Snook,
I am too young to remember the 70s but I do remember the 80s and I agree that the water is worse today than it was then. Trust me the ag industry is very aware of the spotlight being shone upon them in regard to water quality. Most of my customers want to be and are good stewards of their land and practices. It is hard to pass farms on to new generations without being good stewards.
Here is a little food for thought as I end this post. I farm 100 acres and apply 200#/acre of nitrogen/phosphourous which equals 1 ton on 100 acres. My water has to go through the ground to the ditch to the stream to the maumee river to lake erie. Sediment falls to the bottom the entire way which is about 50 miles from the lake. Now lets say I own a house in a subdivision. I apply 2 50# bags of fertilizer to my 1/12th of an acre grass yard, 1 bag of nitrogen and 1 bag of phosphourus, throughout the entire year. That is 100# on 1/12th of an acre. 100 times 12 equals 1200 lbs/ac equivalent whish is 2/3rds of a ton. Now the water in my subdivision hits the stormsewer system, the system is overwhelmed, and I live 20 miles from the lake. Now times this by the number of homes in close proximity to each other in an urban setting. THe numbers are astronomical. As I have said before I am not defending agriculture, but we are not as large a contributor to this issue as we get credit for. Everyone has a share in the problem, but somtimes you need to put things in perspective. Good luck in 2012 fishing!!