Record group 86-121 consists of atlases of water sampling sites (ca. 1932-1938) as compiled by the Michigan Steam Control Commission. During the summers of 1931 and 1932, the Commission took about 2000 water samples in the Great Lake waters controlled by the state in an effort to check on pollution. The atlases show the location of "public bathing beaches, major sources of pollution, [and] waterworks intakes." Following each plan (rendered at a scale of 1:40,000) are sheets that provide analytical data on the finding of various sites. Information includes: date of same, station number, specific location, kind of weather at moment of recording, number of bacteria per c.c. and number of B. Coli per c.c. All Great Lakes are documented. Additional information on this project can be found in series 2 of RG 72-111.
