This approach has proven successful at monitoring bacteria in the food industry, and Whitman is adapting it for use on lake water. But some major obstacles remain, not the least of which is finding the best antibodies to tag the E. coli. In addition to finding new tests for E. coli, scientists are also working on ways to predict surges in the level of bacteria before they occur. Efforts in the Chicago area focus on the 63rd Street Beach, which closed 22 times last summer, nearly three times the average for other area beaches. The basic strategy used at the 63rd Street Beach is to sample the water at two different points along each of five lines that radiate out from a single spot on the shore, like spokes on a wheel.
Researchers also test the waters at the lagoon mouth, harbor mouth, and break walls.
The concentration of bacteria in each sample is then compared with water currents and weather conditions, including rainfall and wind speed and direction. When the study winds down in September, researchers hope to have gathered enough data to begin to see patterns, and any correlations observed between E. coli levels and the other factors measured will be used to predict future surges in the level of bacteria. Although this sounds simple enough, predicting levels of E. coli is actually a tricky business. Rain can raise bacteria levels when storm-water runoff washes sewage into the lake. But a lack of rain is also problematic, causing lake levels to fall and water temperatures to rise, providing an ideal breeding ground for E. coli.