Mr. Powell. It would have to be supplemented or preceded by sedimentation or screening?
Mr. Waterman. You are speaking of the water itself?
Mr. Powell. Yes.
Mr. Waterman. We feel that filtration of the water supply is necessary, followed by chlorination.
Mr. Tawney. Is this contamination of the waters of these various places due to the sewage which they themselves deposit in the water raw, or is it due to the pollution that is put in above raw, that goes farther out in the stream?
Mr. Waterman. In the case of Ford City, I would say that the sewage of the village itself undoubtedly contaminates an already polluted supply, and the same is true of Trenton, although undoubtedly the pollution which enters the river from the city of Detroit is more or less mitigated before reaching Trenton. At Wyandotte the sewers are all below the water intake, but the sewers from the village of Ford are above and undoubtedly pollute that supply.
Mr. Tawney. How far above?
Mr. Waterman. I would estimate the nearest one was about a mile above the intake, and there are two others within a distance of 2 miles from the intake, both entering directly into the river at the harbor or dock line——
Mr. Tawney. And the intake at Wyandotte is how far out?
Mr. Waterman. The intake at Wyandotte is approximately 150 feet out, so that whatever pollution comes in at this point 1 mile or 2 miles above would probably be diffused that distance from the shore at least, probably more.