|Description:||This historic 1922 diagram depicted a plan for a small municipal Minnesotan water filtration plant. This sketch showed the sand filter located in the bottom of the plant, in detail. Other views of this filtration plant can be seen in PHIL_8645, 8646, 8647, 8648 images.|
This was one of a series of instructional images used by the Minnesota Board of Health, in order to train its state public health workers. The purpose of these images and the accompanying training was focused on protecting water supplies from bacterial contamination due to incorrect disposal of waste, such as sewage, which might foul ground water, rivers, lakes, and streams.