Call it a collaboration of infiltration—the U.S. Environmental Protection Agency and the City of Philadelphia agreed yesterday to become partners in a 25-year plan to use green infrastructure to manage stormwater runoff. In a signing ceremony at the Fairmount Water Works, EPA Administrator Lisa Jackson joined Mayor Nutter, PWD Commissioner Howard Neukrug and other officials to assure the EPA's support for Green City, Clean Waters. The long-term plan aims to restore water quality in our local rivers and streams by absorbing rain water into the ground; green infrastructure such as tree trenches, green roofs and rain gardens mimic natural processes that intercept and infiltrate rain water before it enters the sewer. 

Philadelphia Inquirer reporter Sandy Bauers expanded on the issue and the economic advantages of green infrastructure in today's front-page article:

"Philadelphia's problem is that about 60 percent of the city's sewers are a combined system that carries both sewage and storm water. During heavy rainfall, the system overflows, and untreated water containing raw sewage, litter, road pollution, and other substances spurts from more than 150 overflow pipes into streams and rivers. The overflows total about 14 billion gallons a year. Many other large cities have decided to build massive—and hugely expensive—underground tunnels to solve the problem. Washington proposed three of them, the largest eight miles long and 23 feet in diameter. Philadelphia had considered it, but then realized it might be looking at the wrong end of the pipe. Instead of managing what came out of the sewer system, perhaps it could manage the water before it enters the system."

More photos from the signing ceremony after the jump.

You're invited: On Thursday, April 5 from 2:00-4:00 p.m., the University of Pennsylvania will be hosting a panel discussion on Urban Watersheds in the Hall of Flags, Houston Hall. The discussion will focus on community involvement and watershed partnerships. Speakers include Jon Capacasa (EPA), F.N. Scatena (UPenn Dept. of Earth & Environmental Science), Phillip Rodbell (USDA Forest Service) and PWD's own Valessa Souter-Kline.

We are sure this discussion will be interesting, but let's be honest with ourselves: We really just want to hang out in a place called the Hall of Flags for a little while.

Email marthap@sas.upenn.edu for more details.

The Philadelphia Inquirer offered coverage of Wednesday night's panel discussion on iodine-131 at the Fairmount Water Works Interpretive Center. Officials from PWD, the EPA, Pennsylvania DEP and the city Department of Health were able to confirm that detected levels of radioactive iodine-131 are due to thyroid patients who pass the substance to waterways through their urine. (I-131 is used to treat about half of thyroid-cancer cases in the area.) While the levels of iodine-131 pose no risk to public health in Philadelphia, some questions remain. According to the article: 

"One mystery officials have pondered is why iodine-131 isn't showing up in many other places, or is found at lower levels than they see here. One reason: most other cities aren't looking for iodine-131. Plus, the Philadelphia region is a medical center, and a lot of sewage-treatment plants discharge into waterways that then flow past Philadelphia and into its drinking-water intakes."

Visit our Iodine-131 information page, which includes FAQs, fact sheets and links to more news items.