SACRAMENTO, CALIF. — Another rainwater recovery and re-use statute is wending its way through the California legislature. Assembly Bill 1750, the Rainwater Capture Act of 2012, was introduced in February and is currently residing in the Senate Committee on Environmental Quality. The bill shares some similarities with its predecessor, AB 275, which was introduced last year by Assemblyman Jose J. Solorio, and ultimately vetoed by Gov. Edmund G. Brown Jr.

AB 275 was doomed because it circumvented the authority of the California Building Standards Commission on rainwater systems. BSC Executive Director Jim McGowan is a cabinet level officer in California and he let it be known that he didn’t like the incursion onto his turf.

AB 1750 reads, “10572. Nothing in this part shall be construed to do any of the following: … (d) Impair the authority of the California Building Standards Commission to adopt and implement building standards for rainwater capture systems pursuant to existing law.”

The bill covers rainwater captured for outdoor use and indoor use. Rain barrel or cistern systems for landscape irrigation on private property are unfettered as long as their capacity is less than 360-gal. Landscape contractors may install all of the exterior components for a rainwater re-use system, as long as none of it is attached to a structure.

Any landowner can install and use a rainwater recovery system if it complies with the following restrictions.

A) The system complies with the California Building Standards Code.

B) The system includes supplemental filtration, a disinfection device, or other process or device that performs an equivalent function, as determined by the local agency having jurisdiction.

C) The local agency with jurisdiction over the enforcement of building standards consults with the local department of public health regarding public health impacts before issuing the first indoor-use permit or establishing a rainwater capture program, agrees to issue a permit for the system, and inspects the installation of the system before the system is operated, and the landowner complies with the conditions and requirements imposed by the permit. The local department of public health may impose conditions on permits for indoor use of rainwater.

D) The rainwater is used for non-potable uses, including toilets, urinals, clothes washing machines, or heating, ventilation, and air-conditioning systems, or other uses allowed by the California Building Standards Code.

Further down in the bill, it restates that a rainwater capture system that is a part of, or attached to, a structure regulated by the California Building Standards Code must be installed and used consistent with applicable requirements of the California Building Standards Code.

Backflow prevention is required if there’s any connection with the potable water system.

E.W. “Bob” Boulware, Design-Aire Engineering, Indianapolis, and president of the American Rainwater Catchment Systems Association, has reservations about the definitions of rainwater and stormwater contained in the bill.

The legislation defines rainwater as precipitation that has not entered an offsite storm drain system or channel, a flood control channel, or any other stream channel, and has not previously been put to beneficial use.

"Rainwater capture system" means a facility designed to capture, retain, and store rainwater flowing off a building, parking lot, or any other manmade, impervious surface, for subsequent onsite use.

"Stormwater" means temporary surface water runoff and drainage generated by immediately preceding storms.

Boulware doesn’t like the provision that rainwater can hit the ground and run off a parking lot. Because of that, AB 1750 requires filtration and disinfection. To Boulware, rainwater means pure, as long as the roof is kept clean and the system is maintained.

"You can run it back into the building, filter it and use it for makeup water for interior fountains or flush johns with it pretty much as it comes off the roof,” Boulware noted. “Surface water, water that hits the ground and goes across the ground on roads or driveways or runways is viable water, but ARCSA’s position is that it has different qualifications than rainwater and needs to be treated differently.”

The definition in the bill, Boulware said, makes rainwater the equivalent of graywater and requires the same filtration and sterilization. He also worries that the legislation gives too much discretion to AHJs, who might require water utility standards of purity. That would make rainwater systems so expensive that they would not be applied.

If AB 1750 fails, rainwater systems would be approved for use in California anyway. The BSC is updating the California plumbing code based on the 2012 Uniform Plumbing Code published by the International Association of Plumbing & Mechanical Officials. The 2012 UPC contains the rainwater provisions in the IAPMO Green Plumbing & Mechanical Code Supplement. Additionally, IAPMO has supplied the BSC with portions from the 2012 GPMS that include updated water quality parameters for rainwater harvesting systems.