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Little Topashaw Creek - Nutrient TMDL's - Methods
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  • Low stream flow water samples were collected monthly for 2-7 consecutive days

  • Storm event water samples were collected for 24 consecutive hours

  • Nutrient parameters measured using standard methods (APHA 1998) included Total orthophosphate (T PO4), Ammonia-N (NH4-N), Nitrate-N (NO3-N), Nitrite-N (NO2-N), Total Kjeldahl Nitrogen (TKN), Total nitrogen, and Chlorophyll a.

Isco samplers

  • Nutrient values were compared with:

    1) Proposed USEPA freshwater nutrient criteria for ecoregion IX (rivers/streams)

      • Total orthophosphate (mg/L) 0.03656
      • Total nitrogen (mg/L) 0.69
      • Chlorophyll a (mg/L) 0.93

    2)USEPA(1986) freshwater quality criteria guidelines

      • Ammonia-N (NH4-N mg/L) 1.0
      • Nitrate-N (NO3-N mg/L) 10.0
      • Nitrite-N (NO2-N mg/L) 0.06
      • Total Kjeldahl nitrogen (TKN) No Reported Values