Cities faced with stormwater pollution problems like Chattanooga are trying to slow rain runoff before the stormwater and the money spent to treat it goes down the drain.

During a Clean Water conference in Chattanooga, officials from Philadelphia and Milwaukee touted the ways they have already slowed runoff by shifting some responsibility from local government to landowners.

The plans from the cities, some borrowed from Chattanooga, call for scaling back parking lots, narrowing public streets and ditching curbs and gutters in favor of rain gardens, green roofs and street planters.

Direct development by the city, combined with new rules that require landowners to build stormwater management systems or pay high sewage bills, make up part of the program.

Opponents of these plans say the price tags are too high and drive up the cost of doing business in Chattanooga. But backers say that it's simply the best way to deal with a wave of unavoidable and still more costly EPA regulations on stormwater.

The green push for stormwater treatment has intensified in the face of a looming consent agreement between Hamilton County and environmental regulators that could cost taxpayers well over $100 million through the use of traditional underground pipes and tanks to redirect and contain runoff.

A national group of city planners say that green solutions -- which trap water before it hits the tanks -- cost less, do the same job and look better.

And they say they have jobs to prove it -- jobs that could have gone to Chattanooga, they say.

"Either do it or get out-competed by Milwaukee and Philadelphia," said Brian Reilly, executive director for the Municipal Land Use Center at the College of New Jersey.

In older cities like Milwaukee and Philadelphia that combine sewage and stormwater systems into one runoff stream, excess rainfall overflows along with raw sewage into nearby lakes, streams and rivers. In Chattanooga's case, that means flooding the Tennessee River with pollutants.

If city and county officials fail to present solutions, those solutions could be forced on them by regulators -- along with hefty fines for noncompliance.

Local efforts are still in the planning stages. Some early green projects on Manufacturers Road and at Eastgate Town Center could use landscaping and permeable surfaces to reduce runoff there, according to Karen Hundt, the director of the city's planning and design studio.

But a flare-up over a $341,169 green roof on the Chattanooga City Council building has some worried that a "green" agreement with the EPA could be sidetracked.

Councilwoman Deborah Scott called the cost "outrageous," though she was overruled by the rest of the council.

"We will never get this done if some group is offended by the word 'green,'" said David Crockett, director for Chattanooga's Office of Sustainability.

The green roof may be more expensive in the short term, he said, but it will stand through what would be three or four more roof replacements in the future, lower the city's runoff fee and lower the city's heating and air conditioning costs.The way Crockett and crew look at it, it's a choice between a higher initial investment or higher overall costs.

"You've got an EPA gun to your head," Reilly said. "Why do you tolerate lower return on investment when you've got a green option?"

Philadelphia was faced with more than $12 billion in compliance costs to fix its stormwater system with regular pipes and underground tanks. During negotiations, the city reduced its cost to about $4 billion in public outlays and private money through green projects and new fees, said Marc Cammarata, director of the office of water sheds for the Philadelphia Water Department.

"The money simply isn't there to do what the EPA requires," Cammarata said. "When you're limited by affordability, you can go green in pieces, instead."

The main point of contention for property owners is what to do about 25 percent of Chattanooga that is made up of impervious surfaces, planners say.

New options like planting trees or covering a roof with grass can seem like an insignificant gesture, but ultimately prevent acres of water from rushing directly into an already overloaded sewer system, Cammarata said.

Without broad agreement from government agencies, businesses and the public, green projects don't work at the state and local levels, cautioned officials from Milwaukee and Philadelphia. A permeable road project that allows stormwater to penetrate the asphalt instead of washing away into local storm sewers will require cooperation from the road and sanitation departments, for instance.

"To decrease these costs and increase value, you build roads differently, you build parking lots differently, everything you do changes," Crockett said. "They have to be on the same page."