Built in 1896 on the Little Colorado River, River Reservoir is the largest and deepest of a trio of lakes collectively known as the Greer Lakes. Drained since 2004 because of safety issues, the dam at River Reservoir was repaired in 2005. Like the other two Greer Lakes, it has new amenities. River Reservoir is located at 8,220 feet (2,510 m) on the Apache-Sitgreaves National Forests.