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Kitty Moore - 3-12-2018 12-54 p.m. VallcowaterThe Vallco project would allegedly use recycled water. This would come from the Donald M Somers wastewater treatment plant up in Sunnyvale if the line was extended past Apple Campus 2's connection at the intersection of Homestead and Wolfe Rd. Apple kicked in over $4 million, and the other agencies put up $25 million to get the recycled line to their Apple Campus 2. We might think this recycled water comes free somehow, far from it, it is expensive to produce and it is subsidized, so while it costs more than 3 TIMES as much as potable water to produce, Sunnyvale however only charges 90% of their drinking water rate. Sunnyvale charges $3.95/hcf for their recycled water. This is advanced reverse osmosis tertiary treated water, and not cheap to make. Yes, we are glad it's not running into the bay, but do we need to subsidize Apple? And would it be better to use it for groundwater recharge which has also been proposed. The Vallco green roof would consume 80,369 gallons/day, that's 90.02 acre feet per year. This puts the not so green roof in 4th place for Sunnyvale's largest user water customers of their fancy state of the art recycled water. Behind Sunnyvale Golf Course (183.9 Acre feet/year), Moffet Field Golf Course (118.5 afy), and Baylands Park (95.5 afy) comes Vallco Green Roof at 90 afy. (An acre foot is an acre filled with water one foot deep. So 90 acres of water one foot deep.) Their water bill will be a whopping $154,677 per year. And we would be first subsidizing it, and then likely paying for it outright because, looking into the City of Cupertino's "Recreation, Parks, and Services Element, Chapter 9" of their Community Vision 2040 they state "if public parkland is not dedicated, require park fees based on a formula that considers the extent to which the publicly -accessible facilities meet community need." The plan even states "Design parks to utilize natural features and the topography of the site in order to protect natural features and keep maintenance costs low" and that parkland acquisition would be based on: "Retaining and restoring creeks and other natural open space areas." Further, the roof violates the city' own policies: Policy RPC -7.1: Sustainable Design Ensure that City facilities are sustainably designed to minimize impacts on the environment. Policy RPC -7.2: Flexibility Design facilities to be flexible to address changing community needs. Policy RPC -7.3: Maintenance Design facilities to reduce maintenance, and ensure that facilities are maintained and upgraded adequately Sustainable design/minimize impacts: The Vallco project scours the entire site and encases it in concrete, EDF 43 shows 400' of mature trees to be removed for lane widening on Wolfe Road to mitigate traffic. It is highly likely a bus pull out lane would require more mature trees be removed on Stevens Creek Blvd. for the 'mobility hub' or fancy bus stop located there. And because the northbound Wolfe Road lanes were reconfigured in the Vallco plan to be only 3 lanes, and the Apple buses use northbound Wolfe Rd. to access the I-280 southbound, it is likely the trees on the east side of Wolfe Rd. would need to be cut down to add a land for the on ramp. A sustainable design would reduce the amount of paved area and return it to a natural state. This was one of the arguments Apple Campus 2 made for removing of their sprawling buildings and parking lots. Flexibility Design: the project cannot be converted to sports fields etc. Maintenance: the project is as high maintenance as possible. http://www.cupertino.org[index.aspx?page=1275 The recycled water isn't cheap -- about $1,100 an acre-foot to produce, or roughly triple what it costs to buy water from the Delta, and this is a LOW ESTIMATE!! http://www.mercurynews.com/science/ci 26160300/california-drought-san-loses-new-high-tech-water http://sunnyvaIe.ca.gov/Portals/0/Sunnyvale/ESD/Water/Recycled%2OWater%2OExpansion%20Report/ Appl-ExistingRecycledWaterCustomers.pdf City of Sunnyuaie - Feasibility Study for Recycled Water Expansion Existing Recycled Water Customers Near -Term Demand Estimates 16539815 Pr- Sunnyvale Golf Course 605 Macara Av 3.5 183.9 164,140 Moffet Field Gulf Course 4.0 118.5 105,800 11005414 PF Santa Clara County - Sayfands Park 999 Caribbean Dr 47.0 95.5 85,200 11439401 PF Santa Clara County - Twin Creeks Sports Complex D 183 54.5 48,640 11001025 MPI Lockheed Missiles And Space Co Inc 1111 Lockheed Martin Wy 204.3 29.5 26,340 11445002 MPT Moffett Park Dr LIc 807 11th A Av 1.0 25.5 22,800 Moffat Field Site 25.4 22,740 110MO25 MPT Arden Realty Lp 1221 Crossman Av 15.5 25.3 22,640 110354D8 MPI Amb Property Lp 155 f Moffett Park Dr 21.0 22.6 20,240 11442468 MPT Menlo & Juniper Ntwrks Uc 1111 Lockheed Martin Wy 77.0 21.3 19,000 11032427 MPT Network Appliance Inc 1375 Crossman Av 1.1 17.6 15,740 20519002 Pf Sunnyvale City Of - Fair Oaks Park D Britton Av 13 17.4 15,640 11 1044M MPI Yahoo Ix 7D1 First Av 243 17.2 15,340 Green roof prediction calcs: 80,369 gallons/day = 0.24664307759536294 acre feet/day x 365 days/yr = 90.02 acre feet per year This means the green roof would be the 4t" largest recycled water user behind the Sunnyvale Golf Course, Moffet Field Golf Courxe, and Baylands Park (47 acres). Sunnyvale's discounted recycled water rates explained: "All agencies surveyed offer recycled water at discounted rates compared to potable water charges. Recycled water rates generally ranged from roughly 45% to 95% of potable rates. • The City of Sunnyvale's current recycled water rates are set at 90% of potable rates for both irrigation and industrial accounts. Compared to other agencies, Sunnyvale offers one of the smallest recycled water discounts on a percentage basis. Duration of Pricing Incentives To preserve future pricing flexibility, the City should not obligate itself to providing recycled water pricing discounts for perpetuity. For example, Redwood City's recycled water rate resolution only obligated the City to provide pricing discounts for a minimum of five years. Also, the City could opt to implement a higher discount for some time followed by a reduced discount (e.g. 40% discount for 5 years, then 25% discount thereafter). To date, the City has maintained the discounts for all recycled customers, regardless of when they originally connected. The City may need to charge different wholesale rates to different potential customers depending on various factors such as each customer's alternative cost of water, infrastructure funding requirements, and other considerations of both the City and the potential wholesale customer. For example, an agency with a severe water supply shortage facing costly supplemental supply alternatives would have a substantially higher "willingness to pay" than an agency with less-expensive potable water sources. " Sunnyvale charges $3.95/hcf convert to acre feet 435 hcf = 1 acre foot $3.95/hcf x 435 hcf/acre foot = $1,718.25/acre foot Vallco roof uses 90.02 acre-feet /year x $1,718.25/acre foot charged for recycled water = $154,677/year for recycled water for the roof. Recycled rate as % of potable rate is 90% DecemberRecycled Water Rate Survey - Patahle Recyded Recyded Rate % charge per hcf charge per hcf of Patab4 Rate city of sunrryvale Agritultur2 &.nstitu"nal $2.09 $1.88 9tl% _andsnpg2 Irrigation S4-38 S3-95 90% City of Redwood City Existing Irrigation ArMurltS Tier 1! Up to 10496 of water budget [most watersold in this tier) 54-78 53-59 75% Tier 2! From 141% - 24096 of aster budget $9-58 53-54 3796 (75% of Tier 1[ source: http://sunnyvale.ca.gov/Portals/0/Sunnyvale/ESD/Water/Recycled%20Water%2OExpansion%2OReport/AppF- TM_5RecycledWaterPricing.pdf We are in a drought, the San Jose Water Company last year imposed rate increases on anyone going over their 2013 water use and requested a 30% reduction in water use. All of this expense and effort just to get out of making a park? Next imagine the earthquake calculations for this elevated structure with trees on it. The costs to secure the structure go up. Sources: http://sunnyvale.ca.gov/Portals/0/Sunnyv... http://sunnyvaIe.ca.gov/PortaIs/0/S unnyv... Environmental Study provided by revitalizevallco.com water use as estimated by the water co. The following is from the Arborist report, of the Sand Hill/Vallco provided Environmental Study: 3.5 Ion Content in Recycled Water / Standards Many municipalities such as San Jose and Palo Alto are using recycled water as a regular component of their City parks irrigation regime. However, this does come with known drawbacks. Coast redwoods are known to be sensitive to ion concentrations in soil water per the text referenced below3. The text notes that coast redwood has low tolerance of boron ion in recycled water. Ion sensitivity of coast redwood as related to other ions such as sodium, chloride, or ammonium was not specifically noted in the text. However, per the author's conversations with numerous city arborists and consulting arborists in the Bay Area, coast redwood appears to have low tolerance of specific ionic content in water in addition to boron ion. The following table derived from information in the below -referenced text provides some guidelines for total ion content of various ions in recycled water at levels that could be deemed "safe" for trees with low tolerance (high ion sensitivity), although this is only a guideline, and was published more than 10 years ago: 3 Costello, Perry, Matheny, Henry, and Geisel (2003). Abiotic Disorders of Landscape Plants: A Diagnostic Guide. UC ANR Publication 3420. ANR Communications Services. Oakland, California. 13 of 42 Site Address: North Wolfe Road, Cupertino, CA Version: 2/11/2016 Walter Levison 2016 All Rights Reserved Registered Member, American Society of Consulting Arborists and Member of the International Society of Arboriculture Cell (415) 203-0990 / Email drtree@sbcglobal.net ASCA Registered Consulting Arborist #401 Qualified Tree Risk Assessor ISA Certified Arborist #WC -3172 Salinity tolerance of various tree species proposed in project tree palette by the landscape architect is noted in the reference shown in this report as citation #3. WLCA is in communication with the landscape architect staff to discuss salinity tolerance issues. EXISTING REDWOODS The new project does not propose to use recycled water for irrigation of the existing redwoods being retained as perimeter screening (personal communication 10/23/2015, property owner). Therefore, the ionic content of irrigation water appears (at the time of writing) to be an issue with new proposed tree plantings only. USE OF RECYCLED WATER BLEND AND FLUSHING SEQUENCES To reduce ion content in irrigation water to acceptable levels per the above matrix guidelines, recycled water with high ion content can be blended with standard municipal drinking water prior to running it through irrigation systems for surface application to trees. Per the property owner, this blending will be performed seasonally during non water -restriction periods in order to comply with local regulations regarding potable water use for landscapes during drought periods. Another "trick" that can be performed to reduce ionic content remaining in the root zones of trees is to use recycled water for a number of irrigation cycles (e.g. 4 to 9 cycles), then "flush" the root 14 of 42 Site Address: North Wolfe Road, Cupertino, CA Version: 2/11/2016 Unsafe for Tree Irrigation Water Ion Type of Content Range "Safe' Species with Low Measurement Considered Tolerance to Stated Ions TDS Total Dissolved Mg/I <450 450 to 2,OOD Solids Salinity F, mhos: cm <0.7 0.7 to 3.0 Boron rvlgh <0.5 0.5 to 1.0 Chloride (surface bubbler '-Igil <14D 14D to 300 irrigation) Chloride fog/I <100 >10D (sprinkler irrigatior : Sodium (surface bubbler SAR Q 3 to 9 irrigation) Sodium Mg/I <7D >70 (sprinkler irrigation) Salinity tolerance of various tree species proposed in project tree palette by the landscape architect is noted in the reference shown in this report as citation #3. WLCA is in communication with the landscape architect staff to discuss salinity tolerance issues. EXISTING REDWOODS The new project does not propose to use recycled water for irrigation of the existing redwoods being retained as perimeter screening (personal communication 10/23/2015, property owner). Therefore, the ionic content of irrigation water appears (at the time of writing) to be an issue with new proposed tree plantings only. USE OF RECYCLED WATER BLEND AND FLUSHING SEQUENCES To reduce ion content in irrigation water to acceptable levels per the above matrix guidelines, recycled water with high ion content can be blended with standard municipal drinking water prior to running it through irrigation systems for surface application to trees. Per the property owner, this blending will be performed seasonally during non water -restriction periods in order to comply with local regulations regarding potable water use for landscapes during drought periods. Another "trick" that can be performed to reduce ionic content remaining in the root zones of trees is to use recycled water for a number of irrigation cycles (e.g. 4 to 9 cycles), then "flush" the root 14 of 42 Site Address: North Wolfe Road, Cupertino, CA Version: 2/11/2016 Walter Levison 2016 All Rights Reserved Registered Member, American Society of Consulting Arborists and Member of the International Society of Arboriculture Cell (415) 203-0990 / Email drtree@sbcglobal.net ASCA Registered Consulting Arborist #401 Qualified Tree Risk Assessor ISA Certified Arborist #WC -3172 zones by using a 5th or 10th irrigation cycle of 100% municipal drinking water (anecdotal reference). This would require that a very detailed record of irrigation be maintained by a groundsperson on site, to record exactly when recycled water and drinking water was applied to very specific landscape zones. Both recycled water and drinking water would need to be available side by side as irrigation system inputs with manual levers that would be operated by the groundsperson. OAK TREES BEING INSTALLED Per discussions with arborist Dave Muffly who is an expert in oak tree selection and cultivation, oak species being installed at the project should be provided with municipal drinking water as the irrigation water source, without any blending with recycled water. This is recommended to avoid potential problems with ion sensitivity by the oaks. Mr. Muffly notes that an adjacent project will not use recycled water for irrigation of the oaks (this project is also within the jurisdiction of City of Cupertino, and has recycled water piping that will be used for irrigation of non -oak landscape zones). As regards the project roof planting area where many oak species will be installed, we may need to develop a special dual piping system which will allow for recycled water and standard drinking water sources to be piped up separately. This would allow the two water sources to be applied in an alternating manner and/or blended in a tank prior to being applied to sensitive species such as the oaks and fruit bearing orchard trees, to reduce the overall ionic content being applied to the landscape over time. WEEPING WILLOW AND FREMONT COTTONWOOD AT ROOF DRAINAGE SWALES The Abiotic Disorders text (citation #3) noted above in this report contains a list of various tree species along with referenced scientific studies during which salinity and boron tolerance was determined for certain species. Per this list, Fremont cottonwood, proposed to be installed at The Hills in swales where runoff collection will occur, exhibit "moderate" to "high" tolerance of salinity (i.e. ionic concentrations) in recycled water, which would suggest that they can tolerate soil moisture derived from runoff water that may contain higher than normal ionic concentration. Weeping willow, also proposed by the project team for inclusion in drainage runoff swales at our site, also appears to exhibit "moderate" to "high" tolerance of ionic concentration in irrigation water, which also suggests tolerance to runoff water as the main source of their root zone soil moisture. Even so, WLCA suggests considering removal of these two species from the proposed plant palette list, given that they require heavy irrigation year round to maintain vigor. RECYCLED WATER EFFECTS ON FRUIT -BEARING ORCHARD TREES Per the text referenced in citation #3 in this report, fruit -bearing tree species proposed by the team for the rooftop orchard which will be for human consumption are noted in the text as exhibiting "low" relative tolerance to ionic content in recycled water used for irrigation. Given that fruit bearing orchard trees generally require heavy irrigation, this is of concern if recycled water is going to be used on the project's greenroof where the orchard areas will be located. As noted above in this section of the report, blending recycled water with municipal drinking water can bring down ionic concentration to levels below the safe thresholds noted above in the matrix. Flushing the tree root zones by use of 100% drinking water on a periodic basis may also be a viable method of reducing ionic concentration buildup in the root zones of the trees, such as the example WLCA noted of 4 to 9 irrigation cycles using recycled water, followed by a 5th or a 10th irrigation cycle using 100% municipal drinking water (anecdotal reference). 15 of 42 Site Address: North Wolfe Road, Cupertino, CA Version: 2/11/2016 Walter Levison 2016 All Rights Reserved Registered Member, American Society of Consulting Arborists and Member of the International Society of Arboriculture Cell (415) 203-0990 / Email drtree@sbcglobal.net ASCA Registered Consulting Arborist #401 Qualified Tree Risk Assessor ISA Certified Arborist #WC -3172 Per the author's recent conversation with a Northern California soil scientist who specializes in orchard soils, the inability for fruit trees such as cherry, apricot and apple to tolerate ion content in recycled water used for irrigation appears to be verified. Blending and/or other dilution is warranted. Again, use of a dual piping system to bring up both standard drinking water and recycled water sources to the greenroof may be able to solve the problem of ionic content in recycled water being applied to the orchard areas, as it will allow us to blend the two sources of water and/or apply them to the landscape in an alternating manner to flush salts through the soil. WLCA suspects that over time, municipal recycled water may become of increasingly higher quality in terms of ionic content being reduced to below the low -tolerance sensitivity threshold of 0.7 Mmhos/cm salinity. Refer to the ionic content table on page 14 above for more information. (P 757-758 Environmental Study)