The long-running battle over whether developers would be required to undertake costly measures to capture storm-water runoff from their new L.A.-area projects appears to finally be over.

And the developers have lost.

Beginning in February, they will be required to install water-retention basins, absorbent grassy spillways or other such elements to keep polluted storm-water runoff from draining into Santa Monica Bay.

The requirements the first of their kind in the state will apply to all new single-family hillside homes, subdivisions with 10 or more homes, 100,000-square-foot commercial developments, automotive repair shops, restaurants and parking lots over a certain size in Los Angeles County. Excluded are projects in Avalon, Palmdale and Lancaster, which are outside the regional board's jurisdiction. The new rules also will apply to redevelopment projects that add or improve 5,000 square feet of space, or more.

The water-capturing elements must be capable of handling water from any storm that produces three quarters of an inch of rain in 24 hours.

"It is still an economic burden and the costs will certainly be passed along to the homebuyer, but it is probably unlikely we will appeal," said David Smith, general counsel to the Diamond Bar-based Building Industry Association of Southern California, which counts 1,800 members. "There will eventually be litigation over storm-water regulations, but I don't think this is the case we want to take forward (to the courts)."

The Los Angeles Regional Water Quality Control Board first passed the requirements for L.A. last January, prompting the BIA to appeal the matter to the state board. On Oct. 5, the state board upheld the rules, and the BIA has decided not to take its challenge any further.

Similar rules were adopted by the board in July for Ventura County and are already in effect. Local water-quality regulators defended the rules as being a reasonable step toward protecting the environment.

"The way sites have been developed is basically to clear the runoff and send it to the storm drain as quickly as possible," said Xavier Swamikannu, chief of the regional board's storm water program. "This requires a whole new way of looking at things, rather than simply pave and go away."

Environmentalists, as expected, hailed the new rules.

"It's the first real step in the right direction in changing the ways we do development in this region, so we decrease the amount of pollution, rather than our past history of rampant increases with each new and redevelopment project," said Mark Gold, executive director of Heal the Bay, the Santa Monica-based group dedicating to improving Santa Monica Bay.

Improving the health of Santa Monica Bay is one of the primary goals of the regulations, which are based on amendments to the Clean Water Act of 1972.

The board contends the regulations will only increase developers' costs by 0.5 to 1 percent, meaning $1,250 to $2,500 for a new $250,000 home.

But in the Seattle area, where the building industry has had to grapple with such regulations since the early 1990s, the regulations have been stricter and the costs have been far higher.

"We have found that a typical medium-to-large size development of 100 to 150 homes comes to about $7,000 per lot," said Bob Johns, general counsel for the Master Builders Association King County Council, an association of some 2,500 builders in the Seattle metropolitan area. "But a 10-unit townhouse could get to $15,000. People don't realize how much this stuff costs. It's pretty breathtaking."

The Seattle-area regulations essentially require runoff control measures capable of capturing or treating about 90 percent of all rainfall, while the L.A. measures call for about 80 percent.

Johns said if the Los Angeles experience is anything like Seattle's, builders can expect to absorb the costs initially. Eventually, as new homes required to have such measures continue to hit the market over the years, those added costs will be reflected in market prices, at which point builders will be able to pass along the added costs to homebuyers.

"It's a pass-through to the buyer, but in the short run the builders take it in the shorts," Johns said. "It took about three or four years for the market to adjust."

Ultimately, the area housing industry could be put at a competitive disadvantage, compared to other regions not under the regulations. But other regional boards, including those in San Francisco and San Diego, are considering similar storm-water runoff standards.

"If another (regional) board wants to put that kind of language in, they know the state board has ruled on it," said Robert Miller, a spokesman for the state water board. "It's precedent setting."

Amid all the grumbling, the BIA has hired a former Los Angeles County civil engineer to help it assist its membership in meeting the regulations. But still, developers complain that the new rules are unfair, since they don't apply to existing properties, which are the source of much runoff.

"They have done nothing to address what is already in the gutters and running into the bay," Smith said.

Environmentalists counter that, while the new rules will not totally solve the problem, they are an important first step.

"Essentially, this is a way to keep the problem from getting worse," said Alex Helperin, a staff attorney with the Natural Resources Defense Council in Los Angeles, a leading advocate of the new regulations. "It's not the ultimate fix."

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