A Middle Fork Mystery With No Dam Solution

—This post is a follow up to A Mysterious Discharge On The Middle Fork

Two weeks ago, we posted a story about a mysterious discharge on the Middle Fork brought to our attention by some canoers. Following that story, some hikers reached out to PRN to corroborate the report. They were hiking in the area that day and noticed the same tributary flowing extremely fast and milky white. They followed the tributary upstream to a junction where two smaller tributaries meet to form the one that flows into the Middle Fork. The tributary to the east flowed fast and full of sediment while the tributary to the west was just a trickle.

This junction is just a half mile downstream from Dynegy’s cooling lake dam, and the tributary to the east that flowed full is the one that leads to the dam. The simplest answer is often the right one. There was no rain on April 25th. On that dry day, what else could have supplied somewhere between 10-20 million gallons of water in the half mile between this junction and the dam?

I am not sure we will get a satisfying answer to this conundrum. Illinois EPA has said that they will meet with a Dynegy representative and inspect the dam. Hopefully, this exchange will result in some satisfying answers.

This mysterious discharge gives us reasons to worry. The hikers described it as milky white – quite different from the look of a river filled with typical sediment runoff. There are any number of possible explanations for the white color, some more dangerous than others. Even if this discharge was completely harmless, what is immediately concerning is that we still don’t know what happened. We will keep you updated if and when we learn more.

Thanks to the hikers and canoers who saw something that looked off and decided to share it with us.