All landscape projects subject to the provisions of this chapter shall comply with the following irrigation requirements:
(a) Irrigation system.
(1) All irrigation systems shall be designed and installed to meet irrigation efficiency criteria as described in the Maximum Applied Water Allowance.
(2) Backflow prevention devices shall be required to protect the water supply from contamination by the irrigation system.
(3) Manual shut-off valves 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.
(4) Weather-based self-adjusting irrigation controllers with rain sensors shall be required.
(5) Pressure regulators and/or booster pumps shall be installed so that all components of the irrigation system operate at the manufacturer’s recommended optimal pressure.
(6) Irrigation systems shall be designed to prevent runoff or overspray onto non-targeted areas, such as adjacent property, non-irrigated areas, hardscapes, roadways, or structures.
(7) Point source irrigation is required where plant height at maturity will affect the uniformity of an overhead irrigation system.
(8) Low volume irrigation is required in mulched planting areas.
(9) Areas less than ten (10) feet in width in any direction shall be irrigated with subsurface irrigation or other means that produces no runoff or overspray.
(10) Overhead irrigation shall not be permitted within twenty-four (24) inches of any non-permeable surface unless the irrigation audit confirms no overspray or runoff occurs.
(11) Slopes greater than fifteen (15) percent shall be irrigated with point source or other low-volume irrigation technology.
(12) Sprinkler heads, rotors, and other emission devices on one valve shall have matched precipitation rates, unless otherwise directed by the manufacturer’s specifications.
(13) Head to head coverage shall be required unless otherwise directed by the manufacturer’s specifications.
(14) Swing joints or other riser protection components shall be required on all risers subject to damage that are adjacent to hardscapes or in high traffic areas of turf.
(15) Check valves or anti-drain valves shall be required on all sprinkler heads where low point drainage could occur.
(16) When landscape projects are services by a community water system, landscape water meters, defined as either a dedicated water service meter or private submeter, shall be installed for all non-residential irrigated landscapes of one thousand (1,000) square feet but not more than five thousand (5,000) square feet (the level at which Water Code 535 applies) and residential irrigated landscapes of five thousand (5,000) square feet or greater. A landscape water meter may be either a customer service meter dedicated to landscape use provided by the local water purveyor; or a privately owned meter or submeter.
(17) Master shut-off valves are required on all projects except landscapes that make use of technologies that allow for the individual control of sprinklers that are individually pressurized in a system equipped with low pressure shut down features.
(18) Flow sensors that detect high flow conditions created by system damage or malfunction are required for all non-residential landscapes and residential landscapes of five thousand (5,000) square feet or larger.
(19) All irrigation emission devises must meet the requirements set in the American National Standards Institute (ANSI) standard, American Society of Agricultural and Biological Engineers’/ International Code Council’s (ASABE/ICC) 802-2014 “Landscape Irrigation Sprinkler and Emitter Standard.” All sprinkler heads installed in the landscape must document a distribution uniformity low quarter of 0.65 or higher using the protocol defined in ASABE/ICC 802-2014.
(b) Hydrozones.
(1) Irrigation systems that serve trees shall be exclusively low volume type, and shall be placed on separate valves except when planted in turf areas. The mature size and extent of the root zone shall be considered when designing irrigation for the tree.
(2) Distinct hydrozones shall be irrigated with separate valves.
(3) Sprinkler heads and other emission devices shall be selected based on what is appropriate for the plant type within that hydrozone.
(Ord. 1445, eff. August 14, 2014; as amended by § 15, Ord. 1466, eff. March 24, 2016)