Jessica Sitnik, (Biology) College of William and Mary
Construction of retention ponds is one of the most common best management practices (BMP) for stormwater runoff. Hundreds of ponds have been built to control sediment and nutrients held in the runoff from urban development. The Commonwealth of Virginia has regulations for the retention time and peak flow of these ponds, but no regulated level exists regarding their negative impact on downstream aquatic environments. I determined the structure of macroinvertebrate communities residing upstream and downstream of five retention ponds on the southeastern coastal plain of Virginia. Leaf litter bags containing indigenous leaves were placed in streams for several weeks, then organisms in the bags were sorted and identified to the family level. A total of 12,809 invertebrates representing 32 families were tallied. The dominant taxa in litter bags were chironomids, isopods, and annelid worms. The number and types of macroinvertebrates upstream versus downstream of retention ponds were quite variable, however, so no general conclusion could be made regarding the impact of stormwater retention ponds on community structure in streams.
For additional documentation Jessica Sitnik provided a PowerPoint Presentation entitled "The Effect of Storm Water Retention Ponds on Macroinvertebrate Community Structure" provided here in PDF form.