When installing Rain barrels and cisterns there are a few requirements that need to be followed. These requirements are listed below. (From County of Los Angeles Department of Public Health and Environmental Health.)Cross Connection & Water Pollution Control Program • 5050 Commerce Drive, Baldwin Park, CA91706 • Tel (626) 430‑5290 FAX (626) 813‑3025
Rain barrels and cisterns are methods of storing rainfall and runoff on-site for later landscape irrigational uses. In semiarid Los Angeles County, rainfall and runoff are resources and the reuse of the captured rainfall can reduce the amount of imported drinking water. For this reason and the reasons listed below there should be no reasonable impediment to storing and reusing rainfall and runoff, provided such can be done safely and with public health in mind. As a result of an increased interest and initiative to use untreated rain-fall/non-potable cistern water and urban run-off water for onsite landscape irrigation supply this Department has found it necessary to develop the following requirements for water pipeline construction, installation and safe reuse of these types on “non-potable” water supplies. The purpose of these requirements is to provide the necessary procedures to acquire approval for the installation of pipeline which will convey untreated rain-fall, nonpotable cistern water and/or urban run-off water for irrigation use. Moreover, it is intended to set requirements for the protection of the potable domestic water supply as well as public health.
Presently within the County of Los Angeles there are no regulatory definitions of rain-fall or non-potable cistern water or urban run-off that would categorize them as either recycled water or any other regulated water source. Presently these types of non-potable water sources are categorized within the scope of alternative non-potable water. Therefore rain-fall/run-off, non-potable cistern and urban run-off water, for the purposes of these requirements shall be recognized as an alternative non-potable water source and any regulation pertaining to the protection of the domestic water supply in relation to an alternative nonpotable water source shall apply.
The following requirements are intended to focus on projects which integrate below grade pipelines, pumps and large capacity holding tanks and not necessarily for rain barrels that collect rain-fall/run-off water from residential roofs and gravity fed to hand held hoses. For the residential types of projects which do not incorporate below grade plumbing, pumps and large capacity tanks, please contact your local City Building& Safety Department.
Treatment systems for rain, gray and urban run-off water for reuse in toilet flushing have been proposed but are not covered within these requirements. Contact Los Angeles County Bureau of Environmental Protection at (626) 430‑5270 for information regarding treatment strategies and reuse.
These requirements apply to onsite collection and reuse for same site only. Distribution of collected rainfall/non-potable cistern and urban run-off to other properties shall be evaluated by State Department of Public Health in conjunction with State Regional Water Control Board.
Rain-fall/run-off refers to water collected within a rainwater catchment system used to collect rain water run-off from a rain event, usually, but not always, from rooftops. Depending on the materials used and the methods of collection the resultant storage vessel or cistern may be either potable or non-potable.
Cistern a large receptacle for storing water; esp., a tank, usually underground, in which rain water is collected for use.
Non-potable Cistern refers to a rainwater catchment system which captures non-potable water run-off as in a BMP for the purposes of reusing the water in an irrigation system. Non-potable cisterns are distinct from Potable Cisterns that are installed and managed as potable water reservoirs/storage.
Urban run-off – refers to non-potable water from a dry weather run-off catchment system used for the collection of water run-off which does not necessarily come from a rain event.
Potable Water refers to water which is fit for consumption by humans and other animals. The U.S. Environmental Protection Agency (EPA) identifies contaminants that may adversely affect public health that occur in drinking water with a frequency and at levels that pose a threat to public health. The EPA establishes maximum contaminant levels (MCLs) (both biological and chemical) permissible in drinking water. These MCLs become enforceable standards that determine the potability of water.
Non-Potable Water refers to water which is not intended for human consumption. Two distinct variations are inclusive in this definition: Non-potable water from a potable source, via a dedicated backflow prevention device vs. untreated non-potable water from collection methods that never originated from a potable source. The term non-potable water is all inclusive with respect to the various non-potable water supplies mentioned within these requirements.
Rain-fall/ Non-potable Cistern Water refers to the harvested rainwater/stormwater collected within a cistern from a rain event and/or urban run-off. Cisterns in Los Angeles County serve as a secondary source for applications that do not require potable water, such as landscape irrigation, which can dramatically lower the potable water demand and reducing off-site rain-fall runoff.
Gray water refers to untreated waste water which has not come into contact with toilet waste. Gray water includes used water from bathtubs, showers, bathroom wash basins, clothes washing machines and laundry. It does not include waste water from kitchen sinks, photo lab sinks, dishwashers or laundry water from soiled diapers.
Recycled water (aka, reclaimed water) refers to tertiary-treated water produced from the three-stage treatment of municipal wastewater. Recycled water is allowable for full-body human contact but not for direct human consumption. Purple pipe is the designated pipeline material specifically allowed to convey tertiary treated recycled water. Other non-potable water sources as mentioned in these requirements shallnot use purple pipe. Untreated stored rain-fall/runoff should not be confused with tertiary treated wastewater, defined in Title 22 of the California Code of Regulations.
In order to minimize construction accidents resulting in pipeline breaks, infiltration of rain-fall/nonpotable cistern water from leaking water lines into domestic water lines, or accidental cross-connections between rain-fall/non-potable cistern water and potable water systems, maximum attainable separation of rain-fall/non-potable cistern water lines and potable water lines shall be practiced.
Parallel construction: there shall be at least a four foot (4’) separation for all pressure mains, all distances measured from pipeline outside diameter. In restricted areas where distances can not be maintained at four feet, the use of sleeved pipe is required.
Cross-Over construction: Perpendicular pipeline installation is set at a one foot (1’) separation, with potable above rain-fall/non-potable cistern water; full pipe length centered over crossing. Alternative Cross-Over construction (distance not maintained): Either the rain-fall/non-potable cistern water may be sleeved with the same class piping (usually schedule 40 pvc) for one full pipe length (minimum four feet) centered over the cross-over.
The rain-fall/cistern water system shall be constructed in conformance with potable water system construction standards and in accordance with all other governing codes, rules and regulations. Unused or abandoned potable water lines are to be severed as close to water mains as practical, capped and a four-foot section of abandoned line removed and the cap cemented under Health Department supervision.
Existing On-site piping – To the extent feasible, maximum separation of rain-fall/non-potable cistern water and potable water lines shall be practiced upon system addition or modification.
All rain-fall/non-potable cistern water main lines, valve boxes and appurtenances shall be identified to clearly distinguish between rain-fall/non-potable cistern water and potable water systems. Specific wording on identification tape shall be required. Evaluation shall be on a case-by-case basis, but with the understanding that the minimum requirement for pipeline identification is per the Uniform Plumbing Code. The following identification tape will be accompanied with respective tags of the same colors and wording for all valve boxes, vaults, control valves, quick couplers, outlets and related appurtenances, if applicable.
California Health & Safety Code
California Code of Regulations, Title 22.
Los Angeles County Code
2007 California Plumbing Code.