Virginia Institute of Marine Science
VIMS Eastern Shore Laboratory Technical Report No. 4
Expansion of poultry house operations and use of litter as a soil amendment in Accomack County Virginia has raised concerns for water quality impacts both seaside and bayside of the Eastern Shore of Virginia (ESVA). This ongoing investigation is examining freshwater stream water quality in Accomack Virginia to identify water quality impairments from poultry operation storm water runoff. Sampling in 2019 followed two inch rainfall events covering 83 streams at road crossings in southern and northern Accomack County. Estimates of land cover in the drainages for these streams were used to determine correlations between stream water nutrient levels and the presence and distance of poultry operations, agricultural fields, residential housing, forest, and swamps. No overall effect of poultry operations or other coverage variables on stream nutrient levels could be detected.
Individual streamsheds for stations that exceeded the range of potential observable effects levels (OELs), estimated for Virginia streams, were examined more closely for potential loading sources. For total nitrogen, 27.7% of all stations exceeded the lower OEL limit (2.6 mg/L), with 6 of the 23 stations having poultry operation upstream of the sampling point. The upper OEL limit (3.66 mg/L) was exceeded in samples from 13.3% of all stations, with poultry operation in 3 of those 11 streamsheds. For total phosphorous, 12 stations (14.5% of the total) exceeded the lower OEL threshold (0.25 mg/L) with 2 of the twelve stations having poultry operations upstream. The upper OEL limit (0.284 mg/L) was exceeded at 9 stations, 2 of which had poultry operations in the drainage area.
Stream water quality will be assessed again in 2020, targeting both storm events and dry periods, and analysis will target greater resolution in nitrogen species (ammonia, nitrite + nitrate, total nitrogen) and phosphorous (dissolved orthophosphate, total phosphorous) in the water samples.
Snyder, R. A., & Ross, P. G. (2020) Water quality in Accomack County Freshwater Streams. VIMS Eastern Shore Laboratory Technical Report No. 4. Virginia Institute of Marine Science, William & Mary. 10.25773/6aq5-nm56