Kitty Moore - 3-11-2018 9-56 a.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.
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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
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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).
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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)