We have camped many times at the Cholla campgrounds which is on the lake, 3-4 miles West of the dam and bridge. They have hot showers and toilets that flush!!! The best camping spots are close to, and overlook the lake.
On the West end of the bridge, just after the guard rails is the Vineland trail. The first part is a slough with a rise of 800 feet in 1 mile, but once your on the ridge it's a great hike. If you head South just before you hike up to the ridge, you can see the dam and the lake. It's a beautiful but be careful, it's steep and that first step is a bad one.
On the East side of the bridge about 300 yards past the intersection of 88 and 188 is another trail. You can see the gate from the road. It's called something cemetery trail and heads due East as I recall. Have fun!
Mother nature seems to like humans, and not just because they taste like chicken