Maine Healthy Beaches Program
Stormwater runoff can negatively impact recreational water quality. When rain falls on the land, the water washes over the surface picking up bacterial pollutants from malfunctioning septic systems, wildlife, pet waste, etc. and are transported to the coastal surf-zone by runoff directly to the beach or via freshwater inputs such as rivers, streams and storm drains. The lag time (24-30 hrs) in obtaining fecal indicator bacteria results may pose a public health risk; therefore, some states have implemented an automatic precautionary rainfall advisory system where particularly high risk beaches are closed when rainfall exceeds predetermined levels which can vary widely (0.1-1in.) depending on the state, beach, and local conditions (Massachusetts, New Jersey, California, and Ohio1).
Sims, M. and Kaczor, K, "A Preliminary Examination of the Effects of Local Precipitation on Beach Water Quality at 3 Coastal Beaches in Maine" (2014). Maine Sea Grant Publications. 44.
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