HomeMy WebLinkAbout2002-08-05 City CouncilCity of Palo Alto
TO:HONORABLE CITY COUNCIL
FROM:CITY MANAGER DEPARTMENT: UTILITIES
DATE:
SUBJECT:
AUGUST 5, 2002 CMR:297:,02
APPROVAL OF A RESOLUTION TO REVISE THE CITY OF PALO
ALTO LANDSCAPE WATER EFFICIENCY STANDARDS
RECOMMENDATION
Staff recommends Council amend the Palo Alto Municipal Code to adopt revised
Landscape Water Efficiency Standards.
BACKGROUND
The Landscape Water Efficiency Standards for the City of Palo Alto (Standards) were
adopted by Council in 1992, Ordinance 4106. The first revision was adopted by Council in
1993, Ordinance 4162. The Standards were developed in response to the State Water
Conservation in Landscaping Act, AB 325 (the Act) requiring that cities and counties adopt
an ordinance to address the efficient use of water in landscaping. As directed by the Act, the
State Department of Water Resources developed a model ordinance that incorporated the
best knowledge available at that time for water conservation in ornamental horticulture. In
consultation with local landscape architects and irrigation experts, staff adapted the State
model ordinance to the City of Palo Alto organization and local conditions. Utility Marketing
Services administers the Standards in conjunction with the Planning and Building Divisions
of the Department of Planning and Community Environment.
DISCUSSION
After nine years of experience in applying the Standards to landscape plans in Palo Alto, it
CMR:297:02 Page 1 of 3
has become apparent that another revision is necessary to add clarification’and enforcement
language.
¯The statement of applicability should state that City facilities are included.
’An exemption to the water budget requirement needs to be added for very small
landscaped areas of 1500 square feet or less. Installing a dedicated irrigation water
meter and associated irrigation circuits in very small areas has proved difficult for
landscape architects and is perceived as a burden by property owners. This exemption
is expected to decrease application processing time for smaller sites to help with
overall Building Division process streamlining.
¯Additional language to clarify water use calculations.for the amount of water needed
by trees would be helpful to landscape architects. Calculating the water use of trees
based only on the square feet of the planted area typically yields too small an amount
of water to maintain tree health. The proposed change will take into account the
amount of area covered by the tree canopy and yield a more accurate calculation of
tree water use.
Adding a Certificate of Substantial Completion would increase compliance with the
Standards. This would be signed by both the landscape architect and the installing
landscape contractor and submitted to the City. If the Certificate is not received
within 30 days of landscape installation by the Water-Gas-Wastewater Engineering
New Services office, the Utilities Department would send notices to the responsible
parties. A flow restrictor could be installed in the irrigation meter if there is no
response.
RESOURCE IMPACT
Resources for administering the Standards are included in the Utilities Department Operating
Budget and no additional funding is required. No new personnel are needed.
POLICY IMPLICATIONS
The adoption of these revised Standards does not represent any substantive change to existing
City policies. This recommendation is consistent with the Council approved Utilities
Strategic Plan Strategy 3: streamline and manage business processes to al!ow the City of Palo
Alto Utilities to work efficiently and cost-effectively.
CMR:297:02 Page 2 of 3
ENVIRONMENTAL REVIEW
Adoption of these Standards does not constitute a project for the purposes of the California
Environmental Quality Act.
ATTACHMENTS
A:Revised Landscape Water Efficiency Standards for the City of Palo Alto.
B:Resolution
PREPARED BY:
DEPARTMENT HEAD:
CITY MANAGER APPROVAL:
Beth O’Connor, Marketing Specialist
¯ ~aTt~r of Uti!ities
EMILtY HARRISON-’v
Assistant City Manager
CMR:297:02 Page 3 of 3
¯ LANDSCAPE WATER EFFICIENCY
STANDARDS
FOR THE
CITY OF PALO ALTO
IN COMPLIANCE WITH THE
STATE OF CALIFORNIA
WATER CONSERVATION
IN LANDSCAPING ACT
AB 325
Developed by the City of Palo Alto
Department of Utilities, Utility Marketing Services
in cooperation with the
Department of Planning and Community Environment
August 2002
TABLE OF CONTENTS
II.
III.
IV.
VII
Purpose ..............................................1
Applicability ............................’ ............. .. 1
Definitions ............................................1
Calculation of Maximum Water Allowance ...................4
Requirements for Landscape Plans... . .....................5
A. Planting Design Plan ....................., ............5
B. Grading Design Plan ...................................8
C.. Irrigation Design Plan .................., ...............9
D. Maintenance Specifications ............................16
Alternative Equipment or Design ..........................18
Water Use Monitoring ....................................18
Appendix 1: Landscape Water Use Statement .....................20
Appendix 2: Sample Statement of Design Intent ...................21
Appendix 3: Water Use Calculations and Worksheet ................22
Table 1: Landscape Coefficients ...........................25
Table 2: Design Efficiency ................................26
Appendix 4: Landscapes with Treated Groundwater
Irrigation Systems .................................27
Appendix 5: Certification of Substantial Completion .................28
II.
III.
Purpose
CITY OF PALO ALTO
LANDSCAPE STANDARDS
The purpose of these standards is to promote efficient water use through landscape design
and irrigation management appropriate to Palo Alto’s climate zone.
Applicability
A.The standards apply to new and rehabilitated industrial, commercial, institutional
and City facility landscaping over 1,500 square feet in size and all new Or
rehabilitated multi-family common areas over 1,500 square feet in size.
Single-family homes and multi-family private areas are exempt from these
standards. However,. all residents are encouraged to follow them.
The standards do not apply to cemeteries or registered historical sites. However,
landscape managers at these sites are encouraged to follow efficient irrigation
system management practices as shown in Section V.C.2.
Do The standards do not apply to any landscaping irrigated solely by reclaimed water
and to which there is no pipeline installed to deliver potable City water, or, for
which a Reclaimed Water Landscape Plan is submitted with the application for
review by the Architectural Review Board or the application for a Building
permit. See Appendix 4 for plan requirements.
School yards, parks, playgrounds, sports fields, and golf courses are exempt fi:om
a maximum water allowance. Every other requirement of these standards is
applicable, including estimation of irrigation water requirements. In addition, turf
areas of these sites will have a landscape irrigation audit performed after the
installation or renovation of the irrigation system. ¯
Definitions
The terms used in this document have the meaning set forth below:
CCF
One hundred cubic feet. The unit in which metered water is commonly
¯ measured. One CCF equals 748 gallons.
Common areas
Those areas in a residential development maintained by either the developer or a
homeowner’s association. ’
Conversion factor (0.00083)
The number that converts CCF units f~om inches per square foot’to units of one
hundred cubic feet (CCR) per square foot. Water is measured and sold in Palo
Alto in CCF units.
The conversion factor is calculated as follows:.
Conversion Factor = 1/(100xft3 x (12 in./ft.)) --.00083/in.ft2
Where in. = inches
ft. = feet
Circuit
A group of any type of emitters intercorme6ted with pipe and controlled by one
valve.
Effective Precipitation
The portion of total precipitation that is used by plants in the landscape..
Precipitation is not a reliable source of water but can contribute in some degree
toward the water needs of the landscape.
Estimated Applied Water
That portion of total water used in a landscape to be supplied by the City metered
water supply. The estimated applied water may not exceed the maximum water
allowance specified in Section IV. The. Water Use Calculations form in Appendix
3 indicates one methodology acceptable for the purposes of conforming to these
standards.
ET Adjustment Factor
A factor of .8, that when.applied to reference evapotranspiration, adjusts plant
water requirements based on an average of plant water requirements and irrigation
system efficiency.
Eto .
See Reference Evapotranspiration
Hydrozone
A portion of the landscaped area having plants with similar water needs in a
similar microclimate It may be served by one or more valves. A hydrozone may
be irrigated or non-irrigated. For example, a naturalized area planted with native
vegetation that will not need supplemental irrigation once established is a non-
irrigated hydrozone.
Irrigation Efficiency
A measurement of the amount of water beneficially used divided by the amount of
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water applied. Irrigation efficiency is derived from estimates of irrigation system
design and management practices.
Irrigation Valve
The device that regulates water flow in an individual circuit. A valve is opened or
closed by electric signals from the controller.
Irrigation Zone
Usually the same as irrigation circuit. An irrigation distribution line and
associated application devices controlled by one valve. A hydrozone may be large
enough to need more than one circuit.
Irrigation Zone Water Requirement
The plant water requirement of an irrigation zone or circuit divided by the
estimated design efficiency of the. type and configuration of application devices in
that zone. The result is expressed in CCF. Table 2 in Appendix 3 lists design
efficiencies acceptable for conforming to the Landscape Standards.
Landscaped Area
The parcel minus building pad(s), driveways, parking areas, impervious
hardscapes such as decks and patios, and other no-porous surfaces. Examples of
landscaped areas could include: plant areas, water bodies, porous walkways or
percolation areas and natural areas. A natural area is one occupied by mature
plants, native or acclimated, growing on undisturbed grades that are not irrigated.
Landscape Coefficient
A factor derived from analysis of plant species, planting [lensity, and microclimate
which, when compared to ETo results in an estimate of the amount of water
required to maintain a planted area.
Table 1 in Appendix.3 lists numeric values developed through research done by
Cooperative Extension, University of California, and others which are acceptable
for the purposes of the Landsdape Standards.
Local Annual Mean Precipitation
The average amount of rain per year based on an average of annual rainfall over a
30-year period, in inches. The 30-year average for Palo Alto may be obtained
from: Department of Utilities
Utility Marketing Services
250 Hamilton Avenue
Palo Alto, CA 94301Maximum Water Allowance
For design purposes, the upper limit of annual water use for the landscaped area
after the plant establishment period which may be supplied through City water
meters as specified by the formula in Section IV.
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Plant Water Requirement
An estimate of the amount of water required to maintain an acceptable degree of
health and vigor in the planting or group of plants irrigated by one valve.
Reference E,capotranspiration (ETo)
Standard measurement of environmental parameters that effect the water use of
plants. EToiS measured in inches per day, month, or year and is derived from
measurements of evapotranspiration from a test plot of four to geven-inch tall turf
in an open field that is well watered.
Total Water Use
The sum of water from the City metered water supply and also from effective
precipitation estimated to be used for a landscape.
IV.Calculation of Maximum Water Allowance
io Maximum Water Allowance
A Maximum Water Allowance (MWA) will be established for each site submitted
for review:
MWA = ETo x 0.8 x LAx 0.00083
Where!MWA = Maximum Water Allowance in CCF
ETo = Annual Reference Evapotranspiration in inches for Palo Alto
0.8 = 80 % of local ET
LA = Landscaped area in square feet
0.00083 = Conversion factor into CCF per square foot
Example for a site with one acre (43,560 sq. ft.) of landscaping:
MWA = 43.1 x0.8 x 43560 x 0.00083
MWA = 1247 CCF annual water allowance.
The MWA will be itemized on a Landscape Water Use Statement form provided
by the City. See Appendix 1 for a sample form.Note: For the purposes of these
standards, the annual ETo for PaloAlto may be considered to be 43.1.
inches/square foot/year.
Effective Precipitation
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It is understood that rainfall may provide some or all of landscape water
requirements during some winter months in Pal0 Alto’s climate zone. At the
option of the landscape architect or irrigation designer, landscape water use
calculations may include up to 25% of the local annual mean precipitation. This
percentage shall be referred to as "effective precipitation."
All provisions of Section VII, Water Use Monitoring, shall apply to the metered
water use of landscape water accounts whether effective precipitation is included
in the landscape water use calculations or not.
Requirements for Landscape Plans
A.Planting Design Plan
I.Landscape Design Requirements
a.Plant Selection and Grouping
i. Any plants may be used in the landscape, provided the total
metered water use does not exceed the maximum landscape water
allowance plus allowable effective precipitation and that the plants
meet the specifications set forth in Sections ii. And iii. below.
Table 1 in Appendix 3 provides values that may be used to derive
estimated water use for various types of landscaped areas.
ii. Plants having similar water use shall be grouped together in
distinct hydrozones.
iii. Plants Shal~ be selected appropriately based upon their
adaptability to the climatic, geologic, and topographical conditions
of the site. Protection and preservation of native species and
natural areas is encouraged.iv. The plant establishment period is
Considered to be 18 months for the purposes of these standards.
Landscapes may require more irrigation than the maximum water
-allowance during the first 18 months after planting.
b.Water Features
i. Water features, such as fountains, waterfalls, ornamental pools,
etc., shall be supplied by the irrigatipn service.
ii. Water needed to maintain levels in water features shall be
calculated in CCF and included as part of the’maximum landscape
water allowance. Make up water may be calculated at 100% ET of
the surface area of the water feature.
iii. Fountains or other types of decorative water bodies where
water is sprayed into the air are discouraged. Misting will not be
allowed. Any water feature submitted for review shall be designed
to minimize evaporation.
iv. Recirculating water shall be used for any water featttre.
v. Use of reclaimed water for fountains and water features is
encouraged. Reclaimed water used in this way need not be
included in calculation of the maximum landscape water
allowance.
vi. Refilling of all fountains and/or other types of decorative water
bodies with potable water may be prohibited during a City-
Council-declared water emergency.
Horticultural Soils Analysis
i. For projects with a landscaped area greater than 44,000 square
feet, a basic soil chemistry analysis or horticultural suitability
analysis from a laboratory specializing in landscape soils is
required. The soil analysis shall be made for approved projects
after rough grading is completed. If soil is imported for use in the
landscaped area, an analysis shall be submitted from each different
source of origin of that fill material. Samples will be selected for
analysis from each different soil type area of the project.
Final inspections of the project will not be completed without
receipt of the soils test report. The requirement for the soils
test shall be stated in the planting specifications.
ii. Soil will be amended according to the soil test report
recommendations
Documents to be submitted for Planting Plan Review
a.Statement of Design Intent
Each landscape plan submitted for review shall be accompanied by
6
No
a Statement of Design Intent. This statement shall consist of 1) a
brief statement.of the design concept and description of the project
at maturity, 2) a description of the irrigation of the proposed
project describing how the system conforms to Palo Alto=s
irrigation design requirements, and 3) a summary of the projected
long range maintenance of the project until maturity.
Landscape Planting Nan
The planting plan shall be drawn on project base sheets at a scale
that accurately and Clearly identifies:
i. All hydrozones. These must be clearly marked on the plans
and listed in the Water use Calculations chart. See page 23.
It may be necessary to make an additional plan sheet of the
planting plan and draw a bubble diagram of the hydrozones.
ii. Landscape materials, trees, hhrubs, ground cover, turf, and
other vegetation. Planting symbols shall be clearly drawn and
plants labeled by botanical name, common name, container size,
spacing, and quantities of each group of plants indicated.
iii.Property lines and street names.
iv.Streets, driveways, walkways, and other paved areas.
v.Pools, ponds, water features, fences and retaining walls.
vi. Existing and proposed buildings and Structures including
elevation, if applicable.
vii. Natural features including, but not limited to, rock
outcroppings, existing trees, and shrubs that will remain.viii.
Location, size, and species of existing street trees.
ix.Spot elevations used in making the grading plan.
x. A calculation of the total landscaped area in square feet.
Planting Trees in Turf
Trees may not be planted in turf unless surrounded by a mulched
area of a diameter equal to the diameter of the proj ected median-
life crown drip line.
7
If trees are specified in turf, this requirement for the mulched
area must be stated in the planting specifications.
Planting Specifications and Details
Planting specifications shall include details of tree staking and
plant installation, soil preparation details, and any other applicable
planting and installation details. These specifications must include
the following:
. A minimum of 2 inches of mulch shall be added in non-turf areas
to soil surface after planting except for areas planted with a non-
turf ground cover which shall have a minimum of 1 inch of mulch
added to the soil surface. Visqueen, sheet plastic, and other non-
porous material shall not be placed under the mulch. Porous
weed-barrier fabrics are acceptable.
The City wishes to reduce green waste additions to our landfill
facility. Therefore, the use of compost rather than redwood
products for mulch is recommended.
Co
Grading Design Plan
Grading design plans satisfying .the following conditions shall be submitted with
the documents for landscape review:-
A grading design plan shall be drawn on project base sheets on the same
scale as the landscape planting plan. It should be separate from, but use
the same format as, the landscape planting plan.
The grading design plan shall indicate finished configurations and
elevations of the landscaped area, including the height of graded slopes,
drainage patterns, pad elevations, and finish grade.
Irrigation Design Plan
1.Irrigation Design Plan Requirements
ao Maximum Water Allowance
A maximum water allowance shall be established for new projects.
See the Landscape Water Use Statement in Appendix 1.
b.Unified Plumbing Code and City of Palo Alto Standards
Co
Specifications for irrigation systems shall ensure that all
requirements of the adopted unified plumbing code are met. Plan
details shall be according to the Utilities Standards and the
Department of Public Works Standard Drawings and
Specifications.
These documents may be obtained from the City’s Department of
Public Works at either the Civic Center, 250 Hamilton Avenue,
Palo Alto, or the City’s Development Center at 285 Hamilton
Avenue, Palo Alto.
Water Meters
A separate water meter shall be installed to irrigate each approved
landscape. This meter shall be designated as an irrigation account
and no other utilities will be billed on such accounts.
d.Backflow Prevention
The irrigation system shall be separated from the City of Palo Alto
water.supply by a backflow prevention device or devices approved
by the City Utilities Department. A list of approved devices is in
the Utility Standards for Water-Gas-Wastewater. These standards
are $12.00 per copy. The fee maybe paid at the Revenue
Collections desk at the Palo Alto Civic Center at 250 Hamilton
Avenue. The Standards may be pickedup at the Utility
Engineering office at 1007 Elwell Court in Palo Alto.
Soil-Water Relationships
Soil types and infiltration rates shall be considered when designing
irrigation systems. All irrigation systems shall be designed to
avoid runoff, low head drainage, overspray, or other similar
conditions where water flows onto adjacent property, non-irrigated
ar.eas, walks, roadways, or structures. Proper irrigation equipment
shall be used to closely match application rates to infiltration rates
thereby minimizing runoff and overspray.
£Water Features
All water features will be supplied by the irrigation supply line.
go
Water used in the water feature must be included’in the Estimated
Non-irrigation Landscape Water Requirement.
Irrigation service for plant materials in containers shall be
connected to the automatic irrigation system.
Irrigation Zones
Irrigation zones shall have the following characteristics:
i. All piants shall have approximately similar water requirements.
ii. Irrigation zones shall encompass only one microclimate.
iii. All application devices shall have matched precipitation and
distribution tmiformity.
Irrigation Equipment-
Irrigation system components shall be selected on the basis that
they are appropriate for the task. Criteria shall include
performance, ease of maintenance, and public safety.
Sprinklers
All sprinklers f6rturf (microsprays, sprayheads, rotors, etc.) shall
have spring retracted pop-up operation with flexil~le connections to
piping. Sprinklers shall be selected and spaced for maximum
distribution uniformity.
If sprinklers are specified for areas less than eight (8) feet wide, a
written water efficiency statement must be a) submitted for review
or b) printed in the irrigation details. The statement must describe
how the chosen sprinklers will control or eliminate overspray
and/or runoff.
It is recommended that pop-up nozzles in turf be at least four (4)
inches high to allow water to spray over turf up to three (3) inches
tall.
Drip Systems
Drip systems shall be designed to provide water uniformly to the
area of a mature rootzone. Drip systems shall use PVC lateral
piping below grade for primary distribution of water to emitters or
groups of emitters. Secondary distribution lines may be of other
10
materials.
1.Drip Irrigation Circuits
Drip irrigation circuits shall be controlled by electric solenoid
valves capable of functioning in low-flow conditions as applicable
to the circuit being designed.
Each drip circuit will have a serviceable filter and valve capable of
flushing the drip laterals.
m.Irrigation Controllers
Electronic controllers shall be required for all projects. They shall
be capable of managing all aspects of the irrigation system design.
Minimum controller requirements are as follows:
i. Precise individual station timing.
ii. Runtime capabilities for extremes in precipitation rates.
iii.At least one program for each hydrozone and microclimate.
iv,Sufficient multiple cycles to avoid runoff.
v.Extended day calendar for deep-rooted plants.
vi.Power failure backup for all programs.
n.Anti-Drain Valves
The irrigation system shall be designed to prevent gravity drainage
of water through application devices. Two anti-drain valves which
are available are in-line check valves for lateral piping, or in-head
check valves to prevent low head drainage.
Anti-drain valves are not required for valves serving drip emitter
lines.
o.Rain Sensing Devices
Irrigation systems shall be equipped with rain sensing devices to
prevent irrigation during rainy weather. Soil moisture sensors shall
not be used as rain sensing devices.
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p.Pressure Gauge at Valve
Although not required, it is strongly advised to install a pressure
gauge Valve at each electric control valve (e.g. Schrader Valve) for
measuring circuit pressure during operation. This valve may be an
integral part of the electric control valve or may be tapped into a
pvc fitting downstream of the electric control valve.
q.Master Valve
A master valve shall be installed in the main line on the discharge
side of the back flow prevention.device.
Tree Irrigation
a.Separate circuit for Trees
bo
Trees will be irrigated by a dedicated circuit which shall be
separate from all other circuits and served by separate valves. This
applies to trees planted in mixed planting areas of shrubs and!or
ground cover and also to trees gurrounded by mulch or hard scape.
Calculating Water Use
i. Trees surrounded by mulch and/or hardscape:
The square footage area under each tree will be determined
according to.the best available information for thediameter of the
projected median-life crown drip line.,The landscape coefficient
will be calculated as usual according to the species and
microclimate, with an assumption of a density_factor of 1.0.
The total square footage for whatever number of trees are on that
valve will be used to calculate the water requirement for that valve
circuit according to the formula in the Standards. For water use
calculations purposes, including this square foot area under the
trees is likely to increase the total landscaped area of the project.
ii. Trees planted in mixed tree-shrub-groundcover areas:
The square footage of these mixed areas will be determined
according to the size of the area served by that valve. Water use of
trees planted in that area will not be calculated separately. The
landscape coefficient for that valve will be calculated as usual
according to the species with the highest water use and the
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microclimate, assuming a density factor of 1.3. This density factor
is assumed to be the most likely; it is agreed that some
circumstances may require a different number.
The plant water requirement will be calculated on the basis of the
entire mixed-planting area, including the trees.
Trees in these areas of mixed plant types shall still be served by a
separate valve or circuit. The valve shall be itemized in the Water
Use Calculations along with all the other valves and identified as
serving trees, but no additional square footage or water use will be
added into the calculations.
,,
iii. For water use calculations purposes, trees classified by the
Water use Classification of Landscape Species list (WUCOLS) in
the very low category (requiring <10% ETo), need not be included
in water use calculations. It is assumed that these species may be
successfully irrigated by winter rainfall alone.
iv. For purposes of developing water budgets under these
Standards, the species Sequois sempervirens, Coast Redwood,
shall be classified as a medium water-use species. Medium water-
use species require irrigation of 40-60% of local ETo per year.
Irrigation Schedule
Two irrigation schedules shall be submitted, one for the initial
establishment period and one for the established landscape.
The irrigation schedules will include total run time and number of cycles
with run time per cycle for each station. The schedule will also provide the
amount of applied water (in CCF, hundred cubic feet) recommended on a
monthly and almual basis.
Irrigation Efficiency
Irrigation systems shall be designed, constructed, managed, and
maintained to achieve as high an overall efficiency as possible. Irrigation
efficiency (IE) is calculated as follows:
IF. = Design Efficiency (DE) x Management Efficiency (ME)
a.Design Efficiency
13
bo
DE is based on equipment performance and design factors.
2 in Appendix 3 lists efflciencies that are acceptable for the
purpose of conforming with these standards.
Table
Management Efficiency
ME is based on scheduling procedures and maintenance practices.
The manag&nent efficiency shall be assumed to be 80% with the
use of monthly irrigation schedules, inspection of turf areas after
mowing, bi-monthly non-turf irrigation system inspections,
controllers turned off during rainy periods, and appropriate system
maintenance. The management efficiency may be increased by
adding automated scheduling equipment and flow sensing control
systems as described below to the above requirements.
The City will not consider a lower management efficiency
percentage in the calculation of maximum water requirements. If
inspection and maintenance are neglected, the overall efficiency of
the system will decrease over time. The result is likely to be
increased costs, either in replacing plant materials or in excess
water use, or both.
Automated Scheduling Equipment
With the additional installation of automatic scheduling
equipment, management efficiency shall be assumed to be
increased by 5%. Automated scheduling equipment refers to
Central Computer Control utilizing an ETo weather station
(CIMIS) or any other acceptable locaiET weather station.
Flow Sensing Control System
With the installation of a flow sensing control system in addition
to the basic practices itemized in Section b. above, management
efficiency shall be assumed to be increased by 5% when the
following conditions are met:
i. The flow sensing control system shall include a flow sensor and
an integral irrigation controller that can monitor station GPM for
overflow, underflow and main line breaks.
ii. The controller shall be capable of shutting off 1)
malfunctioning individual stations without disrupting the
remaining program and 2) the master valve in the event of a
14
mainline or valve failure downstream.
Documents to be submitted for Irrigation Plan Review
a.Water Use Statement
bo
A landscape water use statement in the form which appears in
Appendix 1 shall be submitted with the plans for every project.
This landscape water use statement defines the maximum
landscape water allowance for each site. Therefore it should
be completed before final planting or irrigation designs are
developed.
Copies of this form are available from the City:
City of Palo Alto Development Center
285 Hamilton Avenue
Palo Alto, CA 94301
Tel: 650. 617.3118
Or, from Palo Alto Department of Utilities
Utilities Marketing. Services
250 Hamilton Avenue
Palo Alto, CA 94301
Tel: 650.329.2241
Irrigation Drawings and Details
Drawings shall be the same scale as the landscape planting plan
and shall accurately and clearly identify:
i. Location of the landscape water meter.
ii. Minimum static pressure at the point of connection. The
nominal system static pressure for each of the Palo Alto water
service areas is availablefrom the Palo Alto Water Transmission
Supervisor at:
Department of Utilities
Water-Gas-Wastewater/Municipal Services Center
3201 E. Bayshore Blvd.
Palo Alto, CA 94303 Tel: 650.617.6982
iii. Location, type, and size of all components of the irrigation
system, including electronic controllers, main and lateral lines,
valves, application devices, rain shutoff sensors, flow sensors, soil
moisture sensors, booster pumps and backflow prevention devices.
15
Do
iv. Station/Zone number, valve size, and flow rate (GPM).
v. Spot elevations from the grading plans should be indicated
when used in calculating operating pressures.
vi. Details of assembly and installation.
c.Specifications and Details
Specifications shall prescribe quality of materials, standards of
workmanship, expected results, and guarantees and include details
as required.
do Calculation Worksheets
A summary of the information used to determine landscape water
requirements and irrigation efficiency shall be submitted in a form
similar to the Water Use Calculations sheet in Appendix 3. The
City requires documentation of the values used to determine the
total estimated irrigation requirement. Documentation in other
formats which provide substantially the same information and
which are clearly itemized and concise may be submitted for
review. ..
Maintenance Specifications
1.Irrigation System Inspections
Note: The following paragraph will be included in the irrigation
system notes:
The irrigation system should be inspected after each mowing for turf areas
and hi-monthly in other areas for the life of the system. This >wet-cheek=
inspection consists of operating the valves and observing the performance
of each irrigation zone.
2.Irrigation System Maintenance
Note: The following paragraph will be included in the irrigation
system details:
The irrigation system should be kept clean and properly adjusted.
Damaged equipment should be repaired pr. omptly with identical
16 ’
equipment to maintain the original design integrity.
Irrigation shall be scheduled according to any emergency water use
ordinance in effect.
Whenever possible, irrigation management shall incorporate the use of
real-time ETo data from the California Irrigation Management Information
System (CIMIS), or other site-specific, electronically monitored, ETo
calculating system.
Certification
A Certificate of Substantial Completion, Appendix 5, shall be submitted within 30
days of completing the installation of landscaping. It is the responsibility of the
applicant for the Building or Grading Permit to arrange for the Certification to be
submitted.
VI.
The Certification shall be submitted to:Water-Gas-Wastewater Engineering
New Services Office
Palo Alto Department of Utilities
P.O. Box 10250
Palo Alto, CA 94303
Failure to submitthe Certificate of Substantial Completion within 30 days of
installation of the landscape will result in warning notices of installation of a flow
restrictor in the irrigation water meter. Should the Certificate of Substantial
Completion not be submitted within the time specified on the warning notice, the
flow restrictor will be installed and will remain until the Certificate of Substantial
Completion is submitted.
Alternative Equipment or Design
The City realizes that more and more research is being conducted on plant water needs, in
mixed plantings as well as for individual species. ’As this data becomes available and is
accepted by landscape professionals, more detailed data may be available than that
itemized in Table 1, Appendix 3. The City will accept alternative methodologies for
calculating, plant water needs as long. as the methodology has been endorsed and accepted
by appropriate academic and professional organizations.
Also, new and increasingly efficient irrigation equipment is being designed and
manufactured. Irrigation designers may submit test data to support different efflciencies
for irrigation application devices other than those listed in Table 2, Appendix’3..
Acceptable test data will include, at a minimum, results based on field testing, not bench
17
VII.
testing, endorsed and accepted by appropriate professionals.
Water Use Monitoring
Landscape water use will be monitored on an annual basis for comparison to the
MWA. All irrigation accounts which have been established as a result of an
approved landscape plan will be subject to annual review by the Department of
Utilities.
Water usewill be based on utility records of the water meter installed as
the irrigation meter for each landscape.
The first 18 months after planting will be consideredas the establishment
period for the landscape plant materials.
3.Irrigation water use will not be compared to the MWA for that landscape
until 12 months after the 18-month establishment period.
If the irrigation account water use is lower than or equal to the MWA, the
landscape shall be designated as a water-efficient landscape. The Water Efficient
Landscape status will remain in effect as long as the irrigation water use remains
lower than or equal to the MWA.
If the irrigation account water use is greater than the MWA, the landscape shall
have a landscape irrigation audit.
Landscape Water Manage~nent Program as described in the Landscape
Irrigation Auditor Handbook, the entire document that is hereby
incorporated by reference. See: Landscape Irrigation Auditor Handbook,
Department of Water Resources, Water Conservation Office, June 1990,
version 5.5, or latest version.
The audit report shall be delivered to the Department of Utilities within 90
days of notification of excess water use.
18
APPENDIX 1
,Applicant
Address of Project
Project Name
Total Landscaped Area
Maximum Water Allowance:
Landscape Water Use Statement
Date
(No of square feet)
Maximum water use for projects in Palo Alto is based on the formula below. Annual
historical Eto is 43.1 inches per year. The ET adjustment factoris 0.80. The number
.00083 converts inches per year into CCF.
43.1 x 0.80 x x .00083 --
(Eto)(Adj. Factor)(Area)(Conversion (Annual Total)
To CCF)
Landscape Water Requirements:
CCF
Enter the landscape water required, e.g., from a water use calculations form.
The estimated applied water use may not exceed the Maximum Water allowance.
Estimated Landscape Irrigation Water Required:
Estimated Non-irrigation Landscape Water Required:
Estimated Applied Water Use:
CCF
CCF
CCF
Certification:
I certify that this landscape plan has been developed according to the Landscape Water
Efficiency Ordinance of the City of Palo Alto and that this statement represents the
landscape water allowance and estimated water requirementd of this project.
Name of Landscape Architect or Irrigation Designer
Address
Signature
Telephone
Clef OF PALO A~I~O
UTILITIES
20
APPENDIX
Landscape
Applicant’
Address 0fProject
Water Use Statement
Date
Project Name
Total Landscaped Area .(No of square feet)
Maximum Water AIIowance:
Maximum water use for projects in Palo Alto is based on the formula below. Annual
historical Eto is 43.1 inches per year. The ET adjustment factor is 0.80. The number
.00083 converts inches per year into CCF.
43.1 x 0.80 x x .00083 =CCF
(Eto)(Adj. Factor)(Area)(Conversion (Annual Total)
To CCF)
Landscape Water Requirements:
Enter the landscape water required, e.g., from a water use calculations form.
The estimated applied water use may not exceed the Maximum Water allowance.
Estimated Landscape Irrigation Water Required:CCF
Estimated Non-irrigation Landscape Water Required:CCF
Estimated Applied Water Use:CCF
Certification:
I certify that this landscape plan has been developed according to the Landscape Water
Efficiency Ordinance of the City of Palo Alto and that this statement represents the
landscape water allowance and estimated water requirements of this project.
Name of Landscape Architect or Irrigation Designer Telephone
Address
Signature CITY OF PALO ALTO
UTILITIES
20
APPENDIX 2
SAMPLE STATEMENT OF DESIGN INTENT
Project:(fill in project name, e.g., "Shady Acres Homesites")
Address:(to be filled in)
Statement of Aesthetic and Functional Vision and Description of Landscape at Maturity
Shady Acres Homesites is a planned forty-five home development. At maturity the
landscape will consist largely-of northern California plants that grow naturally in an oak
woo. dland, combined with exotic materials, all of whicli have low maintenance and low
water-use characteristics. Materials will be a mix of deciduous and evergreen plantings.
The bulk of the colorful aspects of thelandscape will have to do with seasonal color and
use of variegated leaf forms in !ieu of high maintenance flower plantings.
2.Statement Related to Planting and Irrigation Systems
The plant materials have been chosen for water-conserving and reduced-maintenance
characteristics. Plantings will be done from container sizes that are commonly available
through nurseries and that are optimum for future plant growth.
The irrigation system for the projec.t will be automated through the use of a series of
electronic irrigation controllers. Irrigation valve circuits will be primarily for drip
irrigation, exqept for those areas where turf is used. In small turf areas, low precipitation
spray hefids will be used, and in large turf areas, such as the parks, low precipitation rate
rotor heads will be used.
Proj ected Long-Range Maintenance of the Project until Maturity.
The landscaped areas are designed to have a ’natural’ appearance at maturity. Because
materials were selected for their water conserving and minimal maintenance qualities, the
primary goal of maintenance at maturity will be to keep large turf areas in parks, and
small turf areas near residences, well maintained.
As materials have been mixed to create a ’poly-cultural’ landscape and because materials
resistant to oak root fungus (Armillaria spp.) will be used, it is anticipated that there will
be no need for additional spraying for insects or diseases, at maturity. A pre-emergent
herbicide will be specified in ground cover and shrub planting areas initially, and mulches
will be used in all bare areas for the life of the project until such time as ground covers
and shrubs have naturally formed canopies over the ground.
21
APPENDIX 3
WATER USE CALCULATIONS
City Requirements
The City requires documentation of the values used in determining the total estimated
landscape irrigation requirement for a project. The Water Use Calculations form provides
a convenient format for summarizing diverse information and deriving those values.
Landscape architects or irrigation designers may wish to use another format or software
application with which they are already familiar.
The total amount of water for the project shall include water designated as the Estimated
landscape Irrigation Water Required as well as the Estimated Non-Irrigation Water
Required.
Options
The landscape architect or irrigation designer may choose whether or not to include
effective precipitation in completing the calculations. Up to 25% of local annual mean
precipitation may be used.
-The 30-year mean in Palo Alto from 1961 - 1990 is 15.07 inches.
The 25% of local mean annual precipitation is used in completing the plant water
requirement formula in column (f) of the Water Use Calculations form. The column
offers two options. Option 1 uses reference evapotranspiration, item (a). Option 2 uses the
calculation for effective precipitation to derive a Net ETo value, item (S), for use in the
formula.
Only oneoption may be selected for .purposes of completing the form. Whichever option
is selected must be used throughout the calculations.
Water Features
Water use for water features is calculated as 100% of Eto per square foot of surface area.
This amount is included in non-irrigation landscape water required and entered in the
’Landscape Water Use Statement.’
22
.((,
zZLU
(u~ld ope~F~!
( (~ =ooo) x
( (~ =oo0’) x
~) x (p] (s) :=~
.~0
mid :1 )pdo)
z
ou- ~:~
(m Eupue l um.Jj ~J~ renp
(UelC ~upuqd LUO.~j)
r,o~(Ueld m!:le~!,~.~! ~uoJj)
WATER USE CALCULATIONS, continued:Page 2 of 2
Irrigation System management Practices:
EFFICIENCY DESCRIPTION
80%Minimum requirements - Irrigation Base Schedules, Routine
Irrigation system Inspections, appropriate System Maintenance
as described in Section V.C.3.b.
5%
5%
The use of automated scheduling equipment as described in
Section V.C.3.c. in addition to minimum requirements, above.
The use of a flow sensing control system installed as indicated in
Section V.C.3.d. in addition to minimum requirements, above.
Average Management Efficiency: (n)
(Select from Efficiency Column and enter that percentage here.)
Estimated Irrigation Water Requirement:
Irrigation Efficiency: (o)
(Average Design Eficiency, (m), t.imes Average Management Eficiency, (n)
Total Estimated Irrigation Requirement: CCF (p)
(Total Plant Water Requirement, (k), divided bylrrigation Efficiency, (o).)
Enter the total Estimated Irrigation Requirement from this page on the Landscape Water use State-
ment. The Total Estimated Irrigation Requirement may not exceed the Maximum Water Allowance.
CiTY OF PALO ALTO
UTILITIES
24
Table 1: Landscape Coefficients
This table itemizes a landscape coefficient methodology which is acceptable for the purpose of
conforming to these standards.* The method is based on the formula:
Kr. = Ks x Kd x Kmc
Where: KL = landscape coefficient
Ks = species factor
Kd = density factor
Kmc = microclimate factor
The KL derived from this formula may be inserted in column (d) of the Water use Calculations sheet.
The Plant Water Requirement may then be calculated as itemized in column (f) of the sheet.
Table 1 : Estimated values for species, density,, and microclimate factors used to determine the landscape
coefficient (KL) for selected vegetation types.
Density factor
Vegetation Type
high
2Trees
Shrubs
Groundcovers
Mixed:3
trees, shrubs,
groundcovers
Species factor
(Ks)
high .avg low
0.9 0.5 0.2
0.7 0.5 0.2
0.7 0.5 0.2
0.9 0.5 0.2
0.8 0.7 na
(Kd)
high avg low
1.3 1.0
1.1 1.0
1.1 1.0
1.3 1.1
110 1.0
0.5 1.4
0.5 1.3
0.5. "’1.2
.06 1.4
0.6 1.2
Microclimate factor
(Kmc)
avg low
1.0 0.5
1.0 0.5
1.0 0.5
1.0 0.5
1.0 0.84Turfgrass
1Species factor values are based on the Water Use Classification of Landscape Species list. This list is
available from the state Department of Water Resources or from Utility Marketing Services of the Palo Alto
Department of Utilities.
2The tree, shrub, and groundcover categories listed are for landscapes that are composed solely or
predominately of one of these vegetation types.
3Mixed plantings are composed of two or all three vegetation types (i.e., where a single vegetation type does
not predominate).
4A low Ks value (0.6)¯should be assigned to warm-season tuff, and a high value (0.8).to cool-season turf.
NOTE: It is assumed that there is no bare soil surface within the landscape plant.ing. Otherwise, Kd should be " ’
increased 10 to 20%, especially for trees and shrubs, due to soil surface evaporation.
Reprinted with permission from: Estimating Water Requirements of Landscape Plantings. Costello, Matheny, and
Clark. Cooperative Extension University of California, Division of Agriculture and Natural Resources. Leaflet
21493.
*See Note, p.26
25
Table 2: Design Efficiency
This table lists design efficiencies which are acceptable for the purpose of conforming to these ¯
standards.*
The efficiency percentage of the application devices for a station or zone may be inserted in
column (h) of the Water Use Calculations sheet. That number is then used in the calculation
indicated in column (i) of the sheet to obtain the Zone Water Requirement.
The following table assumes Infiltration uniformity equals distribution uniformity.
Optimum and consistent operating pressure.
Irrigation zone pressure differential maximum 10%.
Table 2:. AVERAGE DESIGN EFFICIENCIES OF VARIOUS APPLICATION DEVICES
NOTES1 APPLICATION DEVICE
A
A
A
A&B
B
B
C
D
F
Multiple Stream & Impact Rotors
Single Stream-Rotors
Spray Heads in turf
Spray Heads in ground covers and shrubs
Micro Spray - 6 Ft. Radius or less
Micro Spray - 6 Ft. Radius or more
Bubblers
Drip Emitters
Multi-port Emitters
RANGE
PERCENT
60 - 80
60 - 80
40 - 60
60 - 80
60 - 80
40 - 60
60 - 90
50 - 90
50 - 90
AVERAGE
PERCENT
70
70
5O
5O
70
5O
85
80
8O
1Footnotes:
(A)
(B)
(c)(D)
(F)
Symmetrical patterns, head-to-head spacing, matched precipitation, winds less than 5
mph.
No plant deflection, wind less than 5 mph.
Bubblers place.d in Watering basins to prevent runoff.
Efficiency drops with age (i.e., clogging, no provisions for expanding root zones).
Efficiency is highly variable.
*Note~ Alternative data may be submitted for that in either Table .1 or Table 2. Refer to
Section VI, p’. 18,
26
APPENDIX 4
REQUIREMENTS FOR LANDSCAPES WITH TREATED GROUNDWATER IRRIGATION
SYSTEMS
The following requirements must be met for landscapes where treated groundwater.will be the
source of irrigation water:
A brief description of the groundwater treatment system including a letter from the
project engineer or other person authorized by the owner stating the size and components
of the system, when the system will be in operation, the maximum gpd produced by the
system, and a full layout plan of the system.
A copy of a laboratory test of the treated groundwater for horticultural suitability.
A letter from the owner or authorized representative stating whether owner has a
permit from the City to discharge excess treated groundwater into the sanitary sewer, and
if applicable, a permit from the Regional Water Quality Control Board to discharge
excess treated ground water into a storm drain or creek.
A statement from the owner or authorized representative describing the provisions for
irrigation should thegroundwater treatment system malfunction causing irrigation water
to be unavailable.
The irrigation system shall be separated from" the City of Palo Alto water supply by a
backflow prevention device or devices approved by the City Utilities Department Cross
Connection Control Officer.
Full set of a) grading, b) planting, and c) irrigation plans with details and specifications,
as specified in the Landscape Water Efficiency Standards.
The total amount of landscaped area in square feet.
27
APPENDIX 5
Project Name:
Project Address:
Building Permit No.
I/We hereby certify the following:
1.
CITY OF PALO ALTO
DEPARTMENT OF UTILITIES
Certificate of Substantial Completion
The landscaping work for the above project has been completed insubstantial conformance to
the City-approved planting and irrigation plans and specifications;
The automatic controller-has been set according to the approved irrigation schedule for the plant
establishment period;
The irrigation system has been adjusted to maximize irrigation efficiency and minimize overspray
and runoff; and
A copy of the irrigation schedules have been given to the property owner’or his/her
representative.
Certificate prepared by:
Signature, Landscape Architect or Owner’s Representative Date
Please print name.State License Number
Signature,.Installing Landscape Contractor ¯Date
Please print name.State License Number
Submitloriginal Certification to:Water-Gas-Wastewater Engineering
New Services.Office
Palo Alto Department of Utilities
P.O. Box 10250
Palo Alto, CA 94303
Certification to be submitted within 3 0 days of landscape installation to ensure continuation of water
service.
28
RESOLUTION NO.
RESOLUTION OF THE COUNCIL OF THE CITY OF PALO
ALTO ADOPTING REVISED LANDSCAPE WATER EFFICIENCY
STANDARDS PURSUANT TO PALO ALTO MUNICIPAL CODE
SECTION 12.32.040 (WATER EFFICIENT LANDSCAPE
ORDINANCE)OF CHAPTER 12.32 (WATER USE
REGULATIONS)
WHEREAS, pursuant to section 12.32.040 of the Palo Alto
Municipal Code, the City Council may. by resolution adopt
standards for landscape water efficiency, and the City has
adopted the .Landscape Water Efficiency Standards of the City of
Palo Alto, as.they may be.amended from time to time; and
WHEREAS, the City wishes to require the filing of a
certificate of. substantial completion within thirty days of
completion of the installation of landscaping; and
WHEREAS,
Landscape Water
California law.
the City has determined
Efficiency Standards are
that the revised
consistent with
NOW THEREFORE, the Council does hereby RESOLVE as
follows:
SECTION i. The Council hereby finds that it is in the
interests of public health, safety and welfare and consistent
with State of California and local laws promoting conservation
and the efficient use of water to adopt a certification
requirement for the completion of landscaping installation work.
The Council hereby adopts the revised Landscape Water Efficiency
Standards for the City of Palo Alto, attached hereto and
incorporated herein by this reference as Exhibit A.
SECTION 2. The City Council has determined that the
adoption of this Resolution is categorically exempt from. the
California Environmental Quality Act pursuant to Section 15307
of Title 14 of the California Code of Regulations, because this
constitutes an action authorized by California law to ensure the
//
I/
//
020729 syn 0072189
maintenance, restoration, or enhancement of a natugal resource
where the regulatory process involves procedures for the
protection of the environment.
INTRODUCED AND PASSED:
AYES:
NOES:
ABSENT:.
ABSTENTIONS:
ATTEST:APPROVED:
City Clerk
APPROVED AS TO FORM:
Mayor
City Manager
Senior Asst. City Attorney
Director of Utilitie~
Director of Administrative
Services
020729 syn 0072189
2