HomeMy WebLinkAbout103-California Department of Water Resources Model Water Efficient Landscape Ordinance .pdf
Model Water Efficient Landscape Ordinance
September 10, 2009
Index
Page
490. Purpose 1
490.1 Applicability 1
491. Definitions 2
492. Provisions for New Construction or Rehabilitated Landscapes 6
492.1 Compliance with Landscape Documentation Package 6
492.2 Penalties 6
492.3 Elements of the Landscape Documentation Package 7
492.4 Water Efficient Landscape Worksheet 7
492.5 Soil Management Report 10
492.6 Landscape Design Plan 10
492.7 Irrigation Design Plan 12
492.8 Grading Design Plan 14
492.9 Certificate of Completion 15
492.10 Irrigation Scheduling 15
492.11 Landscape and Irrigation Maintenance Schedule 16
492.12 Irrigation Audit, Irrigation Survey, and Irrigation Water Use Analysis 16
492.13 Irrigation Efficiency 17
492.14 Recycled Water 17
492.15 Stormwater Management 17
492.16 Public Education 17
492.17 Environmental Review 18
493. Provisions for Existing Landscapes 18
493.1 Irrigation Audit, Irrigation Survey, and Irrigation Water Use Analysis 18
493.2 Water Waste Prevention 18
494. Effective Precipitation 18
Appendices 19
Appendix A. Reference Evapotranspiration (ETo) Table 19
Appendix B. Sample Water Efficient Landscape Worksheet 28
Section B1. Maximum Applied Water Allowance (MAWA) 29
Section B2. Estimated Total Water Use (ETWU) 30
Appendix C. Sample Certificate of Completion 31
1
California Code of Regulations
Title 23. Waters
Division 2. Department of Water Resources
Chapter 2.7. Model Water Efficient Landscape Ordinance
§ 490. Purpose.
(a) The State Legislature has found:
(1) that the waters of the state are of limited supply and are subject to ever increasing demands;
(2) that the continuation of California’s economic prosperity is dependent on the availability of adequate
supplies of water for future uses;
(3) that it is the policy of the State to promote the conservation and efficient use of water and to prevent
the waste of this valuable resource;
(4) that landscapes are essential to the quality of life in California by providing areas for active and
passive recreation and as an enhancement to the environment by cleaning air and water, preventing
erosion, offering fire protection, and replacing ecosystems lost to development; and
(5) that landscape design, installation, maintenance and management can and should be water efficient;
and
(6) that Section 2 of Article X of the California Constitution specifies that the right to use water is
limited to the amount reasonably required for the beneficial use to be served and the right does not and
shall not extend to waste or unreasonable method of use.
(b) Consistent with these legislative findings, the purpose of this model ordinance is to:
(1) promote the values and benefits of landscapes while recognizing the need to invest water and other
resources as efficiently as possible;
(2) establish a structure for planning, designing, installing, maintaining and managing water efficient
landscapes in new construction and rehabilitated projects;
(3) establish provisions for water management practices and water waste prevention for existing
landscapes;
(4) use water efficiently without waste by setting a Maximum Applied Water Allowance as an upper
limit for water use and reduce water use to the lowest practical amount;
(5) promote the benefits of consistent landscape ordinances with neighboring local and regional
agencies;
(6) encourage local agencies and water purveyors to use economic incentives that promote the efficient
use of water, such as implementing a tiered-rate structure; and
(7) encourage local agencies to designate the necessary authority that implements and enforces the
provisions of the Model Water Efficient Landscape Ordinance or its local landscape ordinance.
Note: Authority cited: Section 65593, Government Code. Reference: Sections 65591, 65593, 65596,
Government Code.
§ 490.1 Applicability
(a) After January 1, 2010, this ordinance shall apply to all of the following landscape projects:
(1) new construction and rehabilitated landscapes for public agency projects and private development
projects with a landscape area equal to or greater than 2,500 square feet requiring a building or
landscape permit, plan check or design review;
(2) new construction and rehabilitated landscapes which are developer-installed in single-family and
multi-family projects with a landscape area equal to or greater than 2,500 square feet requiring a
building or landscape permit, plan check, or design review;
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(3) new construction landscapes which are homeowner-provided and/or homeowner-hired in single-
family and multi-family residential projects with a total project landscape area equal to or greater than
5,000 square feet requiring a building or landscape permit, plan check or design review;
(4) existing landscapes limited to Sections 493, 493.1 and 493.2; and
(5) cemeteries. Recognizing the special landscape management needs of cemeteries, new and
rehabilitated cemeteries are limited to Sections 492.4, 492.11 and 492.12; and existing cemeteries are
limited to Sections 493, 493.1 and 493.2.
(b) This ordinance does not apply to:
(1) registered local, state or federal historical sites;
(2) ecological restoration projects that do not require a permanent irrigation system;
(3) mined-land reclamation projects that do not require a permanent irrigation system; or
(4) plant collections, as part of botanical gardens and arboretums open to the public.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
§ 491. Definitions.
The terms used in this ordinance have the meaning set forth below:
(a) “applied water” means the portion of water supplied by the irrigation system to the landscape.
(b) “automatic irrigation controller” means an automatic timing device used to remotely control valves
that operate an irrigation system. Automatic irrigation controllers schedule irrigation events using either
evapotranspiration (weather-based) or soil moisture data.
(c) “backflow prevention device” means a safety device used to prevent pollution or contamination of
the water supply due to the reverse flow of water from the irrigation system.
(d) “Certificate of Completion” means the document required under Section 492.9.
(e) “certified irrigation designer” means a person certified to design irrigation systems by an accredited
academic institution a professional trade organization or other program such as the US Environmental
Protection Agency’s WaterSense irrigation designer certification program and Irrigation Association’s
Certified Irrigation Designer program.
(f) “certified landscape irrigation auditor” means a person certified to perform landscape irrigation
audits by an accredited academic institution, a professional trade organization or other program such as
the US Environmental Protection Agency’s WaterSense irrigation auditor certification program and
Irrigation Association’s Certified Landscape Irrigation Auditor program.
(g) “check valve” or “anti-drain valve” means a valve located under a sprinkler head, or other location in
the irrigation system, to hold water in the system to prevent drainage from sprinkler heads when the
sprinkler is off.
(h) “common interest developments” means community apartment projects, condominium projects,
planned developments, and stock cooperatives per Civil Code Section 1351.
(i) “conversion factor (0.62)” means the number that converts acre-inches per acre per year to gallons
per square foot per year
(j) “drip irrigation” means any non-spray low volume irrigation system utilizing emission devices with a
flow rate measured in gallons per hour. Low volume irrigation systems are specifically designed to
apply small volumes of water slowly at or near the root zone of plants.
(k) “ecological restoration project” means a project where the site is intentionally altered to establish a
defined, indigenous, historic ecosystem.
(l)“effective precipitation” or “usable rainfall” (Eppt) means the portion of total precipitation which
becomes available for plant growth.
(m) “emitter” means a drip irrigation emission device that delivers water slowly from the system to the
soil.
(n) “established landscape” means the point at which plants in the landscape have developed significant
root growth into the soil. Typically, most plants are established after one or two years of growth.
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(o) “establishment period of the plants” means the first year after installing the plant in the landscape or
the first two years if irrigation will be terminated after establishment. Typically, most plants are
established after one or two years of growth.
(p) “Estimated Total Water Use” (ETWU) means the total water used for the landscape as described in
Section 492.4.
(q) “ET adjustment factor” (ETAF) means a factor of 0.7, that, when applied to reference
evapotranspiration, adjusts for plant factors and irrigation efficiency, two major influences upon the
amount of water that needs to be applied to the landscape.
A combined plant mix with a site-wide average of 0.5 is the basis of the plant factor portion of this
calculation. For purposes of the ETAF, the average irrigation efficiency is 0.71. Therefore, the ET
Adjustment Factor is (0.7)=(0.5/0.71). ETAF for a Special Landscape Area shall not exceed 1.0. ETAF
for existing non-rehabilitated landscapes is 0.8.
(r) “evapotranspiration rate” means the quantity of water evaporated from adjacent soil and other
surfaces and transpired by plants during a specified time.
(s) “flow rate” means the rate at which water flows through pipes, valves and emission devices,
measured in gallons per minute, gallons per hour, or cubic feet per second.
(t) “hardscapes” means any durable material (pervious and non-pervious).
(u) “homeowner-provided landscaping” means any landscaping either installed by a private individual
for a single family residence or installed by a licensed contractor hired by a homeowner. A homeowner,
for purposes of this ordinance, is a person who occupies the dwelling he or she owns. This excludes
speculative homes, which are not owner-occupied dwellings.
(v) “hydrozone” means a portion of the landscaped area having plants with similar water needs. A
hydrozone may be irrigated or non-irrigated.
(w) “infiltration rate” means the rate of water entry into the soil expressed as a depth of water per unit of
time (e.g., inches per hour).
(x)“invasive plant species” means species of plants not historically found in California that spread
outside cultivated areas and can damage environmental or economic resources. Invasive species may be
regulated by county agricultural agencies as noxious species. “Noxious weeds” means any weed
designated by the Weed Control Regulations in the Weed Control Act and identified on a Regional
District noxious weed control list. Lists of invasive plants are maintained at the California Invasive Plant
Inventory and USDA invasive and noxious weeds database.
(y) “irrigation audit” means an in-depth evaluation of the performance of an irrigation system conducted
by a Certified Landscape Irrigation Auditor. An irrigation audit includes, but is not limited to: inspection,
system tune-up, system test with distribution uniformity or emission uniformity, reporting overspray or
runoff that causes overland flow, and preparation of an irrigation schedule.
(z) “irrigation efficiency” (IE) means the measurement of the amount of water beneficially used divided
by the amount of water applied. Irrigation efficiency is derived from measurements and estimates of
irrigation system characteristics and management practices. The minimum average irrigation efficiency
for purposes of this ordinance is 0.71. Greater irrigation efficiency can be expected from well designed
and maintained systems.
(aa) “irrigation survey” means an evaluation of an irrigation system that is less detailed than an irrigation
audit. An irrigation survey includes, but is not limited to: inspection, system test, and written
recommendations to improve performance of the irrigation system.
(bb) “irrigation water use analysis” means an analysis of water use data based on meter readings and
billing data.
(cc) “landscape architect” means a person who holds a license to practice landscape architecture in the
state of California Business and Professions Code, Section 5615.
(dd) “landscape area” means all the planting areas, turf areas, and water features in a landscape design
plan subject to the Maximum Applied Water Allowance calculation. The landscape area does not
include footprints of buildings or structures, sidewalks, driveways, parking lots, decks, patios, gravel or
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stone walks, other pervious or non-pervious hardscapes, and other non-irrigated areas designated for
non-development (e.g., open spaces and existing native vegetation).
(ee) “landscape contractor” means a person licensed by the state of California to construct, maintain,
repair, install, or subcontract the development of landscape systems.
(ff) “Landscape Documentation Package” means the documents required under Section 492.3.
(gg) “landscape project” means total area of landscape in a project as defined in “landscape area” for the
purposes of this ordinance, meeting requirements under Section 490.1.
(hh) “lateral line” means the water delivery pipeline that supplies water to the emitters or sprinklers from
the valve.
(ii) “local agency” means a city or county, including a charter city or charter county, that is responsible
for adopting and implementing the ordinance. The local agency is also responsible for the enforcement
of this ordinance, including but not limited to, approval of a permit and plan check or design review of a
project.
(jj) “local water purveyor” means any entity, including a public agency, city, county, or private water
company that provides retail water service.
(kk) “low volume irrigation” means the application of irrigation water at low pressure through a system
of tubing or lateral lines and low-volume emitters such as drip, drip lines, and bubblers. Low volume
irrigation systems are specifically designed to apply small volumes of water slowly at or near the root
zone of plants.
(ll) “main line” means the pressurized pipeline that delivers water from the water source to the valve or
outlet.
(mm) “Maximum Applied Water Allowance” (MAWA) means the upper limit of annual applied water
for the established landscaped area as specified in Section 492.4. It is based upon the area’s reference
evapotranspiration, the ET Adjustment Factor, and the size of the landscape area. The Estimated Total
Water Use shall not exceed the Maximum Applied Water Allowance. Special Landscape Areas,
including recreation areas, areas permanently and solely dedicated to edible plants such as orchards and
vegetable gardens, and areas irrigated with recycled water are subject to the MAWA with an ETAF not
to exceed 1.0.
(nn) “microclimate” means the climate of a small, specific area that may contrast with the climate of the
overall landscape area due to factors such as wind, sun exposure, plant density, or proximity to reflective
surfaces.
(oo) “mined-land reclamation projects” means any surface mining operation with a reclamation plan
approved in accordance with the Surface Mining and Reclamation Act of 1975.
(pp) “mulch” means any organic material such as leaves, bark, straw, compost, or inorganic mineral
materials such as rocks, gravel, and decomposed granite left loose and applied to the soil surface for the
beneficial purposes of reducing evaporation, suppressing weeds, moderating soil temperature, and
preventing soil erosion.
(qq) “new construction” means, for the purposes of this ordinance, a new building with a landscape or
other new landscape, such as a park, playground, or greenbelt without an associated building.
(rr) “operating pressure” means the pressure at which the parts of an irrigation system are designed by
the manufacturer to operate.
(ss) “overhead sprinkler irrigation systems” means systems that deliver water through the air (e.g., spray
heads and rotors).
(tt) “overspray” means the irrigation water which is delivered beyond the target area.
(uu) “permit” means an authorizing document issued by local agencies for new construction or
rehabilitated landscapes.
(vv) “pervious” means any surface or material that allows the passage of water through the material and
into the underlying soil.
(ww) “plant factor” or “plant water use factor” is a factor , when multiplied by ETo, estimates the
amount of water needed by plants. For purposes of this ordinance, the plant factor range for low water
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use plants is 0 to 0.3, the plant factor range for moderate water use plants is 0.4 to 0.6, and the plant
factor range for high water use plants is 0.7 to 1.0. Plant factors cited in this ordinance are derived from
the Department of Water Resources 2000 publication “Water Use Classification of Landscape Species”.
(xx) “precipitation rate” means the rate of application of water measured in inches per hour.
(yy) “project applicant” means the individual or entity submitting a Landscape Documentation Package
required under Section 492.3, to request a permit, plan check, or design review from the local agency. A
project applicant may be the property owner or his or her designee.
(zz) “rain sensor” or “rain sensing shutoff device” means a component which automatically suspends an
irrigation event when it rains.
(aaa) “record drawing” or “as-builts” means a set of reproducible drawings which show significant
changes in the work made during construction and which are usually based on drawings marked up in
the field and other data furnished by the contractor.
(bbb) “recreational area” means areas dedicated to active play such as parks, sports fields, and golf
courses where turf provides a playing surface.
(ccc) “recycled water”, “reclaimed water”, or “treated sewage effluent water” means treated or recycled
waste water of a quality suitable for non-potable uses such as landscape irrigation and water features.
This water is not intended for human consumption.
(ddd) “reference evapotranspiration” or “ETo” means a standard measurement of environmental
parameters which affect the water use of plants. ETo is expressed in inches per day, month, or year as
represented in Section 495.1, and is an estimate of the evapotranspiration of a large field of four- to
seven-inch tall, cool-season grass that is well watered. Reference evapotranspiration is used as the basis
of determining the Maximum Applied Water Allowance so that regional differences in climate can be
accommodated.
(eee) “rehabilitated landscape” means any re-landscaping project that requires a permit , plan check, or
design review, meets the requirements of Section 490.1, and the modified landscape area is equal to or
greater than 2,500 square feet, is 50% of the total landscape area, and the modifications are completed
within one year.
(fff) “runoff” means water which is not absorbed by the soil or landscape to which it is applied and
flows from the landscape area. For example, runoff may result from water that is applied at too great a
rate (application rate exceeds infiltration rate) or when there is a slope.
(ggg) “soil moisture sensing device” or “soil moisture sensor” means a device that measures the amount
of water in the soil. The device may also suspend or initiate an irrigation event.
(hhh) “soil texture” means the classification of soil based on its percentage of sand, silt, and clay.
(iii)“Special Landscape Area” (SLA) means an area of the landscape dedicated solely to edible plants,
areas irrigated with recycled water, water features using recycled water and areas dedicated to active
play such as parks, sports fields, golf courses, and where turf provides a playing surface.
(jjj) “sprinkler head” means a device which delivers water through a nozzle.
(kkk) “static water pressure” means the pipeline or municipal water supply pressure when water is not
flowing.
(lll) “station” means an area served by one valve or by a set of valves that operate simultaneously.
(mmm) “swing joint” means an irrigation component that provides a flexible, leak-free connection
between the emission device and lateral pipeline to allow movement in any direction and to prevent
equipment damage.
(nnn) “turf” means a ground cover surface of mowed grass. Annual bluegrass, Kentucky bluegrass,
Perennial ryegrass, Red fescue, and Tall fescue are cool-season grasses. Bermudagrass, Kikuyugrass,
Seashore Paspalum, St. Augustinegrass, Zoysiagrass, and Buffalo grass are warm-season grasses.
(ooo) “valve” means a device used to control the flow of water in the irrigation system.
(ppp) “water conserving plant species” means a plant species identified as having a low plant factor.
(qqq) “water feature” means a design element where open water performs an aesthetic or recreational
function. Water features include ponds, lakes, waterfalls, fountains, artificial streams, spas, and
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swimming pools (where water is artificially supplied). The surface area of water features is included in
the high water use hydrozone of the landscape area. Constructed wetlands used for on-site wastewater
treatment or stormwater best management practices that are not irrigated and used solely for water
treatment or stormwater retention are not water features and, therefore, are not subject to the water
budget calculation.
(rrr) “watering window” means the time of day irrigation is allowed.
(sss) “WUCOLS” means the Water Use Classification of Landscape Species published by the University
of California Cooperative Extension, the Department of Water Resources and the Bureau of
Reclamation, 2000.
Note: Authority Cited: Section 65595, Government Code. Reference: Sections 65592, 65596,
Government Code.
§ 492. Provisions for New Construction or Rehabilitated Landscapes.
(a) A local agency may designate another agency, such as a water purveyor, to implement some or all of
the requirements contained in this ordinance. Local agencies may collaborate with water purveyors to
define each entity’s specific responsibilities relating to this ordinance.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
§ 492.1 Compliance with Landscape Documentation Package.
(a) Prior to construction, the local agency shall:
(1) provide the project applicant with the ordinance and procedures for permits, plan checks, or design
reviews;
(2) review the Landscape Documentation Package submitted by the project applicant;
(3) approve or deny the Landscape Documentation Package;
(4) issue a permit or approve the plan check or design review for the project applicant; and
(5) upon approval of the Landscape Documentation Package, submit a copy of the Water Efficient
Landscape Worksheet to the local water purveyor.
(b) Prior to construction, the project applicant shall:
(1) submit a Landscape Documentation Package to the local agency.
(c) Upon approval of the Landscape Documentation Package by the local agency, the project applicant
shall:
(1) receive a permit or approval of the plan check or design review and record the date of the permit in
the Certificate of Completion;
(2) submit a copy of the approved Landscape Documentation Package along with the record drawings,
and any other information to the property owner or his/her designee; and
(3) submit a copy of the Water Efficient Landscape Worksheet to the local water purveyor.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
§ 492.2 Penalties.
(a) A local agency may establish and administer penalties to the project applicant for non-compliance
with the ordinance to the extent permitted by law.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
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§ 492.3 Elements of the Landscape Documentation Package.
(a) The Landscape Documentation Package shall include the following six (6) elements:
(1) project information;
(A) date
(B) project applicant
(C) project address (if available, parcel and/or lot number(s))
(D) total landscape area (square feet)
(E) project type (e.g., new, rehabilitated, public, private, cemetery, homeowner-installed)
(F) water supply type (e.g., potable, recycled, well) and identify the local retail water purveyor if the
applicant is not served by a private well
(G) checklist of all documents in Landscape Documentation Package
(H) project contacts to include contact information for the project applicant and property owner
(I) applicant signature and date with statement, “I agree to comply with the requirements of the water
efficient landscape ordinance and submit a complete Landscape Documentation Package”.
(2) Water Efficient Landscape Worksheet;
(A) hydrozone information table
(B) water budget calculations
1. Maximum Applied Water Allowance (MAWA)
2. Estimated Total Water Use (ETWU)
(3) soil management report;
(4) landscape design plan;
(5) irrigation design plan; and
(6) grading design plan.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
§ 492.4 Water Efficient Landscape Worksheet.
(a) A project applicant shall complete the Water Efficient Landscape Worksheet which contains two
sections (see sample worksheet in Appendix B):
(1) a hydrozone information table (see Appendix B, Section A) for the landscape project; and
(2) a water budget calculation (see Appendix B, Section B) for the landscape project. For the calculation
of the Maximum Applied Water Allowance and Estimated Total Water Use, a project applicant shall use
the ETo values from the Reference Evapotranspiration Table in Appendix A. For geographic areas not
covered in Appendix A, use data from other cities located nearby in the same reference
evapotranspiration zone, as found in the CIMIS Reference Evapotranspiration Zones Map, Department
of Water Resources, 1999.
(b) Water budget calculations shall adhere to the following requirements:
(1) The plant factor used shall be from WUCOLS. The plant factor ranges from 0 to 0.3 for low water
use plants, from 0.4 to 0.6 for moderate water use plants, and from 0.7 to 1.0 for high water use plants.
(2) All water features shall be included in the high water use hydrozone and temporarily irrigated areas
shall be included in the low water use hydrozone.
(3) All Special Landscape Areas shall be identified and their water use calculated as described below.
(4) ETAF for Special Landscape Areas shall not exceed 1.0.
(c) Maximum Applied Water Allowance
The Maximum Applied Water Allowance shall be calculated using the equation:
MAWA = (ETo) (0.62) [(0.7 x LA) + (0.3 x SLA)]
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The example calculations below are hypothetical to demonstrate proper use of the equations and do not
represent an existing and/or planned landscape project. The ETo values used in these calculations are
from the Reference Evapotranspiration Table in Appendix A, for planning purposes only. For actual
irrigation scheduling, automatic irrigation controllers are required and shall use current reference
evapotranspiration data, such as from the California Irrigation Management Information System
(CIMIS), other equivalent data, or soil moisture sensor data.
(1) Example MAWA calculation: a hypothetical landscape project in Fresno, CA with an irrigated
landscape area of 50,000 square feet without any Special Landscape Area (SLA= 0, no edible plants,
recreational areas, or use of recycled water). To calculate MAWA, the annual reference
evapotranspiration value for Fresno is 51.1 inches as listed in the Reference Evapotranspiration Table in
Appendix A.
MAWA = (ETo) (0.62) [(0.7 x LA) + (0.3 x SLA)]
MAWA = Maximum Applied Water Allowance (gallons per year)
ETo = Reference Evapotranspiration (inches per year)
0.62 = Conversion Factor (to gallons)
0.7 = ET Adjustment Factor (ETAF)
LA = Landscape Area including SLA (square feet)
0.3 = Additional Water Allowance for SLA
SLA = Special Landscape Area (square feet)
MAWA = (51.1 inches) (0.62) [(0.7 x 50,000 square feet) + (0.3 x 0)]
= 1,108,870 gallons per year
To convert from gallons per year to hundred-cubic-feet per year:
= 1,108,870/748 = 1,482 hundred-cubic-feet per year
(100 cubic feet = 748 gallons)
(2) In this next hypothetical example, the landscape project in Fresno, CA has the same ETo value of
51.1 inches and a total landscape area of 50,000 square feet. Within the 50,000 square foot project, there
is now a 2,000 square foot area planted with edible plants. This 2,000 square foot area is considered to
be a Special Landscape Area.
MAWA = (ETo) (0.62) [(0.7 x LA) + (0.3 x SLA)]
MAWA = (51.1 inches) (0.62) [(0.7 x 50,000 square feet) + (0.3 x 2,000 square feet)]
= 31.68 x [35,000 + 600] gallons per year
= 31.68 x 35,600 gallons per year
=1,127,808 gallons per year or 1,508 hundred-cubic-feet per year
(d) Estimated Total Water Use.
The Estimated Total Water Use shall be calculated using the equation below. The sum of the Estimated
Total Water Use calculated for all hydrozones shall not exceed MAWA.
Where:
ETWU = Estimated Total Water Use per year (gallons)
ETo = Reference Evapotranspiration (inches)
PF = Plant Factor from WUCOLS (see Section 491)
HA = Hydrozone Area [high, medium, and low water use areas] (square feet)
SLA = Special Landscape Area (square feet)
0.62 = Conversion Factor
IE = Irrigation Efficiency (minimum 0.71)
⎟⎠
⎞⎜⎝
⎛+=SLAIE
HAxPFEToETWU)62.0)((
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(1) Example ETWU calculation: landscape area is 50,000 square feet; plant water use type, plant factor,
and hydrozone area are shown in the table below. The ETo value is 51.1 inches per year. There are no
Special Landscape Areas (recreational area, area permanently and solely dedicated to edible plants, and
area irrigated with recycled water) in this example.
*Plant Factor from WUCOLS
⎟⎠
⎞⎜⎝
⎛+=071.0
700,24)62.0)(1.51(ETWU
= 1,102,116 gallons per year
Compare ETWU with MAWA: For this example MAWA = (51.1) (0.62) [(0.7 x 50,000) + (0.3 x 0)] =
1,108,870 gallons per year. The ETWU (1,102,116 gallons per year) is less than MAWA (1,108,870
gallons per year). In this example, the water budget complies with the MAWA.
(2) Example ETWU calculation: total landscape area is 50,000 square feet, 2,000 square feet of which is
planted with edible plants. The edible plant area is considered a Special Landscape Area (SLA). The
reference evapotranspiration value is 51.1 inches per year. The plant type, plant factor, and hydrozone
area are shown in the table below.
*Plant Factor from WUCOLS
⎟⎠
⎞⎜⎝
⎛+=000,271.0
500,23)62.0)(1.51(ETWU
= (31.68) (33,099 + 2,000)
= 1,111,936 gallons per year
Hydrozone
Plant Water
Use Type(s)
Plant
Factor
(PF)*
Hydrozone
Area (HA)
(square feet)
PF x HA
(square feet)
1 High 0.8 7,000 5,600
2 High 0.7 10,000 7,000
3 Medium 0.5 16,000 8,000
4 Low 0.3 7,000 2,100
5 Low 0.2 10,000 2,000
Sum24,700
Hydrozone
Plant Water
Use Type(s)
Plant
Factor
(PF)*
Hydrozone
Area (HA)
(square feet)
PF x HA
(square feet)
1 High 0.8 7,000 5,600
2 High 0.7 9,000 6,300
3 Medium 0.5 15,000 7,500
4 Low 0.3 7,000 2,100
5 Low 0.2 10,000 2,000
Sum23,500
6 SLA 1.0 2,000 2,000
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Compare ETWU with MAWA. For this example:
MAWA = (51.1) (0.62) [(0.7 x 50,000) + (0.3 x 2,000)]
= 31.68 x [35,000 + 600]
= 31.68 x 35,600
=1,127,808 gallons per year
The ETWU (1,111,936 gallons per year) is less than MAWA (1,127,808 gallons per year). For this
example, the water budget complies with the MAWA.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
§ 492.5 Soil Management Report.
(a) In order to reduce runoff and encourage healthy plant growth, a soil management report shall be
completed by the project applicant, or his/her designee, as follows:
(1) Submit soil samples to a laboratory for analysis and recommendations.
(A) Soil sampling shall be conducted in accordance with laboratory protocol, including protocols
regarding adequate sampling depth for the intended plants.
(B) The soil analysis may include:
1. soil texture;
2. infiltration rate determined by laboratory test or soil texture infiltration rate table;
3. pH;
4. total soluble salts;
5. sodium;
6. percent organic matter; and
7. recommendations.
(2) The project applicant, or his/her designee, shall comply with one of the following:
(A) If significant mass grading is not planned, the soil analysis report shall be submitted to the local
agency as part of the Landscape Documentation Package; or
(B) If significant mass grading is planned, the soil analysis report shall be submitted to the local agency
as part of the Certificate of Completion.
(3) The soil analysis report shall be made available, in a timely manner, to the professionals preparing
the landscape design plans and irrigation design plans to make any necessary adjustments to the design
plans.
(4) The project applicant, or his/her designee, shall submit documentation verifying implementation of
soil analysis report recommendations to the local agency with Certificate of Completion.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
§ 492.6 Landscape Design Plan.
(a) For the efficient use of water, a landscape shall be carefully designed and planned for the intended
function of the project. A landscape design plan meeting the following design criteria shall be submitted
as part of the Landscape Documentation Package.
(1) Plant Material
(A) Any plant may be selected for the landscape, providing the Estimated Total Water Use in the
landscape area does not exceed the Maximum Applied Water Allowance. To encourage the efficient use
of water, the following is highly recommended:
1. protection and preservation of native species and natural vegetation;
2. selection of water-conserving plant and turf species;
11
3. selection of plants based on disease and pest resistance;
4. selection of trees based on applicable local tree ordinances or tree shading guidelines; and
5. selection of plants from local and regional landscape program plant lists.
(B) Each hydrozone shall have plant materials with similar water use, with the exception of hydrozones
with plants of mixed water use, as specified in Section 492.7(a)(2)(D).
(C) Plants shall be selected and planted appropriately based upon their adaptability to the climatic,
geologic, and topographical conditions of the project site. To encourage the efficient use of water, the
following is highly recommended:
1. use the Sunset Western Climate Zone System which takes into account temperature, humidity,
elevation, terrain, latitude, and varying degrees of continental and marine influence on local climate;
2. recognize the horticultural attributes of plants (i.e., mature plant size, invasive surface roots) to
minimize damage to property or infrastructure [e.g., buildings, sidewalks, power lines]; and
3. consider the solar orientation for plant placement to maximize summer shade and winter solar gain.
(D) Turf is not allowed on slopes greater than 25% where the toe of the slope is adjacent to an
impermeable hardscape and where 25% means 1 foot of vertical elevation change for every 4 feet of
horizontal length (rise divided by run x 100 = slope percent).
(E) A landscape design plan for projects in fire-prone areas shall address fire safety and prevention. A
defensible space or zone around a building or structure is required per Public Resources Code Section
4291(a) and (b). Avoid fire-prone plant materials and highly flammable mulches.
(F) The use of invasive and/or noxious plant species is strongly discouraged.
(G) The architectural guidelines of a common interest development, which include community
apartment projects, condominiums, planned developments, and stock cooperatives, shall not prohibit or
include conditions that have the effect of prohibiting the use of low-water use plants as a group.
(2) Water Features
(A) Recirculating water systems shall be used for water features.
(B) Where available, recycled water shall be used as a source for decorative water features.
(C) Surface area of a water feature shall be included in the high water use hydrozone area of the water
budget calculation.
(D) Pool and spa covers are highly recommended.
(3) Mulch and Amendments
(A) A minimum two inch (2″) layer of mulch shall be applied on all exposed soil surfaces of planting
areas except in turf areas, creeping or rooting groundcovers, or direct seeding applications where mulch
is contraindicated.
(B) Stabilizing mulching products shall be used on slopes.
(C) The mulching portion of the seed/mulch slurry in hydro-seeded applications shall meet the mulching
requirement.
(D) Soil amendments shall be incorporated according to recommendations of the soil report and what is
appropriate for the plants selected (see Section 492.5).
(b) The landscape design plan, at a minimum, shall:
(1) delineate and label each hydrozone by number, letter, or other method;
(2) identify each hydrozone as low, moderate, high water, or mixed water use. Temporarily irrigated
areas of the landscape shall be included in the low water use hydrozone for the water budget calculation;
(3) identify recreational areas;
(4) identify areas permanently and solely dedicated to edible plants;
(5) identify areas irrigated with recycled water;
(6) identify type of mulch and application depth;
(7) identify soil amendments, type, and quantity;
(8) identify type and surface area of water features;
(9) identify hardscapes (pervious and non-pervious);
12
(10) identify location and installation details of any applicable stormwater best management practices
that encourage on-site retention and infiltration of stormwater. Stormwater best management practices
are encouraged in the landscape design plan and examples include, but are not limited to:
(A) infiltration beds, swales, and basins that allow water to collect and soak into the
ground;
(B) constructed wetlands and retention ponds that retain water, handle excess flow, and filter pollutants;
and
(C) pervious or porous surfaces (e.g., permeable pavers or blocks, pervious or porous concrete, etc.) that
minimize runoff.
(11) identify any applicable rain harvesting or catchment technologies (e.g., rain gardens, cisterns, etc.);
(12) contain the following statement: “I have complied with the criteria of the ordinance and applied
them for the efficient use of water in the landscape design plan”; and
(13) bear the signature of a licensed landscape architect, licensed landscape contractor, or any other
person authorized to design a landscape. (See Sections 5500.1, 5615, 5641, 5641.1, 5641.2, 5641.3,
5641.4, 5641.5, 5641.6, 6701, 7027.5 of the Business and Professions Code, Section 832.27 of Title16
of the California Code of Regulations, and Section 6721 of the Food and Agriculture Code.)
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code
and Section 1351, Civil Code.
§ 492.7 Irrigation Design Plan.
(a) For the efficient use of water, an irrigation system shall meet all the requirements listed in this
section and the manufacturers’ recommendations. The irrigation system and its related components shall
be planned and designed to allow for proper installation, management, and maintenance. An irrigation
design plan meeting the following design criteria shall be submitted as part of the Landscape
Documentation Package.
(1) System
(A) Dedicated landscape water meters are highly recommended on landscape areas smaller than 5,000
square feet to facilitate water management.
(B) Automatic irrigation controllers utilizing either evapotranspiration or soil moisture sensor data shall
be required for irrigation scheduling in all irrigation systems.
(C) The irrigation system shall be designed to ensure that the dynamic pressure at each emission device
is within the manufacturer’s recommended pressure range for optimal performance.
1. If the static pressure is above or below the required dynamic pressure of the irrigation system,
pressure-regulating devices such as inline pressure regulators, booster pumps, or other devices shall be
installed to meet the required dynamic pressure of the irrigation system.
2. Static water pressure, dynamic or operating pressure. and flow reading of the water supply shall be
measured at the point of connection. These pressure and flow measurements shall be conducted at the
design stage. If the measurements are not available at the design stage, the measurements shall be
conducted at installation.
(D) Sensors (rain, freeze, wind, etc.), either integral or auxiliary, that suspend or alter irrigation
operation during unfavorable weather conditions shall be required on all irrigation systems, as
appropriate for local climatic conditions. Irrigation should be avoided during windy or freezing weather
or during rain.
(E) Manual shut-off valves (such as a gate valve, ball valve, or butterfly valve) shall be required, as
close as possible to the point of connection of the water supply, to minimize water loss in case of an
emergency (such as a main line break) or routine repair.
13
(F) Backflow prevention devices shall be required to protect the water supply from contamination by the
irrigation system. A project applicant shall refer to the applicable local agency code (i.e., public health)
for additional backflow prevention requirements.
(G) High flow sensors that detect and report high flow conditions created by system damage or
malfunction are recommended.
(H) The irrigation system shall be designed to prevent runoff, low head drainage, overspray, or other
similar conditions where irrigation water flows onto non-targeted areas, such as adjacent property, non-
irrigated areas, hardscapes, roadways, or structures.
(I) Relevant information from the soil management plan, such as soil type and infiltration rate, shall be
utilized when designing irrigation systems.
(J) The design of the irrigation system shall conform to the hydrozones of the landscape design plan.
(K) The irrigation system must be designed and installed to meet, at a minimum, the irrigation efficiency
criteria as described in Section 492.4 regarding the Maximum Applied Water Allowance.
(L) It is highly recommended that the project applicant or local agency inquire with the local water
purveyor about peak water operating demands (on the water supply system) or water restrictions that
may impact the effectiveness of the irrigation system.
(M) In mulched planting areas, the use of low volume irrigation is required to maximize water
infiltration into the root zone.
(N) Sprinkler heads and other emission devices shall have matched precipitation rates, unless otherwise
directed by the manufacturer’s recommendations.
(O) Head to head coverage is recommended. However, sprinkler spacing shall be designed to achieve
the highest possible distribution uniformity using the manufacturer’s recommendations.
(P) Swing joints or other riser-protection components are required on all risers subject to damage that
are adjacent to high traffic areas.
(Q) Check valves or anti-drain valves are required for all irrigation systems.
(R) Narrow or irregularly shaped areas, including turf, less than eight (8) feet in width in any direction
shall be irrigated with subsurface irrigation or low volume irrigation system.
(S) Overhead irrigation shall not be permitted within 24 inches of any non-permeable surface. Allowable
irrigation within the setback from non-permeable surfaces may include drip, drip line, or other low flow
non-spray technology. The setback area may be planted or unplanted. The surfacing of the setback may
be mulch, gravel, or other porous material. These restrictions may be modified if:
1. the landscape area is adjacent to permeable surfacing and no runoff occurs; or
2. the adjacent non-permeable surfaces are designed and constructed to drain entirely to landscaping; or
3. the irrigation designer specifies an alternative design or technology, as part of the Landscape
Documentation Package and clearly demonstrates strict adherence to irrigation system design criteria in
Section 492.7 (a)(1)(H). Prevention of overspray and runoff must be confirmed during the irrigation
audit.
(T) Slopes greater than 25% shall not be irrigated with an irrigation system with a precipitation rate
exceeding 0.75 inches per hour. This restriction may be modified if the landscape designer specifies an
alternative design or technology, as part of the Landscape Documentation Package, and clearly
demonstrates no runoff or erosion will occur. Prevention of runoff and erosion must be confirmed during
the irrigation audit.
(2) Hydrozone
(A) Each valve shall irrigate a hydrozone with similar site, slope, sun exposure, soil conditions, and
plant materials with similar water use.
(B) Sprinkler heads and other emission devices shall be selected based on what is appropriate for the
plant type within that hydrozone.
(C) Where feasible, trees shall be placed on separate valves from shrubs, groundcovers, and turf.
(D) Individual hydrozones that mix plants of moderate and low water use, or moderate and high water
use, may be allowed if:
14
1. plant factor calculation is based on the proportions of the respective plant water uses and their plant
factor; or
2. the plant factor of the higher water using plant is used for calculations.
(E) Individual hydrozones that mix high and low water use plants shall not be permitted.
(F) On the landscape design plan and irrigation design plan, hydrozone areas shall be designated by
number, letter, or other designation. On the irrigation design plan, designate the areas irrigated by each
valve, and assign a number to each valve. Use this valve number in the Hydrozone Information Table
(see Appendix B Section A). This table can also assist with the irrigation audit and programming the
controller.
(b) The irrigation design plan, at a minimum, shall contain:
(1) location and size of separate water meters for landscape;
(2) location, type and size of all components of the irrigation system, including controllers, main and
lateral lines, valves, sprinkler heads, moisture sensing devices, rain switches, quick couplers, pressure
regulators, and backflow prevention devices;
(3) static water pressure at the point of connection to the public water supply;
(4) flow rate (gallons per minute), application rate (inches per hour), and design operating pressure
(pressure per square inch) for each station;
(5) recycled water irrigation systems as specified in Section 492.14;
(6) the following statement: “I have complied with the criteria of the ordinance and applied them
accordingly for the efficient use of water in the irrigation design plan”; and
(7) the signature of a licensed landscape architect, certified irrigation designer, licensed landscape
contractor, or any other person authorized to design an irrigation system. (See Sections 5500.1, 5615,
5641, 5641.1, 5641.2, 5641.3, 5641.4, 5641.5, 5641.6, 6701, 7027.5 of the Business and Professions
Code, Section 832.27 of Title 16 of the California Code of Regulations, and Section 6721 of the Food
and Agricultural Code.)
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
§ 492.8 Grading Design Plan.
(a) For the efficient use of water, grading of a project site shall be designed to minimize soil erosion,
runoff, and water waste. A grading plan shall be submitted as part of the Landscape Documentation
Package. A comprehensive grading plan prepared by a civil engineer for other local agency permits
satisfies this requirement.
(1) The project applicant shall submit a landscape grading plan that indicates finished configurations and
elevations of the landscape area including:
(A) height of graded slopes;
(B) drainage patterns;
(C) pad elevations;
(D) finish grade; and
(E) stormwater retention improvements, if applicable.
(2) To prevent excessive erosion and runoff, it is highly recommended that project applicants:
(A) grade so that all irrigation and normal rainfall remains within property lines and does not drain on to
non-permeable hardscapes;
(B) avoid disruption of natural drainage patterns and undisturbed soil; and
(C) avoid soil compaction in landscape areas.
(3) The grading design plan shall contain the following statement: “I have complied with the criteria of
the ordinance and applied them accordingly for the efficient use of water in the grading design plan” and
shall bear the signature of a licensed professional as authorized by law.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
15
§ 492.9 Certificate of Completion.
(a) The Certificate of Completion (see Appendix C for a sample certificate) shall include the following
six (6) elements:
(1) project information sheet that contains:
(A) date;
(B) project name;
(C) project applicant name, telephone, and mailing address;
(D) project address and location; and
(E) property owner name, telephone, and mailing address;
(2) certification by either the signer of the landscape design plan, the signer of the irrigation design plan,
or the licensed landscape contractor that the landscape project has been installed per the approved
Landscape Documentation Package;
(A) where there have been significant changes made in the field during construction, these “as-built” or
record drawings shall be included with the certification;
(3) irrigation scheduling parameters used to set the controller (see Section 492.10);
(4) landscape and irrigation maintenance schedule (see Section 492.11);
(5) irrigation audit report (see Section 492.12); and
(6) soil analysis report, if not submitted with Landscape Documentation Package, and documentation
verifying implementation of soil report recommendations (see Section 492.5).
(b) The project applicant shall:
(1) submit the signed Certificate of Completion to the local agency for review;
(2) ensure that copies of the approved Certificate of Completion are submitted to the local water
purveyor and property owner or his or her designee.
(c) The local agency shall:
(1) receive the signed Certificate of Completion from the project applicant;
(2) approve or deny the Certificate of Completion. If the Certificate of Completion is denied, the local
agency shall provide information to the project applicant regarding reapplication, appeal, or other
assistance.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
§ 492.10 Irrigation Scheduling.
(a) For the efficient use of water, all irrigation schedules shall be developed, managed, and evaluated to
utilize the minimum amount of water required to maintain plant health. Irrigation schedules shall meet
the following criteria:
(1) Irrigation scheduling shall be regulated by automatic irrigation controllers.
(2) Overhead irrigation shall be scheduled between 8:00 p.m. and 10:00 a.m. unless weather conditions
prevent it. If allowable hours of irrigation differ from the local water purveyor, the stricter of the two
shall apply. Operation of the irrigation system outside the normal watering window is allowed for
auditing and system maintenance.
(3) For implementation of the irrigation schedule, particular attention must be paid to irrigation run
times, emission device, flow rate, and current reference evapotranspiration, so that applied water meets
the Estimated Total Water Use. Total annual applied water shall be less than or equal to Maximum
Applied Water Allowance (MAWA). Actual irrigation schedules shall be regulated by automatic
irrigation controllers using current reference evapotranspiration data (e.g., CIMIS) or soil moisture
sensor data.
(4) Parameters used to set the automatic controller shall be developed and submitted for each of the
following:
(A) the plant establishment period;
16
(B) the established landscape; and
(C) temporarily irrigated areas.
(5) Each irrigation schedule shall consider for each station all of the following that apply:
(A) irrigation interval (days between irrigation);
(B) irrigation run times (hours or minutes per irrigation event to avoid runoff);
(C) number of cycle starts required for each irrigation event to avoid runoff;
(D) amount of applied water scheduled to be applied on a monthly basis;
(E) application rate setting;
(F) root depth setting;
(G) plant type setting;
(H) soil type;
(I) slope factor setting;
(J) shade factor setting; and
(K) irrigation uniformity or efficiency setting.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
§ 492.11 Landscape and Irrigation Maintenance Schedule.
(a) Landscapes shall be maintained to ensure water use efficiency. A regular maintenance schedule shall
be submitted with the Certificate of Completion.
(b) A regular maintenance schedule shall include, but not be limited to, routine inspection; adjustment
and repair of the irrigation system and its components; aerating and dethatching turf areas; replenishing
mulch; fertilizing; pruning; weeding in all landscape areas, and removing and obstruction to emission
devices. Operation of the irrigation system outside the normal watering window is allowed for auditing
and system maintenance.
(c) Repair of all irrigation equipment shall be done with the originally installed components or their
equivalents.
(d) A project applicant is encouraged to implement sustainable or environmentally-friendly practices for
overall landscape maintenance.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
§ 492.12 Irrigation Audit, Irrigation Survey, and Irrigation Water Use Analysis.
(a) All landscape irrigation audits shall be conducted by a certified landscape irrigation auditor.
(b) For new construction and rehabilitated landscape projects installed after January 1, 2010, as
described in Section 490.1:
(1) the project applicant shall submit an irrigation audit report with the Certificate of Completion to the
local agency that may include, but is not limited to: inspection, system tune-up, system test with
distribution uniformity, reporting overspray or run off that causes overland flow, and preparation of an
irrigation schedule;
(2) the local agency shall administer programs that may include, but not be limited to, irrigation water
use analysis, irrigation audits, and irrigation surveys for compliance with the Maximum Applied Water
Allowance.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
17
§ 492.13 Irrigation Efficiency.
(a) For the purpose of determining Maximum Applied Water Allowance, average irrigation efficiency is
assumed to be 0.71. Irrigation systems shall be designed, maintained, and managed to meet or exceed an
average landscape irrigation efficiency of 0.71.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
§ 492.14 Recycled Water.
(a) The installation of recycled water irrigation systems shall allow for the current and future use of
recycled water, unless a written exemption has been granted as described in Section 492.14(b).
(b) Irrigation systems and decorative water features shall use recycled water unless a written exemption
has been granted by the local water purveyor stating that recycled water meeting all public health codes
and standards is not available and will not be available for the foreseeable future.
(c) All recycled water irrigation systems shall be designed and operated in accordance with all
applicable local and State laws.
(d) Landscapes using recycled water are considered Special Landscape Areas. The ET Adjustment
Factor for Special Landscape Areas shall not exceed 1.0.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
§ 492.15 Stormwater Management.
(a) Stormwater management practices minimize runoff and increase infiltration which recharges
groundwater and improves water quality. Implementing stormwater best management practices into the
landscape and grading design plans to minimize runoff and to increase on-site retention and infiltration
are encouraged.
(b) Project applicants shall refer to the local agency or Regional Water Quality Control Board for
information on any applicable stormwater ordinances and stormwater management plans.
(c) Rain gardens, cisterns, and other landscapes features and practices that increase rainwater capture
and create opportunities for infiltration and/or onsite storage are recommended.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
§ 492.16 Public Education.
(a) Publications. Education is a critical component to promote the efficient use of water in landscapes.
The use of appropriate principles of design, installation, management and maintenance that save water is
encouraged in the community.
(1) A local agency shall provide information to owners of new, single-family residential homes
regarding the design, installation, management, and maintenance of water efficient landscapes.
(b) Model Homes. All model homes that are landscaped shall use signs and written information to
demonstrate the principles of water efficient landscapes described in this ordinance.
(1) Signs shall be used to identify the model as an example of a water efficient landscape featuring
elements such as hydrozones, irrigation equipment, and others that contribute to the overall water
efficient theme.
(2) Information shall be provided about designing, installing, managing, and maintaining water efficient
landscapes.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
18
§ 492.17 Environmental Review.
(a) The local agency must comply with the California Environmental Quality Act (CEQA), as
appropriate.
Note: Authority cited: Section 21082, Public Resources Code. Reference: Sections 21080, 21082, Public
Resources Code.
§ 493. Provisions for Existing Landscapes.
(a) A local agency may designate another agency, such as a water purveyor, to implement some or all of
the requirements contained in this ordinance. Local agencies may collaborate with water purveyors to
define each entity’s specific responsibilities relating to this ordinance.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
§ 493.1 Irrigation Audit, Irrigation Survey, and Irrigation Water Use Analysis.
(a) This section, 493.1, shall apply to all existing landscapes that were installed before January 1, 2010
and are over one acre in size.
(1) For all landscapes in 493.1(a) that have a water meter, the local agency shall administer programs
that may include, but not be limited to, irrigation water use analyses, irrigation surveys, and irrigation
audits to evaluate water use and provide recommendations as necessary to reduce landscape water use to
a level that does not exceed the Maximum Applied Water Allowance for existing landscapes. The
Maximum Applied Water Allowance for existing landscapes shall be calculated as: MAWA = (0.8)
(ETo)(LA)(0.62).
(2) For all landscapes in 493.1(a), that do not have a meter, the local agency shall administer programs
that may include, but not be limited to, irrigation surveys and irrigation audits to evaluate water use and
provide recommendations as necessary in order to prevent water waste.
(b) All landscape irrigation audits shall be conducted by a certified landscape irrigation auditor.
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
§ 493.2 Water Waste Prevention.
(a) Local agencies shall prevent water waste resulting from inefficient landscape irrigation by
prohibiting runoff from leaving the target landscape due to low head drainage, overspray, or other
similar conditions where water flows onto adjacent property, non-irrigated areas, walks, roadways,
parking lots, or structures. Penalties for violation of these prohibitions shall be established locally.
(b) Restrictions regarding overspray and runoff may be modified if:
(1) the landscape area is adjacent to permeable surfacing and no runoff occurs; or
(2) the adjacent non-permeable surfaces are designed and constructed to drain entirely to landscaping.
Note: Authority cited: Section 65594, Government Code. Reference: Section 65596, Government Code.
§ 494. Effective Precipitation.
(a) A local agency may consider Effective Precipitation (25% of annual precipitation) in tracking water
use and may use the following equation to calculate Maximum Applied Water Allowance:
MAWA= (ETo - Eppt) (0.62) [(0.7 x LA) + (0.3 x SLA)].
Note: Authority Cited: Section 65595, Government Code. Reference: Section 65596, Government Code.
19
Appendices.
Appendix A. Reference Evapotranspiration (ETo) Table.
20
Appendix A - Reference Evapotranspiration (ETo) Table*
County and City
Jan
Feb
Mar
Apr
May Jun Jul
Aug Sep Oct
Nov Dec
Annual
ETo
ALAMEDA
Fremont 1.5 1.9 3.4 4.7 5.4 6.3 6.7 6.0 4.5 3.4 1.8 1.5 47.0
Livermore 1.2 1.5 2.9 4.4 5.9 6.6 7.4 6.4 5.3 3.2 1.5 0.9 47.2
Oakland 1.5 1.5 2.8 3.9 5.1 5.3 6.0 5.5 4.8 3.1 1.4 0.9 41.8
Oakland Foothills 1.1 1.4 2.7 3.7 5.1 6.4 5.8 4.9 3.6 2.6 1.4 1.0 39.6
Pleasanton 0.8 1.5 2.9 4.4 5.6 6.7 7.4 6.4 4.7 3.3 1.5 1.0 46.2
Union City 1.4 1.8 3.1 4.2 5.4 5.9 6.4 5.7 4.4 3.1 1.5 1.2 44.2
ALPINE
Markleeville 0.7 0.9 2.0 3.5 5.0 6.1 7.3 6.4 4.4 2.6 1.2 0.5 40.6
AMADOR
Jackson 1.2 1.5 2.8 4.4 6.0 7.2 7.9 7.2 5.3 3.2 1.4 0.9 48.9
Shanandoah Valley 1.0 1.7 2.9 4.4 5.6 6.8 7.9 7.1 5.2 3.6 1.7 1.0 48.8
BUTTE
Chico 1.2 1.8 2.9 4.7 6.1 7.4 8.5 7.3 5.4 3.7 1.7 1.0 51.7
Durham 1.1 1.8 3.2 5.0 6.5 7.4 7.8 6.9 5.3 3.6 1.7 1.0 51.1
Gridley 1.2 1.8 3.0 4.7 6.1 7.7 8.5 7.1 5.4 3.7 1.7 1.0 51.9
Oroville 1.2 1.7 2.8 4.7 6.1 7.6 8.5 7.3 5.3 3.7 1.7 1.0 51.5
CALAVERAS
San Andreas 1.2 1.5 2.8 4.4 6.0 7.3 7.9 7.0 5.3 3.2 1.4 0.7 48.8
COLUSA
Colusa 1.0 1.7 3.4 5.0 6.4 7.6 8.3 7.2 5.4 3.8 1.8 1.1 52.8
Williams 1.2 1.7 2.9 4.5 6.1 7.2 8.5 7.3 5.3 3.4 1.6 1.0 50.8
CONTRA COSTA
Benicia 1.3 1.4 2.7 3.8 4.9 5.0 6.4 5.5 4.4 2.9 1.2 0.7 40.3
Brentwood 1.0 1.5 2.9 4.5 6.1 7.1 7.9 6.7 5.2 3.2 1.4 0.7 48.3
Concord 1.1 1.4 2.4 4.0 5.5 5.9 7.0 6.0 4.8 3.2 1.3 0.7 43.4
Courtland 0.9 1.5 2.9 4.4 6.1 6.9 7.9 6.7 5.3 3.2 1.4 0.7 48.0
Martinez 1.2 1.4 2.4 3.9 5.3 5.6 6.7 5.6 4.7 3.1 1.2 0.7 41.8
Moraga 1.2 1.5 3.4 4.2 5.5 6.1 6.7 5.9 4.6 3.2 1.6 1.0 44.9
Pittsburg 1.0 1.5 2.8 4.1 5.6 6.4 7.4 6.4 5.0 3.2 1.3 0.7 45.4
Walnut Creek 0.8 1.5 2.9 4.4 5.6 6.7 7.4 6.4 4.7 3.3 1.5 1.0 46.2
DEL NORTE
Crescent City 0.5 0.9 2.0 3.0 3.7 3.5 4.3 3.7 3.0 2.0 0.9 0.5 27.7
EL DORADO
Camino 0.9 1.7 2.5 3.9 5.9 7.2 7.8 6.8 5.1 3.1 1.5 0.9 47.3
FRESNO
Clovis 1.0 1.5 3.2 4.8 6.4 7.7 8.5 7.3 5.3 3.4 1.4 0.7 51.4
Coalinga 1.2 1.7 3.1 4.6 6.2 7.2 8.5 7.3 5.3 3.4 1.6 0.7 50.9
Firebaugh 1.0 1.8 3.7 5.7 7.3 8.1 8.2 7.2 5.5 3.9 2.0 1.1 55.4
FivePoints 1.3 2.0 4.0 6.1 7.7 8.5 8.7 8.0 6.2 4.5 2.4 1.2 60.4
Fresno 0.9 1.7 3.3 4.8 6.7 7.8 8.4 7.1 5.2 3.2 1.4 0.6 51.1
Fresno State 0.9 1.6 3.2 5.2 7.0 8.0 8.7 7.6 5.4 3.6 1.7 0.9 53.7
Friant 1.2 1.5 3.1 4.7 6.4 7.7 8.5 7.3 5.3 3.4 1.4 0.7 51.3
Kerman 0.9 1.5 3.2 4.8 6.6 7.7 8.4 7.2 5.3 3.4 1.4 0.7 51.2
Kingsburg 1.0 1.5 3.4 4.8 6.6 7.7 8.4 7.2 5.3 3.4 1.4 0.7 51.6
Mendota 1.5 2.5 4.6 6.2 7.9 8.6 8.8 7.5 5.9 4.5 2.4 1.5 61.7
Orange Cove 1.2 1.9 3.5 4.7 7.4 8.5 8.9 7.9 5.9 3.7 1.8 1.2 56.7
Panoche 1.1 2.0 4.0 5.6 7.8 8.5 8.3 7.3 5.6 3.9 1.8 1.2 57.2
Parlier 1.0 1.9 3.6 5.2 6.8 7.6 8.1 7.0 5.1 3.4 1.7 0.9 52.0
Reedley 1.1 1.5 3.2 4.7 6.4 7.7 8.5 7.3 5.3 3.4 1.4 0.7 51.3
Westlands 0.9 1.7 3.8 6.3 8.0 8.6 8.6 7.8 5.9 4.3 2.1 1.1 58.8
21
Appendix A - Reference Evapotranspiration (ETo) Table*
County and City Jan Feb Mar Apr May Jun Jul
Aug Sep Oct
Nov Dec
Annual
ETo
GLENN
Orland 1.1 1.8 3.4 5.0 6.4 7.5 7.9 6.7 5.3 3.9 1.8 1.4 52.1
Willows 1.2 1.7 2.9 4.7 6.1 7.2 8.5 7.3 5.3 3.6 1.7 1.0 51.3
HUMBOLDT
Eureka 0.5 1.1 2.0 3.0 3.7 3.7 3.7 3.7 3.0 2.0 0.9 0.5 27.5
Ferndale 0.5 1.1 2.0 3.0 3.7 3.7 3.7 3.7 3.0 2.0 0.9 0.5 27.5
Garberville 0.6 1.2 2.2 3.1 4.5 5.0 5.5 4.9 3.8 2.4 1.0 0.7 34.9
Hoopa 0.5 1.1 2.1 3.0 4.4 5.4 6.1 5.1 3.8 2.4 0.9 0.7 35.6
IMPERIAL
Brawley 2.8 3.8 5.9 8.0 10.4 11.5 11.7 10.0 8.4 6.2 3.5 2.1 84.2
Calipatria/Mulberry 2.4 3.2 5.1 6.8 8.6 9.2 9.2 8.6 7.0 5.2 3.1 2.3 70.7
El Centro 2.7 3.5 5.6 7.9 10.1 11.1 11.6 9.5 8.3 6.1 3.3 2.0 81.7
Holtville 2.8 3.8 5.9 7.9 10.4 11.6 12.0 10.0 8.6 6.2 3.5 2.1 84.7
Meloland 2.5 3.2 5.5 7.5 8.9 9.2 9.0 8.5 6.8 5.3 3.1 2.2 71.6
Palo Verde II 2.5 3.3 5.7 6.9 8.5 8.9 8.6 7.9 6.2 4.5 2.9 2.3 68.2
Seeley 2.7 3.5 5.9 7.7 9.7 10.1 9.3 8.3 6.9 5.5 3.4 2.2 75.4
Westmoreland 2.4 3.3 5.3 6.9 8.7 9.6 9.6 8.7 6.9 5.0 3.0 2.2 71.4
Yuma 2.5 3.4 5.3 6.9 8.7 9.6 9.6 8.7 6.9 5.0 3.0 2.2 71.6
INYO
Bishop 1.7 2.7 4.8 6.7 8.2 10.9 7.4 9.6 7.4 4.8 2.5 1.6 68.3
Death Valley Jct 2.2 3.3 5.4 7.7 9.8 11.1 11.4 10.1 8.3 5.4 2.9 1.7 79.1
Independence 1.7 2.7 3.4 6.6 8.5 9.5 9.8 8.5 7.1 3.9 2.0 1.5 65.2
Lower Haiwee Res. 1.8 2.7 4.4 7.1 8.5 9.5 9.8 8.5 7.1 4.2 2.6 1.5 67.6
Oasis 2.7 2.8 5.9 8.0 10.4 11.7 11.6 10.0 8.4 6.2 3.4 2.1 83.1
KERN
Arvin 1.2 1.8 3.5 4.7 6.6 7.4 8.1 7.3 5.3 3.4 1.7 1.0 51.9
Bakersfield 1.0 1.8 3.5 4.7 6.6 7.7 8.5 7.3 5.3 3.5 1.6 0.9 52.4
Bakersfield/Bonanza 1.2 2.2 3.7 5.7 7.4 8.2 8.7 7.8 5.7 4.0 2.1 1.2 57.9
Bakersfield/Greenlee 1.2 2.2 3.7 5.7 7.4 8.2 8.7 7.8 5.7 4.0 2.1 1.2 57.9
Belridge 1.4 2.2 4.1 5.5 7.7 8.5 8.6 7.8 6.0 3.8 2.0 1.5 59.2
Blackwells Corner 1.4 2.1 3.8 5.4 7.0 7.8 8.5 7.7 5.8 3.9 1.9 1.2 56.6
Buttonwillow 1.0 1.8 3.2 4.7 6.6 7.7 8.5 7.3 5.4 3.4 1.5 0.9 52.0
China Lake 2.1 3.2 5.3 7.7 9.2 10.0 11.0 9.8 7.3 4.9 2.7 1.7 74.8
Delano 0.9 1.8 3.4 4.7 6.6 7.7 8.5 7.3 5.4 3.4 1.4 0.7 52.0
Famoso 1.3 1.9 3.5 4.8 6.7 7.6 8.0 7.3 5.5 3.5 1.7 1.3 53.1
Grapevine 1.3 1.8 3.1 4.4 5.6 6.8 7.6 6.8 5.9 3.4 1.9 1.0 49.5
Inyokern 2.0 3.1 4.9 7.3 8.5 9.7 11.0 9.4 7.1 5.1 2.6 1.7 72.4
Isabella Dam 1.2 1.4 2.8 4.4 5.8 7.3 7.9 7.0 5.0 3.2 1.7 0.9 48.4
Lamont 1.3 2.4 4.4 4.6 6.5 7.0 8.8 7.6 5.7 3.7 1.6 0.8 54.4
Lost Hills 1.6 2.2 3.7 5.1 6.8 7.8 8.7 7.8 5.7 4.0 2.1 1.6 57.1
McFarland/Kern 1.2 2.1 3.7 5.6 7.3 8.0 8.3 7.4 5.6 4.1 2.0 1.2 56.5
Shafter 1.0 1.7 3.4 5.0 6.6 7.7 8.3 7.3 5.4 3.4 1.5 0.9 52.1
Taft 1.3 1.8 3.1 4.3 6.2 7.3 8.5 7.3 5.4 3.4 1.7 1.0 51.2
Tehachapi 1.4 1.8 3.2 5.0 6.1 7.7 7.9 7.3 5.9 3.4 2.1 1.2 52.9
KINGS
Caruthers 1.6 2.5 4.0 5.7 7.8 8.7 9.3 8.4 6.3 4.4 2.4 1.6 62.7
Corcoran 1.6 2.2 3.7 5.1 6.8 7.8 8.7 7.8 5.7 4.0 2.1 1.6 57.1
Hanford 0.9 1.5 3.4 5.0 6.6 7.7 8.3 7.2 5.4 3.4 1.4 0.7 51.5
Kettleman 1.1 2.0 4.0 6.0 7.5 8.5 9.1 8.2 6.1 4.5 2.2 1.1 60.2
Lemoore 0.9 1.5 3.4 5.0 6.6 7.7 8.3 7.3 5.4 3.4 1.4 0.7 51.7
Stratford 0.9 1.9 3.9 6.1 7.8 8.6 8.8 7.7 5.9 4.1 2.1 1.0 58.7
22
Appendix A - Reference Evapotranspiration (ETo) Table*
County and City Jan Feb Mar Apr May Jun Jul
Aug Sep Oct
Nov Dec
Annual
ETo
LAKE
Lakeport 1.1 1.3 2.6 3.5 5.1 6.0 7.3 6.1 4.7 2.9 1.2 0.9 42.8
Lower Lake 1.2 1.4 2.7 4.5 5.3 6.3 7.4 6.4 5.0 3.1 1.3 0.9 45.4
LASSEN
Buntingville 1.0 1.7 3.5 4.9 6.2 7.3 8.4 7.5 5.4 3.4 1.5 0.9 51.8
Ravendale 0.6 1.1 2.3 4.1 5.6 6.7 7.9 7.3 4.7 2.8 1.2 0.5 44.9
Susanville 0.7 1.0 2.2 4.1 5.6 6.5 7.8 7.0 4.6 2.8 1.2 0.5 44.0
LOS ANGELES
Burbank 2.1 2.8 3.7 4.7 5.1 6.0 6.6 6.7 5.4 4.0 2.6 2.0 51.7
Claremont 2.0 2.3 3.4 4.6 5.0 6.0 7.0 7.0 5.3 4.0 2.7 2.1 51.3
El Dorado 1.7 2.2 3.6 4.8 5.1 5.7 5.9 5.9 4.4 3.2 2.2 1.7 46.3
Glendale 2.0 2.2 3.3 3.8 4.7 4.8 5.7 5.6 4.3 3.3 2.2 1.8 43.7
Glendora 2.0 2.5 3.6 4.9 5.4 6.1 7.3 6.8 5.7 4.2 2.6 2.0 53.1
Gorman 1.6 2.2 3.4 4.6 5.5 7.4 7.7 7.1 5.9 3.6 2.4 1.1 52.4
Hollywood Hills 2.1 2.2 3.8 5.4 6.0 6.5 6.7 6.4 5.2 3.7 2.8 2.1 52.8
Lancaster 2.1 3.0 4.6 5.9 8.5 9.7 11.0 9.8 7.3 4.6 2.8 1.7 71.1
Long Beach 1.8 2.1 3.3 3.9 4.5 4.3 5.3 4.7 3.7 2.8 1.8 1.5 39.7
Los Angeles 2.2 2.7 3.7 4.7 5.5 5.8 6.2 5.9 5.0 3.9 2.6 1.9 50.1
Monrovia 2.2 2.3 3.8 4.3 5.5 5.9 6.9 6.4 5.1 3.2 2.5 2.0 50.2
Palmdale 2.0 2.6 4.6 6.2 7.3 8.9 9.8 9.0 6.5 4.7 2.7 2.1 66.2
Pasadena 2.1 2.7 3.7 4.7 5.1 6.0 7.1 6.7 5.6 4.2 2.6 2.0 52.3
Pearblossom 1.7 2.4 3.7 4.7 7.3 7.7 9.9 7.9 6.4 4.0 2.6 1.6 59.9
Pomona 1.7 2.0 3.4 4.5 5.0 5.8 6.5 6.4 4.7 3.5 2.3 1.7 47.5
Redondo Beach 2.2 2.4 3.3 3.8 4.5 4.7 5.4 4.8 4.4 2.8 2.4 2.0 42.6
San Fernando 2.0 2.7 3.5 4.6 5.5 5.9 7.3 6.7 5.3 3.9 2.6 2.0 52.0
Santa Clarita 2.8 2.8 4.1 5.6 6.0 6.8 7.6 7.8 5.8 5.2 3.7 3.2 61.5
Santa Monica 1.8 2.1 3.3 4.5 4.7 5.0 5.4 5.4 3.9 3.4 2.4 2.2 44.2
MADERA
Chowchilla 1.0 1.4 3.2 4.7 6.6 7.8 8.5 7.3 5.3 3.4 1.4 0.7 51.4
Madera 0.9 1.4 3.2 4.8 6.6 7.8 8.5 7.3 5.3 3.4 1.4 0.7 51.5
Raymond 1.2 1.5 3.0 4.6 6.1 7.6 8.4 7.3 5.2 3.4 1.4 0.7 50.5
MARIN
Black Point 1.1 1.7 3.0 4.2 5.2 6.2 6.6 5.8 4.3 2.8 1.3 0.9 43.0
Novato 1.3 1.5 2.4 3.5 4.4 6.0 5.9 5.4 4.4 2.8 1.4 0.7 39.8
Point San Pedro 1.1 1.7 3.0 4.2 5.2 6.2 6.6 5.8 4.3 2.8 1.3 0.9 43.0
San Rafael 1.2 1.3 2.4 3.3 4.0 4.8 4.8 4.9 4.3 2.7 1.3 0.7 35.8
MARIPOSA
Coulterville 1.1 1.5 2.8 4.4 5.9 7.3 8.1 7.0 5.3 3.4 1.4 0.7 48.8
Mariposa 1.1 1.5 2.8 4.4 5.9 7.4 8.2 7.1 5.0 3.4 1.4 0.7 49.0
Yosemite Village 0.7 1.0 2.3 3.7 5.1 6.5 7.1 6.1 4.4 2.9 1.1 0.6 41.4
MENDOCINO
Fort Bragg 0.9 1.3 2.2 3.0 3.7 3.5 3.7 3.7 3.0 2.3 1.2 0.7 29.0
Hopland 1.1 1.3 2.6 3.4 5.0 5.9 6.5 5.7 4.5 2.8 1.3 0.7 40.9
Point Arena 1.0 1.3 2.3 3.0 3.7 3.9 3.7 3.7 3.0 2.3 1.2 0.7 29.6
Sanel Valley 1.0 1.6 3.0 4.6 6.0 7.0 8.0 7.0 5.2 3.4 1.4 0.9 49.1
Ukiah 1.0 1.3 2.6 3.3 5.0 5.8 6.7 5.9 4.5 2.8 1.3 0.7 40.9
MERCED
Kesterson 0.9 1.7 3.4 5.5 7.3 8.2 8.6 7.4 5.5 3.8 1.8 0.9 55.1
Los Banos 1.0 1.5 3.2 4.7 6.1 7.4 8.2 7.0 5.3 3.4 1.4 0.7 50.0
Merced 1.0 1.5 3.2 4.7 6.6 7.9 8.5 7.2 5.3 3.4 1.4 0.7 51.5
23
Appendix A - Reference Evapotranspiration (ETo) Table*
County and City Jan Feb Mar Apr May Jun Jul
Aug Sep Oct
Nov Dec
Annual
ETo
MODOC
Modoc/Alturas 0.9 1.4 2.8 3.7 5.1 6.2 7.5 6.6 4.6 2.8 1.2 0.7 43.2
MONO
Bridgeport 0.7 0.9 2.2 3.8 5.5 6.6 7.4 6.7 4.7 2.7 1.2 0.5 43.0
MONTEREY
Arroyo Seco 1.5 2.0 3.7 5.4 6.3 7.3 7.2 6.7 5.0 3.9 2.0 1.6 52.6
Castroville 1.4 1.7 3.0 4.2 4.6 4.8 4.0 3.8 3.0 2.6 1.6 1.4 36.2
Gonzales 1.3 1.7 3.4 4.7 5.4 6.3 6.3 5.9 4.4 3.4 1.9 1.3 45.7
Greenfield 1.8 2.2 3.4 4.8 5.6 6.3 6.5 6.2 4.8 3.7 2.4 1.8 49.5
King City 1.7 2.0 3.4 4.4 4.4 5.6 6.1 6.7 6.5 5.2 2.2 1.3 49.6
King City-Oasis Rd. 1.4 1.9 3.6 5.3 6.5 7.3 7.4 6.8 5.1 4.0 2.0 1.5 52.7
Long Valley 1.5 1.9 3.2 4.1 5.8 6.5 7.3 6.7 5.3 3.6 2.0 1.2 49.1
Monterey 1.7 1.8 2.7 3.5 4.0 4.1 4.3 4.2 3.5 2.8 1.9 1.5 36.0
Pajaro 1.8 2.2 3.7 4.8 5.3 5.7 5.6 5.3 4.3 3.4 2.4 1.8 46.1
Salinas 1.6 1.9 2.7 3.8 4.8 4.7 5.0 4.5 4.0 2.9 1.9 1.3 39.1
Salinas North 1.2 1.5 2.9 4.1 4.6 5.2 4.5 4.3 3.2 2.8 1.5 1.2 36.9
San Ardo 1.0 1.7 3.1 4.5 5.9 7.2 8.1 7.1 5.1 3.1 1.5 1.0 49.0
San Juan 1.8 2.1 3.4 4.6 5.3 5.7 5.5 4.9 3.8 3.2 2.2 1.9 44.2
Soledad 1.7 2.0 3.4 4.4 5.5 5.4 6.5 6.2 5.2 3.7 2.2 1.5 47.7
NAPA
Angwin 1.8 1.9 3.2 4.7 5.8 7.3 8.1 7.1 5.5 4.5 2.9 2.1 54.9
Carneros 0.8 1.5 3.1 4.6 5.5 6.6 6.9 6.2 4.7 3.5 1.4 1.0 45.8
Oakville 1.0 1.5 2.9 4.7 5.8 6.9 7.2 6.4 4.9 3.5 1.6 1.2 47.7
St Helena 1.2 1.5 2.8 3.9 5.1 6.1 7.0 6.2 4.8 3.1 1.4 0.9 44.1
Yountville 1.3 1.7 2.8 3.9 5.1 6.0 7.1 6.1 4.8 3.1 1.5 0.9 44.3
NEVADA
Grass Valley 1.1 1.5 2.6 4.0 5.7 7.1 7.9 7.1 5.3 3.2 1.5 0.9 48.0
Nevada City 1.1 1.5 2.6 3.9 5.8 6.9 7.9 7.0 5.3 3.2 1.4 0.9 47.4
ORANGE
Irvine 2.2 2.5 3.7 4.7 5.2 5.9 6.3 6.2 4.6 3.7 2.6 2.3 49.6
Laguna Beach 2.2 2.7 3.4 3.8 4.6 4.6 4.9 4.9 4.4 3.4 2.4 2.0 43.2
Santa Ana 2.2 2.7 3.7 4.5 4.6 5.4 6.2 6.1 4.7 3.7 2.5 2.0 48.2
PLACER
Auburn 1.2 1.7 2.8 4.4 6.1 7.4 8.3 7.3 5.4 3.4 1.6 1.0 50.6
Blue Canyon 0.7 1.1 2.1 3.4 4.8 6.0 7.2 6.1 4.6 2.9 0.9 0.6 40.5
Colfax 1.1 1.5 2.6 4.0 5.8 7.1 7.9 7.0 5.3 3.2 1.4 0.9 47.9
Roseville 1.1 1.7 3.1 4.7 6.2 7.7 8.5 7.3 5.6 3.7 1.7 1.0 52.2
Soda Springs 0.7 0.7 1.8 3.0 4.3 5.3 6.2 5.5 4.1 2.5 0.7 0.7 35.4
Tahoe City 0.7 0.7 1.7 3.0 4.3 5.4 6.1 5.6 4.1 2.4 0.8 0.6 35.5
Truckee 0.7 0.7 1.7 3.2 4.4 5.4 6.4 5.7 4.1 2.4 0.8 0.6 36.2
PLUMAS
Portola 0.7 0.9 1.9 3.5 4.9 5.9 7.3 5.9 4.3 2.7 0.9 0.5 39.4
Quincy 0.7 0.9 2.2 3.5 4.9 5.9 7.3 5.9 4.4 2.8 1.2 0.5 40.2
RIVERSIDE
Beaumont 2.0 2.3 3.4 4.4 6.1 7.1 7.6 7.9 6.0 3.9 2.6 1.7 55.0
Blythe 2.4 3.3 5.3 6.9 8.7 9.6 9.6 8.7 6.9 5.0 3.0 2.2 71.4
Cathedral City 1.6 2.2 3.7 5.1 6.8 7.8 8.7 7.8 5.7 4.0 2.1 1.6 57.1
Coachella 2.9 4.4 6.2 8.4 10.5 11.9 12.3 10.1 8.9 6.2 3.8 2.4 88.1
Desert Center 2.9 4.1 6.4 8.5 11.0 12.1 12.2 11.1 9.0 6.4 3.9 2.6 90.0
Elsinore 2.1 2.8 3.9 4.4 5.9 7.1 7.6 7.0 5.8 3.9 2.6 1.9 55.0
Indio 3.1 3.6 6.5 8.3 10.5 11.0 10.8 9.7 8.3 5.9 3.7 2.7 83.9
24
Appendix A - Reference Evapotranspiration (ETo) Table*
County and City Jan Feb Mar Apr May Jun Jul
Aug Sep Oct
Nov Dec
Annual
ETo
RIVERSIDE
La Quinta 2.4 2.8 5.2 6.5 8.3 8.7 8.5 7.9 6.5 4.5 2.7 2.2 66.2
Mecca 2.6 3.3 5.7 7.2 8.6 9.0 8.8 8.2 6.8 5.0 3.2 2.4 70.8
Oasis 2.9 3.3 5.3 6.1 8.5 8.9 8.7 7.9 6.9 4.8 2.9 2.3 68.4
Palm Deser 2.5 3.4 5.3 6.9 8.7 9.6 9.6 8.7 6.9 5.0 3.0 2.2 71.6
Palm Springs 2.0 2.9 4.9 7.2 8.3 8.5 11.6 8.3 7.2 5.9 2.7 1.7 71.1
Rancho California 1.8 2.2 3.4 4.8 5.6 6.3 6.5 6.2 4.8 3.7 2.4 1.8 49.5
Rancho Mirage 2.4 3.3 5.3 6.9 8.7 9.6 9.6 8.7 6.9 5.0 3.0 2.2 71.4
Ripley 2.7 3.3 5.6 7.2 8.7 8.7 8.4 7.6 6.2 4.6 2.8 2.2 67.8
Salton Sea North 2.5 3.3 5.5 7.2 8.8 9.3 9.2 8.5 6.8 5.2 3.1 2.3 71.7
Temecula East II 2.3 2.4 4.1 4.9 6.4 7.0 7.8 7.4 5.7 4.1 2.6 2.2 56.7
Thermal 2.4 3.3 5.5 7.6 9.1 9.6 9.3 8.6 7.1 5.2 3.1 2.1 72.8
Riverside UC 2.5 2.9 4.2 5.3 5.9 6.6 7.2 6.9 5.4 4.1 2.9 2.6 56.4
Winchester 2.3 2.4 4.1 4.9 6.4 6.9 7.7 7.5 6.0 3.9 2.6 2.1 56.8
SACRAMENTO
Fair Oaks 1.0 1.6 3.4 4.1 6.5 7.5 8.1 7.1 5.2 3.4 1.5 1.0 50.5
Sacramento 1.0 1.8 3.2 4.7 6.4 7.7 8.4 7.2 5.4 3.7 1.7 0.9 51.9
Twitchell Island 1.2 1.8 3.9 5.3 7.4 8.8 9.1 7.8 5.9 3.8 1.7 1.2 57.9
SAN BENITO
Hollister 1.5 1.8 3.1 4.3 5.5 5.7 6.4 5.9 5.0 3.5 1.7 1.1 45.1
San Benito 1.2 1.6 3.1 4.6 5.6 6.4 6.9 6.5 4.8 3.7 1.7 1.2 47.2
San Juan Valley 1.4 1.8 3.4 4.5 6.0 6.7 7.1 6.4 5.0 3.5 1.8 1.4 49.1
SAN BERNARDINO
Baker 2.7 3.9 6.1 8.3 10.4 11.8 12.2 11.0 8.9 6.1 3.3 2.1 86.6
Barstow NE 2.2 2.9 5.3 6.9 9.0 10.1 9.9 8.9 6.8 4.8 2.7 2.1 71.7
Big Bear Lake 1.8 2.6 4.6 6.0 7.0 7.6 8.1 7.4 5.4 4.1 2.4 1.8 58.6
Chino 2.1 2.9 3.9 4.5 5.7 6.5 7.3 7.1 5.9 4.2 2.6 2.0 54.6
Crestline 1.5 1.9 3.3 4.4 5.5 6.6 7.8 7.1 5.4 3.5 2.2 1.6 50.8
Lake Arrowhead 1.8 2.6 4.6 6.0 7.0 7.6 8.1 7.4 5.4 4.1 2.4 1.8 58.6
Lucerne Valley 2.2 2.9 5.1 6.5 9.1 11.0 11.4 9.9 7.4 5.0 3.0 1.8 75.3
Needles 3.2 4.2 6.6 8.9 11.0 12.4 12.8 11.0 8.9 6.6 4.0 2.7 92.1
Newberry Springs 2.1 2.9 5.3 8.4 9.8 10.9 11.1 9.9 7.6 5.2 3.1 2.0 78.2
San Bernardino 2.0 2.7 3.8 4.6 5.7 6.9 7.9 7.4 5.9 4.2 2.6 2.0 55.6
Twentynine Palms 2.6 3.6 5.9 7.9 10.1 11.2 11.2 10.3 8.6 5.9 3.4 2.2 82.9
Victorville 2.0 2.6 4.6 6.2 7.3 8.9 9.8 9.0 6.5 4.7 2.7 2.1 66.2
SAN DIEGO
Chula Vista 2.2 2.7 3.4 3.8 4.9 4.7 5.5 4.9 4.5 3.4 2.4 2.0 44.2
Escondido SPV 2.4 2.6 3.9 4.7 5.9 6.5 7.1 6.7 5.3 3.9 2.8 2.3 54.2
Miramar 2.3 2.5 3.7 4.1 5.1 5.4 6.1 5.8 4.5 3.3 2.4 2.1 47.1
Oceanside 2.2 2.7 3.4 3.7 4.9 4.6 4.6 5.1 4.1 3.3 2.4 2.0 42.9
Otay Lake 2.3 2.7 3.9 4.6 5.6 5.9 6.2 6.1 4.8 3.7 2.6 2.2 50.4
Pine Valley 1.5 2.4 3.8 5.1 6.0 7.0 7.8 7.3 6.0 4.0 2.2 1.7 54.8
Ramona 2.1 2.1 3.4 4.6 5.2 6.3 6.7 6.8 5.3 4.1 2.8 2.1 51.6
San Diego 2.1 2.4 3.4 4.6 5.1 5.3 5.7 5.6 4.3 3.6 2.4 2.0 46.5
Santee 2.1 2.7 3.7 4.5 5.5 6.1 6.6 6.2 5.4 3.8 2.6 2.0 51.1
Torrey Pines 2.2 2.3 3.4 3.9 4.0 4.1 4.6 4.7 3.8 2.8 2.0 2.0 39.8
Warner Springs 1.6 2.7 3.7 4.7 5.7 7.6 8.3 7.7 6.3 4.0 2.5 1.3 56.0
SAN FRANCISCO
San Francisco 1.5 1.3 2.4 3.0 3.7 4.6 4.9 4.8 4.1 2.8 1.3 0.7 35.1
SAN JOAQUIN
Farmington 1.5 1.5 2.9 4.7 6.2 7.6 8.1 6.8 5.3 3.3 1.4 0.7 50.0
25
Appendix A - Reference Evapotranspiration (ETo) Table*
County and City Jan Feb Mar Apr May Jun Jul
Aug Sep Oct
Nov Dec
Annual
ETo
SAN JOAQUIN
Lodi West 1.0 1.6 3.3 4.3 6.3 6.9 7.3 6.4 4.5 3.0 1.4 0.8 46.7
Manteca 0.9 1.7 3.4 5.0 6.5 7.5 8.0 7.1 5.2 3.3 1.6 0.9 51.2
Stockton 0.8 1.5 2.9 4.7 6.2 7.4 8.1 6.8 5.3 3.2 1.4 0.6 49.1
Tracy 1.0 1.5 2.9 4.5 6.1 7.3 7.9 6.7 5.3 3.2 1.3 0.7 48.5
SAN LUIS OBISPO
Arroyo Grande 2.0 2.2 3.2 3.8 4.3 4.7 4.3 4.6 3.8 3.2 2.4 1.7 40.0
Atascadero 1.2 1.5 2.8 3.9 4.5 6.0 6.7 6.2 5.0 3.2 1.7 1.0 43.7
Morro Bay 2.0 2.2 3.1 3.5 4.3 4.5 4.6 4.6 3.8 3.5 2.1 1.7 39.9
Nipomo 2.2 2.5 3.8 5.1 5.7 6.2 6.4 6.1 4.9 4.1 2.9 2.3 52.1
Paso Robles 1.6 2.0 3.2 4.3 5.5 6.3 7.3 6.7 5.1 3.7 2.1 1.4 49.0
San Luis Obispo 2.0 2.2 3.2 4.1 4.9 5.3 4.6 5.5 4.4 3.5 2.4 1.7 43.8
San Miguel 1.6 2.0 3.2 4.3 5.0 6.4 7.4 6.8 5.1 3.7 2.1 1.4 49.0
San Simeon 2.0 2.0 2.9 3.5 4.2 4.4 4.6 4.3 3.5 3.1 2.0 1.7 38.1
SAN MATEO
Hal Moon Bay 1.5 1.7 2.4 3.0 3.9 4.3 4.3 4.2 3.5 2.8 1.3 1.0 33.7
Redwood City 1.5 1.8 2.9 3.8 5.2 5.3 6.2 5.6 4.8 3.1 1.7 1.0 42.8
Woodside 1.8 2.2 3.4 4.8 5.6 6.3 6.5 6.2 4.8 3.7 2.4 1.8 49.5
SANTA BARBARA
Betteravia 2.1 2.6 4.0 5.2 6.0 5.9 5.8 5.4 4.1 3.3 2.7 2.1 49.1
Carpenteria 2.0 2.4 3.2 3.9 4.8 5.2 5.5 5.7 4.5 3.4 2.4 2.0 44.9
Cuyama 2.1 2.4 3.8 5.4 6.9 7.9 8.5 7.7 5.9 4.5 2.6 2.0 59.7
Goleta 2.1 2.5 3.9 5.1 5.7 5.7 5.4 5.4 4.2 3.2 2.8 2.2 48.1
Goleta Foothills 2.3 2.6 3.7 5.4 5.3 5.6 5.5 5.7 4.5 3.9 2.8 2.3 49.6
Guadalupe 2.0 2.2 3.2 3.7 4.9 4.6 4.5 4.6 4.1 3.3 2.4 1.7 41.1
Lompoc 2.0 2.2 3.2 3.7 4.8 4.6 4.9 4.8 3.9 3.2 2.4 1.7 41.1
Los Alamos 1.8 2.0 3.2 4.1 4.9 5.3 5.7 5.5 4.4 3.7 2.4 1.6 44.6
Santa Barbara 2.0 2.5 3.2 3.8 4.6 5.1 5.5 4.5 3.4 2.4 1.8 1.8 40.6
Santa Maria 1.8 2.3 3.7 5.1 5.7 5.8 5.6 5.3 4.2 3.5 2.4 1.9 47.4
Santa Ynez 1.7 2.2 3.5 5.0 5.8 6.2 6.4 6.0 4.5 3.6 2.2 1.7 48.7
Sisquoc 2.1 2.5 3.8 4.1 6.1 6.3 6.4 5.8 4.7 3.4 2.3 1.8 49.2
Solvang 2.0 2.0 3.3 4.3 5.0 5.6 6.1 5.6 4.4 3.7 2.2 1.6 45.6
SANTA CLARA
Gilroy 1.3 1.8 3.1 4.1 5.3 5.6 6.1 5.5 4.7 3.4 1.7 1.1 43.6
Los Gatos 1.5 1.8 2.8 3.9 5.0 5.6 6.2 5.5 4.7 3.2 1.7 1.1 42.9
Morgan Hill 1.5 1.8 3.4 4.2 6.3 7.0 7.1 6.0 5.1 3.7 1.9 1.4 49.5
Palo Alto 1.5 1.8 2.8 3.8 5.2 5.3 6.2 5.6 5.0 3.2 1.7 1.0 43.0
San Jose 1.5 1.8 3.1 4.1 5.5 5.8 6.5 5.9 5.2 3.3 1.8 1.0 45.3
SANTA CRUZ
De Laveaga 1.4 1.9 3.3 4.7 4.9 5.3 5.0 4.8 3.6 3.0 1.6 1.3 40.8
Green Valley Rd 1.2 1.8 3.2 4.5 4.6 5.4 5.2 5.0 3.7 3.1 1.6 1.3 40.6
Santa Cruz 1.5 1.8 2.6 3.5 4.3 4.4 4.8 4.4 3.8 2.8 1.7 1.2 36.6
Watsonville 1.5 1.8 2.7 3.7 4.6 4.5 4.9 4.2 4.0 2.9 1.8 1.2 37.7
Webb 1.8 2.2 3.7 4.8 5.3 5.7 5.6 5.3 4.3 3.4 2.4 1.8 46.2
SHASTA
Burney 0.7 1.0 2.1 3.5 4.9 5.9 7.4 6.4 4.4 2.9 0.9 0.6 40.9
Fall River Mills 0.6 1.0 2.1 3.7 5.0 6.1 7.8 6.7 4.6 2.8 0.9 0.5 41.8
Glenburn 0.6 1.0 2.1 3.7 5.0 6.3 7.8 6.7 4.7 2.8 0.9 0.6 42.1
McArthur 0.7 1.4 2.9 4.2 5.6 6.9 8.2 7.2 5.0 3.0 1.1 0.6 46.8
Redding 1.2 1.4 2.6 4.1 5.6 7.1 8.5 7.3 5.3 3.2 1.4 0.9 48.8
26
Appendix A - Reference Evapotranspiration (ETo) Table*
County and City Jan Feb Mar Apr May Jun Jul
Aug Sep Oct
Nov Dec
Annual
ETo
SIERRA
Downieville 0.7 1.0 2.3 3.5 5.0 6.0 7.4 6.2 4.7 2.8 0.9 0.6 41.3
Sierraville 0.7 1.1 2.2 3.2 4.5 5.9 7.3 6.4 4.3 2.6 0.9 0.5 39.6
SISKIYOU
Happy Camp 0.5 0.9 2.0 3.0 4.3 5.2 6.1 5.3 4.1 2.4 0.9 0.5 35.1
MacDoel 1.0 1.7 3.1 4.5 5.9 7.2 8.1 7.1 5.1 3.1 1.5 1.0 49.0
Mt Shasta 0.5 0.9 2.0 3.0 4.5 5.3 6.7 5.7 4.0 2.2 0.7 0.5 36.0
Tule lake FS 0.7 1.3 2.7 4.0 5.4 6.3 7.1 6.4 4.7 2.8 1.0 0.6 42.9
Weed 0.5 0.9 2.0 2.5 4.5 5.3 6.7 5.5 3.7 2.0 0.9 0.5 34.9
Yreka 0.6 0.9 2.1 3.0 4.9 5.8 7.3 6.5 4.3 2.5 0.9 0.5 39.2
SOLANO
Dixon 0.7 1.4 3.2 5.2 6.3 7.6 8.2 7.2 5.5 4.3 1.6 1.1 52.1
Fairfield 1.1 1.7 2.8 4.0 5.5 6.1 7.8 6.0 4.8 3.1 1.4 0.9 45.2
Hastings Tract 1.6 2.2 3.7 5.1 6.8 7.8 8.7 7.8 5.7 4.0 2.1 1.6 57.1
Putah Creek 1.0 1.6 3.2 4.9 6.1 7.3 7.9 7.0 5.3 3.8 1.8 1.2 51.0
Rio Vista 0.9 1.7 2.8 4.4 5.9 6.7 7.9 6.5 5.1 3.2 1.3 0.7 47.0
Suisun Valley 0.6 1.3 3.0 4.7 5.8 7.0 7.7 6.8 5.3 3.8 1.4 0.9 48.3
Winters 0.9 1.7 3.3 5.0 6.4 7.5 7.9 7.0 5.2 3.5 1.6 1.0 51.0
SONOMA
Bennett Valley 1.1 1.7 3.2 4.1 5.5 6.5 6.6 5.7 4.5 3.1 1.5 0.9 44.4
Cloverdale 1.1 1.4 2.6 3.4 5.0 5.9 6.2 5.6 4.5 2.8 1.4 0.7 40.7
Fort Ross 1.2 1.4 2.2 3.0 3.7 4.5 4.2 4.3 3.4 2.4 1.2 0.5 31.9
Healdsburg 1.2 1.5 2.4 3.5 5.0 5.9 6.1 5.6 4.5 2.8 1.4 0.7 40.8
Lincoln 1.2 1.7 2.8 4.7 6.1 7.4 8.4 7.3 5.4 3.7 1.9 1.2 51.9
Petaluma 1.2 1.5 2.8 3.7 4.6 5.6 4.6 5.7 4.5 2.9 1.4 0.9 39.6
Santa Rosa 1.2 1.7 2.8 3.7 5.0 6.0 6.1 5.9 4.5 2.9 1.5 0.7 42.0
Valley of the Moon 1.0 1.6 3.0 4.5 5.6 6.6 7.1 6.3 4.7 3.3 1.5 1.0 46.1
Windsor 0.9 1.6 3.0 4.5 5.5 6.5 6.5 5.9 4.4 3.2 1.4 1.0 44.2
STANISLAUS
Denair 1.0 1.9 3.6 4.7 7.0 7.9 8.0 6.1 5.3 3.4 1.5 1.0 51.4
La Grange 1.2 1.5 3.1 4.7 6.2 7.7 8.5 7.3 5.3 3.4 1.4 0.7 51.2
Modesto 0.9 1.4 3.2 4.7 6.4 7.7 8.1 6.8 5.0 3.4 1.4 0.7 49.7
Newman 1.0 1.5 3.2 4.6 6.2 7.4 8.1 6.7 5.0 3.4 1.4 0.7 49.3
Oakdale 1.2 1.5 3.2 4.7 6.2 7.7 8.1 7.1 5.1 3.4 1.4 0.7 50.3
Patterson 1.3 2.1 4.2 5.4 7.9 8.6 8.2 6.6 5.8 4.0 1.9 1.3 57.3
Turlock 0.9 1.5 3.2 4.7 6.5 7.7 8.2 7.0 5.1 3.4 1.4 0.7 50.2
SUTTER
Nicolaus 0.9 1.6 3.2 4.9 6.3 7.5 8.0 6.9 5.2 3.4 1.5 0.9 50.2
Yuba City 1.3 2.1 2.8 4.4 5.7 7.2 7.1 6.1 4.7 3.2 1.2 0.9 46.7
TEHAMA
Corning 1.2 1.8 2.9 4.5 6.1 7.3 8.1 7.2 5.3 3.7 1.7 1.1 50.7
Gerber 1.0 1.8 3.5 5.0 6.6 7.9 8.7 7.4 5.8 4.1 1.8 1.1 54.7
Gerber Dryland 0.9 1.6 3.2 4.7 6.7 8.4 9.0 7.9 6.0 4.2 2.0 1.0 55.5
Red Bluff 1.2 1.8 2.9 4.4 5.9 7.4 8.5 7.3 5.4 3.5 1.7 1.0 51.1
TRINITY
Hay Fork 0.5 1.1 2.3 3.5 4.9 5.9 7.0 6.0 4.5 2.8 0.9 0.7 40.1
Weaverville 0.6 1.1 2.2 3.3 4.9 5.9 7.3 6.0 4.4 2.7 0.9 0.7 40.0
TULARE
Alpaugh 0.9 1.7 3.4 4.8 6.6 7.7 8.2 7.3 5.4 3.4 1.4 0.7 51.6
Badger 1.0 1.3 2.7 4.1 6.0 7.3 7.7 7.0 4.8 3.3 1.4 0.7 47.3
Delano 1.1 1.9 4.0 4.9 7.2 7.9 8.1 7.3 5.4 3.2 1.5 1.2 53.6
27
Appendix A - Reference Evapotranspiration (ETo) Table*
County and City Jan Feb Mar Apr May Jun Jul
Aug Sep Oct
Nov Dec
Annual
ETo
TULARE
Dinuba 1.1 1.5 3.2 4.7 6.2 7.7 8.5 7.3 5.3 3.4 1.4 0.7 51.2
Lindcove 0.9 1.6 3.0 4.8 6.5 7.6 8.1 7.2 5.2 3.4 1.6 0.9 50.6
Porterville 1.2 1.8 3.4 4.7 6.6 7.7 8.5 7.3 5.3 3.4 1.4 0.7 52.1
Visalia 0.9 1.7 3.3 5.1 6.8 7.7 7.9 6.9 4.9 3.2 1.5 0.8 50.7
TUOLUMNE
Groveland 1.1 1.5 2.8 4.1 5.7 7.2 7.9 6.6 5.1 3.3 1.4 0.7 47.5
Sonora 1.1 1.5 2.8 4.1 5.8 7.2 7.9 6.7 5.1 3.2 1.4 0.7 47.6
VENTURA
Camarillo 2.2 2.5 3.7 4.3 5.0 5.2 5.9 5.4 4.2 3.0 2.5 2.1 46.1
Oxnard 2.2 2.5 3.2 3.7 4.4 4.6 5.4 4.8 4.0 3.3 2.4 2.0 42.3
Piru 2.8 2.8 4.1 5.6 6.0 6.8 7.6 7.8 5.8 5.2 3.7 3.2 61.5
Port Hueneme 2.0 2.3 3.3 4.6 4.9 4.9 4.9 5.0 3.7 3.2 2.5 2.2 43.5
Thousand Oaks 2.2 2.6 3.4 4.5 5.4 5.9 6.7 6.4 5.4 3.9 2.6 2.0 51.0
Ventura 2.2 2.6 3.2 3.8 4.6 4.7 5.5 4.9 4.1 3.4 2.5 2.0 43.5
YOLO
Bryte 0.9 1.7 3.3 5.0 6.4 7.5 7.9 7.0 5.2 3.5 1.6 1.0 51.0
Davis 1.0 1.9 3.3 5.0 6.4 7.6 8.2 7.1 5.4 4.0 1.8 1.0 52.5
Esparto 1.0 1.7 3.4 5.5 6.9 8.1 8.5 7.5 5.8 4.2 2.0 1.2 55.8
Winters 1.7 1.7 2.9 4.4 5.8 7.1 7.9 6.7 5.3 3.3 1.6 1.0 49.4
Woodland 1.0 1.8 3.2 4.7 6.1 7.7 8.2 7.2 5.4 3.7 1.7 1.0 51.6
Zamora 1.1 1.9 3.5 5.2 6.4 7.4 7.8 7.0 5.5 4.0 1.9 1.2 52.8
YUBA
Browns Valley 1.0 1.7 3.1 4.7 6.1 7.5 8.5 7.6 5.7 4.1 2.0 1.1 52.9
Brownsville 1.1 1.4 2.6 4.0 5.7 6.8 7.9 6.8 5.3 3.4 1.5 0.9 47.4
* The values in this table were derived from:
1) California Irrigation Management Information System (CIMIS);
2) Reference EvapoTranspiration Zones Map, UC Dept. of Land, Air & Water Resources and California
Dept of Water Resources 1999; and
3) Reference Evapotranspiration for California, University of California, Department of Agriculture and
Natural Resources
(1987) Bulletin 1922, 4) Determining Daily Reference Evapotranspiration, Cooperative Extension UC
Division of Agriculture and Natural Resources (1987), Publication Leaflet 21426
28
Appendix B – Sample Water Efficient Landscape Worksheet.
WATER EFFICIENT LANDSCAPE WORKSHEET
This worksheet is filled out by the project applicant and it is a required element of the Landscape Documentation Package.
Please complete all sections (A and B) of the worksheet.
SECTION A. HYDROZONE INFORMATION TABLE
Please complete the hydrozone table(s) for each hydrozone. Use as many tables as necessary to provide the
square footage of landscape area per hydrozone.
Hydrozone* Zone or
Valve Irrigation
Method** Area
(Sq. Ft.) % of
Landscape Area
Total 100%
* Hydrozone
HW = High Water Use Plants
MW = Moderate Water Use Plants
LW = Low Water Use Plants
**Irrigation Method
MS = Micro-spray
S = Spray
R = Rotor
B= Bubbler
D= Drip
O = Other
29
SECTION B. WATER BUDGET CALCULATIONS
Section B1. Maximum Applied Water Allowance (MAWA)
The project's Maximum Applied Water Allowance shall be calculated using this equation:
MAWA = (ETo) (0.62) [(0.7 x LA) + (0.3 x SLA)]
where:
MAWA = Maximum Applied Water Allowance (gallons per year)
ETo = Reference Evapotranspiration from Appendix A (inches per year)
0.7 = ET Adjustment Factor (ETAF)
LA = Landscaped Area includes Special Landscape Area (square feet)
0.62 = Conversion factor (to gallons per square foot)
SLA = Portion of the landscape area identified as Special Landscape Area (square feet)
0.3 = the additional ET Adjustment Factor for Special Landscape Area (1.0 - 0.7 = 0.3)
Maximum Applied Water Allowance = ________________________gallons per year
Show calculations.
Effective Precipitation (Eppt)
If considering Effective Precipitation, use 25% of annual precipitation. Use the following equation to calculate
Maximum Applied Water Allowance:
MAWA= (ETo – Eppt) (0.62) [(0.7 x LA) + (0.3 x SLA)]
Maximum Applied Water Allowance = ________________________gallons per year
Show calculations.
30
Section B2. Estimated Total Water Use (ETWU)
The project’s Estimated Total Water Use is calculated using the following formula:
where:
ETWU = Estimated total water use per year (gallons per year)
ETo = Reference Evapotranspiration (inches per year)
PF = Plant Factor from WUCOLS (see Definitions)
HA = Hydrozone Area [high, medium, and low water use areas] (square feet)
SLA = Special Landscape Area (square feet)
0.62 = Conversion Factor (to gallons per square foot)
IE = Irrigation Efficiency (minimum 0.71)
Hydrozone Table for Calculating ETWU
Please complete the hydrozone table(s). Use as many tables as necessary.
Estimated Total Water Use = _________________________gallons
Show calculations.
Hydrozone
Plant Water
Use Type(s)
Plant
Factor (PF)
Area (HA)
(square feet)
PF x HA
(square feet)
Sum
SLA
⎟⎠
⎞⎜⎝
⎛+=SLAIE
HAxPFEToETWU)62.0)((
31
Appendix C – Sample Certificate of Completion.
CERTIFICATE OF COMPLETION
This certificate is filled out by the project applicant upon completion of the landscape project.
PART 1. PROJECT INFORMATION SHEET
Date
Project Name
Telephone No.
Name of Project Applicant
Fax No.
Title
Email Address
Company Street Address
City State Zip Code
Project Address and Location:
Street Address
Parcel, tract or lot number, if available.
City
State
Zip Code
Latitude/Longitude (optional)
Property Owner or his/her designee:
Telephone No.
Name
Fax No.
Title Email Address
Company Street Address
City
State Zip Code
Property Owner
“I/we certify that I/we have received copies of all the documents within the Landscape Documentation Package
and the Certificate of Completion and that it is our responsibility to see that the project is maintained in
accordance with the Landscape and Irrigation Maintenance Schedule.”
______________________________________________________________________________
Property Owner Signature Date
Please answer the questions below:
1. Date the Landscape Documentation Package was submitted to the local agency_____________
2. Date the Landscape Documentation Package was approved by the local agency_____________
3. Date that a copy of the Water Efficient Landscape Worksheet (including the Water Budget Calculation) was
submitted to the local water purveyor_____________
32
PART 2. CERTIFICATION OF INSTALLATION ACCORDING TO THE LANDSCAPE
DOCUMENTATION PACKAGE
“I/we certify that based upon periodic site observations, the work has been substantially completed in accordance
with the ordinance and that the landscape planting and irrigation installation conform with the criteria and
specifications of the approved Landscape Documentation Package.”
Signature*
Date
Telephone No.
Name (print)
Fax No.
Title
Email Address
License No. or Certification No.
Company Street Address
City
State Zip Code
*Signer of the landscape design plan, signer of the irrigation plan, or a licensed landscape contractor.
PART 3. IRRIGATION SCHEDULING
Attach parameters for setting the irrigation schedule on controller per ordinance Section 492.10.
PART 4. SCHEDULE OF LANDSCAPE AND IRRIGATION MAINTENANCE
Attach schedule of Landscape and Irrigation Maintenance per ordinance Section 492.11.
PART 5. LANDSCAPE IRRIGATION AUDIT REPORT
Attach Landscape Irrigation Audit Report per ordinance Section 492.12.
PART 6. SOIL MANAGEMENT REPORT
Attach soil analysis report, if not previously submitted with the Landscape Documentation Package per ordinance
Section 492.5.
Attach documentation verifying implementation of recommendations from soil analysis report per ordinance
Section 492.5.
Assembly Bill No. 1881
CHAPTER 559
An act to add Section 1353.8 to the Civil Code, to repeal and add
Article 10.8 (commencing with Section 65591) of Chapter 3 of Division 1
of Title 7 of the Government Code, to add Section 25401.9 to the Public
Resources Code, and to add Article 4.5 (commencing with Section 535) to
Chapter 8 of Division 1 of the Water Code, relating to water conservation.
[Approved by Governor September 28, 2006. Filed with
Secretary of State September 28, 2006.]
legislative counsel’s digest
AB 1881, Laird.Water conservation.
(1) Existing law, the Davis-Sterling Common Interest Development
Act, defines and regulates common interest developments, which include
community apartment projects, condominium projects, planned
developments, and stock cooperatives.
This bill would provide that the architectural guidelines of a common
interest development shall not prohibit or include conditions that have the
effect of prohibiting the use of low water-using plants as a group.
(2) The Water Conservation in Landscaping Act requires the
Department of Water Resources to appoint an advisory task force to work
with the department to draft a model local water efficient landscape
ordinance that local agencies may adopt, requires the task force to submit
the ordinance to the department on or before May 1, 1991, and requires the
task force to cease to exist on the date the department adopts the model
ordinance or January 1, 1992, whichever occurs first. The act requires the
department, not later than January 1, 1992, to adopt a model local water
efficient landscape ordinance which each local agency may adopt. The act
makes the model local water efficient landscape ordinance adopted by the
department applicable within the jurisdiction of a local agency if that local
agency, by January 1, 1993, has not adopted a water efficient landscape
ordinance or has not adopted certain findings that the adoption of the
ordinance is unnecessary.
This bill would specify that the provision making the model ordinance
applicable to a local agency on and after January 1, 1993, does not apply
to chartered cities. The bill would require the department, to the extent
funds are appropriated, not later than January 1, 2009, by regulation, to
update the model ordinance in accordance with specified requirements.
The bill would require the department to prepare and submit to the
Legislature a prescribed report before the adoption of the updated model
ordinance. The bill would require a local agency, not later than January 1,
2010, to adopt the updated model ordinance or other water efficient
92
landscape ordinance that is at least as effective in conserving water as the
updated model ordinance. The bill would make the updated model
ordinance applicable within the jurisdiction of a local agency, including a
chartered city, if, by January 1, 2010, the local agency has not adopted its
own water efficient landscape ordinance or the updated model ordinance.
The bill would require each local agency, not later than January 31, 2010,
to notify the department as to whether the local agency is subject to the
department’s updated model ordinance and, if not, to submit to the
department a copy of the water efficient landscape ordinance adopted by
the local agency, among other documents. The bill would require the
department, to the extent funds are appropriated, not later than January 31,
2011, to prepare and submit a report to the Legislature relating to the
status of water efficient landscape ordinances adopted by local agencies.
By imposing requirements on local agencies in connection with the
adoption of water efficient landscape ordinances, the bill would impose a
state-mandated local program.
(3) Existing law requires the State Energy Resources Conservation and
Development Commission (Energy Commission), after one or more public
hearings, to take specified action to reduce the wasteful, uneconomic,
inefficient, or unnecessary consumption of energy. Existing law requires
the Energy Commission, by January 1, 2004, to amend specified
regulations to require that residential clothes washers manufactured on or
after January 1, 2007, be at least as water efficient as commercial clothes
washers, and to take certain other related action.
This bill would require the Energy Commission, in consultation with the
department, to adopt, to the extent funds are available, by regulation
performance standards and labeling requirements for landscape irrigation
equipment, including irrigation controllers, moisture sensors, emission
devices, and valves to reduce the wasteful, uneconomic, inefficient, or
unnecessary consumption of energy or water. The bill would require the
Energy Commission to adopt those requirements for landscape irrigation
controllers and moisture sensors by January 1, 2010, and, on and after
January 1, 2012, would prohibit the sale or installation of an irrigation
controller or moisture sensor for landscape use unless the controller or
sensor meets those adopted requirements. The bill would require the
Energy Commission, on or before January 1, 2010, to prepare and submit
to the Legislature a report that sets forth a proposed schedule for adopting
performance standards and labeling requirements for emission devices and
valves.
(4) Existing law generally requires an urban water supplier to install
water meters on all municipal and industrial service connections located
within its service area on or before January 1, 2025.
This bill would require a water purveyor as defined, to require as a
condition of new retail water service on and after January 1, 2008, the
installation of separate water meters to measure the volume of water used
exclusively for landscape purposes. The bill would make this requirement
applicable to specified service connections.
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(5) The California Constitution requires the state to reimburse local
agencies and school districts for certain costs mandated by the state.
Statutory provisions establish procedures for making that reimbursement.
This bill would provide that, if the Commission on State Mandates
determines that the bill contains costs mandated by the state,
reimbursement for those costs shall be made pursuant to these statutory
provisions.
The people of the State of California do enact as follows:
SECTION 1.Section 1353.8 is added to the Civil Code, to read:
1353.8.The architectural guidelines of a common interest development
shall not prohibit or include conditions that have the effect of prohibiting
the use of low water-using plants as a group.
SEC. 2.Article 10.8 (commencing with Section 65591) of Chapter 3 of
Division 1 of Title 7 of the Government Code is repealed.
SEC. 3.Article 10.8 (commencing with Section 65591) is added to
Chapter 3 of Division 1 of Title 7 of the Government Code, to read:
Article 10.8.Water Conservation in Landscaping
65591.This article shall be known and may be cited as the Water
Conservation in Landscaping Act.
65592.Unless the context requires otherwise, the following definitions
govern the construction of this article:
(a) “Department” means the Department of Water Resources.
(b) “Local agency” means any city, county, or city and county,
including a charter city or charter county.
(c) “Water efficient landscape ordinance” means an ordinance or
resolution adopted by a local agency, or prepared by the department, to
address the efficient use of water in landscaping.
65593.The Legislature finds and declares all of the following:
(a) The waters of the state are of limited supply and are subject to ever
increasing demands.
(b) The continuation of California’s economic prosperity is dependent
on adequate supplies of water being available for future uses.
(c) It is the policy of the state to promote the conservation and efficient
use of water and to prevent the waste of this valuable resource.
(d) Landscapes are essential to the quality of life in California by
providing areas for active and passive recreation and as an enhancement to
the environment by cleaning air and water, preventing erosion, offering
fire protection, and replacing ecosystems lost to development.
(e) Landscape design, installation, maintenance, and management can
and should be water efficient.
(f) Section 2 of Article X of the California Constitution specifies that
the right to use water is limited to the amount reasonably required for the
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beneficial use to be served and the right does not and shall not extend to
waste or unreasonable use or unreasonable method of use.
(g) (1) The Legislature, pursuant to Chapter 682 of the Statutes of
2004, requested the California Urban Water Conservation Council to
convene a stakeholders work group to develop recommendations for
improving the efficiency of water use in urban irrigated landscapes.
(2) The work group report includes a recommendation to update the
model water efficient landscape ordinance adopted by the department
pursuant to Chapter 1145 of the Statutes of 1990.
(3) It is the intent of the Legislature that the department promote the use
of this updated model ordinance.
(h) Notwithstanding Article 13 (commencing with Section 65700), this
article addresses a matter that is of statewide concern and is not a
municipal affair as that term is used in Section 5 of Article XI of the
California Constitution. Accordingly, it is the intent of the Legislature that
this article, except as provided in Section 65594, apply to all cities and
counties, including charter cities and charter counties.
65594.(a) Except as provided in Section 65595, if by January 1, 1993,
a local agency did not adopt a water efficient landscape ordinance and did
not adopt findings based on climatic, geological, or topographical
conditions, or water availability that state that a water efficient landscape
ordinance is unnecessary, the model water efficient landscape ordinance
adopted by the department pursuant to Chapter 1145 of the Statutes of
1990 shall apply within the jurisdiction of the local agency as of that date,
shall be enforced by the local agency, and shall have the same force and
effect as if adopted by the local agency.
(b) Notwithstanding subdivision (b) of Section 65592, subdivision (a)
does not apply to chartered cities.
(c) This section shall apply only until the department updates the model
ordinance.
65595.(a) (1) To the extent funds are appropriated, not later than
January 1, 2009, by regulation, the department shall update the model
water efficient landscape ordinance adopted pursuant to Chapter 1145 of
the Statutes of 1990, after holding one or more public hearings. The
updated model ordinance shall be based on the recommendations set forth
in the report prepared pursuant to Chapter 682 of the Statutes of 2004 and
shall meet the requirements of Section 65596.
(2) Before the adoption of the updated model ordinance pursuant to
paragraph (1), the department shall prepare and submit to the Legislature a
report relating to both of the following:
(A) The extent to which local agencies have complied with the model
water efficient landscape ordinance adopted pursuant to Chapter 1145 of
the Statutes of 1990.
(B) The department’s recommendations regarding the landscape water
budget component of the updated model ordinance described in
subdivision (b) of Section 65596.
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(b) Not later than January 31, 2009, the department shall distribute the
updated model ordinance adopted pursuant to subdivision (a) to all local
agencies and other interested parties.
(c) On or before January 1, 2010, a local agency shall adopt one of the
following:
(1) A water efficient landscape ordinance that is, based on evidence in
the record, at least as effective in conserving water as the updated model
ordinance adopted by the department pursuant to subdivision (a).
(2) The updated model ordinance described in paragraph (1).
(d) If the local agency has not adopted, on or before January 1, 2010, a
water efficient landscape ordinance pursuant to subdivision (c), the
updated model ordinance adopted by the department pursuant to
subdivision (a) shall apply within the jurisdiction of the local agency as of
that date, shall be enforced by the local agency, and shall have the same
force and effect as if adopted by the local agency.
(e) Nothing in this article shall be construed to require the local
agency’s water efficient landscape ordinance to duplicate, or to conflict
with, a water efficiency program or measure implemented by a public
water system, as defined in Section 116275 of the Health and Safety Code,
within the jurisdictional boundaries of the local agency.
65596.The updated model ordinance adopted pursuant to Section
65595 shall do all the following in order to reduce water use:
(a) Include provisions for water conservation and the appropriate use
and groupings of plants that are well-adapted to particular sites and to
particular climatic, soil, or topographic conditions. The model ordinance
shall not prohibit or require specific plant species, but it may include
conditions for the use of plant species or encourage water conserving
plants. However, the model ordinance shall not include conditions that
have the effect of prohibiting or requiring specific plant species.
(b) Include a landscape water budget component that establishes the
maximum amount of water to be applied through the irrigation system,
based on climate, landscape size, irrigation efficiency, and plant needs.
(c) Promote the benefits of consistent local ordinances in neighboring
areas.
(d) Encourage the capture and retention of stormwater onsite to
improve water use efficiency or water quality.
(e) Include provisions for the use of automatic irrigation systems and
irrigation schedules based on climatic conditions, specific terrains and soil
types, and other environmental conditions. The model ordinance shall
include references to local, state, and federal laws and regulations
regarding standards for water-conserving irrigation equipment. The model
ordinance may include climate information for irrigation scheduling based
on the California Irrigation Management Information System.
(f) Include provisions for onsite soil assessment and soil management
plans that include grading and drainage to promote healthy plant growth
and to prevent excessive erosion and runoff, and the use of mulches in
shrub areas, garden beds, and landscaped areas where appropriate.
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(g) Promote the use of recycled water consistent with Article 4
(commencing with Section 13520) of Chapter 7 of Division 7 of the Water
Code.
(h) Seek to educate water users on the efficient use of water and the
benefits of doing so.
(i) Address regional differences, including fire prevention needs.
(j) Exempt landscaping that is part of a registered historical site.
(k) Encourage the use of economic incentives to promote the efficient
use of water.
(l) Include provisions for landscape maintenance practices that foster
long-term landscape water conservation. Landscape maintenance practices
may include, but are not limited to, performing routine irrigation system
repair and adjustments, conducting water audits, and prescribing the
amount of water applied per landscaped acre.
(m) Include provisions to minimize landscape irrigation overspray and
runoff.
65597.Not later than January 31, 2010, each local agency shall notify
the department as to whether the local agency is subject to the
department’s updated model ordinance adopted pursuant to Section 65595,
and if not, shall submit to the department a copy of the water efficient
landscape ordinance adopted by the local agency, and a copy of the local
agency’s findings and evidence in the record that its water efficient
landscape ordinance is at least as effective in conserving water as the
department’s updated model ordinance. Not later than January 31, 2011,
the department shall, to the extent funds are appropriated, prepare and
submit a report to the Legislature summarizing the status of water efficient
landscape ordinances adopted by local agencies.
65598.Any model ordinance adopted pursuant to this article shall
exempt cemeteries from all provisions of the ordinance except those set
forth in subdivisions (h), (k), and (l) of Section 65596. In adopting
language specific to cemeteries, the department shall recognize the special
landscape management needs of cemeteries.
65599.Any actions or proceedings to attach, review, set aside, void, or
annul the act, decision, or findings of a local agency on the ground of
noncompliance with this article shall be brought pursuant to Section 1085
of the Code of Civil Procedure.
SEC. 4.Section 25401.9 is added to the Public Resources Code, to
read:
25401.9.(a) To the extent that funds are available, the commission, in
consultation with the Department of Water Resources, shall adopt by
regulation, after holding one or more public hearings, performance
standards and labeling requirements for landscape irrigation equipment,
including, but not limited to, irrigation controllers, moisture sensors,
emission devices, and valves, for the purpose of reducing the wasteful,
uneconomic, inefficient, or unnecessary consumption of energy or water.
(b) For the purposes of complying with subdivision (a), the commission
shall do all of the following:
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(1) Adopt performance standards and labeling requirements for
landscape irrigation controllers and moisture sensors on or before January
1, 2010.
(2) Consider the Irrigation Association’s Smart Water Application
Technology Program testing protocols when adopting performance
standards for landscape irrigation equipment, including, but not limited to,
irrigation controllers, moisture sensors, emission devices, and valves.
(3) Prepare and submit a report to the Legislature, on or before January
1, 2010, that sets forth on a proposed schedule for adopting performance
standards and labeling requirements for emission devices and valves.
(c) On and after January 1, 2012, an irrigation controller or moisture
sensor for landscape irrigation uses may not be sold or installed in the state
unless the controller or sensor meets the performance standards and
labeling requirements established pursuant to this section.
SEC. 5.Article 4.5 (commencing with Section 535) is added to
Chapter 8 of Division 1 of the Water Code, to read:
Article 4.5. Irrigated Landscape
535.(a) A water purveyor shall require as a condition of new retail
water service on and after January 1, 2008, the installation of separate
water meters to measure the volume of water used exclusively for
landscape purposes.
(b) Subdivision (a) does not apply to either of the following:
(1) Single-family residential connections.
(2) Connections used to supply water for the commercial production of
agricultural crops or livestock.
(c) Subdivision (a) applies only to a service connection for which both
of the following apply:
(1) The connection serves property with more than 5,000 square feet of
irrigated landscape.
(2) The connection is supplied by a water purveyor that serves 15 or
more service connections.
(d) For the purposes of this section, “new retail water service” means
the installation of a new water meter where water service has not been
previously provided, and does not include applications for new water
service submitted before January 1, 2007.
SEC. 6.If the Commission on State Mandates determines that this act
contains costs mandated by the state, reimbursement to local agencies and
school districts for those costs shall be made pursuant to Part 7
(commencing with Section 17500) of Division 4 of Title 2 of the
Government Code.
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