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· Super Moderator
6,318 Posts
Discussion Starter · #1 ·
With Fall coming on strong and the close a little over a month away I wonder if anyone had been out lately. The shad hatch should start diminishing and making way for some good fishing over the next few weeks. Jason, I know you have previously ventured out their on a consistent basis. I may take the boat out next week it things are looking up. On a side note, I here they raised the water level to accomodate a project by Midwest Generation which is making getting under the bridge to the North side difficult. I have even heard stories of guys in bigger boats pulling their plugs and letting their hulls take water to get low enough for the clearance. Gotta love that dedication :p

· Registered
594 Posts
Jason, i think you are right.

When hot water was being discharged, that lake was in a state of warmth.
Now without that heasted water, it reverted back to a natural state of warm/cool.

· Premium Member
2,617 Posts
First of all, welcome to WCF blumpie!!


One reason you sometimes have a hard time catching fish this time of year might be fall turn-over. On most lakes there is a phenomenon that happens each fall as the water cools. During hot summer weather the top of the lake warms but the lower areas stay cooler. An area called the thermocline separates the two.

At the surface of a lake the water will be very warm and stays warm down to a certain level. For example, the surface might be in the 90 degree range in September while 15 feet deep it is 80 degrees. From 15 to 20 feet the temperature will drop fast - several degrees in a few feet, from 80 to 60 degrees in this example.

Below 20 feet the water might be as cool as 60 degrees and it will stay that cool all summer.

Unfortunately for the fish, this deep, cool water is very low in oxygen. Fish can not live long in it. A good depthfinder will show the thermocline because algae and protoplankton will form a layer there, and the deeper, colder water is much more dense.

Fish are limited to spending most of their time in the upper levels of the lake. But as the surface cools in the fall, the top layer will suddenly mix with the lower layer, breaking the thermocline, when the surface layers get as cold as the lower layers.

When this happens the stale deeper water mixes with the upper levels, and the whole lake may take on a murky look and have a bad smell. For a few days the fish don't feed much. Then, after things settle down, the fish can scatter. After turn-over the whole lake has good oxygen content and fish can move anywhere. They are hard to pattern because they roam a lot for a few weeks before setting up on deeper winter structure.
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