Chicago's River

The Chicago's River I believe plays a significant role in Chicago. It winds right through the city and gives it a natural feel. I went to Northside College Prep for high school, and the river is right in the backyard of the school. I always had wondered if the water is even drinkable, but now, I highly doubt that's a good decision. I knew some of my friends had a meeting by the river to see who could swim across the river and back the fastest. I don't think any of them had any side effects afterwards, so it won't kill you, but still, the water isn't all that clear.
I read a Red Eye article about fish in the river. Apparently, you can eat the fish that lives in the river, but be aware of how much you consume. Most of them are contaminated with small amount of mercury and other chemicals.