In the late 1990s, dam inspectors from the Bureau of Reclamation and Northern Water had started to notice changes at Horsetooth Reservoir. A slight increase in the amount of seepage at the reservoir gave notice that the construction work from the 1940s was starting to show its age.

The solution: adding material to the watertight features of the dam, as well as building buttresses downstream of each of the four dams that hold back the reservoir. The catch: to make those improvements, Horsetooth Reservoir would need to be nearly drained. Instead of its high-water mark of about 157,000 acre-feet of storage, the reservoir would be drawn down to 5,000 acre-feet.

Twenty-five years ago this month, the first public look at this project was given, and work would continue through 2001 to add more features to Horsetooth, Soldier, Dixon and Spring Canyon dams to enable them to hold back Colorado-Big Thompson Project water for decades to come.

Inspectors from Northern Water and the Bureau of Reclamation continue to monitor seepage rates at the reservoir to ensure the dam remains safe into the future.