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Little Topashaw Creek - Nutrient TMDL's - Results
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Chart of Total Kjedahl Nitrogen
Nutrient loads during storm events were commonly greater than during low stream flow conditions due to runoff from nearby agricultural fields. Peaks in nitrogen and phosphorus concentrations during the May 22, 2001 storm event are associated with applications of fertilizer at the end of April and beginning of May 2001.

Both total orthophosphate and chlorophyll a concentrations consistently and significantly exceeded USEPA ecoregion IX criteria even during low flows. 

Ammonia and nitrate concentrations never exceeded 1986 USEPA water quality criteria guidelines during low flow and rarely exceeded criteria during storm events. Although individual nitrogen species were not shown to exceed these criteria, total nitrogen frequently exceeded (88%) the USEPA ecoregion IX recommended concentration of 0.69 mg/L during storm events and often exceeded (57%) the recommended concentration during low stream flow.
   

Corn growing adjacent to study reach