While the no-discharge goal that Muskie and his allied promoted has yet to be achieved, the 1972 Clean Water Act is credited with leading to improved water quality in rivers, lakes and streams.
In the years since the bill passed, agricultural and urban runoff, in particular, have been greatly reduced.
While many were concerned about the costs to industry and to employment, as Muskie's letter to the editor suggests, the bill did not lead to the dire results some predicted.