-based redevelopment as the location and timing of projects in the
public right-of-way is uncertain and the contribution of these projects to overall impervious surface area
treated by GSI expected to be minor relative to the acreage projected to be treated by C.3 projects.
42
City of Cupertino GSI Plan
Table 6-1 Potential GSI Funding Options
Section/Overview GSI Specifics Pros Cons Type of Funding
Parcel Taxes: revenue Can be used to set up, • Well understood tax • High political threshold • Planning
stream through taxing fund and maintain a • Stable revenue stream • Vulnerable to competition with other • Capital
property or other stormwater program over many years measures on the ballot. • O&M
system. and MRP compliance. • Legally reliable • Considerable effort and resources
• Can also be done by required with uncertain odds of
mail. success.
Property-related Fees: • Fee on property • Most-commonly used • Property-based fees must use a • Planning
fees on real property. contributing mechanism for funding standardized methodology for • Capital
stormwater stormwater programs. calculating the fee. • O&M
runoff to MS4. • Easier to pass with 50% • Considerable effort and resources
• Can be used to threshold and mailing required with uncertain odds of
set up,fund and process. success.
maintain a • Approval process is more time
stormwater consuming and expensive for staff.
program and MRP • Schools may have large fees and public
compliance. schools may be exempt from fees
depending on the agency's specific
ordinance.
General Obligation • Tax on property • Typically a lower • Interest rate variable depending on • Planning
Bonds owners through interest rate than what financial markets • Capital
debt obligation is available from • Some risk to general fund for
taken on by commercial banks. municipality if payments cannot be
municipality. • Allows funds to be used made.
• Long term in the near term and • Can only be used for capital costs—
payback period paid back over the long not 0&M
typically 10-30 term.
years.
43
City of Cupertino GSI Plan
Section/Overview GSI Specifics Pros Cons Type of Funding
Development Impact Could potentially be Cost for retrofitting streets If a fee is found to not relate to the impact . Planning
Fees: paid by an used to fund retrofits can be leveraged through created by the development project,or to . Capital
applicant seeking of adjacent public development activities. exceed the reasonable cost of providing
approval of a right-of-way areas the public service,then the fee may be
development project. with GSI as part of declared a "special tax'subject to approval
development or by a two-thirds majority of voters.
redevelopment
projects.
Grants:one time funds Could be used to plan, Can fund programs or • Usually a one-time source of funding • Planning
that require an design and/or build systems that would only. • Capital
application from a GSI. otherwise take up significant • May need to create new programs and
funding agency. general fund revenues. systems for each grant.
• Usually have strings attached for
matching funds and other
requirements.
• Little control over timing of
applications and payment can lead to
difficulties in coordination with other
programs and grants.
• Can be very competitive and resource
intensive to apply.
• No guarantee of success.
• Post-project O&M costs must be
borne by the agency.
Benefit Assessment and Typically used to build Can be used to fund Requires property owners and/or . Capital
Community Facility and/or maintain maintenance and businesses to agree that the need is . O&M
Districts facilities such as GSI operations. present and that they should be(at least
improvements and/or partially) responsible for funding it.
services.
44
City of Cupertino GSI Plan
Section/Overview GSI Specifics Pros Cons Type of Funding
Business Improvement Businesses and Can provide sense of Can burden businesses, property owners • Planning
Districts property owners tax ownership and pride in the and others to the extent that they are • Capital
themselves and neighborhood when results unwilling to approve other funding • O&M
manage the funds to are visible. measures.
build or maintain GSI
assets.
Infrastructure Financing Captures increase in Can be jointly done with Cannot capture any of the local school • Planning
Districts ad valorum tax multiple cities. district's portion of tax increment. • Capital
increases(similar to • O&M
redevelopment
agencies)for
infrastructure
improvements such
as GSI
Motor Vehicle License Could be used to plan, Can be flexible in purpose • If the total number of new annual • Planning
Fees:fees on each motor design and/or build and can supply a long-term motor vehicle registrations decline • Capital
vehicle that is registered. GSI. stable revenue source. over time(as may happen with car-
sharing,transit increases, biking and
walking and the rollout of automated
vehicles) revenues will decline.
• Difficult to achieve the 2/3 majority
needed to pass due to Prop 26.
• Only for activities that are deemed to
help mitigate impacts from motor
vehicles.
45
City of Cupertino GSI Plan
Section/Overview GSI Specifics Pros Cons Type of Funding
Realignment of Could be used to plan, A means of leveraging • Bureaucratic issues can be difficult to • Planning
Municipal Services: design, build and/or existing or new resources overcome. • Capital
municipalities shift costs maintain GSI where funded by non-balloted fee • Sewer,trash and water may be • O&M
to programs where there is a nexus structures. controlled by different agencies that
revenue can be increased between the two may not be able to coordinate or
such as sewer,water and programs. share resources.
trash. 0 There may be political restrictions to
significant increases in rates.
Integration with Installation and . Roadway projects have • Roadways have been designed in • Planning
Transportation Projects: maintenance of GSI more funding than certain ways with expectations of . Capital
transportation funding is facilities as part of stormwater programs costs and purposes for decades.
leveraged to cost- integrated roadway and are generally more • Many roadways are in poor condition
effectively include programs. popular with the public. and there is not enough funding to fix
stormwater quality • Complete and green them all.
elements. streets may be more • GSI is perceived as an "added"cost
popular with the public which,could reduce the number of
than traditional car- roadways that can be maintained.
focused streets. • Transportation funding is often
• Green streets may be restricted to certain roadway
less expensive than construction elements.
traditional streets based
on a life cycle cost
analysis.
46
City of Cupertino GSI Plan
Section/Overview GSI Specifics Pros Cons Type of Funding
Alternative Compliance: Leveraging • Gives flexibility to site • Can be difficult to come up with viable • Planning
Allows developers the development activities GI systems in locations alternative locations for GSI • Capital
flexibility to build,or to build and maintain that optimize pollutant installations. • O&M
fund through payment of GSI systems. In lieu loading reduction and . Can be difficult to quantify how much
an in-lieu fee,off-site fees can be used by other benefits to the a developer should pay upfront for
stormwater treatment developers who would community. long-term maintenance costs that the
systems for regulated rather make a lump • Allows for off-site municipality will bear.
projects or set up credit sum payment and stormwater treatment • May require agencies to modify the
trading programs. quickly complete their when stormwater stormwater sections of their municipal
compliance management codes to allow for the creation and/or
requirements. Credit requirements can't be use of the desired options/programs.
trading programs can met within a regulated
incentivize non- project site.
regulated properties • An in-lieu fee and/or
to retrofit impervious credit trading system
surfaces. can be used to achieve
additional retrofits and
installation of GSI.
Existing Permittee Could be used to plan, Voter approval or new • GSI must compete with many other • Planning
Resources: Utilize design, build and/or revenue sources not municipal priorities and essential • Capital
general funds for GSI. maintain GSI. required. services. • O&M
• Normally not a viable option for
substantial GI implementation.
Long Term Debt: borrow Can borrow money • Well understood • Need a dedicated stream of revenue • Planning
money up-front against a from future revenues process of raising funds. to pay off debt. • Capital
dedicated stream of to construct GSI • Allows acceleration of • If the general fund is used,can put the
revenue projected over systems in the general fund at risk if jurisdiction
compliance deadlines the life of the program. present. improvements cannot make the payments,credit
rating will be downgraded jeopardizing
other programs.
47
City of Cupertino GSI Plan
Section/Overview GSI Specifics Pros Cons Type of Funding
Public-Private Can provide for the • Leverages public funds • Stormwater fee or other source of • Planning
Partnerships(P3s): design,construction while minimizing stable revenue over the life of the P3 • Capital
agreements or contracts and maintenance of impacts to a contract is required. • O&M
between a municipality GSI systems over a municipality's debt • Contracts out to the private sector the
and a private company to long period. capacity. construction and maintenance of GSI
perform specific tasks. Access to advanced systems, possibly removing some
technologies. municipal control.
• Improved asset
management.
• Draws on private sector
expertise and financing.
• Benefits local economic
development and
"green jobs."
• Relieves pressure on
internallocal
government resources.
Volunteer Programs: Use volunteer • A low-cost source of • Can be time intensive for staff to set • Planning
provide community- programs to help build labor. up and administer. • Capital
based volunteer labor for or maintain GSI . Educational program for • May not be dependable in the long • O&M
specific tasks. facilities. community. run
• Can build support for a • May result in loss of municipal control
stormwater fee or other depending on program specifics.
funding source.
48
City of Cupertino GSI Plan
6.6.2 Results
Using the methodology described above, a predicted redevelopment rate of 15 acres per year was
calculated for the City of Cupertino. "Best" estimates of the magnitude of land areas that is predicted to
be addressed by future GSI facilities by the 2020, 2030, and 2040 milestones were calculated using the
rate. "High" (i.e., 50%> "best") and "Low" (i.e., 50%< "best") estimates of future GSI implementation
were also calculated to provide a range of potential redevelopment levels and account for uncertainty in
the "Best" estimate. Figure 6-1 and Table 6-2 present the outputs of the analysis and represent the total
acreage known to be addressed by GSI in Cupertino through 2018, and the best estimate of the
cumulative land area that will be addressed in 2020(363 acres), 2030 (513 acres), and 2040 (663 acres)
by GSI on privately-and publicly-owned parcels in the City of Cupertino.
900
Reported Projected ti
800 ate
700
N\P a
600 eS `�
Ln
OJ 500
Q 400 Low ESUMate3
300
m 200
a�
Q 100
0
tiQ� ti tiQ�
'High estimate—projected from 150%of"Best Estimate;2Best estimate—rate of redevelopment based on 10-year average
(2008-2017);and'Low estimate—projected from 50%of"Best Estimate".The large increase in G51 in 2017-2018 was due to
the completion of the Apple Park Campus and surrounding buildings.
Figure 6-1 Existing and projected cumulative land area(acres)anticipated to be addressed via Green
Stormwater Infrastructure facilities installed via private redevelopment in the City of Cupertino by 2020,
2030,and 2040.
49
City of Cupertino GSI Plan
Table 6-2 Projected cumulative land area(acres)anticipated to be addressed via Green Stormwater
Infrastructure facilities via private redevelopment in the City of Cupertino by 2020,2030, and 2040.
Year Low' Best' High 3
Existing GSI4 - 333 -
2020 348 363 378
2030 423 513 603
2040 498 663 828
'Low estimate—projected from 50%of"Best Estimate';2Best estimate—rate of redevelopment based on 10-year average(2009-2018);and
3High estimate—projected from 150%of"Best Estimate";°Total area addressed by parcel-based redevelopment projects with GSI completed
through 2018(excludes non-jurisdictional and green street and regional projects).
Table 6-3 lists the impervious surface percentage for each land use class, based on impervious surface
coefficients typically utilized, and the estimated impervious surfaces that are predicted to be retrofitted
by 2020, 2030, and 2040 in the City via GSI implementation on private and public parcels: 275 acres by
2020, 431 acres by 2030 and 557 acres by 2040. Note that these predictions do not include impervious
surface that may be addressed by projects in the public right-of-way, and that these predictions have a
high level of uncertainty because future redevelopment rates may increase or decrease relative to the
historic development trends and staff knowledge that the rate for Cupertino was based on.Therefore,
actual impervious surface addressed by GSI by the various milestones may increase or decrease relative
to what is presented in Table 6-3.
50
City of Cupertino GSI Plan
Table 6-3 Actual(2002-2018)and predicted(2019-2O4O)extent of impervious surface retrofits via GSI implementation on privately-and publicly-owned parcels in the
City of Cupertino by 2020,2030,and 2040.
Retrofits via GSI Implementation
2002-2018 2019-2020 2021-2030 2031-2040 Total(2002-2040)
Previous Land Use of Area
Impervious a Total Impervious Total Impervious Total Impervious Total Total
Impervious Impervious
Area Area Area Area Area Area Area Area
(acres) (acres) (acres)c (acres) (acres) (acres) (acres) Area(acres) (acres) Area(acres)
Commercial 83% 26 22 1 0 45 37 99 83 171 142
Industrial 91% 189 172 0 0 25 23 4 4 219 199
Residential-High Density 82% 26 21 0 0 24 20 16 13 66 54
Residential-Low Density 47% 4 2 0 0 0 0 0 0 4 2
Retail 96% 58 55 3 2 78 75 27 26 166 159
Urban Parks 20% 0 0 0 0 0 0 3 1 3 1
Open Spaceb 1% 30 0 1 0 3 0 0 0 34 0
Totals 333 272 4 3 176 155 150 126
662 557
Cumulative d 333 272 337 275 512 431 662 557
a Source:Existing Land Use in 2005:Data for Bay Area Counties,Association of Bay Area Governments(ABAG),January 2006
b Development totals from 2002-2018 may include new development of open space and vacant properties.
The total area for 2019-2020 is based on facilities that are currently under construction or planned to occur prior to 2020 and not the Phase I redevelopment rate and may therefore deviate from the'Best'
acres presented for 2020 in Table 6-2.
'Totals in this table differ slightly from predictions presented in Table 6-2 due to the inclusion of entire parcels in this table,as opposed to more generic"land areas"projections presented in Table 6-2.
51
6.7 Project Tracking System
A required component of the GSI Plan is to develop a process for tracking and mapping completed
public and private GSI projects and making the information available to the public.The City will continue
to implement existing internal tracking procedures for processing public and private projects with GSI,
meeting MRP reporting requirements, and managing inspections of stormwater treatment facilities. In
addition, the City will provide data to SCVURPPP for countywide tracking of completed public and
private GSI projects.This countywide tracking tool can be used to document a project's pollutant
reduction performance as well as overall total progress toward city or county-level stormwater goals
6.7.1 City Project Tracking System (Regulated and GSI)
The City currently utilizes an internal tracking system to manage information about installed stormwater
treatment measures (including GSI), operation and maintenance (O&M) of public facilities, O&M
verification program inspections, and enforcement actions.The tracking system consists of a site specific
GIS layer for installed stormwater treatment measures, an internal database (CityWorks) for O&M of
public facilities, and a spreadsheet for installed LID O&M and enforcement actions on private property.
6.7.2 SCVURPPP Project Tracking System
SCVURPPP has developed a centralized, web-based data management system, with a connection to GIS
platforms,for tracking and mapping all GSI projects in the Santa Clara Valley.The GSI Database provides
a centralized, accessible platform for municipal staff to efficiently and securely collect, upload, and store
GSI project data, and enhances SCVURPPP's ability to efficiently and accurately calculate and report
water quality benefits associated with GSI projects. It also allows portions of the GSI project information
to be made publicly available.
City staff will collect and manage information on GSI projects locally using the data management
systems described above. City staff will directly enter project data into the SCVURPPP GSI Database on
an annual basis through a web-based data entry portal for individual projects or upload data for multiple
projects in batch using standardized formats.
52
City of Cupertino
Green Stormwater Infrastructure Plan
Appendix A
Prioritization Metrics for Scoring GSI Project Opportunities
Table A-1. Prioritization Metrics for LID Project Opportunities
Points Weighting
Parcel Land Use Schools/GolfCourses Park/Open Space Public Buildings Parking Lots
Impervious Area (%) X<40 40<_X<50 50<_X<60 60<_X<70 70<_X<80 80<_X< 100 2
Hydrologic Soil Group C/D B A
Slope(%) 10>X>5 5>_X>3 3>_X>2 2>_X>1 1>_X
Within flood-prone storm drain No Yes
catchments
Contains PCB Interest Areas None Moderate High 2
Within Priority Development
No Yes
Area
Co-located with another agency
No Yes
project
Above groundwater recharge 2
Augments water supply No Opportunity for area and not above
capture and use groundwater contamination
area
Water quality source control No Yes
Reestablishes natural hydrology No Yes
Creates or enhances habitat No Yes
Opportunities
r MTC
Community enhancement No for other Within DAC Concern
enhancements Community of C
A-1
Table A-2. Prioritization Metrics for Regional Stormwater Capture Project Opportunities
Points Weighting
Parcel Land Use Schools/Golf Public parking Lot Park/Open Space
Courses Buildings
Impervious Area (%) X<40 40<_X<50 50:5X<60 60<_X<70 70<_X<80 80<_X<100 2
Parcel Size(acres) 0.25<_X<0.5 0.5:5X< 1 1:5X<2 2:5X<3 3<_X<4 4<_X
Hydrologic Soil Group C/D B A
Slope(%) 10>X>5 5>_X>3 3>_X>2 2>_X>1 1>_X
Proximity to Storm Drain (feet) X> 1,000 1,000>_X>500 500>_X>200 200>_X
Within flood-prone storm drain No Yes
catchments
Contains PCB Interest Areas None Moderate High 2
Within Priority Development Area No Yes
Co-located with another agency No Yes
project
Above groundwater 2
Augments water supply No Opportunity for recharge area and not
capture and use above groundwater
contamination area
Water quality source control No Yes
Reestablishes natural hydrology No Yes
Creates or enhances habitat No Yes
Opportunities for
Within DAC or
C
Community enhancement No other
enhancements Community of Concern
A-2
Table A-3. Prioritization Metrics for Green Street Project Opportunities
Points Weighting
Imperviousness (%) X<40 40<_X<50 50<_X<60 60<_X<70 70<_X<80 80<_X<100 2
Hydrologic Soil Group C/D B A
Slope(%) 5>X>4 4>_X>3 3>_X>2 2>_X>1 1>_X>0
Within flood-prone
No Yes
storm drain catchments
Contains PCB Interest None Moderate High 2
Areas
Within Priority
No Yes
Development Area
Co-located with
No Yes
another agency project
Above groundwater recharge 2
Augments water supply No Opportunity for area and not above
capture and use groundwater contamination
area
Water quality source No Yes
control
Reestablishes natural No Yes
hydrology
Creates or enhances
No Yes
habitat
Community No Opportunities for Within DAC or MTC
enhancement other Community of Concern
enhancements
A-3
City of Cupertino
Green Stormwater Infrastructure Plan
Appendix B
City of Cupertino Street Segments and Parcels with
Opportunities for GSI
City of Cupertino
Potential Parcel-based G51 Opportunities
Parcel Information City Prioritization Criteria SWRP Project Scoring"
� � Y
Y
y Y T 0 2 0 y
0 O Q N ro N O w
Ov V1 0 E 0 N j M N K
Co-location with Co-location with v 3 a �° Y 0 o `^ c L > O
APN Owner Land Use 0 0 M v '^ a °' v z 0 f6 c
Special Area Public project i ° J
v 0 O v Q o v 3 � s v E I
0 a e 0 E O
_J E 0 a a c 0 0
-6 — y M u
N
0 v m y w 0
LL Q
36230098 City of Cupertino Park/Open 3 0 1 2 0 0 0 0 10 1 1 0 1 19
Space
35706018 City of Cupertino Park/Open 3 0 5 2 0 0 0 0 10 1 1 0 1 23
Space
36915002 City of Cupertino Park/Open 3 0 1 2 0 0 0 0 10 1 1 0 1 19
Space
32614005 City of Cupertino Park/Open 3 0 1 1 0 0 0 0 10 1 1 0 1 18
Space
32609071 City of Cupertino Public Homestead 4 6 1 4 0 0 0 0 10 1 1 0 1 28
Buildings
32649036 City of Cupertino Park/Open 3 0 1 2 0 10 0 0 10 1 1 0 1 29
Space
Citywide Parks
and Recreation
31631041 City of Cupertino Park/Open System Master3 0 1 2 0 0 0 5 10 1 1 0 1 24
Space Plan-Portal Park;
Bike Boulevard
Project
Citywide Parks
36904044 City of Cupertino Park/Open and Recreation 3 0 1 4 0 0 0 5 10 1 1 0 1 26
Space System Master
Plan-Wilson Park
Park/Open Jollyman Park
35925024 City of Cupertino Space pathway 3 0 1 3 0 0 0 5 10 1 1 0 1 25
installation
37523047 City of Cupertino Public Lawrence MittyBuildings Park 4 0 1 2 0 0 0 5 10 1 1 0 1 25
Mary Avenue
32627030 City of Cupertino Park/Open Space Rennovation and 3 8 1 2 0 0 0 5 10 1 1 0 1 32
Park
City of Cupertino GSI Plan-Appendix B 1 of 2
City of Cupertino
Potential Parcel-based GSI Opportunities
Public Mary Avenue
32606052 City of Cupertino Buildings Rennovation and 4 8 1 2 0 10 0 5 10 1 1 0 1 43
Park
Memorial Park
Renovation;
32629022 Cityof Cupertino Park/Open Stevens Creek
p S ace Heart of the City 4 6 1 3 0 0 5 5 10 1 1 P Blvd protected 0 1 37
bike lanes
(separated bike
Memorial Park
Renovation;
32629006 Cityof Cupertino Park/Open Stevens Creek
p S ace Heart of the City 3 0 1 3 0 0 5 5 10 1 1 p Blvd protected 0 1 30
bike lanes
(separated bike
S Foothill Blvd
and N Foothill
34215038 City of Cupertino Park/Open Blvd Green Street;
Space Citywide Parks 3 0 1 3 0 0 0 5 10 1 1 0 1 25
and Recreation
Master Plan
Blackberry Farm
Park/Open Retreat Center;
35710008 City of Cupertino Space Orange and Byrne 3 0 5 1 0 0 0 5 10 1 1 0 1 27
Avenue sidewalk
1 improvements
SWRP=Stormwater Resources Plan(SCVURPPP,2018).See Appendix A for prioritization metrics and scoring of GSI opportunities.
City of Cupertino GSI Plan-Appendix B
2 of 2
City of Cupertino
Potential Green Street Project Opportunities
Street Information City Prioritization Criteria SWRP Project Scoring'
y. N T
LCL
C
O a i u
I= 7 N
L L
Y
N +�+ a 71 y r y M V
a ?� M oc
a i L VI ai O1 -a y� N T = .+T+ G O
p 7 G C M 0 G Y �+ ._ ba H L V
p u Q CP L 7 O d
SWRP Co-location with Public Co-location with v t7 a c Q ._ o E '�^ ° M £ m Q
CL Project ID Street Name Jurisdiction project Special Area E ci c ° w Co r o cr u w > c o c O
J p Ln VI L6 Ln d d Q U Q Vf VI OC = W U W F
60501447 WHEATON DR CUPERTINO Bike Boulevard Project 6 1 5 0 0 5 5 10 1 1 1 1 36
60501446 WHEATON DR CUPERTINO Bike Boulevard Project 6 1 5 0 0 5 5 10 1 1 1 1 36
Citywide Parks and
60501557 WHEATON DR CUPERTINO Recreation System 4 1 5 0 0 5 5 10 1 1 1 1 34
Master Plan;Bike
Boulevard Project
60500926 BILICH Pl. CUPERTINO Bike Boulevard Project 4 1 5 0 0 5 5 10 1 1 1 1 34
60500612 S DE ANZA BLVD CUPERTINO Bike Boulevard Project South De Anza 10 1 5 0 0 5 5 10 1 1 1 1 40
60501621 BOLLINGER RD CUPERTINO Bike Boulevard Project 10 1 4 0 0 0 5 10 1 1 1 1 34
1000715919 CIVIK PARK LN CUPERTINO Bike Boulevard Project Heart of the City 8 1 1 0 0 5 5 10 1 1 1 1 34
60501804 RODRIGUES AVE CUPERTINO Bike Boulevard Project South De Anza 10 1 4 0 0 5 5 10 1 1 1 1 39
1000715916 TOWN CENTER LN CUPERTINO Bike Boulevard Project Heart of the City 6 1 4 0 0 5 5 10 1 1 1 1 35
60501620 BOLLINGER RD CUPERTINO Bike Boulevard Project 10 1 4 0 0 0 5 10 1 1 1 1 34
60502513 RODRIGUES AVE CUPERTINO Bike Boulevard Project South De Anza 10 1 4 0 0 5 5 10 1 1 1 1 39
60502170 N DE ANZA BLVD CUPERTINO Bike Boulevard Project North De Anza 6 1 5 0 0 5 5 10 1 1 1 1 36
60500883 INFINITE LOOP CUPERTINO Bike Boulevard Project North De Anza 6 1 3 0 0 5 5 10 1 1 1 1 34
60502172 N DE ANZA BLVD CUPERTINO Bike Boulevard Project North De Anza 6 1 3 0 0 5 5 10 1 1 1 1 34
60500901 MARYAVE CUPERTINO Bike Boulevard Project 8 1 4 0 10 0 5 10 1 1 1 1 42
60500368 DORADO CUPERTINO Bike Boulevard Project 4 1 2 0 10 0 5 10 1 1 1 1 36
60502363 MARY AVE CUPERTINO Bike Boulevard Project Heart of the City 6 1 4 0 0 5 5 10 1 1 1 1 35
60500370 MARY AVE CUPERTINO Bike Boulevard Project 6 1 4 0 10 0 5 10 1 1 1 1 40
60500369 MARY AVE CUPERTINO Bike Boulevard Project 6 1 4 0 10 0 5 10 1 1 1 1 40
City of Cupertino GSI Plan-Appendix B 1 of 7
City of Cupertino
Potential Green Street Project Opportunities
Street Information City Prioritization Criteria SWRP Project Scoring'
y. N T
LCL
C O a i u
E CD
N 7 N
L L
Y
N +�+ a W y r M y M V
U 0 V O � N 0 � U .0Y W
� ?�a M oc
a i L VI ai O1 -a y� N T = .+T+ G O
p 7 G C M O G Y �+ ._ ba
p u Q CP L 7 O d
SWRP Co-location with Public Co-location with v t7 a o Q = n o E '0 � M ° � E m Q
Project ID Street Name Jurisdiction project Special Area E L°n IA ,° 0 a a` Q U a H 3 Ln o°'c = LU U LU �
60500362 SEGOVIA CUPERTINO Bike Boulevard Project 6 1 4 0 10 0 5 10 1 1 1 1 40
60500367 DORADO CUPERTINO Bike Boulevard Project 6 1 3 0 10 0 5 10 1 1 1 1 39
60500902 METEOR DR CUPERTINO Bike Boulevard Project 8 1 4 0 10 0 5 10 1 1 1 1 42
60502362 PARKWOOD DR CUPERTINO Bike Boulevard Project Heart of the City 6 1 4 0 0 5 5 10 1 1 1 1 35
60502218 MILLARD LN CUPERTINO Bike Boulevard Project 6 1 5 0 10 0 5 10 1 1 1 1 41
60502720 PACIFICA RD CUPERTINO Bike Boulevard Project South De Anza 10 1 4 0 0 0 5 10 1 1 1 1 34
Memorial Park
Renovation;Stevens
60500741 MARY AVE CUPERTINO Creek Blvd protected bike Heart of the City 6 1 4 0 0 5 5 10 1 1 1 1 35
lanes(separated bike
lanes)
60500568 GRANADA AVE CUPERTINO Bike Boulevard Project Monta Vista Village 4 1 4 0 6 0 5 10 1 1 1 1 34
60501097 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 8 1 4 0 0 5 5 10 1 1 1 1 37
60501095 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 6 1 3 0 0 5 5 10 1 1 1 1 34
60501156 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 4 1 5 0 0 5 5 10 1 1 1 1 34
60501496 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 6 1 5 0 0 5 5 10 1 1 1 1 36
60501501 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 6 1 4 0 0 5 5 10 1 1 1 1 35
60SO0619 S STELLING RD CUPERTINO Bike Boulevard Project Heart of the City 6 1 3 0 0 5 5 10 1 1 1 1 34
60500096 N WOLFE RD CUPERTINO Bike Boulevard Project Heart of the City 10 1 4 0 0 5 5 10 1 1 1 1 39
60500913 SAICH WAY CUPERTINO Bike Boulevard Project Heart of the City 8 1 4 0 0 5 5 10 1 1 1 1 37
City of Cupertino GSI Plan-Appendix B 2 of 7
City of Cupertino
Potential Green Street Project Opportunities
Street Information City Prioritization Criteria SWRP Project Scoring'
y. N T
LCL
C O a i u
E CD
7 -6 0
N
in L
Y
U 0 LAV V O ?�N 0 U .0Y W
a M oc
a i L VI ai O1 -a y� N T x .+T+ G O
p 7 G C M O G Y �+ ._ ba
p u Q CP L 7 O d
SWRP Co-location with Public Co-location with v Q a o Q ._ n o E ;v '0 M ° E m Q
Project ID Street Name Jurisdiction project Special Area E c c 2 U u o co, VV a) T c o c O
1 1 p Ln in LL H a a Q V Q of 3 Ln oc x uw a LU F
60500623 S STELLING RD CUPERTINO Bike Boulevard Project Heart of the City 6 1 5 0 0 5 5 10 1 1 1 1 36
60501267 CAMPUS DR CUPERTINO Bike Boulevard Project Heart of the City 6 1 3 0 0 5 5 10 1 1 1 1 34
60501940 PENINSULA AVE CUPERTINO Bike Boulevard Project Monta Vista Village 8 1 4 0 10 0 5 10 1 1 1 1 42
60502506 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 8 1 4 0 0 5 5 10 1 1 1 1 37
60502021 S PORTAL AVE CUPERTINO Bike Boulevard Project Heart of the City 6 1 3 0 0 5 5 10 1 1 1 1 34
60500628 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 8 1 4 0 0 5 5 10 1 1 1 1 37
60502508 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 6 1 4 0 0 5 5 10 1 1 1 1 35
60501977 IMPERIAL AVE CUPERTINO Bike Boulevard Project Monta Vista Village 8 1 4 0 10 0 5 10 1 1 1 1 42
60500744 FINCH AVE CUPERTINO Bike Boulevard Project Heart of the City 8 1 4 0 0 5 5 10 1 1 1 1 37
60500443 N TANTAU AVE CUPERTINO Bike Boulevard Project Heart of the City 8 1 3 0 0 5 5 10 1 1 1 1 36
60SO1096 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 8 1 3 0 0 5 5 10 1 1 1 1 36
60501556 N PORTAL AVE CUPERTINO Bike Boulevard Project Heart of the City 6 1 4 0 0 5 5 10 1 1 1 1 35
60501525 N WOLFE RD CUPERTINO Bike Boulevard Project Heart of the City 10 1 4 0 0 5 5 10 1 1 1 1 39
60501507 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 10 1 4 0 0 5 5 10 1 1 1 1 39
60501508 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 10 1 4 0 0 5 5 10 1 1 1 1 39
60501509 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 8 1 5 0 0 5 5 10 1 1 1 1 38
60SO0889 SAICH WAY CUPERTINO Bike Boulevard Project Heart of the City 10 1 4 0 0 5 5 10 1 1 1 1 39
City of Cupertino GSI Plan-Appendix B 3 of 7
City of Cupertino
Potential Green Street Project Opportunities
Street Information City Prioritization Criteria SWRP Project Scoring'
y. N T
LCL
C O a i u
E CD
7 -6 0
N
in L
Y
LA V O N 0 U .0Y W
a ?� M oc
a i L VI ai O1 'O y� N T x .+T+ G O
O 7 O O r6 O G Y �+ ._ ba
O u Q CP L 7 O d
.i L H +' Vf M N O t6 V O V
SWRP Co-location with Public Co-location with v Q a o Q n o E '0 � M ° � E m Q
Project ID Street Name Jurisdiction project Special Area E c c ° u u o co, VV a) T c o c O
1 1 p Ln in LL H a a Q V Q of 3 Ln oc x uw a LU F
60501502 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 6 1 5 0 0 5 5 10 1 1 1 1 36
60501503 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 4 1 5 0 0 5 5 10 1 1 1 1 34
60502679 TORRE AVE CUPERTINO Bike Boulevard Project Heart of the City 8 1 4 0 0 5 5 10 1 1 1 1 37
60SO1494 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 6 1 5 0 0 5 5 10 1 1 1 1 36
60500105 E ESTATES DR CUPERTINO Bike Boulevard Project Heart of the City 8 1 5 0 0 5 5 10 1 1 1 1 38
60500206 PASADENA AVE CUPERTINO Bike Boulevard Project Monta Vista Village 8 1 4 0 10 0 5 10 1 1 1 1 42
60500097 N WOLFE RD CUPERTINO Bike Boulevard Project Heart of the City 8 1 4 0 0 5 5 10 1 1 1 1 37
60502335 TANTAU AVE CUPERTINO Bike Boulevard Project Heart of the City 10 1 4 0 0 5 5 10 1 1 1 1 39
60501500 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 6 1 4 0 0 5 5 10 1 1 1 1 35
60501571 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 8 1 4 0 0 5 5 10 1 1 1 1 37
60502035 BIANCHI WAY CUPERTINO Bike Boulevard Project Heart of the City 6 1 3 0 0 5 5 10 1 1 1 1 34
60502507 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 8 1 5 0 0 5 5 10 1 1 1 1 38
60502493 N BLANEY AVE CUPERTINO Bike Boulevard Project Heart of the City 8 1 3 0 0 5 5 10 1 1 1 1 36
60501217 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Monta Vista Village 8 1 3 0 10 0 5 10 1 1 1 1 41
60501524 MILLER AVE CUPERTINO Bike Boulevard Project Heart of the City 8 1 5 0 0 5 5 10 1 1 1 1 38
60500104 E ESTATES DR CUPERTINO Bike Boulevard Project Heart of the City 8 1 4 0 0 5 5 10 1 1 1 1 37
60500095 MILLER AVE CUPERTINO Bike Boulevard Project Heart of the City 8 1 5 0 0 5 5 10 1 1 1 1 38
City of Cupertino GSI Plan-Appendix B 4 of 7
City of Cupertino
Potential Green Street Project Opportunities
Street Information City Prioritization Criteria SWRP Project Scoring'
y. N T
LCL
C O a i u
E CD
7 -6 0
N
in L
Y
U 0 LAV V O ?�N 0 U .0Y W
a M oc
a i L VI ai O1 -a y� N T x .+T+ G O
p 7 G C M O G Y �+ ._ ba
p u Q CP L 7 O d
SWRP Co-location with Public Co-location with v Q a o Q ._ n o E '0 M ° E m Q
Project ID Street Name Jurisdiction project Special Area E c c ° u u o co, VV a) T c o c O
1 1 p Ln in LL H a a Q V Q of 3 Ln X x uw a LU
60502505 PORTAL PLZ CUPERTINO Bike Boulevard Project Heart of the City 6 1 4 0 0 5 5 10 1 1 1 1 35
60502197 STANTAUAVE CUPERTINO Bike Boulevard Project Heart of the City 8 1 5 0 0 5 5 10 1 1 1 1 38
60502331 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 10 1 5 0 0 5 5 10 1 1 1 1 40
60SO2367 VISTA DR CUPERTINO Bike Boulevard Project Heart of the City 6 1 3 0 0 5 5 10 1 1 1 1 34
60502180 CAMPUS DR CUPERTINO Bike Boulevard Project Heart of the City 6 1 4 0 0 5 5 10 1 1 1 1 35
60500666 BANDLEY DR CUPERTINO Bike Boulevard Project Heart of the City 8 1 3 0 0 5 5 10 1 1 1 1 36
60501504 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 4 1 5 0 0 5 5 10 1 1 1 1 34
60502755 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 8 1 4 0 0 5 5 10 1 1 1 1 37
60500745 FINCH AVE CUPERTINO Bike Boulevard Project Heart of the City 10 1 4 0 0 5 5 10 1 1 1 1 39
60500449 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Monta Vista Village 10 1 4 0 10 0 5 10 1 1 1 1 44
60SO2650 BANDLEY DR CUPERTINO Bike Boulevard Project North De Anza 6 1 3 0 0 5 5 10 1 1 1 1 34
60502179 CAMPUS DR CUPERTINO Bike Boulevard Project Heart of the City 6 1 4 0 0 5 5 10 1 1 1 1 35
605027S6 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 8 1 4 0 0 5 5 10 1 1 1 1 37
60501523 N WOLFE RD CUPERTINO Bike Boulevard Project 8 1 4 0 0 5 5 10 1 1 1 1 37
60502753 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 6 1 4 0 0 5 5 10 1 1 1 1 35
60501499 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 8 1 5 0 0 5 5 10 1 1 1 1 38
60501497 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 10 1 4 0 0 5 5 10 1 1 1 1 39
City of Cupertino GSI Plan-Appendix B 5 of 7
City of Cupertino
Potential Green Street Project Opportunities
Street Information City Prioritization Criteria SWRP Project Scoring'
y. N T
LCL
C O a i u
E CD
7 -6 0
N
L L
Y
U 0 V O � � ?�N 0 � U .0Y W
a M oc
a i L VI ai O1 'O y� N T = .+T+ G O
O 7 O O r6 O G Y �+ ._ ba
O u Q CP L 7 O d
.i L H +_' Vf M N O t6 N O u
SWRP Co-location with Public Co-location with v Q a o Q n o E ;an v '0 � M ° � E m Q
Project ID Street Name Jurisdiction project Special Area E L°n IA ,° 0 a a` Q u a H 3 Ln z = LU 0 0 U LU �
60502425 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Monta Vista Village 10 1 4 0 0 0 5 10 1 1 1 1 34
60500624 S STELLING RD CUPERTINO Bike Boulevard Project Heart of the City 8 1 4 0 0 5 5 10 1 1 1 1 37
60501506 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project 8 1 3 0 0 5 5 10 1 1 1 1 36
60501495 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 6 1 5 0 0 5 5 10 1 1 1 1 36
60501505 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project 8 1 5 0 0 5 5 10 1 1 1 1 38
60500740 MARY AVE CUPERTINO Bike Boulevard Project Heart of the City 6 1 3 0 0 5 5 10 1 1 1 1 34
60501093 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 8 1 2 0 0 5 5 10 1 1 1 1 35
60500618 5 STELLING RD CUPERTINO Bike Boulevard Project Heart of the City 8 1 4 0 0 5 5 10 1 1 1 1 37
60502509 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 6 1 4 0 0 5 5 10 1 1 1 1 35
60501094 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 6 1 4 0 0 5 5 10 1 1 1 1 35
60502328 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 10 1 5 0 0 5 5 10 1 1 1 1 40
60501252 N STELLING RD CUPERTINO Bike Boulevard Project Heart of the City 8 1 5 0 0 5 5 10 1 1 1 1 38
60502326 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 10 1 4 0 0 5 5 10 1 1 1 1 39
60501572 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 8 1 5 0 0 5 5 10 1 1 1 1 38
60500155 STEVENS CREEK BLVD CUPERTINO Bike Boulevard Project Heart of the City 10 1 3 0 0 5 5 10 1 1 1 1 38
Union Pacific RR Trail
Feasibility Study;
60500451 MC CLELLAN RD CUPERTINO McClellan Road Bike Monta Vista Village 8 1 1 0 10 0 5 10 1 1 1 1 39
Corridor(separated bike
lanes)
City of Cupertino GSI Plan-Appendix B 6 of 7
City of Cupertino
Potential Green Street Project Opportunities
Street Information City Prioritization Criteria SWRP Project Scoring'
y. N T
LCL
C O a i u
E CD7 N
L L
Y
N +�+ a 71 y rr y M V
0 U ° � � ?�N U � U .0Y LU
U
a M oc
SWRP Co-location with Public Co-location with t a c a Y o E '°^ ° M £ M a
CL Project ID Street Name Jurisdiction project Special Area E ° ° ° u Co o C °u w > c o c O
p Ln VI L6 Ln d d Q U Q Vf VI OC = W U W F
Citywide Parks and
60501944 BUBB RD CUPERTINO Recreation System Monta Vista Village 6 1 4 0 10 0 5 10 1 1 1 1 40
Master Plan;Bike
Boulevard Project
'SWRP=Stormwater Resources Plan(SCVURPPP,2018).See Appendix A for prioritization metrics and scoring of GSI opportunities.
City of Cupertino GSI Plan-Appendix B 7 of 7
City of Cupertino
Green Stormwater Infrastructure Plan
Appendix C
GSI concept for the Mary Avenue Greenbelt and Trail Project
MARY AVENUE GREEN STREET AN"
Cupertino
CONCEPT DESCRIPTION CONCEPT METRICS
Mary Avenue is an important connector road realized by creating a wide bioretention-enhanced WATERSHED CHARACTERISTICS
in the City of Cupertino that is at the hub of many green belt on the west side of the street containing Watershed
important destinations: Homestead High School, a pervious multi-use pathway to accommodate SUNNYVALE EAST CHANNEL
Dan Burnett bicycle-pedestrian bridge over 1-280, bicyclists, pedestrians, strollers, and joggers. Tree Drainage Management Area
Mary Avenue Dog Park, City of Cupertino Service wells will be installed every 100 feet on the east side 12.1 AC
Center, The Oaks shopping center, Cupertino of the street to treat stormwater and, along with new % Impervious of DMA
Senior Citizen Center, De Anza College, Memorial trees in the green beltway, eventually form an arbor 90
Park, and the commercial corridor on Stevens archway of green canopy over Mary Avenue. To Total Runoff Volume
Creek Blvd. The road has an 80-ft wide right-of-way create space for the proposed improvements, the 6.6 AC-FT/YR
with a variety of abutting land uses running 0.72 City plans to remove the center turn lane, convert
miles from Stevens Creek Blvd to 1-280. It presents 20'-wide angled parking on the west side to 7'- FACILITY INFORMATION
a tremendous opportunity for a "complete street" wide parallel parking, and incorporate the existing BIORETENTION
retrofit integrating stormwater management with bike lane on the west side into the green belt . A Total Facility Area
multiple community and environmental benefits. typical cross-section has been developed to show 23,958 SF
The City has been considering a complete street how the roadway could be reconfigured. Pervious Number of Facilities
concept on Mary Avenue for several years, with pavement will be employed in the roadway closer to 40
a vision of transforming the existing inefficient the Stevens Creek Blvd intersection where space Maximum Surface Ponding
roadway into a multi-functional corridor. is in higher demand. Bioretention has a 5% sizing 0.5 FT
Surveys have identified"trails and pathways"and ratio (based on available space and to achieve Storage Volume
"access to nature" as the top two most sought after better performance), and the pervious pavement 0.7 AC-FT
community benefits among Cupertino residents. has a 20% sizing ratio (4 parts run-on area to 1 PERVIOUS PAVEMENT
Stormwater, habitat, and community benefits will be part pervious pavement). Total Facility Area
9,583 SF
LOCATED IN PARKING LANE
Storage Volume
0.2 AC-FT
- -__= - DESIGN CRITERIA
Side-11, Angled Parking Drive Lane Drive Lane Parallel Parking Sidewalk
3' 1]' 20' 20' 11' S'
78, Total Storage
0.9 AC-FT
Infiltration Rate
0.2 IN/HR
- Total Runoff Captured
Greenbelt with Pervious Pathway Parallel Packing Drive Lane Drive Lane Bike Lane Parallel Parking Sidewalk 27' T 13' 3' 6.6 AC-FT/YR (100%)
~ 13' 10' 5' r
78'
Pre-construction(top) &Post-construction(bottom) Street Section
Preliminary concept for discussion purposes only 2-1
N
alit IV i
LU
1103
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I
5, p v
—w
m _ 0
ca � O
r a N
z Q> CD
f'
+lf ° Z O
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I r �
t• • c t �+ � O
U
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ME
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— E
r - lit
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-
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dal ID
Q a _ z
co
♦tt �_
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V
MARY AVENUE GREEN STREET
- 4x• r; f is� •- _:e,'• �'ti•� x' ,+X`.•:x :x. �L
�• ��t� �'ti7 i* 1, .: •ii o i ._'� icy s, � ��
`i ds �'� '•�ram,- .��� � � s � f_ i y I
LT
Exampleof Integrationof Bioretention with Bike and Pedestrian CrossingsLyon, ple of Stormwater / Multi-modal TransportationOptions IFrance
France
Preliminary concept for discussionp• only 2-3
BUDGET-LEVEL COST ESTIMATES
DESCRIPTION UNIT COST UNIT QUANTITY SUBTOTAL
Utilities Protection/Relocation $90,000 LS 1 $90,000
Demo,Excavation&Offhaul $10 SF 33,541 $335,400
Curb and 36"Sidewalls $185 LF 9,073 $1,678,600
Bio-soil Media $250 CY 1,331 $332,800
Pervious pavement $15 SF 9,583 $143,700
Underdrains $5 SF 33,541 $167,700
Drain Rock Subbase $150 CY 1,242 $186,300
Plantings&Mulch $22 SF 23,958 $527,100
Catch Basin Relocation $7,500 EA 11 $82,500
Storm Drain Connections $5,000 EA 20 $100,000
CONSTRUCTION SUBTOTAL $3,644,000
Mobilization(10%Construction) $364,000
Contingency(30%Construction) $1,093,000
Design(15%Total) $765,000
_ TOTAL PROJECT COST(DESIGN+CONSTRUCTION) $5,866,000
These are planning-level cost estimates($2018)for design and construction.Soft costs for City administration and project management and post-con-
struction operations and maintenance are not included.Other factors that may affect the cost of future construction include escalation and market
conditions.
This cost estimate only includes stormwater management components appropriately sized to treat runoff from the project area. The City of Cupertino
will procure additional funding for non-stormwater related components of the complete street retrofit.
CONCEPT EFFECTIVENESS (ANNUAL AVERAGE) ADDITIONAL POTENTIAL BENEFITS
Total 2.8
Sediment Reduced O WITHIN PRIORITY
(tons/yr) DEVELOPMENT AREA AUGMENTS WATER SUPPLY
0
Tota 1 6.6 0 0
Runoff Captured 1 3.5 T/R 0.010 . • , GROUNDWATER RECHARGE COMMUNITY ENHANCEMENT
(ac-ft/yr) ' ' (eioretention)
B +
^ ^^REESTABLISHES NATURAL
0% 20% 40% 60% 80% 100% HYDROLOGY
INF - Infiltration T/R -Treat& Release B - Bypass
Effectiveness is defined as the modeled ability of the proposed project to capture stormwater runoff from the management area,remove the identified
constituents from that stormwater,and infiltrate or reuse the captured water.
For planning purposes,recharge is approximated as being equivalent to infiltration if the project is located in the groundwater recharge zone.
Modeling and performance estimates are based on an historical rainfall time series from water year 2007 through water year 2015.
PAR D I G M Lotus Water
E N V I R ❑ N M E N T A L
Preliminary concept for discussion purposes only 2-4
ADDITIONAL CONSIDERATIONS
This project concept is planning-level and subject to revision as
additional information related to geotechnical, environmental,
and stakeholder considerations becomes available. Factors to
be considered include but are not limited to the following:
Infiltration Potential.The project is in a designated recharge area.
The map of Depth to First Groundwater for the Santa Clara Basin in
Appendix A of the SCVURPPP C.3 Stormwater Handbook shows depth
to groundwater as approximately 50 feet;therefore, no conflicts with
groundwater are anticipated.The NRCS SSURGO database lists soils
in the projects area as having an infiltration capacity of 0.20-0.57 in/
hr;facilities are assumed to require installation of an underdrained.
Undrained facilities are not lined and, therefore, a portion of the
stormwater entering the facility will infiltrate into underlying soil. Site-
specific infiltration tests should be performed during early design so that
facilities are adequately sized and drained.
Parking Analysis. Mary Avenue is currently used for all-day parking by
visitors, particularly DeAnza College students. Instituting metering or
parking permits would encourage students to park at the college,which
appears to have capacity but is not free of charge.
Utility Coordination.Additional spatial data showing all utility mains along
the roadway corridor should be collected and evaluated for potential
conflicts; proposed facility locations should be adjusted as necessary to
avoid any identified conflicts.
Historical Lead Contamination.There is historical lead contamination in
the landscape between Mary Avenue and Hwy 85. Lead was detected
above background levels and impacted soil off hauled for proper disposal
during construction of the Mary Avenue Dog Park.
Stakeholder Coordination. Outreach should be conducted to area
residents and others that may be affected by roadway configuration
changes and less on-street parking.
The Oaks shopping center at the intersection of Stevens Creek Blvd is
likely to be redeveloped in the coming years, and retrofit of its parking lot
area may provide an additional synergy opportunity.
Maintaining traffic flow and adequate parking while improving pedestrian
and bicycle safety will transform Mary Avenue into a critical link in
Cupertino's Safe Routes to School network.
Preliminary concept for discussion purposes only 2-5
City of Cupertino
Green Stormwater Infrastructure Plan
Appendix D
Guidance for Identifying Green Infrastructure Potential in
Municipal Capital Improvement Program Projects
BASMAA Development Committee
Guidance for Identifying Green Infrastructure Potential
in Municipal Capital Improvement Program Projects
May 6, 2016
Background
In the recently reissued Municipal Regional Stormwater Permit ("MRP 2.0"), Provision C.3.j.
requires Permittees to develop and implement Green Infrastructure Plans to reduce the adverse
water quality impacts of urbanization on receiving waters over the long term. Provisions C.11
and C.12 require the Permittees to reduce discharges of Mercury and PCBs, and portion of
these load reductions must be achieved by implementing Green Infrastructure. Specifically,
Permittees collectively must implement Green Infrastructure to reduce mercury loading by 48
grams/year and PCB loading by 120 grams/year by 2020, and plan for substantially larger
reductions in the following decades. Green Infrastructure on both public and private land will
help to meet these load reduction requirements, improve water quality, and provide multiple
other benefits as well. Implementation on private land is achieved by implementing stormwater
requirements for new development and redevelopment (Provision C.3.a. through Provision
C.31). These requirements were carried forward, largely unchanged, from MRP 1.0.
MRP 2.0 defines Green Infrastructure as:
Infrastructure that uses vegetation, soils, and natural processes to manage water and
create healthier urban environments. At the scale of a city or county, green
infrastructure refers to the patchwork of natural areas that provides habitat, flood
protection, cleaner air, and cleaner water. At the scale of a neighborhood or site, green
infrastructure refers to stormwater management systems that mimic nature by soaking
up and storing water.
In practical terms, most green infrastructure will take the form of diverting runoff from existing
streets, roofs, and parking lots to one of two stormwater management strategies:
1. Dispersal to vegetated areas, where sufficient landscaped area is available and slopes
are not too steep.
2. LID (bioretention and infiltration) facilities, built according to criteria similar to those
currently required for regulated private development and redevelopment projects under
Provision C.3.
In some cases, the use of tree-box-type biofilters may be appropriate'. In other cases, where
conditions are appropriate, existing impervious pavements may be removed and replaced with
pervious pavements.
In MRP 2.0, Provision C.3.j. includes requirements for Green Infrastructure planning and
implementation. Provision C.3.j. has two main elements to be implemented by municipalities:
1. Preparation of a Green Infrastructure Plan for the inclusion of LID drainage design into
storm drain infrastructure on public and private land, including streets, roads, storm
drains, etc.
2. Early implementation of green infrastructure projects ("no missed opportunities"),
This guidance addresses the second of these requirements. The intent of the "no missed
opportunities" requirement is to ensure that no major infrastructure project is built without
assessing the opportunity for incorporation of green infrastructure features.
Provision C.3.j.ii. requires that each Permittee prepare and maintain a list of green
infrastructure projects, public and private, that are already planned for implementation during
the permit term (not including C.3-regulated projects), and infrastructure projects planned for
1 Standard proprietary tree-box-type biofilters are considered to be non-LID treatment and will only be
allowed under certain circumstances. Guidance on use and sizing of these facilities will be provided in a
separate document.
1 5-6-16
implementation during the permit term that have potential for green infrastructure measures.
The list must be submitted with each Annual Report, including:
"... a summary of how each public infrastructure project with green infrastructure
potential will include green infrastructure measures to the maximum extent practical
during the permit term. For any public infrastructure project where implementation of
green infrastructure measures is not practicable, submit a brief description for the
project and the reasons green infrastructure measures were impracticable to
implement".
This requirement has no specified start date; "during the permit term"means beginning January
1, 2016 and before December 31, 2020. The first Annual Report submittal date will be September
30, 2016.
Note that this guidance primarily addresses the review of proposed or planned public projects
for green infrastructure opportunities. The Permittee may also be aware of proposed or planned
private projects, not subject to LID treatment requirements, that may have the opportunity to
incorporate green infrastructure. These should be addressed in the same way as planned
public projects, as described below.
Procedure for Review of Planned Public Projects and Annual Reporting
The municipality's Capital Improvement Program (CIP) project list provides a good starting
point for review of proposed public infrastructure projects. Review of other lists of public
infrastructure projects, such as those proposed within separately funded special districts (e.g.,
lighting and landscape districts, maintenance districts, and community facilities districts), may
also be appropriate. This section describes a two-part procedure for conducting the review.
Part 1 - Initial Screening
The first step in reviewing a CIP or other public project list is to screen out certain types of
projects from further consideration. For example, some projects (e.g., interior remodels, traffic
signal replacement) can be readily identified as having no green infrastructure potential. Other
projects may appear on the list with only a title, and it may be too early to identify whether
green infrastructure could be included. Still others have already progressed past the point
where the design can reasonably be changed (this will vary from project to project, depending
on available budget and schedule).
Some "projects" listed in a CIP may provide budget for multiple maintenance or minor
construction projects throughout the jurisdiction or a portion of the jurisdiction, such as a tree
planting program, curb and sidewalk repair/upgrade, or ADA curb/ramp compliance. It is
recommended that these types of projects not be included in the review process described
herein. The priority for incorporating green infrastructure into these types of projects needs to
be assessed as part of the Permittees'development of Green Infrastructure Plans, and standard
details and specifications need to be developed and adopted. During this permit term,
Permittees will evaluate select projects, project types, and/or groups of projects as case studies
and develop an approach as part of Green Infrastructure planning.
The projects removed through the initial screening process do not need to be reported to the
Water Board in the Permittee's Annual Report. However, the process should be documented
and records kept as to the reason the project was removed from further consideration. Note
that projects that were determined to be too early to assess will need to be reassessed during
the next fiscal year's review.
The following categories of projects may be screened out of the review process in a given fiscal
year:
1. Projects with No Potential - The project is identified in initial screening as having no
green infrastructure potential based on the type of project. For example, the project
does not include any exterior work. Attachment 1 provides a suggested list of such
projects that Permittees may use as a model for their own internal process.
2 5-6-16
2. Projects Too Early to Assess-There is not yet enough information to assess the
project for green infrastructure potential, or the project is not scheduled to begin design
within the permit term (January 2016- December 2020). If the project is scheduled to
begin within the permit term, an assessment will be conducted if and when the project
moves forward to conceptual design.
3. Projects Too Late to Change -The project is under construction or has moved to a
stage of design in which changes cannot be made. The stage of design at which it is too
late to incorporate green infrastructure measures varies with each project, so a
"percent-complete" threshold has not been defined. Some projects may have funding
tied to a particular conceptual design and changes cannot be made even early in the
design process, while others may have adequate budget and time within the
construction schedule to make changes late in the design process. Agencies will need to
make judgments on a case-by-case basis.
4. Projects Consisting of Maintenance or Minor Construction Work Orders-The
"project" includes budgets for multiple maintenance or minor construction work orders
throughout the jurisdiction or a portion of the jurisdiction. These types of projects will
not be individually reviewed for green infrastructure opportunity but will be considered
as part of a municipality's Green Infrastructure Plan.
Part 2 -Assessment of Green Infrastructure Potential
After the initial screening, the remaining projects either already include green infrastructure or
will need to go through an assessment process to determine whether or not there is potential to
incorporate green infrastructure. A recommended process for conducting the assessment is
provided later in this guidance. As a result of the assessment, the project will fall into one of
the following categories with associated annual reporting requirements. Attachment 2 provides
the relevant pages of the FY 15-16 Annual Report template for reference.
■ Project is a C.3-regulated project and will include LID treatment.
Reporting: Follow current C.3 guidance and report the project in Table C.3.b.iv.(2) of the
Annual Report for the fiscal year in which the project is approved.
■ Project already includes green infrastructure and is funded.
Reporting:List the project in "Table B-Planned Green Infrastructure Projects" in the
Annual Report, indicate the planning or implementation status, and describe the green
infrastructure measures to be included.
■ Project may have green infrastructure potential pending further assessment of
feasibility, incremental cost, and availability of funding.
Reporting:If the feasibility assessment is not complete and/or funding has not been
identified, list the project in "Table A-Public Projects Reviewed for Green Infrastructure"
in the Annual Report. In the "GI Included?" column, state either "TBD" (to be
determined) if the assessment is not complete, or "Yes" if it has been determined that
green infrastructure is feasible. In the rightmost column, describe the green
infrastructure measures considered and/or proposed, and note the funding and other
contingencies for inclusion of green infrastructure in the project. Once funding for the
project has been identified, the project should be moved to "Table B-Planned Green
Infrastructure Projects" in future Annual Reports.
■ Project does not have green infrastructure potential. A project-specific assessment
has been completed, and Green Infrastructure is impracticable.
Reporting:In the Annual Report, list the project in "Table A-Public Projects Reviewed for
Green Infrastructure". In the "GI Included?" column, state "No." Briefly state the
reasons for the determination in the rightmost column. Prepare more detailed
documentation of the reasons for the determination and keep it in the project files.
3 5-6-16
Process for Assessing Green Infrastructure Potential of a Public Infrastructure Project
Initial Assessment of Green Infrastructure Potential
Consider opportunities that may be associated with:
■ Alterations to roof drainage from existing buildings
■ New or replaced pavement or drainage structures (including gutters, inlets, or pipes)
■ Concrete work
■ Landscaping, including tree planting
■ Streetscape improvements and intersection improvements (other than signals)
Step 1: Information Collection/Reconnaissance
For projects that include alterations to building drainage, identify the locations of roof leaders
and downspouts, and where they discharge or where they are connected to storm drains.
For street and landscape projects:
■ Evaluate potential opportunities to substitute pervious pavements for impervious
pavements.
■ Identify and locate drainage structures, including storm drain inlets or catch basins.
■ Identify and locate drainage pathways, including curb and gutter.
Identify landscaped areas and paved areas that are adjacent to, or down gradient from, roofs or
pavement. These are potential facility locations. If there are any such locations, continue to the
next step. Note that the project area boundaries may be, but are not required to be, expanded
to include potential green infrastructure facilities.
Step 2: Preliminary Sizing and Drainage Analysis
Beginning with the potential LID facility locations that seem most feasible, identify possible
pathways to direct drainage from roofs and/or pavement to potential LID facility locations—by
sheet flow, valley gutters, trench drains, or (where gradients are steeper) via pipes, based on
existing grades and drainage patterns. Where existing grades constrain natural drainage to
potential facilities, the use of pumps may be considered (as a less preferable option).
Delineate (roughly) the drainage area tributary to each potential LID facility location. Typically,
this requires site reconnaissance, which may or may not include the use of a level to measure
relative elevations.
Use the following preliminary sizing factor (facility area/tributary area) for the potential facility
location and determine which of the following could be constructed within the existing right-of-
way or adjacent vacant land. Note that these sizing factors are guidelines (not strict rules, but
targets):
■ Sizing factor >_ 0.5 for dispersal to landscape or pervious pavement2 (i.e., a maximum
2:1 ratio of impervious area to pervious area)
■ Sizing factor >_ 0.04 for bioretention
■ Sizing factor >_ 0.004 (or less) for tree-box-type biofilters
For bioretention facilities requiring underdrains and tree-box-type biofilters, note if there are
potential connections from the underdrain to the storm drain system (typically 2.0 feet below
soil surface for bioretention facilities, and 3.5 feet below surface for tree-box-type biofilters).
2 Note that pervious pavement systems are typically designed to infiltrate only the rain falling on the
pervious pavement itself,with the allowance for small quantities of runoff from adjacent impervious
areas. If significant runoff from adjacent areas is anticipated, preliminary sizing considerations should
include evaluation of the depth of drain rock layer needed based on permeability of site soils.
4 5-6-16
If, in this step, you have confirmed there may be feasible potential facility locations, continue to
the next step.
Step 3: Barriers and Conflicts
Note that barriers and conflicts do not necessarily mean implementation is infeasible, however,
they need to be identified and taken into account in future decision-making, as they may affect
cost or public acceptance of the project.
Note issues such as:
■ Confirmed or potential conflicts with subsurface utilities
■ Known or unknown issues with property ownership, or need for acquisition or
easements
■ Availability of water supply for irrigation, or lack thereof
■ Extent to which green infrastructure is an "add on" vs. integrated with the rest of the
project
Step 4: Project Budget and Schedule
Consider sources of funding that may be available for green infrastructure. It is recognized that
lack of budget may be a serious constraint for the addition of green infrastructure in public
projects. For example, acquisition of additional right-of-way or easements for roadway projects
is not always possible. Short and long term maintenance costs also need to be considered, and
jurisdictions may not have a funding source for landscape maintenance, especially along
roadways. The objective of this process is to identify opportunities for green infrastructure, so
that if and when funding becomes available, implementation may be possible.
Note any constraints on the project schedule, such as a regulatory mandate to complete the
project by a specific date, grant requirements, etc., that could complicate aligning a separate
funding stream for the green infrastructure element. Consider whether cost savings could be
achieved by integrating the project with other planned projects, such as pedestrian or bicycle
safety improvement projects, street beautification, etc., if the schedule allows.
Step 5: Assessment—Does the Project Have Green Infrastructure Potential?
Consider the ancillary benefits of green infrastructure, including opportunities for improving
the quality of public spaces, providing parks and play areas, providing habitat, urban forestry,
mitigating heat island effects, aesthetics, and other valuable enhancements to quality of life.
Based on the information above, would it make sense to include green infrastructure into this
project—if funding were available for the potential incremental costs of including green
infrastructure in the project?Identify any additional conditions that would have to be met for
green infrastructure elements to be constructed consequent with the project.
5 5-6-16
Attachment 1
Examples of Projects with No Potential for Green Infrastructure
❑ Projects with no exterior work (e.g., interior remodels)
❑ Projects involving exterior building upgrades or equipment (e.g., HVAC, solar panels,
window replacement, roof repairs and maintenance)
❑ Projects related to development and/or continued funding of municipal programs or
related organizations
❑ Projects related to technical studies, mapping, aerial photography, surveying, database
development/upgrades, monitoring, training, or update of standard specs and details
❑ Construction of new streetlights, traffic signals or communication facilities
❑ Minor bridge and culvert repairs/replacement
❑ Non-stormwater utility projects (e.g., sewer or water main repairs/replacement, utility
undergrounding, treatment plant upgrades)
❑ Equipment purchase or maintenance (including vehicles, street or park furniture,
equipment for sports fields and golf courses, etc.)
❑ Irrigation system installation, upgrades or repairs
6 5-6-16
Attachment 2
Excerpts from the C.3 Section of the FY 15-16 Annual Report Template:
Tables for Reporting C.3-Regulated Projects and Green Infrastructure Projects
FY 2015-2016 Annual Report C.3—New Development and Redevelopment
Permittee Name:
C.3.b.iv.(2) ►Regulated Projects Reporting Table (part 1) -
Projects Approved During the Fiscal Year ReportingPeriod
Total Total Pre- Total Post-
Project Project Total Area of Total New Total Replaced Project Project
Name Location9, Project Project Type Site Land Impervious Impervious Impervious Impervious
Project Street Name of Phase & Project Area Disturbed Surface Surface Area Surface Surface
No. Address Developer No.10 Description" Watershed12 (Acres) (Acres) Area (ft2)13 (ft2)14 Area 15(ft2) Area 16(ft2)
Private
Projects
Public
Projects
Comments:
Guidance: If necessary, provide any additional details or clarifications needed about listed projects in this box. Do not leave any cells blank.
91nclude cross streets
101f a project is being constructed in phases,indicate the phase number and use a separate row entry for each phase. If not,enter"NA".
11Project Type is the type of development(i.e., new and/or redevelopment).Example descriptions of development are:5-story office building, residential with 160 single-family homes with five 4-story
buildings to contain 200 condominiums, 100 unit 2-story shopping mall, mixed use retail and residential development(apartments),industrial warehouse.
12State the watershed(s)in which the Regulated Project is located. Downstream watershed(s)may be included, but this is optional.
13All impervious surfaces added to any area of the site that was previously existing pervious surface.
14AII impervious surfaces added to any area of the site that was previously existing impervious surface.
15For redevelopment projects,state the pre-project impervious surface area.
16For redevelopment projects,state the post-project impervious surface area.
FY 15-16 AR Form 3-7 4/1/16
FY 2015-2016 Annual Report C.3—New Development and Redevelopment
Permittee Name:
C.3.b.iv.(2) ►Regulated Projects Reporting Table (part 2) - Projects Approved During the Fiscal Year
Reporting Period public projects
Project Date Operation &
Name Construction Source Treatment Maintenance Hydraulic Alternative
Project Approval Scheduled to Control Site Design Systems Responsibility Sizing Compliance Alternative HM
No. Date29 Begin Measures30 Measures31 Approved32 Mechanism33 Criteria34 Measures35/36 Certification37 Controls38/39
Public Projects
Comments:
Guidance: If necessary, provide any additional details or clarifications needed about listed projects in this box. Note that MRP Provision C.3.c.contains specific
requirements for LID site design and source control measures,as well as treatment measures,for all Regulated Projects. Entries in these columns should not be
"None" or"NA". Do not leave any cells blank.
29For public projects,enter the plans and specifications approval date.
301-ist source control measures approved for the project. Examples include: properly designed trash storage areas;storm drain stenciling or signage;efficient landscape irrigation systems;etc.
311-ist site design measures approved for the project. Examples include: minimize impervious surfaces;conserve natural areas,including existing trees or other vegetation,and soils;construct
sidewalks,walkways,and/or patios with permeable surfaces,etc.
32List all approved stormwater treatment system(s)to be installed onsite or at a joint stormwater treatment facility(e.g.,flow through planter, bioretention facility,infiltration basin,etc.).
331-ist the legal mechanism(s)(e.g., maintenance plan for O&M by public entity,etc...)that have been or will be used to assign responsibility for the maintenance of the post-construction stormwater
treatment systems.
34See Provision C.3.d.i."Numeric Sizing Criteria for Stormwater Treatment Systems"for list of hydraulic sizing design criteria.Enter the corresponding provision number of the appropriate criterion
(i.e., 1.a., 1.b.,2.a.,2.b.,2.c.,or 3).
35For Alternative Compliance at an offsite location in accordance with Provision C.3.e.i.(1),on a separate page,give a discussion of the alternative compliance site including the information specified
in Provision C.3.b.v.(1)(m)(i)for the offsite project.
35For Alternative Compliance by paying in-lieu fees in accordance with Provision C.3.e.i.(2),on a separate page, provide the information specified in Provision C.3.b.v.(1)(m)(ii)for the Regional
Project.
37Note whether a third party was used to certify the project design complies with Provision C.3.d.
381f HM control is not required,state why not.
391f HM control is required,state control method used(e.g.,method to design and size device(s)or method(s)used to meet the HM Standard,and description of device(s)or method(s)used,such as
detention basin(s),biodetention unit(s),regional detention basin,or in-stream control).
FY 15-16 AR Form 3-9 4/1/16
FY 2015-2016 Annual Report C.3—New Development and Redevelopment
Permittee Name:
C.3.j.ii.(2) ► Table A - Public Projects Reviewed for Green Infrastructure
Project Name and Project Description Status44 GI Description of GI Measures
Location43 Included?45 Considered and/or Proposed
or Why GI is Impracticable to Im lement46
EXAMPLE:Storm drain Installation of new storm Beginning planning TBD Bioretention cells(i.e., linear bulb-outs)will be
retrofit,Stockton and Taylor drain to accommodate the and design phase considered when street modification designs
10-yr storm event are incorporated
C.3.j.ii.(2) ► Table B - Planned Green Infrastructure Projects
Project Name and Project Description Planning or Green Infrastructure Measures Included
Location47 Implementation Status
EXAMPLE:Martha Gardens Retrofit of degraded Construction completed The project drains replaced concrete pavement and
Green Alleys Project pavement in urban October 17,2015 existing adjacent structures to a center strip of
alleyways lacking good pervious pavement and underlying infiltration trench.
drainage
43 List each public project that is going through your agency's process for identifying projects with green infrastructure potential.
44Indicate status of project,such as:beginning design, under design(or X%design), projected completion date,completed final design date,etc.
45 Enter"Yes"if project will include GI measures,"No"if GI measures are impracticable to implement,or"TBD"if this has not yet been determined.
46 Provide a summary of how each public infrastructure project with green infrastructure potential will include green infrastructure measures to the maximum extent practicable during
the permit term. If review of the project indicates that implementation of green infrastructure measures is not practicable,provide the reasons why green infrastructure measures
are impracticable to implement.
47 List each planned(and expected to be funded)public and private green infrastructure project that is not also a Regulated Project as defined in Provision C.3.b.ii. Note that funding
for green infrastructure components may be anticipated but is not guaranteed to be available or sufficient.
Fv 15-16 AR Form 3-13 4/1/16