The dam was completed in 1918 by the Utah Construction Company . It served irrigation canals in the Lost River Valley . In June 1933 , the control tower and diversions were attacked by " unknown persons " using dynamite . At the time , it was suspected that these residents and farmers were desperate for more water during the drought and thought the dam was to blame . The primary dam structure was undamaged . This prompted the owners , the Utah Construction Company , to drop its selling price on the dam , and in 1936 , the town of Mackay purchased it under the Lost River Irrigation District . Since that time , Mackay has hosted an annual barbecue in the fall to celebrate the purchase of the reservoir , which residents fondly call " The Res " . Mackay Reservoir survived the 1983 Borah Peak earthquake , despite extensive damage to the nearby towns of Mackay and Challis
1983 Borah Peak earthquake
1983 Borah Peak earthquake
Mackay Reservoir (Idaho)