IMPERIAL RESERVOIR. Imperial Reservoir is four miles south of Grandfalls and just south of the Pecos River in northern Pecos County (at 31°16' N, 102°51' W). It is bordered by Farm Road 2593 on the north and east and State Highway 18 on the west. The reservoir was constructed on the Pecos River around 1912 to provide irrigation water to the Imperial Canal and to promote land sales. It covers approximately 1,530 surface acres and has a capacity of 8,500 acre-feet. Since 1955 the reservoir has been operated for recreational use by the Imperial Volunteer Fire Department. A dwindling water supply in recent years has produced erratic levels in the reservoir.