Is dam seepage cause for alarm? — The Pueblo Chieftain

Clear Creek Dam via Colorado Guy
Clear Creek Dam

From The Pueblo Chieftain (Chris Woodka):

The Pueblo Board of Water Works agreed to hire Black & Veatch Engineering for $130,000 to assess the risk of Clear Creek Dam, located in northern Chaffee County. The earthen dam, built on a glacial moraine, has experienced seepage during the past 20 years, creating the occasional need to lower water levels temporarily to fix problems, Steve Anselmo, water resources engineer, told the board. Seepage monitoring has revealed 300-700 gallons per minute at varying exit points.

In 1997, when the downstream face became set, the water level in Clear Creek was lowered and a drain blanket installed and low spots filled in. Additional low spots were filled in 2007, when the water level was lowered to replace the outlet gates.

No unusual problems occurred until 2014, when one flow stopped and a new seepage path was detected.

“The new seepage path created in 2014 has raised the question of how to determine if this seepage event and others that might occur in the future pose a risk to the safety of the dam,” Anselmo said in a memo to the board.

“What actions should be taken to address that risk?”

The Black & Veatch study will look at the probability of a significant event and develop short-term and long-term solutions.

Pueblo Water bought Clear Creek from the Otero Canal Co. in 1954 and in 2004 filed an application in water court that would nearly triple its storage capacity. Clear Creek can now store 11,439 acre-feet of water. A native water right produces a small amount of water, but most of the water in the reservoir is imported from the Western Slope through tunnels and ditches and moved into the reservoir by exchange.

More Pueblo Board of Water Works coverage here.

Leave a Reply