You are allowed to camp in the general area. The general restrictions are that you must be at least 200' away from any water source. I just checked the forest service website and I could not find any more specific restrictions listed for that lake. I'm not sure about weekends, but weekdays, the parking lot is pretty empty.
"Got tight last night on absinthe and did knife tricks. Great success shooting the knife into the piano. The woodworms are so bad and eat hell out of all furniture that you can always claim the woodworms did it."