The Pond That Should Not Be

I have noticed a particular pond near the Menomonee River.  It's not large, probably less than an acre.  There is an island in it and a large sewage pipe drains into it, probably from Miller Park's lot.  The water is always opaque, not quite like skim milk.  Out of curiosity, I fished it for a little bit one day in December.  I didn't have any strikes, but there is something in there-- something big.

I'm going to fish this pond until I catch what's in there, whether it be carp, catfish or Cthulu.