Two-and-a-half miles south of the main dam at Chimney Hollow sits the saddle dam, which is often a forgotten, but major, component of the project. Completion of the saddle dam will increase the reservoir’s capacity by about 30 percent.  

Unlike the main dam, the saddle dam will be a clay-core rockfill dam, similar to those at Carter Lake and Horsetooth Reservoir. It will be 40 feet tall and contain approximately 100,000 cubic yards of rockfill and 30,000 cubic yards of clay. It will also include a double-row grout curtain extending approximately 70-feet below the dam to reduce seepage through the foundation.  

Crews have been working over the last few weeks to excavate the area and begin pouring dental concrete. Soon, crews will begin to place the concrete grout cap, which will be the stable base for the dam to begin rising. A grout cap and a plinth are essentially the same; however, a plinth is the term used with asphalt-core dams, while a grout cap is used in reference to clay-core dams.