Building a Dam

Fir logs up to 30 feet in length formed the base for the diversion dam. Although it was built in the winter when the river was sluggish, pumps were needed to divert the flow around the construction site. The dam is used to fill the tunnel when the water is low in the river. Concrete was poured in the fall of 1912 to complete the opening of the tunnel portal. The tunnel can carry 1,100 cubic feet per second, equal to 495,000 gallons (1,871,100 liters) every minute. Most of the portal is below the waterline.

Crawford, Colorado · United States