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City of Fernley Department of Public Works DESIGN STANDARDS 11.0- ALTERNATIVE WATER 11.1 GENERAL 11.1.1 APPLICABILITY All civil improvement plans shall include for approval, unless waived by Public Works, an alternative water configuration signed and stamped by a Nevada Registered Civil Engineer in accordance with Public Works standards. 11.2 DESIGN CRITERIA 11.2.1 PIPING CONFIGURATIONS Piping will follow potable water system piping configuration and design unless specifically identified in Section 11.0 – Alternative Water. A dry alternative water distribution main is required in all new streets as well as entire property frontage if improvements are made within the public right-of-way. The minimum diameter for alternative water distribution mains shall be eight inches. If an alternative water main exists in the street frontage of any project including civil improvement plans, the project shall be conditioned to connect to said main. This piping will only be utilized for non-potable use and must be located within public rights-of-way or public utility easements with a minimal of 10 feet of horizontal separation from potable water lines. Non-potable warning tape and trace wire shall be utilized. 11.2.2 COLOR - CODING All pump motors, piping, metering, and valving will be coated with a purple epoxy (2 coats). All air vac valve assemblies, flush valve assemblies, vault lids, and associated appurtenances shall be coated with purple epoxy. All buried piping shall be purple PVC or ductile iron. All non-purple piping including valving and fittings shall be entirely bagged in purple-colored polyethylene film and sealed. Non-potable water mains shall be installed at nominal depths of 36 inches below finished grade. 11.2.3 CROSS - CONNECTIONS Potable cross-connections and hose bib connections are not permitted. Overspray of the irrigation system will not be permitted on public drinking fountains and areas of land use not designated to receive non-potable water. Public workshops and notifications to homeowners will be conducted for public awareness of potential public health hazards with ingestion or physical contact with non- potable water. 11.2.4 METERS Each individual lot shall incorporate residential water meter boxes with purple lids unless a larger service is required. The meter boxes shall be located on opposite property lines from potable water meters. 11.2.5 SPRINKLER SYSTEM The sprinkler system shall be designed to preclude overspray onto land uses not suitable for non-potable water applications. The sprinkler system must be designed to preclude breeding of insects and creation of odors or deposits. Sprinkler systems shall AW-1 May 2008 ---PAGE BREAK--- City of Fernley Department of Public Works DESIGN STANDARDS be designed to apply non-potable water at a rate that does not exceed the infiltration rate to preclude run-off. Location of drinking fountains must be shown on the irrigation plans. Sprinkler over-spray will not be permitted on drinking fountains. Proper signage shall be included in the design indicating “CAUTION: NON-POTABLE WATER – DO NOT DRINK” at intervals not to exceed 50 feet. 11.2.6 QUICK COUPLERS Quick couplers shall be constructed of brass with a purple snap-on cover and shall have a ¾-inch or 1-inch inlet. All non-potable water quick couplers shall be installed below grade in a round box designed for irrigation use. The cover shall have a warning label identifying non-potable water and be purple in color. 11.2.7 FINAL INSPECTION Final alternative water system inspection is required prior to final acceptance by Public Works. 11.3 ONSITE GENERATED NON-POTABLE WATER (GRAY WATER) 11.3.1 DESIGN SUBMITTAL Alternative water supply for residential irrigation such as gray water systems shall be submitted to Public Works and the Building Department for review on a case-by-case basis. A study conducted by a licensed engineer must accompany submittals for consideration. The study must show that water production will be of sufficient quantity to sustain vegetative growth. The analysis must also show that production of water will be suitable for discharge onto the soil. 11.3.2 NON-IRRIGATION DISCHARGE The residential irrigation systems must be capable of providing adequate water during irrigation months and delivery of water to the public sewer during non-irrigation months. The water system must be capable of managing deposit of solids and prevention of septic conditions in the water collection chamber. The system application rate must be less than or equal to the infiltration rate of the soil to preclude runoff. AW-2 May 2008