Big Creek Lake IA 04-UDM-1242

Assessment Comments

Basis for Assessment

Continued to assess support of the Class A primary contact recreation and Class B(WW) aqatic life uses as FST.   Fish consumption uses remain assessed as FS based on results of the 1994 fish tissue (i.e., RAFT) sampling (see above).   In July and August 1997, DNR conducted a special study of bacterial levels in the lake in response to high levels of fecal coliform bacteria at the lake's swimming beach.   Sampling was conducted at 18 location including the beach, mid-lake, and in tributaries to the lake.   Study results showed that (1) levels of fecal coliform bateria at the beach were below the state Class A WQ criterion of 200 fecal coliforms / 100 ml, (2) levels of bacteria in lake tributaries were relatively high but were not the sources of bacteria seen at the beach, (3) mid-lake levels of bacteria were extremely low, (4) the highest levels of bacteria at the beach were at the ends of the beach that are used by a resident population of Canada geese, and (5) the most likely source of the fecal coliform bacteria at the beach is goose droppings.   A report that summarizes this sampling was prepared.   The proposed USDA swine research facility was not constructed in the Big Creek Lake watershed.   The March/April 1998 Iowa Conservationist note that Big Creek Lake provide good angling opportunities for bluegill, largemouth bass, channel catfish, and crappie.