Those Zebra Mussels are both a curse and blessing. Curse because they grow like crazy, forming banks that block traffic and grow inside of piping clogging it all up. Blessing in that they filter water like crazy.
About 20 years ago I went down to Racine Harbor in Lake Michigan. a place that I fished infrequently, but never could see bottom in 10' of water. My last visit, which was 3 years after the prior visit, I could see bottom in 15' of water, a bottom covered with zebra mussels.