Gross Reservoir Expansion Project
Boulder County, Colorado
The Gross Reservoir Expansion Project raises the existing dam to expand water supply for the Denver metro area. Delivered by Kiewit Corporation and Barnard Construction Co., a joint venture, the project increases storage from approximately 42,000 to about 119,000 acre-feet.
The scope includes raising the dam 131 vertical feet to a final height of 471 feet and increases the crest length to 2,000 feet using a downstream roller-compacted concrete buttress placed to follow the existing dam’s arch shape. Work includes quarry development, aggregate processing, foundation drilling and blasting, excavation and placement of roller-compacted and conventional concrete, along with modifications to outlet works and mechanical systems.
At completion, the dam provides greater flexibility and resiliency for the region’s water system.