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Hawthorne City Zoning Code

CHAPTER 17

89 WATER EFFICIENT LANDSCAPING

§ 17.89.010 Purpose.

The purpose of this chapter is to establish water efficient landscape regulations that are "at least as effective in conserving water as" the State Model Water Efficient Landscape Ordinance (Government Code Section 65591 et seq.) in the context of conditions in the city in order to ensure that landscapes are planned, designed, installed, maintained, and managed in a manner that uses water efficiently, encourages water conservation, and prevents water waste.
(Ord. 2140 § 11, 2017)

§ 17.89.020 Definitions.

For the purposes of this chapter and the Water Efficient Landscape Guidelines that implement this chapter, the following terms are defined:
"Applicant"
means the person submitting a landscape documentation package. Applicants can be the property owner or the owner's designee.
"Applied water"
means the portion of water supplied by the irrigation system to the landscape.
"Automatic irrigation controller"
means a timing device used to remotely control valves that operate an irrigation system. Automatic irrigation controllers are able to self-adjust and schedule irrigation events using either evapotranspiration (weather-based) or soil moisture data.
"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.
"Certificate of completion"
means the document required under Section 2.2 of the Water Efficient Landscape Guidelines.
"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 U.S. Environmental Protection Agency's WaterSense Irrigation Designer Certification Program and Irrigation Association's Certified Irrigation Designer Program.
"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 U.S. Environmental Protection Agency's WaterSense Irrigation Auditor Certification Program and Irrigation Association's Certified Landscape Irrigation Auditor Program.
"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.
"Common interest developments"
means community apartment projects, condominium projects, planned developments, and stock cooperatives per Civil Code Section 1351.
"Compost"
has the same meaning as in 14 CCR Section 17896.2(a)(4), which stated, as of the effective date of the ordinance codified in this section, that "compost" means the product resulting from the controlled biological decomposition of organic solid wastes that are source separated from the municipal solid waste stream, or which are separated at a centralized facility.
"Conversion factor (0.62)"
means the number that converts acre-inches per acre per year to gallons per square foot per year.
"Distribution uniformity"
means the measure of the uniformity of irrigation water over a defined area.
"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.
"Ecological restoration project"
means a project where the site is intentionally altered to establish a defined, indigenous, historic ecosystem.
"Effective precipitation (Eppt)"
or "usable rainfall" means the portion of total precipitation which becomes available for plant growth.
"Emitter"
means a drip irrigation emission device that delivers water slowly from the system to the soil. "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.
"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. Native habitat mitigation areas and trees may need three to five years for establishment.
"Estimated total water use (ETWU)"
means the total water used for the landscape as described in Section 2.1.B.2 of the Water Efficient Landscape Guidelines.
"ET adjustment factor (ETAF)"
means a factor of 0.55 for residential areas and 0.45 for nonresidential areas, 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. The ETAF for new and existing (non-rehabilitated) special landscape areas shall not exceed 1.0. The ETAF for existing non-rehabilitated landscapes is 0.8.
"Evapotranspiration rate"
means the quantity of water evaporated from adjacent soil and other surfaces and transpired by plants during a specified time.
"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.
"Flow sensor"
means an inline device installed at the supply point of the irrigation system that produces a repeatable signal proportional to flow rate. Flow sensors must be connected to an automatic irrigation controller, or flow monitor capable of receiving flow signals and operating master valves. This combination flow sensor/controller may also function as a landscape water meter or submeter.
"Friable"
means a soil condition that is easily crumbled or loosely compacted down to a minimum depth per planting material requirements, whereby the root structure of newly planted material will be allowed to spread unimpeded.
"Fuel Modification Plan Guideline"
means guidelines from a local fire authority to assist residents and businesses that are developing land or building structures in a fire hazard severity zone.
"Graywater"
means untreated wastewater that has not been contaminated by any toilet discharge, has not been affected by infectious, contaminated, or unhealthy bodily wastes, and does not present a threat from contamination by unhealthful processing, manufacturing, or operating wastes. "Graywater" includes, but is not limited to, wastewater from bathtubs, showers, bathroom washbasins, clothes washing machines, and laundry tubs, but does not include wastewater from kitchen sinks or dishwashers. Health and Safety Code Section 17922.12.
"Hardscapes"
means any durable material (pervious and non-pervious).
"Hydrozone"
means a portion of the landscaped area having plants with similar water needs and rooting depth. A hydrozone may be irrigated or non-irrigated.
"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).
"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. Lists of invasive plants are maintained at the California Invasive Plant Inventory and USDA invasive and noxious weeds database.
"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. The audit must be conducted in a manner consistent with the Irrigation Association's Landscape Irrigation Auditor Certification program or other U.S. Environmental Protection Agency "Water-Sense" labeled auditing program.
"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 irrigation efficiency for purposes of this ordinance are 0.75 for overhead spray devices and 0.81 for drip systems.
"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.
"Irrigation water use analysis"
means an analysis of water use data based on meter readings and billing data.
"Landscape architect"
means a person who holds a license to practice landscape architecture in the state of California Business and Professions Code, Section 5615.
"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 stone walks, other pervious or non-pervious hard-scapes, and other non-irrigated areas designated for non-development (e.g., open spaces and existing native vegetation).
"Landscape contractor"
means a person licensed by the state of California to construct, maintain, repair, install, or subcontract the development of landscape systems.
"Landscape documentation package"
means the documents required under Section 17.89.060.
"Landscape project"
means total area of landscape in a project as defined in "landscape area" for the purposes of this chapter, meeting requirements under Section 17.89.030.
"Landscape water meter"
means an inline device installed at the irrigation supply point that measures the flow of water into the irrigation system and is connected to a totalizer to record water use.
"Lateral line"
means the water delivery pipeline that supplies water to the emitters or sprinklers from the valve.
"Local agency"
means a city or county, including a charter city or charter county, that is responsible for adopting and implementing this chapter. The local agency is also responsible for the enforcement of this chapter, including, but not limited to, approval of a permit and plan check or design review of a project.
"Local water purveyor"
means any entity, including a public agency, city, county, or private water company that provides retail water service.
"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.
"Main line"
means the pressurized pipeline that delivers water from the water source to the valve or outlet.
"Master shut-off valve"
is an automatic valve installed at the irrigation supply point which controls water flow into the irrigation system. When this valve is closed water will not be supplied to the irrigation system. A master valve will greatly reduce any water loss due to a leaky station valve.
"Maximum applied water allowance (MAWA)"
means the upper limit of annual applied water for the established landscaped area as specified in Section 2.1.B.2 of the Water Efficient Landscape Guidelines. 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. MAWA = (ETo) (0.62) [(ETAF x LA) + ((1-ETAF) x SLA)].
"Median"
is an area between opposing lanes of traffic that may be unplanted or planted with trees, shrubs, perennials, and ornamental grasses.
"Microclimate"
means the climate of a small, specific area that may contrast with the climate of the overall land-scape area due to factors such as wind, sun exposure, plant density, or proximity to reflective surfaces.
"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.
"Mulch"
means any organic material such as leaves, bark, straw, compost, or inorganic mineral materials such as rocks, gravel, or 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.
"New construction"
means, for the purposes of this chapter, a new building with a landscape or other new land-scape, such as a park, playground, or greenbelt without an associated building.
"Nonresidential landscape"
means landscapes in commercial, institutional, industrial and public settings that may have areas designated for recreation or public assembly. It also includes portions of common areas of common interest developments with designated recreational areas.
"Operating pressure"
means the pressure at which the parts of an irrigation system are designed by the manufacturer to operate.
"Overhead sprinkler irrigation systems"
or "overhead spray irrigation systems" means systems that deliver water through the air (e.g., spray heads and rotors).
"Overspray"
means the irrigation water which is delivered beyond the target area.
"Parkway"
means the area between a sidewalk and the curb or traffic lane. It may be planted or unplanted, and with or without pedestrian egress.
"Permit"
means an authorizing document issued by the city for new construction or rehabilitated landscapes.
"Pervious"
means any surface or material that allows the passage of water through the material and into the underlying soil.
"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 chapter, the plant factor range for very low water use plants is 0 to 0.1, the plant factor range for low water use plants is 0.1 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 chapter are derived from the publication "Water Use Classification of Landscape Species." Plant factors may also be obtained from horticultural researchers from academic institutions or professional associations as approved by the California Department of Water Resources (DWR).
"Project applicant"
means the individual or entity submitting a landscape documentation package required under Section 17.89.060, to request a permit, plan check, or design review from the city. A project applicant may be the property owner or designee.
"Rain sensor" or "rain sensing shutoff device"
means a component which automatically suspends an irrigation event when it rains.
"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.
"Recreational area"
means areas, excluding private single-family residential areas, designated for active play, recreation or public assembly such as in parks, sports fields, picnic grounds, amphitheaters or golf course tees, fair-ways, roughs, surrounds and greens.
"Recycled water,"
"reclaimed water," or "treated sewage effluent water" means treated or recycled waste water of a quality suitable for nonpotable uses such as landscape irrigation and water features. This water is not intended for human consumption.
"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 Appendix B of the Water Efficient Landscape Guidelines, 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 allowances so that regional differences in climate can be accommodated.
"Regional water efficient landscape ordinance"
means a local ordinance adopted by two or more local agencies, water suppliers and other stakeholders for implementing a consistent set of landscape provisions throughout a geographical region. Regional ordinances are strongly encouraged to provide a consistent framework for the landscape Hawthorne and applicants to adhere to.
"Rehabilitated landscape"
means any re-landscaping project that requires a permit, plan check, or design review, meets the requirements of Section 17.89.030, and the modified landscape area is equal to or greater than two thousand five hundred square feet.
"Residential landscape"
means landscapes surrounding single or multifamily homes.
"Run-off"
means water which is not absorbed by the soil or landscape to which it is applied and flows from the landscape area. For example, run-off may result from water that is applied at too great a rate (application rate exceeds infiltration rate) or when there is a slope.
"Soil moisture sensing device"w 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.
"Soil texture"
means the classification of soil based on its percentage of sand, silt, and clay.
"Special landscape area (SLA)"
means an area of the landscape dedicated solely to edible plants, recreational areas, areas irrigated with recycled water, or water features using recycled water.
"Sprinkler head" or "spray head"
means a device which delivers water through a nozzle.
"Static water pressure"
means the pipeline or municipal water supply pressure when water is not flowing.
"Station"
means an area served by one valve or by a set of valves that operate simultaneously.
"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.
"Submeter"
means a metering device to measure water applied to the landscape that is installed after the primary utility water meter.
"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.
"Valve"
means a device used to control the flow of water in the irrigation system.
"Water conserving plant species"
means a plant species identified as having a very low or low plant factor.
"Water Efficient Landscape Guidelines" or "Guidelines"
refers to the Water Efficient Landscape Guidelines, as approved by and available at the city, which describes procedures, calculations, and requirements for landscape projects subject to the Guidelines.
"Water Efficient Landscape Ordinance"
means Chapter 17.89 of the Hawthorne Municipal Code.
"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 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.
"Watering window"
means the time of day irrigation is allowed.
"WUCOLS"
means the Water Use Classification of Landscape Species published by the University of California Cooperative Extension and the Department of Water Resources 2014.
(Ord. 2140 § 11, 2017; Ord. 2226 § 7, 2021)

§ 17.89.030 Applicability.

A. 
The following landscape projects in this chapter shall comply with 23 CCR, Division 2, Chapter 2.7, Sections 492.6(a)(3)(B), (C), (D), and (G) of the Model Water Efficient Landscaping Ordinance (MWELO), including sections related to use of compost and mulch:
1. 
New construction projects (residential, public, institutional, or commercial), including anyone requiring a building or planning permit, with an aggregate landscape area equal to or greater than five hundred square feet requiring a building or landscape permit, plan check or design review;
2. 
Rehabilitated landscape projects with an aggregate landscape area equal to or greater than two thousand five hundred square feet requiring a building or landscape permit, plan check, or design review;
3. 
Existing landscapes limited to Section 3.1 of the Water Efficient Landscape Guidelines; and
4. 
Cemeteries. Recognizing the special landscape management needs of cemeteries, new and rehabilitated cemeteries are limited to Sections 2.1.B.2, 2.2.A.4, and 2.2.A.5 of the Water Efficient Landscape Guidelines; and existing cemeteries are limited to Section 3.1 of the Water Efficient Landscape Guidelines.
B. 
Any project with an aggregate landscape area of two thousand five hundred square feet or less may comply with the performance requirements of this chapter or conform to the prescriptive measures contained in Appendix E of the Water Efficient Landscape Guidelines.
For projects using treated or untreated graywater or rainwater captured on site, any lot or parcel within the project that has less than two thousand five hundred square feet of landscape and meets the lot or parcel's landscape water requirement (estimated total water use) entirely with treated or untreated graywater or through stored rainwater captured on site is subject only to Section B.5 of Appendix E of the Water Efficient Landscape Guidelines.
C. 
The following compost and mulch use requirements that are part of the MWELO are now also included as requirements of this section. Other requirements of the MWELO are in effect and can be found in 23 CCR, Division 2, Chapter 2.7.
D. 
Property owners or their building or landscape designers that meet the threshold for MWELO compliance outlined above shall:
1. 
Comply with 23 CCR, Division 2, Chapter 2.7, Sections 492.6(G) and (D), (C), (a)(3)(B) of the MWELO, which requires the submittal of a landscape design plan with a soil preparation, mulch, and amendments section to include the following:
a. 
For landscape installations, compost at a rate of a minimum of four cubic yards per one thousand square feet of permeable area shall be incorporated to a depth of six inches into the soil. Soils with greater than six percent organic matter in the top six inches of soil are exempt from adding compost and tilling.
b. 
For landscape installations, a minimum three-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. To provide habitat for beneficial insects and other wildlife up to five percent of the landscape area may be left without mulch. Designated insect habitat must be included in the landscape design plan as such.
c. 
Organic mulch materials made from recycled or post-consumer materials shall take precedence over inorganic materials or virgin forest products unless the recycled post-consumer organic products are not locally available. Organic mulches are not required where prohibited by local fuel modification plan guidelines or other applicable local ordinances.
2. 
The MWELO compliance items listed in this section are not an inclusive list of MWELO requirements; therefore, property owners or their building or landscape designers that meet the threshold for MWELO compliance outlined shall consult the full MWELO for all requirements.
E. 
If, after the adoption of the ordinance codified in this section, the California Department of Water Resources, or its successor agency, amends 23 CCR, Division 2, Chapter 2.7, Sections 492.6(a)(3)(B), (C), (D), and (G) of the MWWELO September 15, 2015 requirements in a manner that requires City to incorporate the requirements of an updated MWELO in a local ordinance, and the amended requirements include provisions more stringent than those required in this section, the revised requirements of 23 CCR, Division 2, Chapter 2.7 shall be enforced.
(Ord. 2140 § 11, 2017; Ord. 2226 § 7, 2021)

§ 17.89.040 Exemptions.

This chapter does not apply to:
A. 
Registered local, state or federal historical sites;
B. 
Ecological restoration projects that do not require a permanent irrigation system;
C. 
Mined-land reclamation projects that do not require a permanent irrigation system; or
D. 
Existing plant collections, as part of botanical gardens and arboretums open to the public.
(Ord. 2140 § 11, 2017)

§ 17.89.050 Water Efficient Landscape Guidelines.

The Water Efficient Landscape Guidelines as adopted by resolution of the city council, as they may be amended from time to time, is hereby incorporated into this chapter by reference.
(Ord. 2140 § 11, 2017)

§ 17.89.060 Procedures.

A. 
Landscape Design and Review. Prior to installation and construction, the applicant shall submit a complete landscape documentation package that complies with the provisions of this chapter and the Water Efficient Landscape Guidelines to the planning department for approval. The landscape documentation package shall include the following elements, as detailed in the Water Efficient Landscape Guidelines:
1. 
Project information including all of the following:
a. 
Date,
b. 
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 applicant and property owner,
i. 
Applicant signature and date with statement, "I agree to comply with the requirements of the Water Efficient Landscape Guidelines and submit a complete Landscape Documentation Package";
2. 
Water efficient landscape worksheet including calculations for the maximum applied water allowance (MAWA) and estimated total water use (ETWU) in compliance with this chapter and as contained in Appendix C of the Water Efficient Landscape Guidelines;
3. 
Soil management report;
4. 
Landscape design plan;
5. 
Irrigation design plan;
6. 
Grading design plan; and
7. 
A certificate of landscape design (Appendix A of the Water Efficient Landscape Guidelines) on the land-scape plans verifying that the landscape documentation package, including landscape, irrigation, and grading designs have been prepared in accordance with the provisions of this chapter and the Water Efficient Landscape Guidelines and containing the following:
a. 
The statement: "I have complied with Chapter 17.89 of the City of Hawthorne Municipal Code and the Water Efficient Landscape Guidelines and applied them for the efficient use of water in this landscape design plan," and
b. 
The professional stamp, contact information, and signature of the California-licensed landscape architect who prepared the landscape plan.
B. 
Final Approval after Installation. Upon installation and prior to final inspection and approval, the applicant shall submit a certificate of completion (Appendix D of the Water Efficient Landscape Guidelines) to the planning department that includes:
1. 
Project information sheet containing:
a. 
Date,
b. 
Project name,
c. 
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;
3. 
Irrigation scheduling parameters used to set the controller;
4. 
Landscape and irrigation maintenance schedule;
5. 
Irrigation audit report conducted by a third party certified landscape irrigation auditor;
6. 
Soil analysis report, if not submitted with landscape documentation package, and documentation verifying implementation of soil report recommendations;
7. 
Documentation showing that copies of the approved certificate of completion has been submitted to the local water purveyor and property owner or designee.
(Ord. 2140 § 11, 2017)