Pump houses: a bit of trivia

The city has been constructing a building around its seventh water well. I finally have located the other six, or at least I think I have. Well house Number 1 is next to Iroquois Park.

(This building was appreciated in the Jasper County Interim Report. It was classified as notable. The report states,
"Relatively detailed for a functional building, it was constructed around 1935." The Report liked the powerhouse more--it was classified as outstanding. I need to do a post about it sometime.)
The second well house was the last one I found. It is hiding in the back of Iroquois Park, behind the log cabin and the playground.
The next three are on Bunkum Road, across the street from the new part of Weston Cemetery and from the former trailer court.

With well #4 the city switched from brick to cement block.

I am not sure what the logic was to drilling three wells so close together. If a well has problems, why drill another so close by? Wouldn't you expect it to have problems as well? Or are they drilled to different depths?
Well #6 is on Matheson.