I don't know your expereinces but it seems during the summer we can only catch smaller fish. I e-mailed Heath the local DNR office about the lake. He sent this back.
On these larger riverine flowages that have a larger river system coming into them many of the adult fish run up the river systems in the spring to spawn and a good portion of those fish stay in the river until fall and then return back to the flowage to overwinter.
There are still some adult fish in the lake but a lot of times a good number of those fish are still in the river systems during the summer angling season. We see a similar situation on the flowages such as Tainter Lake on the Red Cedar system and Lake Altoona and Lake Eau Claire on the Chippewa River.
The flowages are many times good nursery areas for juvenile fish 12 inchers or so and that’s why you catch a lot in the summer but probably do not get many larger fish at that time of the year.
I’d try fishing the upper end of the flowage below HWY D for the first couple of miles right away in the spring and summer or even take a canoe trip on the Chippewa or Flambeau and take out at D in the summer. There is great smallmouth fishing on these stretches too. Those fish should also start to filter down to the lake in the fall and if you’re up their at that time look to find them coming back down to the flowage. We also found some larger fish in Pine and Cranberry Lakes during our surveys but they were likely feeding and in post spawn mode. You could try those areas too. Those areas are also some of the better crappie spots and if you can’t find walleye you should hopefully find some crappie.