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Typical Roof Runoff Quality in Minneapolis and Wisconsin

Typical Roof Runoff Quality in Minneapolis and Wisconsin 
Constituent Minneapolis1 Wisconsin2
E. coli (#/100 mL) 764  
Total Solids (mg/L)   126
Total Solids (mg/L) 10 19
Total Hardness (mg/L)   44
Total Nitrogen (mg/L) 0.421  
Ammonia-N (mg/L) 0.268  
Nitrate-N (mg/L) 0.586  
Total Phosphorus (mg/L) 0.104 0.24
Total Dissolved Phosphorus (mg/L) 0.076 0.11
Soluble Reactive Phosphorus (mg/L) 0.065  
Cadmium (mg/L)   0.0004
Copper (mg/L) 0.0075 0.01
Lead (mg/L) 0.0032 0.01
Zinc (mg/L) 0.101 0.363
1 Arithmetic mean concentrations; Reference: Minneapolis Public Works, City of Minneapolis Neighborhood Rain Barrel Partnership Project, 2008 
2 Highest geometric mean concentration reported; Reference: Roger T. Bannerman and Richard Dodds, Sources of Pollutants in Wisconsin Stormwater, 1992