This is a big problem in the Great Lakes region as well. From our digital orthophotos we can see algal blooms as well as sediment plumes coming from the tributaries. This is going to be a hotbed issue.
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.
The solution to pollution is dilution, right???