Rainwater Harvesting: Rain Barrels
The California Plumbing Code has no approved standards for rainwater harvesting systems. No permit or city approval is needed for rain barrel systems of 100 gallons or less per vessel, provided all city requirements are met. Rainwater catchment systems over 100 gallons require permits and approval from the City of Berkeley Building Department. Download Guide to Conserving Water Through Rainwater Harvesting and Graywater Reuse (.pdf)
Rain Barrel System Requirements:
- Rain barrels shall be sited at grade on a sound and level surface at or near gutter downspouts.
- Water collected shall be used for irrigation only.
- Rain barrel openings shall be screened with a fine mesh (.05 inch x .05 inch) to prevent mosquitoes from entering.
- Gutters serving rain barrels shall be debris screened.
- Large openings shall be securely fastened to prevent accidental drowning.
- No pumps, connections to domestic water or interior use are permitted.
- Rain barrels shall be located a minimum of 3 feet from the property line.
- Overflow from rain barrels may not discharge across the public right-of- way or adjacent property, or create a nuisance.
- Collection vessel(s) for each existing downspout shall not exceed 100 gallons in the aggregate.
- Rain barrels and gutters shall be cleaned annually.
- Rainwater from rain barrels is not required to be treated.
- Use of rainwater collected from rain barrels is not limited to sub-surface irrigation.
- The system shall be used and maintained in a manner that does not cause a public nuisance and may be subject to inspection and/or enforcement action as a result of a complaint.
Note: Rain catchment systems over 100 gallons or over 100 gallons in aggregate per downspout will be considered cisterns subject to the permitting requirements.
- Your rain barrel should have a spigot/faucet so that you can access the water, an overflow pipe, a sealed and screened lid with an opening to attach your downspout and screens on all vents. Label all rainwater harvesting pipes and barrels with: “Non-Potable Water, Do NOT Drink”.
- All rainwater collection systems must have an overflow to a safe disposal location (stormwater drain or rain garden).
- If you intend to water edible plants with your rainwater, consider installing a first flush diverter, which disposes of the first inch of rain and ensures that you harvest only the cleanest rainwater.
- Rain barrel must be secured on a firm, level surface so that it will not tip over. It can be raised slightly to help with gravity flow irrigation.
- The barrel should be a food grade container, made to hold liquid.
Resources and Links:
City of Berkeley Guide to Conserving Water Through Rainwater Harvesting and Graywater Reuse (.pdf)
City of Berkeley Rainwater Policy: Guidelines for Rainwater Harvesting (.pdf)
(see section on "No Permit Systems" for rain barrels)
City of Berkeley Website on Rainwater Harvesting
American Rainwater Catchment System Association: ARCSA
East Bay Municipal Utility District: (EBMUD)
Learn how to green your home, check out other Green Permit Guides
Back to Office of Energy and Sustainable Development Homepage