InfraStructures - August 2010 - Suburban Chicago Conversation Group Gets Tips on Keeping Surface Water Clean

Suburban Chicago Conversation Group Gets Tips on Keeping Surface Water Clean

If you want clean streams, you need clean streets. That is the message Brian Giles, sweeper product manager for Elgin Sweeper, shared with the municipal officials and consulting engineers who comprise the DuPage River Salt Creek Workgroup of The Conservation Foundation. The Chicago-area organization focuses on helping local governments understand and apply best practices in environmental stewardship.

Mr Giles made the connection between street pollution and surface water pollution in his June 30 presentation to the workgroup in a meeting held at city hall in Elmhurst, Illinois, a Chicago suburb. He is a frequent speaker on environmental protection topics to public and private conservation groups.

During the presentation, Brian Giles described a variety of street surface pollutants that enter the sewers and, eventually, the waterways, paying particular attention to silt as a menace to clean streams. He said silt is inorganic matter less than 80 µ in diameter that tends to remain suspended in solution and is difficult to remove from surface water.

“Eighty percent of silt, or debris that could become silt, is located within several feet of the gutter,” Mr Giles noted. “It may be hard to believe, but the average street has about 285 kg of debris per kilometer. The key to preventing surface water pollution is to keep that debris from entering the storm sewers.”
Brian Giles cited data on the effectiveness of various sweeping technologies in removing silt from the streets, ranging from a low of 81% using standard wet dust-control mechanical sweepers, to a high of 98% using high efficiency regeneration sweeper technology.

“Sweeping is a classic pollution prevention technique,” he explained. “It removes pollutants before they enter the sewers and streams. Catch basin cleaning can be an important – although expensive – part of an overall strategy to keep sewers free of debris and silt. An effective sweeping program can help minimize that expense.”
Brian Giles advised municipal officials to become familiar with the science and technology of street sweeping, including the importance of frequent sweeping.
“As an industry, we have to help local governments understand that street sweeping can be an effective water-pollution prevention strategy,” Mr Giles emphasized. “It’s more than just making the streets look pretty.”

Source: Federal Signal Corporation