Connecting Communities With Better Stormwater Management (Part II)
On Oct. 17, the Southern Tier West Regional Planning Board, in cooperation with the STW Watershed Coalition, held its first annual Stormwater Management Conference for local public officials in Chautauqua, Cattaraugus and Allegany counties. This is Part 2 of my article on that conference, which was entitled “Connecting Communities with Better Stormwater Management.”
Donald W. Lake Jr., the professional engineer who has been a principal author of the New York State Department of Environmental Conservation’s stormwater manuals, was the second featured presenter. He reported that in 1995, soil erosion caused $44 billion in damage across the United States as cited in a report by Pimental, et al. In New York state, stormwater contributes to the impairment of 766 miles of streams and 157 square miles of lakes and reservoirs.
He noted that research shows many residential lawns are so compacted so as to function to be as impervious as blacktop. Very little rainfall soaks in-almost all runs off as stormwater. Because of this, the NYSDEC is now requiring contractors to undertake “soil restoration” on construction sites to make them more pervious to rain or melt water. He also noted that changes in the regulations require a higher percentage of precipitation be infiltrated on-site for construction, with the purpose of reducing the peak flows and total annual volume of runoff from developed sites. This is meant to reduce downstream creek erosion in a majority of storm events. This will help protect private properties and public infrastructure, such as roads, bridges and culverts from stormwater and flooding damage. He also noted that pollutants are constantly falling onto the earth’s surface as “dry fall” and as part of precipitation. If they fall on rooftops, parking lots or other impervious surfaces, all are washed into the stormwater system in the “first flush” in rainfall or melting events. He noted that dog feces not only contain bacteria and other pathogens but also commonly contain living parasites – and no one wants to have those entering into waterways!
The old way of handling stormwater was to build an “end of pipe” facility, such as a stormwater detention pond, to store runoff from the rainfall event and release it over a few days. Research has shown this approach failed to remove dissolved phosphorus (the nutrient of highest concern for fueling algae blooms) and failed to reduce downstream stream bank and bed erosion.
Current regulations guide developers to utilize a system of stormwater reduction practices termed “source control” which include preserving natural features, minimizing impervious surfaces, concentrating structures to disturb as little of the site as possible. They also help utilize features such as infiltration trenches, rain gardens, and bioswales to trap and infiltrate the runoff from most storm events and filter out pollutants. Planning practices to be considered are: preservation of undisturbed areas, preservation of buffers along waterways, reduction of clearing, locating sites in less sensitive areas, using “open space design,” and soil restoration.
Practices for reducing impervious cover are: roadway reduction (length and/or width), sidewalk reduction, driveway reduction, cul-de-sac reduction, building footprint reduction, and parking reduction. Runoff reduction practices listed were: conservation of natural areas, sheet flow to riparian buffers or filter strips, vegetated swales, tree planting or tree boxes, disconnection of roof drains from collection systems, rain gardens, green roofs, porous pavement, stormwater planters, rain barrels, cisterns, and stream daylighting. Lake highlighted that beneficial natural processes function much better in open watercourses, with air and sunshine, than in closed pipes for conveying stormwater. Lake encouraged government officials to incorporate these principles and requirements in to their community comprehensive plans, codes and development review processes.
The Chautauqua Lake Inter Municipal Commission is advocating that all municipalities in the Chautauqua Lake watershed adopt erosion control and site plan review requirements into their municipal codes as first steps in improving storm water management in each community. The IMC with the support of the Chautauqua County Department of Planning & Economic Development has developed model provisions for each community to adapt and adopt. Please contact Don McCord, Senior Planner at 661-8900 for more information on the model provisions. For more information on stormwater management visit: cfpub.epa.gov/npdes/stormwater/swbasicinfo.cfm. The Center for Watershed Protection has much information at www.cwp.org/. The Southern Tier West Regional Planning Board is in the process of developing a demonstration site for stormwater and erosion control practices in Cattaraugus County.
The mission of the CWC is to preserve and enhance the water quality, scenic beauty and ecological health of the lakes, streams and watersheds of the Chautauqua region. The CWC has conserved 718 acres of land across Chautauqua County over the last 20 years. The CWC invites the public to sign up for its e-news at its website and/or “like” the agency on Facebook to receive the most up-to-date information on CWC and lake and watershed-related programs and events. For more information, visit chautauquawatershed.org or call 664-2166.