A proposed law would require new homes, larger developments and some redevelopments in Los Angeles to capture and reuse runoff generated in rainstorms.

The ordinance approved in January by the Department of Public Works would require such projects to capture, reuse or infiltrate 100% of runoff generated in a 3/4 -inch rainstorm or to pay a storm water pollution mitigation fee that would help fund off-site, low-impact public developments.

The fairly new approach to managing storm water and urban runoff is designed to mitigate the negative effects of urbanization by controlling runoff at its source with small, cost-effective natural systems instead of treatment facilities. Reducing runoff improves water quality and recharges groundwater.

Board of Public Works Commissioner Paula Daniels, who drafted the ordinance last July, said the new requirements would prevent 104 million gallons of polluted urban runoff from ending up in the ocean.


Under the ordinance, builders would be required to use rainwater storage tanks, permeable pavement, infiltration swales or curb bump-outs to manage the water where it falls. Builders unable to manage 100% of a project’s runoff on site would be required to pay a penalty of $13 a gallon of runoff not handled there -- a requirement the Building Industry Assn. has been fighting.

“The Building Industry Assn. is supportive of the concept of low-impact development and has invested a lot of time and energy in educating our members on those techniques and advancing those technologies,” said Holly Schroeder, executive officer of the L.A.-Ventura County chapter of the association.

“But when we now start talking about using LIDs as a regulatory tool, we need to make sure we devise a regulation that can be implemented successfully.”

Schroeder said that some building projects, such as those in downtown L.A. or areas where the soil is high in clay, would have difficulty with the 100% retention rule and that the $13-a-gallon mitigation fee is too high. A one-acre building on ground where runoff could not be managed on site, Schroeder said, could pay a fee as high as $238,000.


“We’re seeking flexibility to reflect the site circumstance,” she said.

At the urging of business groups opposed to an earlier draft, the Board of Public Works has acquiesced on some points.

“We worked out something with the business community that they can release the runoff if they first run the water over a high-efficiency bio-filtration system,” Daniels said. “In other words, they have to clean it first.”

The board also decreased the per-gallon mitigation fee from $20 to $13. The mitigation fees would fund public low-impact developments, such as the Oval Street project planned for Mar Vista, where 24,000 linear feet of parkway will be retrofitted with porous pavement, bio-retention basins and other water infiltration strategies designed to capture 2 million gallons of storm water that would otherwise flow to the ocean.


The ordinance next moves to the Energy and the Environment and the Planning and Land Use Management committees of the City Council, before going to a council vote and the mayor.

Daniels said she hoped the ordinance would be approved in the next six months and go into effect by 2011.

“I don’t want to waste another rainy season,” she said.

susan.carpenter@latimes.com