For years, local efforts to reduce pollution in the Chesapeake Bay have focused on nutrient runoff from farm fields and sediment from cows in streams.

Now, Lancaster city and the nonprofit group LIVE Green are taking a more urban approach to the problem.

On Thursday, the city received a $400,000 grant from the Chesapeake Bay Program and National Fish and Wildlife Foundation through the federal Environmental Protection Agency. The federal funds will be matched dollar for dollar with money from the city's wastewater capital fund, said Charlotte Katzenmoyer, city public works director.

The combined $800,000 will be used to fund six or more pilot projects intended to divert storm water runoff that now goes into the city's sewer system, said Danene Sorace, executive director of LIVE Green.

Heavy rainstorms can overwhelm the capacity of the city wastewater treatment plant and cause untreated sewage to flow into the Conestoga River, and ultimately the Chesapeake Bay. The city has been under increasing EPA pressure to limit the overflows, but separating the city's old sewer system from its storm water drains is likely to cost hundreds of millions of dollars.

Previously, Katzenmoyer put a $70 million price tag on a plan to build an underground holding tank where storm overflows could be held until the water could be treated.

The grant will be used to develop cost-effective alternatives that can reduce storm water run-off, Sorace said.

President Barack Obama last year ordered the federal EPA to take charge of the bay clean up after decades of unmandated and unmet goals by state leaders.

Sorace said the local effort is intended to be proactive by coming in advance of federal mandates.

"Before the EPA acts in a way that maybe won't be the most helpful to the city, we're trying to get out ahead of that in a way that is best for the city, and that is with green infrastructure," she said.

Details of the pilot projects have not been finalized, but Sorace said they might include the use of porous pavement on basketball courts in city parks that will allow rainwater to soak into the ground rather than run into storm drains.

She also cited as a problem public parks where gutters now divert rainwater away from porous grass, trees and playgrounds and into storm drains.

Another effort likely will be an inventory of the city's street trees that could be followed by additional tree plantings where needed. Trees help absorb groundwater and clean the air, she said.

The pilot projects will be done in cooperation with the Lancaster County Planning Commission, which will use them as examples for other municipalities in the county's urban growth areas, said Katzenmoyer.

They also are being done in cooperation with the state Department of Conservation and Natural Resources and the EPA.

The state agencies will show the results to other Pennsylvania cities with similar combined storm systems, such as Harrisburg, Allentown, Scranton and Wilkes-Barre, Katzenmoyer said. All of those cities are within the Chesapeake Bay watershed.

Sorace said the projects will come from a Green Infrastructure Plan now being drafted by a Philadelphia environmental consultant. That plan, funded in part from a $70,000 state grant, is expected to be released in draft form next month.

The effort builds on work already done by LIVE Green, a component of the nonprofit Lancaster Investment in a Vibrant Economy, or LIVE. LIVE Green has held workshops promoting the use of vegetative "green" roofs and rain barrels, in which residents collect rain water from down spouts to water their plants.

She emphasized the low cost of such measures.

"Green infrastructure will allow us to do more with less," she said.

A draft of the city plan will be discussed at a public briefing on Sept. 23, at 1 p.m., at Southern Market Center, 100 S. Queen St.

bharris@lnpnews.com