The Painted Rock Dam is an earthfill embankment dam located west of Gila Bend, Arizona. It is primarily used for flood control purposes. Description The Painted Rock Dam was constructed during a 3-year period from 1957–1960 by the United States Army Corps of Engineers to help control seasonal floods on the lower reaches of the Gila River. The river had no significant impediments between the Colorado River and the Coolidge Dam hundreds of miles upstream. In this stretch the river receives several tributaries, including the Hassayampa, Agua Fria rivers, and most importantly the Salt River and its major tributary, the Verde River. Due to a relatively large watershed of , more than half of which is unregulated, the flood threat to small farming communities downstream on the Gila River is large, and seasonal flooding of these areas prior to the construction of the dam was significant. The area surrounding the dam has also hosted a number of historical events. The Butterfield Overland Mail route passed through the area, as did the path followed by the Mormon Battalion. Evidence of both can be found, as well as the expedition of Juan Bautista De Anza in 1774. Inscriptions made by these groups can be found in various sites in the region. Near the dam site, there is also a campground maintained by the Bureau of Land Management that showcases a number of prehistoric petroglyphs, indicating human involvement in the region long predating Western influence. It is from the Painted Rock Petroglyph Site that the area and the dam get their names. The lake and reservoir are dry as of August 2009 and are closed to the public due to contamination of pesticide run off. This is in stark contrast to the level of upkeep during the 1990s. The state was forced to abandon the campground and the area is now marked as "NO TRESPASSING". No hunting, hiking, or camping is allowed. The Army Corps of Engineers now maintains the property. Painted Rock Reservoir The Painted Rock Reservoir is an artificial reservoir impounded by the Painted Rock Dam. The reservoir, with a maximum storage capacity of , has the potential to be the second largest reservoir completely within the borders of the state of Arizona, but because the Gila River and its main tributary, the Salt River, are generally almost always completely diverted for irrigation and municipal water use for Phoenix, the lake