Lake Jennings stores mostly imported water that when filtered becomes drinking water for more than a quarter million people in the East County region. It also serves as a recreational magnet for local residents — fishing, boating, and camping are popular; hiking and bicycling less so.

To get there, exit Interstate 8 at Lake Jennings Park Road, just east of El Cajon. Go north for about 0.3 mile and turn right on Harritt Road, following the signs to Lake Jennings.