rain Tag

Putting the LID on Stormwater Runoff

The following post is provided by guest blogger Thomas Powers, P.E., LEED AP, CFM, CPESC, A Project Manager with Wight & Company in Chicago Illinois and former colleague of The Inlet's Carolyn Howard. [caption id="attachment_688" align="alignleft" width="234" caption="Thomas Powers, PE, LEED AP, CFM, CPESC"][/caption] How many gallons of rain do you think falls each year on just one acre of land in Norfolk, Va.? Ten thousand? One hundred thousand? Would you believe more than one million? Unfortunately, most of that water isn’t absorbed by the land and instead becomes stormwater runoff, carrying debris, chemicals, sediment or other pollutants. The U.S. Environmental Protection Agency (EPA) ranks urban runoff and storm-sewer discharges as the fourth most prevalent source of impairment of our lakes, streams and rivers. The current best practices in stormwater management is called low impact development (LID), which refers to a comprehensive land planning and engineering design approach that emphasizes conservation and the use of...

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Cisterns and Stormwater

[caption id="attachment_206" align="alignleft" width="200" caption="Rainwater collection system at Northside Family Learning Center, Richmond, VA"][/caption] Cisterns make sense, why not use stormwater as resource and reduce the demand on potable water supply systems. I have successfully designed cistern systems, I encourage the use of cisterns, and I look forward to the standardized methodology to calculate benefits in the proposed regulations http://www.vwrrc.vt.edu/swc/NonProprietaryBMPs.html . However, I feel that there are some misconceptions about cisterns that need to be addressed: If the cistern is used only for irrigation, then the cistern does nothing for reducing stormwater impacts in the 6 or 7 months out of the year when there is no irrigation. Cisterns used solely for irrigation need to overflow to another measure, such as bioretention.  Is there a stormwater benefit for a measure that works for only half of the year  Rainfall is unpredictable. In the last ten years in Richmond, the annual rainfall varied by...

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