Filter Solves Urban Storm Water Runoff Problems?

If you think that chemical factories, or steel mills, or mining are the biggest causes of water pollution in WV, you'd better go take a look in a mirror. The fact is, storm water runoff, so-called nonpoint source runoff, is a greater problem. All those lawn chemicals you use, the salt you put on your sidewalk and the city puts on your roads, the body waste from your pets, the oil that drips from your car, the gas that spills out of your car tank, . . . well, you get the point. All of that lies around on the ground, waiting to be carried off by the next heavy rain that can flush it into the city's storm sewers, or directly to a stream.

If a city's storm sewers carry the runoff directly to the river, the loading of chemicals and pathogens can be tremendous. If the storm sewers carry the water to the sanitary sewer for treatment, a heavy flow can overwhelm treatment, causing the city to bypass treatment and dump storm water and raw sewage into rivers, in something called a combined sewer overflow, or CSO. Fixing these systems, which require constructing huge amounts of storage, or additional treatment capacity, or rerouting sewers, is tremendously expensive, and cities have lagged in doing it. When they do it right, as I believe Charleston is, you're going to see large increases in sewer fees to pay for it.

Glenn Rink thinks he has the answer with a special filter that can be put in catch drains and at the end of storm water pipes. The filter not only catches sediment and other particles, it absorbs oil and certain other pollutants. I hope he's right, but I have a few questions - does it capture all, or even many, of the pollutants that are removed by conventional treatment? How often must filters be replaced? How much does it cost to change out and dispose the filters? Having said (or asked) that, this sounds like a great idea, if only to provide treatment for storm water while cities are looking for other, more permanent solutions.