Atrazine - The Maximum Contaminant Level (MCL) of atrazine in any class “C” water is 3 parts per billion (ppb). A class “C” water is any raw water source that may be used to supply potable drinking water.

Ammonia Nitrogen as N - The allowable standard for ammonia nitrogen varies widely depending on water temperature, water pH, water classification, and the presence or absence of early life stages of aquatic organisms.

E. coli - The Geometric Mean shall not exceed 126 colony forming units (CFU) per 100 mL of Escherichia coli in any waters classified as class “A1” primary recreational use or class “A3” children’s recreational use. The sample maximum for class “A1” and “A3” waters shall not exceed 235 CFU/100 mL. In class “A2” secondary recreational use waters, the Geometric Mean shall not exceed 630 CFU/100 mL and the sample maximum shall not exceed 2880 CFU/100 mL. Note: The E. coli standards do not apply from November 16th to March 14th.

Membrane Fecal Coliform Bacteria – The concentration of fecal coliform bacteria shall be less than 1 CFU/100 mL in any class “C” water.

Nitrate + Nitrite as N - The concentration of Nitrate+Nitrite should not exceed 10 mg/L in any class “C” water.

Total Phosphate as P - The state of Iowa has not set and acceptable water quality standard for total phosphate levels in surface or drinking water.

Turbidity - The turbidity of the receiving water shall not be increased by more than 25 Nephelometric turbidity units (NTU) by any point source discharge.