With the release of new rules for the use of nonpotable water in businesses and apartment buildings, San Francisco is riding a new water conservation wave.
The 23 pages of draft rules are part of San Francisco’s effort to create a clear process for new commercial and residential developments to install nonpotable water systems for uses such as irrigation and toilet flushing. The effort is part of a global construction trend to incorporate nonpotable water in development.
Within the last year, developers have expressed more interest in such systems, prompting the need for regulations, said June Weintraub, a senior health official with the Department of Public Health. Such systems conserve water, help building projects obtain LEED certification, and reduce a landlord’s sewer and water costs.
The rules will govern collection and reuse of rainwater from rooftops, surface drainage and subsurface collection, as well as the two grades of building wastewater: graywater from showers and bathroom sinks, and blackwater from toilets and kitchen sinks. Depending on the source, such water can be used for irrigation, fountains, laundry, toilet flushing, cooling applications or dust control.
The rules address inspections, permit requirements and water testing. City oversight increases depending on the type of water used, with permit fees ranging from $1,544 to $9,034. The mere use of rainwater for irrigation requires no permit.
For more complex uses, sampling, testing and water quality reporting are required to protect against bacteria, offensive odors and high chlorine levels. Public Health would be allowed to inspect such systems without notice.
Noncompliance could lead to permit suspension or penalties of up to $5,000 for repeat offenders.
“There has to be oversight to make sure they will not be putting tenants at risk,” Weintraub said. The regulations would apply to buildings of three or more units.
City departments have only reviewed two such systems in the last year, including the new home of the San Francisco Public Utilities Commission at 525 Golden Gate Ave. But many more are expected, including at the new Transbay Transit Center and Moscone Center expansion.
The Golden Gate Avenue building supplies toilets and irrigation with nonpotable water. The system is expected to recycle 5,000 gallons of wastewater daily and store 25,000 gallons of rainwater, saving nearly 800,000 gallons of drinking water annually.
In September, the Board of Supervisors unanimously approved legislation from board President David Chiu requiring city permits for such systems and the establishment of these rules.
The commission is now offering grants of up to $250,000 for large projects incorporating nonpotable water use. Projects would have to flush all toilets with nonpotable water or replace 40 percent of their total water use with nonpotable water to be eligible for a grant. A public comment period on the proposed rules is open until Jan. 28.