Journal of Student Research 2018

Urban Photsphorus Runoff and Loading to Half Moon Lake, Wisconsin

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By comparison, the flow-weighted summer mean SRP concentration was substantially higher at > 0.04 mg/L in 1999 but much lower in all post BMP years (Fig. 7). Although linear relationships between mean total P and SRP versus precipitation were weak for post-BMP years, concentrations tended to be lower during post-BMP years compared to 1999 under similar mean summer precipitation conditions (Fig. 8) Total P and SRP loading were also lower during post-BMP years compared to 1999 (Fig. 9) Figure 8. A comparison of mean daily flow, mean event total phosphorus (P) concentration, soluble reactive P (SRP) concentration, total P load, and SRP load versus summer precipitation. Red circle indicates the pre-BMP year 1999 while blue circles denote post-BMP years. Regression analysis was conducted on post-BMP means. 1999 was an outlier.