On Jun. 26, 1908, a typhoid fever epidemic struck Mankato, Minnesota with 5,000-6,000 cases of diarrhea reported between June 26 and July 4. Unusually high rainfall earlier in the month had caused the Minnesota river to reach its highest level since 1881 overwhelming the city’s sewer system.

On June 27, newspapers reported the source of the disease outbreak had been identified and citizens were advise to boil their water before using.

The Minnesota Board of Health produced an illustration of the Mankato sewer system in 1908 to help train its state public health workers. The design of the city’s system was determined to be the cause of the epidemic. The focus of the image was on protecting water supplies from bacterial contamination due to incorrect disposal of waste, which might foul ground water, rivers, lakes, and streams.