It is a huge, shallow lake with an average depth of about 4 feet. Deepest hole is maybe 7-8 feet. If the wind is blowing much above 10 mph the lake gets very very rough. There is a decent ramp and a nice campground at Pettigrew State Park on the North side of the lake.
Water can be crystal clear on calm days when the bottom is not stirred up. Rumor has it there are some huge bass in the lake, although I have not caught anything over 2 pounds. The fish tend to hold in the tree line, and in the lily pads. A lot of people fly fish and wade fish, especially on the South side of the lake. Conman’s campground is on the South side, and I believe the owner is widely recognized as the Phelps Lake expert so you might get some advice there.