Crooked Arroyo CA-4 Detention Reservoir is a reservoir located in Otero County, Colorado. It appears on the Toonerville NE USGS 7.5-minute topographic quadrangle. The elevation at this location is approximately 4,001.26 feet (1,219.58 m) above sea level. The nearest populated place is Gilpin, approximately 4.5 miles to the WSW.