Davis City Zoning Code
ARTICLE 40
42 WATER EFFICIENT LANDSCAPING
§ 40.42.010 Purpose.
The purpose of the landscaping standards contained in this article is to comply with the Water Conservation in Landscaping Act of 2006, Government Code Sections 65591 et seq. and to establish standards and procedures that promote the design, installation and management of water efficient landscaping. These standards may be reviewed and updated, as required.
(Ord. 2369 § 2, 2010)
§ 40.42.020 Applicability.
The provisions of this article shall apply to all of the following landscape projects within the City of Davis, except as otherwise noted:
Non-Residential Projects and Public Agency Projects. New construction and rehabilitated landscapes for public agency projects and private development projects with a landscape area equal to or greater than two thousand five hundred square feet requiring a building or landscape permit, plan check or design review.
Residential Projects With Developer-Installed Landscaping. New construction and rehabilitated landscapes which are developer-installed in single-family and multifamily projects with a landscape area equal to or greater than two thousand five hundred square feet per lot requiring a building or landscape permit, plan check, or design review.
Residential Projects With Homeowner-Provided Landscaping. New construction landscapes which are homeowner-provided and/or homeowner-hired in single-family and multifamily residential projects with a total project landscape area equal to or greater than five thousand square feet requiring a building or landscape permit, plan check or design review.
Existing Landscaping. Requirements for existing landscapes installed prior to the effective date of the ordinance codified in this article and not rehabilitated are limited to Section 40.42.040.
The provisions of this article do not apply to:
Historical Sites. Registered local, state or federal historical sites;
Restoration Projects. Ecological restoration projects that do not require a permanent irrigation system;
Reclamation Projects. Mined-land reclamation projects that do not require a permanent irrigation system; or
Plant Collections. Plant collections, as part of botanical gardens and arboretums open to the public.
(Ord. 2369 § 2, 2010)
§ 40.42.030 Definitions.
The terms used in this article have the meaning set forth below:
The portion of water supplied by the irrigation system to the landscape.
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.
A safety device used to prevent pollution or contamination of the water supply due to the reverse flow of water from the irrigation system.
The document required under Section 40.42.120.
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.
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.
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.
Community apartment projects, condominium projects, planned developments, and stock cooperatives per Civil Code Section 1351.
The number that converts acre-inches per acre per year to gallons per square foot per year.
Landscape area on a property installed by the developer of the property or licensed contractor hired by the developer of the property. A developer, for the purposes of this article, includes anyone or any group not defined as a homeowner by this article.
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.
A project where the site is intentionally altered to establish a defined, indigenous, historic ecosystem.
The portion of total precipitation which becomes available for plant growth.
A drip irrigation emission device that delivers water slowly from the system to the soil.
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.
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.
The total water used for the landscape as described in Section 40.42.070(a).
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.
The quantity of water evaporated from adjacent soil and other surfaces and transpired by plants during a specified time.
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.
Any durable material (pervious and non-pervious).
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 article, is a person who occupies the dwelling he or she owns. This excludes speculative homes, which are not owner-occupied dwellings.
A portion of the landscaped area having plants with similar water needs. A hydrozone may be irrigated or non-irrigated.
The rate of water entry into the soil expressed as a depth of water per unit of time (e.g., inches per hour).
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.
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 tuneup, system test with distribution uniformity or emission uniformity, reporting overspray or runoff that causes overland flow, and preparation of an irrigation schedule.
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 article is 0.71. Greater irrigation efficiency can be expected from well designed and maintained systems.
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.
An analysis of water use data based on meter readings and billing data.
A person who holds a license to practice landscape architecture in the State of California Business and Professions Code Section 5615.
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 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).
A person licensed by the State of California to construct, maintain, repair, install, or subcontract the development of landscape systems.
The documents required under Section 40.42.060.
The total area of landscape in a project as defined in "landscape area" for the purposes of this article, meeting requirements under Section 40.42.020.
The water delivery pipeline that supplies water to the emitters or sprinklers from the valve.
Any entity, including a public agency, city, county, or private water company that provides retail water service.
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.
The pressurized pipeline that delivers water from the water source to the valve or outlet.
The upper limit of annual applied water for the established landscaped area as specified in Section 40.42.070. 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.
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.
Any surface mining operation with a reclamation plan approved in accordance with the Surface Mining and Reclamation Act of 1975.
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.
For the purposes of this article, a new building with a landscape or other new landscape, such as a park, playground, or greenbelt without an associated building.
The pressure at which the parts of an irrigation system are designed by the manufacturer to operate.
Systems that deliver water through the air (e.g., spray heads and rotors).
The irrigation water which is delivered beyond the target area.
An authorizing document issued by local agencies for new construction or rehabilitated landscapes.
Any surface or material that allows the passage of water through the material and into the underlying soil.
A factor, when multiplied by ETo, estimates the amount of water needed by plants. For purposes of this article, the plant factor range for low water 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 article are derived from the Department of Water Resources 2000 publication "Water Use Classification of Landscape Species."
The rate of application of water measured in inches per hour.
The individual or entity submitting a landscape documentation package, to request a permit, plan check, or design review from the City of Davis. A project applicant may be the property owner or designee.
A component which automatically suspends an irrigation event when it rains.
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.
Areas dedicated to active play such as parks, sports fields, and golf courses where turf provides a playing surface.
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.
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, 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.
Any re-landscaping project that requires a permit, plan check, or design review, meets the requirements of Section 40.42.020, and the modified landscape area is equal to or greater than two thousand five hundred square feet and is fifty percent or more of the total landscape area.
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.
A device that measures the amount of water in the soil. The device may also suspend or initiate an irrigation event.
The classification of soil based on its percentage of sand, silt, and clay.
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.
A device which delivers water through a nozzle.
The pipeline or municipal water supply pressure when water is not flowing.
An area served by one valve or by a set of valves that operate simultaneously.
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.
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.
A device used to control the flow of water in the irrigation system.
A plant species identified as having a low plant factor.
A design element where open water performs an aesthetic or recreational function. Water features include ponds, lakes, waterfalls, fountains, artificial streams, spas, and 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.
The time of day irrigation is allowed.
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.
(Ord. 2369 § 2, 2010)
§ 40.42.040 Provisions for existing landscapes installed prior to effective date.
This section shall apply to all existing landscapes that were installed prior to the effective date of the ordinance codified in this article. However, existing landscapes installed between January 1, 2010 and the effective date of said ordinance are subject to the requirements of the Water Conservation in Landscaping Act of 2006.
All existing landscapes installed prior to the effective date of the ordinance codified in this article and over one acre in size that have a water meter are subject to programs administered by the City of Davis that may include, but are not 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 in accordance with Section 40.42.070 and using the following equation:
MAWA = (0.8)(ETo)(LA)(0.62) |
Where: |
0.8 = ET adjustment factor (ETAF) for existing non-rehabilitated landscapes |
ETo = Reference evapotranspiration for City of Davis (annual ETo in inches per year) |
LA = Landscape area (square feet) |
0.62 = Conversion factor |
All existing landscapes that do not have a meter are subject to programs administered by the City of Davis that may include, but are not limited to, irrigation surveys and irrigation audits to evaluate water use and provide recommendations as necessary in order to prevent water waste.
All landscape irrigation audits shall be conducted by a certified landscape irrigation auditor.
(Ord. 2369 § 2, 2010)
§ 40.42.050 Provisions for new construction or rehabilitated landscapes.
Prior to construction or issuance of permits, the project applicant for a new construction or rehabilitated landscape project, as described in Section 40.42.020, shall submit a complete landscape documentation package to the department of community development and sustainability for review and approval.
Upon approval of the landscape documentation package by the department of community development and sustainability, the project applicant shall:
(Ord. 2369 § 2, 2010)
§ 40.42.060 Landscape documentation package requirements.
The landscape documentation package shall include the following six elements and as detailed in the subsequent sections:
Project Information. The project applicant shall provide the following minimum required project information:
Date,
Project applicant,
Project address (if available, parcel and/or lot number(s)),
Total landscape area (square feet),
Project type (e.g., new, rehabilitated, public, private, cemetery, homeowner-installed),
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,
Checklist of all documents in landscape documentation package,
Project contacts to include contact information for the project applicant and property owner,
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.";
Water efficient landscape worksheet;
Soil management report;
Landscape design plan;
Irrigation design plan; and
Grading design plan.
Project applicant shall provide the required information on state-recommended forms or city-equivalent forms if available. All required reports and plans shall be provided in a form determined acceptable by the director of community development and sustainability and shall be subject to city review and approval.
(Ord. 2369 § 2, 2010)
§ 40.42.070 Water efficient landscape worksheet.
Landscape worksheet components. In order to determine the water budget and water needs for project landscaping, the project applicant shall complete the city's water efficient landscape worksheet which contains two sections:
Water budget calculation requirements. Water budget calculations shall adhere to the following requirements:
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.
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.
All special landscape areas shall be identified and their water use calculated as described below.
ETAF for special landscape areas shall not exceed 1.0.
For the purposes of determining these water calculations, average irrigation efficiency is assumed to be 0.71.
For the calculation of the maximum applied water allowance and estimated total water use, a project applicant shall use the following ETo values, or as may be updated, for the City of Davis:
Reference Evapotranspiration (ETo) Table for City of Davis | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual ETo |
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 |
Maximum applied water allowance (MAWA). The maximum applied water allowance shall be calculated using the equation:
MAWA = (ETo) (0.62) [(0.7 x LA) + (0.3 x SLA)] |
Estimated total water use (ETWU). 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 maximum applied water allowance.
 |
Where: |
ETWU = Estimated total water use per year (gallons) |
ETo = Reference evapotranspiration for City of Davis (annual ETo in inches per year) |
PF = Plant factor from WUCOLS |
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) |
(Ord. 2369 § 2, 2010)
§ 40.42.080 Soil management report.
Soil report requirements. In order to reduce runoff and encourage healthy plant growth, a soil management report shall be completed by the project applicant, or designee, and submitted, as follows:
Project applicant shall submit soil samples to a qualified laboratory for analysis and recommendations to be included in the soil report.
Soil sampling shall be conducted in accordance with laboratory protocol, including protocols regarding adequate sampling depth for the intended plants.
The project applicant, or designee, shall comply with one of the following:
If significant mass grading is not planned, the soil analysis report shall be submitted to the department of community development and sustainability for review as part of the landscape documentation package; or
If significant mass grading is planned, the soil analysis report shall be submitted to the department of community development and sustainability for review as part of the certificate of completion.
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.
The project applicant, or designee, shall submit documentation verifying implementation of soil analysis report recommendations to the department of community development and sustainability with the certificate of completion.
(Ord. 2369 § 2, 2010)
§ 40.42.090 Landscape design plan.
Landscape design criteria. 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.
Plant Material.
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:
Protection and preservation of native species and natural vegetation;
Selection of water-conserving plant and turf species;
Selection of plants based on disease and pest resistance;
Selection of trees based on the city's master tree list; and
Selection of plants from city, local, and regional landscape program plant lists.
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 40.42.100(a)(2)(D).
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:
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;
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
Consider the solar orientation for plant placement to maximize summer shade and winter solar gain.
Turf is not allowed on slopes greater than twenty-five percent where the toe of the slope is adjacent to an impermeable hardscape and where twenty-five percent means one foot of vertical elevation change for every four feet of horizontal length (rise divided by run x 100 = slope percent).
The use of invasive and/or noxious plant species is strongly discouraged.
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.
Water Features.
Recirculating water systems shall be used for water features.
Where available, recycled water shall be used as a source for decorative water features.
Surface area of a water feature shall be included in the high water use hydrozone area of the water budget calculation.
Pool and spa covers are highly recommended.
Mulch and Amendments.
A minimum two inch 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.
Stabilizing mulching products shall be used on slopes.
The mulching portion of the seed/mulch slurry in hydro-seeded applications shall meet the mulching requirement.
Soil amendments shall be incorporated according to recommendations of the soil report and what is appropriate for the plants selected.
Landscape plan requirements. The landscape design plan, at a minimum, shall:
Delineate and label each hydrozone by number, letter, or other method;
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;
Identify recreational areas;
Identify areas permanently and solely dedicated to edible plants;
Identify areas irrigated with recycled water;
Identify type of mulch and application depth;
Identify soil amendments, type, and quantity;
Identify type and surface area of water features;
Identify hardscapes (pervious and non-pervious);
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:
Infiltration beds, swales, and basins that allow water to collect and soak into the ground,
Constructed wetlands and retention ponds that retain water, handle excess flow, and filter pollutants, and
Pervious or porous surfaces (e.g., permeable pavers or blocks, pervious or porous concrete, etc.) that minimize runoff;
Identify any applicable rain harvesting or catchment technologies (e.g., rain gardens, cisterns, etc.);
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
Bear the signature of a licensed landscape architect, licensed landscape contractor, or any other person authorized to design a landscape.
(Ord. 2369 § 2, 2010)
§ 40.42.100 Irrigation design plan.
Irrigation design criteria. 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.
Irrigation System Requirements.
Dedicated landscape water meters are highly recommended on landscape areas smaller than five thousand square feet to facilitate water management.
Automatic irrigation controllers utilizing either evapotranspiration or soil moisture sensor data shall be required for irrigation scheduling in all irrigation systems.
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.
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.
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.
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.
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.
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.
High flow sensors that detect and report high flow conditions created by system damage or malfunction are recommended.
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.
Relevant information from the soil management plan, such as soil type and infiltration rate, shall be utilized when designing irrigation systems.
The design of the irrigation system shall conform to the hydrozones of the landscape design plan.
The irrigation system must be designed and installed to meet, at a minimum, the irrigation efficiency criteria as described in Section 40.42.160 regarding the estimated total water use calculation.
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.
In mulched planting areas, the use of low volume irrigation is required to maximize water infiltration into the root zone.
Sprinkler heads and other emission devices shall have matched precipitation rates, unless otherwise directed by the manufacturer's recommendations.
Head-to-head coverage is recommended. However, sprinkler spacing shall be designed to achieve the highest possible distribution uniformity using the manufacturer's recommendations.
Swing joints or other riser-protection components are required on all risers subject to damage that are adjacent to high traffic areas.
Check valves or anti-drain valves are required for all irrigation systems.
Narrow or irregularly shaped areas, including turf, less than eight feet in width in any direction shall be irrigated with subsurface irrigation or low volume irrigation system.
Overhead irrigation shall not be permitted within twenty-four 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:
The landscape area is adjacent to permeable surfacing and no runoff occurs; or
The adjacent non-permeable surfaces are designed and constructed to drain entirely to landscaping; or
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. Prevention of overspray and runoff must be confirmed during the irrigation audit.
Slopes greater than twenty-five percent 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.
Hydrozone.
Each valve shall irrigate a hydrozone with similar site, slope, sun exposure, soil conditions, and plant materials with similar water use.
Sprinkler heads and other emission devices shall be selected based on what is appropriate for the plant type within that hydrozone.
Where feasible, trees shall be placed on separate valves from shrubs, groundcovers, and turf.
Individual hydrozones that mix plants of moderate and low water use, or moderate and high water use, may be allowed if:
Individual hydrozones that mix high and low water use plants shall not be permitted.
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 on the city-provided form. This table can also assist with the irrigation audit and programming the controller.
Irrigation plan requirements. The irrigation design plan, at a minimum, shall contain:
Location and size of separate water meters for landscape;
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;
Static water pressure at the point of connection to the public water supply;
Flow rate (gallons per minute), application rate (inches per hour), and design operating pressure (pressure per square inch) for each station;
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
The signature of a licensed landscape architect, certified irrigation designer, licensed landscape contractor, or any other person authorized to design an irrigation system.
(Ord. 2369 § 2, 2010)
§ 40.42.110 Grading design plan.
Grading plan requirements. 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.
To prevent excessive erosion and runoff, it is highly recommended that project applicants:
Grade so that all irrigation and normal rainfall remains within property lines and does not drain on to non-permeable hardscapes;
Avoid disruption of natural drainage patterns and undisturbed soil; and
Avoid soil compaction in landscape areas; and
Decompact and break up compacted soil in landscape areas.
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.
(Ord. 2369 § 2, 2010)
§ 40.42.120 Certificate of completion.
Certificate of completion elements. The certificate of completion shall include the following six elements in a form determined acceptable to the director of community development and sustainability:
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.
Where there have been significant changes made in the field during construction, these "as-built" or record drawings shall be included with the certification;
Soil analysis report, if not submitted with landscape documentation package, and documentation verifying implementation of soil report recommendations.
Certificate of completion submittal. Upon completion of the landscape project and prior to final of the permit or occupancy, the project applicant shall:
City review procedures. Upon submittal of the completed certificate of completion, the department of community development and sustainability shall:
Receive the signed certificate of completion from the project applicant;
Upon review of the certificate of completion, approve or deny the certificate of completion. If the certificate of completion is denied, the City of Davis shall not be obligated to issue an occupancy permit and shall provide information to the project applicant regarding reapplication, appeal, or other assistance.
(Ord. 2369 § 2, 2010)
§ 40.42.130 Irrigation scheduling.
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:
Irrigation scheduling shall be regulated by automatic irrigation controllers.
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.
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.
Each irrigation schedule shall consider for each station all of the following that apply:
Irrigation interval (days between irrigation);
Irrigation run times (hours or minutes per irrigation event to avoid runoff);
Number of cycle starts required for each irrigation event to avoid runoff;
Amount of applied water scheduled to be applied on a monthly basis;
Application rate setting;
Root depth setting;
Plant type setting;
Soil type;
Slope factor setting;
Shade factor setting; and
Irrigation uniformity or efficiency setting.
(Ord. 2369 § 2, 2010)
§ 40.42.140 Landscape and irrigation maintenance schedule.
Landscapes shall be maintained to ensure water use efficiency. A regular maintenance schedule shall be submitted with the certificate of completion.
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.
Repair of all irrigation equipment shall be done with the originally installed components or their equivalents.
A project applicant is encouraged to implement sustainable or environmentally-friendly practices for overall landscape maintenance.
(Ord. 2369 § 2, 2010)
§ 40.42.150 Irrigation audits.
All landscape irrigation audits shall be conducted by a certified landscape irrigation auditor.
For new construction and rehabilitated landscape projects installed after adoption of the ordinance codified in this article, as described in Section 40.42.020:
The project applicant shall submit an irrigation audit report with the certificate of completion to the City of Davis that may include, but is not limited to: inspection, system tune-up, system test with distribution uniformity, reporting overspray or runoff that causes overland flow, and preparation of an irrigation schedule.
The City of Davis will maintain a reference list of certified water service auditors. The list shall be provided to project applicants upon request.
The City of Davis may 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.
(Ord. 2369 § 2, 2010)
§ 40.42.160 Irrigation efficiency.
For the purposes of determining the water calculations, 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.
(Ord. 2369 § 2, 2010)
§ 40.42.170 Recycled water.
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 40.42.170(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.
All recycled water irrigation systems shall be designed and operated in accordance with all applicable local and state laws.
Landscapes using recycled water are considered special landscape areas. The ET adjustment factor for special landscape areas shall not exceed 1.0.
(Ord. 2369 § 2, 2010)
§ 40.42.180 Stormwater management.
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.
Projects shall comply with applicable city requirements for stormwater best management practices as detailed in the city's stormwater runoff ordinance or equivalent. Measures shall be incorporated and shown in the applicable plans subject to review and approval.
Rain gardens, cisterns, and other landscapes features and practices that increase rainwater capture and create opportunities for infiltration and/or on-site storage are recommended.
(Ord. 2369 § 2, 2010)
§ 40.42.190 Public education.
The City of Davis or the project developer shall provide information to owners of new, single-family residential homes regarding the design, installation, management, and maintenance of water efficient landscapes in a form determined acceptable to the city.
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 article.
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.
Information shall be provided about designing, installing, managing, and maintaining water efficient landscapes.
(Ord. 2369 § 2, 2010)
§ 40.42.200 Effective precipitation.
The city may consider effective precipitation (up to a maximum of twenty-five percent of annual precipitation) in tracking water use. The following equation may be used to calculate maximum applied water allowance where Eppt is the effective precipitation:
MAWA= (ETo - Eppt) (0.62) [(0.7 x LA) + (0.3 x SLA)]
(Ord. 2369 § 2, 2010)
§ 40.42.210 Fees.
The City of Davis may establish fees for necessary review and inspections related to the requirements of this article.
(Ord. 2369 § 2, 2010)
§ 40.42.220 Penalties.
Failure to comply with the requirements of this article may result in enforcement and penalties in accordance with Municipal Code Chapter 23.
(Ord. 2369 § 2, 2010)