There is one reason that I fish power plant lakes over other lakes. There is always a chance that the next bite will be the 10 plus pound fish of a life time. Also catching numbers of big fish is always possible on that "Great Day On The Water". Up here in the Midwest, long cold winters will shorten the growth rate of bass per year in a traditional lake or river. A heated power plant lake will give you growth rates similar to those in the south.
The 1st thing you will notice is that the pattern you have been fishing in your cold water lakes is completely different for the same time of year in a heated lake. While you can usually catch some short fish beating the banks,the keeper fish will be relating to four factors.
The first factor is water temperature. Your keeper fish will be relating to the warmer parts of the water in the fall, winter, and spring. But don't forget the hot water area in the summer,fishing a little deeper and slower will get you some bites since all the other fishermen have headed for colder water.
The second factor to look for when fishing a power plant lake is current. Always look for the current. When the power station kicks in the generators, everything in the lake can change. The bait fish start moving and so do the bass. Your normal techniques for fishing current apply and the current breaks will hold fish ready for an easy meal to get swept by.
The current also will raise our third part of the picture, oxygen levels. I always look to the main lake points when the current kicks up as the fish that have been hard to catch will come to life and become more aggressive. At the same time, fish hiding under a laydown will reposition on top and to one side of the tree. Where you would have to shake a jig forever to get him to bite, now a crankbait bouncing off the tree will attract the bass like he might never get to eat again.
Finally, look for bait fish in the summer, fall, and winter. In the summer, look for bait fish on a break on main lake points. Locate some cover along the break and hold on. In the fall, while looking for bait fish in the back of the coves will get you some fish, don't forget the hot water discharges on the lake. The bait fish will stack up in there so thick it will show up as nothing but black on the depth finder. The big bass like to lay right on the bottom and just eat what the smaller game fish let fall to the bottom. In the winter, I like to find bait fish along the main river channel. I seek out laydowns with a jig and you'll catch enough fish to keep you warm.
Remember when fishing in the winter to get the fish back in the water as soon as possible. Not only are they holding their breath, but now they have gone from 60 to 30 degrees. Brrrrrrr!