Retrofitting existing stormwater management practices with sustainable best management practices (BMPs) such as rain gardens, pervious pavement, rain barrels and water quality devices offers many benefits. These benefits include pollutant reduction, reduced stream channel erosion and reduced water treatment costs to name just a few. Upon receiving the Lake Erie Protection Fund Small Grant the Toledo Metropolitan Area Council of Governments (TMACOG) in partnership with Lucas Soil and Water Conservation District (LSWCD) identified locations within the Swan Creek watershed that would be best suited for stormwater retrofits. The need for alternative stormwater practices in the Swan Creek study area was made clear by analysis of the Ohio EPA 2010 TMDL report, which identified sedimentation/siltation and accompanying nutrients as major causes of water quality impairments. The sources of these impairments are directly related to urban and rural land uses and include stormwater and agricultural runoff and habitat degradation.
The project team used geographic information systems (GIS) analysis and extensive field surveys to identify 87 sites in the study area that could best impact water quality by retrofitting existing stormwater practices with more sustainable BMPs. This was accomplished by ranking sites based on several criteria including the volume of water and paved surface area treated by the BMP retrofit, cost of the retrofit, the ability of construction equipment to access the site, and expected maintenance requirements. The current state of water quality impairments, landowner cooperation, potential for educational opportunities and the cost of the land required for implementation were also considered in the analysis. The project team reviewed the 87 sites and identified specific BMPs (e.g., rain gardens and pervious pavement) that could be applied to each of these sites. In all, 14 locations were identified as having the highest potential for retrofitting existing practices with BMPs.
The outcome of the project was a GIS-based tool for stormwater planners in the Swan Creek watershed. This product can be used in combination with existing stormwater plans to help managers pinpoint and prioritize areas for stormwater improvements. The dataset, which is compatible with Google Earth, provides users with information regarding site accessibility and the ability to maintain a suggested BMP in the context of the larger landscape. Additionally, landowners can use the database to view potential BMPs on their properties that can be used to receive non-residential stormwater credits.
Center for Watershed Protection. Urban Subwatershed Restoration Series, Manual No. 3:Urban
Stormwater Retrofit Practices, Version 1.0. August, 2007.
Cuyahoga Soil and Water Conservation District. Targeting Storm Water Retrofits
to Improve Urban Streams. April 27, 2010.
Ohio Environmental Protection Agency, Division of Surface Water. Total Maximum Daily Loads
for the Swan Creek Watershed: Final Report. October 9, 2009.
Toledo Metropolitan Area Council of Governments and Lucas Soil and Water Conservation
District. Swan Creek Watershed Balanced Growth Plan, Final Report of the Swan Creek Watershed Pilot Project. June 2009.