With respect to territory outside its corporate limits which is not held by it for reservoir purposes but which territory is within the watershed that feeds a reservoir of the authority, the authority may, by ordinance, prevent pollution of waters which feed its reservoir for a distance of 5 miles upstream from the headwaters of its reservoir and may abate any cause of pollution within that area as a nuisance.

(from Ch. 111 2/3, par. 249)

(Source: Laws 1957, p. 1599.)