The Public Utilities Commission, the Department of Public Health, and the Department of Building Inspection have partnered to encourage the safe use of rainwater for irrigation and toilet flushing without requiring special treatment. Systems designed to collect and treat rainwater for any potable uses will be inspected and permitted on a case- by-case basis.
What is rainwater harvesting?
Rainwater harvesting is the practice of collecting and using rainwater from hard surfaces such as roofs. It is an age-old technology that is growing in popularity as people look for ways to use water resources more wisely. Communities in ancient Rome were designed with individual cisterns and paved courtyards, which captured rainwater to augment supply from the city’s aqueducts.
Until recently, urban areas served by municipal water have tended to overlook rainwater as a water resource. San Francisco would like to change that by raising awareness about rainwater harvesting and promoting its use.
Why harvest rainwater?
When you install a rainwater harvesting system at home, you are helping to maintain the health and beauty of San Francisco’s urban watershed in many ways. By harvesting rainwater you:
- Keep relatively clean water out of the combined sewer system and make it available for use
- Reduce the energy and chemicals needed to treat stormwater in San Francisco’s combined sewer and the energy expended transporting water from far away
- Reduce the volume and peak flows of stormwater entering the sewer, thereby reducing flooding and combined sewer overflows
- Reduce the volume of potable water used for non-potable applications such as irrigation and toilet flushing
Getting Started:
Click here to download our rainwater harvesting brochure.
Resources:
Green Dean TV: Installing a Rain Harvester
YouTube: Rain Water
Contact Information
If you are interested in learning more about rainwater harvesting, please contact Sarah Minick at sminick@sfwater.org.
Rainwater harvesting workshops organized by the SFPUC’s Stormwater Management Program enjoyed high turnout and an enthusiastic reception at the Neighborhood Empowerment Network’s (NEN) Clean and Green Summit. Read more
