The Gross Reservoir Expansion Project entered a new phase this year when workers began building the concrete steps that will raise the height of the dam by 131 feet.
When construction is complete in 2027, Gross Dam will be 471 feet high. The higher dam will nearly triple the storage capacity of Gross Reservoir and add balance and resiliency to our overall water storage system. Reservoirs allow us to capture and store water when it’s available, such as during the spring runoff, for use when it’s needed.
Workers are using roller-compacted concrete to build 118 “steps,” each of them 4 feet high, on the downstream side of the dam, which will change the look of the dam. The original dam had a flat surface on the downstream side. The new, higher dam will look more like the ancient pyramids of Egypt.