|Description:||This historic diagram, which had been digitally enhanced, depicted an example of an unsatisfactory plumbing configuration for a typical residence. This cross-section of the building, revealing its water intake and outflow points, showed a hazardous cross-connection between water supplies, and the sewage disposal system. The light-green lines represented water intake. The red lines represented waste water disposal lines running into the building drain at the bottom of the diagram.|
Published in 1934, this was one of a series of instructional drawings used by the Minnesota Board of Health to train the state's public health workers. The purpose of this and other like images, and the training was focused on protecting potable water supplies from bacterial contamination.