Lake Elkhorn is stocked each year with few hundred small Bass, and you can find some 2-3 lbers in there. The biggest I caught in there was 4.2lb, but mostly you are pulling 1-2lbers.
Rocky Gorge is managed by WSSC, and I have added a link to their website. You need to buy another permit to fish there, and a single day permit will cost $6.00. There is very limited shore fishing available, so I suggest get a kayak or a small row boat. I fished Rocky Gorge today, and got a 14lb bag.
http://www.wsscwater.com/home/jsp/content/watershed.faces#wheretopurchase