STEVE INSKEEP, HOST:
Many cities across this country have paved over their streams, often to make way for urban development. The streams go underground. Now cities are realizing that uncovering those streams can have environmental and economic benefits.
Ann Thompson of member station WVXU reports so-called daylighting could be coming to a stream near you.
ANN THOMPSON, BYLINE: Cincinnati is under a government mandate to reduce its combined sewer overflows. This is because for years, heavy rains have caused those combined sewers to back up into buildings and overflow directly into local creeks and rivers. Part of the solution is bringing a stream buried 100 years ago to the surface.
(SOUNDBITE OF STREAM)
THOMPSON: This is the sound of the one place where Lick Run sees daylight before heading to a sewage treatment plant. It was put underground in a 19-inch pipe for urban development. In another two years or so, a mile of it will be above ground and serve as a buffer to slow the flow of stormwater.
Deputy Director of the Metropolitan Sewer District, Mary Lynn Loder, stands on a hillside in Cincinnati's South Fairmount neighborhood...
(SOUNDBITE OF CONSTRUCTION)
THOMPSON: ...where dozens of buildings are being bulldozed to make room for the stream. She points to where Lick Run will be daylighted.
MARY LYNN LODER: So it's going to have some plantings, some trees around it, an access path, a bike trail.
THOMPSON: One of first daylighting projects was 30 years ago in Berkeley, California. They revitalized Strawberry Creek which had been covered by a rail yard and turned the area into a park which is now an integral part of the community.
Experts say uncovering these lost streams is an opportunity to breathe life back into forgotten creeks and surrounding communities. That happened in Yonkers, New York with the daylighting of Saw Mill River in 2011. The documentary "Lost Rivers" captured the excitement.
(SOUNDBITE OF DOCUMENTARY, "LOST RIVERS")
(SOUNDBITE OF MUSIC)
THOMPSON: Ann- Marie Mitroff, whose group Groundwork Hudson Valley helped lead the Sawmill revitalization, says the $48 million project now protects against flooding and the economic benefits are big.
ANN-MARIE MITROFF: Beforehand, there were people who owned building, you know, along this stretch of a parking lot. It's kind of like why would you invest around a parking lot? Now it's a beautiful park with a river flowing through it.
THOMPSON: It's been almost seven years since Seattle spent $14 million to uncover Thornton Creek. It's spurred $200 million in private development, including a retirement community and a movie theatre.
Back in Cincinnati, Mary Lynn Loder is counting on similar revitalization, flood control and a cost savings for taxpayers when the Lick Run project is finished.
LODER: So it's really about repurposing our assets and considering, how can we get the biggest value for our ratepayers as we're embarking on project Groundwork?
THOMPSON: She says daylighting Lick Run is $200 million cheaper than replacing the pipes underground to contain it. The EPA is holding up Cincinnati's project as a national model. Other cities are watching. San Francisco, New Orleans and Washington, D.C. have called to find out how the project will work. And there's another benefit: It gives people a chance to experience nature without leaving the city.
For NPR News, I'm Ann Thompson in Cincinnati.