Click the link to read the article on the Steamboat Pilot & Today website (Dylan Anderson):
Oak Creek could save “millions” off the projected $14 million price tag for fixes at Sheriff Reservoir after updated engineering on the project showed the town’s water source needs a much smaller spillway than originally thought. While the town previously believed the new spillway needed to be 300 feet wide, the updated work shows it only needs to be about 60 feet wide, according Steve Jamieson, an engineer with W. W. Wheeler that has been consulting for the town on the project. That is still twice the size of the existing spillway…
The recent work resulted from a Comprehensive Dam Safety Evaluation, which looked at ways the dam could fail during normal loading, flood loading and earthquake loading. The highest risk found was due to a gate failure, something that Jamieson said isn’t surprising as the town works to replace the original head gate on the nearly 70-year-old dam. Oak Creek has gone through a bid process for this work twice, but each effort failed to find a contractor the town could afford. A gate failure wouldn’t lead to loss of life, the analysis showed, but it would compromise the town’s water source, making the impact significant. The new risk identified is called a “liquefaction failure,” and it is related of the area’s seismic activity. While noticeable earthquakes are not common in Routt County, they are not unheard of. Since 2000, Routt County has seen approximately two-dozen earthquakes, with the largest being a 3.5 magnitude event about 10 miles northwest of Oak Creek in 2011, according to the U.S. Geological Survey.