Excess nutrient input is probably the biggest remaining pollution problem in the United States right now -- most of the more noxious and dangerous chemicals and substances have been pretty well (with some exceptions) cleaned up. But improving stormwater runoff and wastewater treatment is difficult and expensive.
I agree, I've done some work with the CSO (combined sewer overflow) problems in the Great Lakes region. Many communities still have these antiquated waste water treatment plants that discharge untreated water directly into lakes, streams, etc. after rain events. Instead of separating storm and sewer water, they often take the bandaid approach of increasing the plants water retention capacity. There are hundreds of communities that aren't in compliance with the EPA's NPDES (National Pollution Discharge Elimination System) permiting system. At least around here communities don't seem to care as the polluted water flows into surrounding communities, eventually ending up in Lake Michigan. A people wonder why the beaches are closed due to contamination.
Excess nutrient input is probably the biggest remaining pollution problem in the United States right now
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Considering all of today's triumphant technology, surely there must be a way to convert excess nutrient input to a new form of breathtaking breakfast cereal !!! ;-))