At the Yampa Town Board meeting last week, Andi Schaffner with the Bear River Reservoir Company presented plans and cost estimates for a Stillwater Reservoir project that would lead to removal of its storage restriction.

The plan consists of two phases involving installation of a strain and a sand filter to alleviate seepage into the dam’s embankment, the primary concern that led to the storage restriction designation. 

According to Schaffner, Stillwater Reservoir was put under storage restriction in 2018 by the Dam Safety Division of Colorado Fish and Wildlife Resources because of seepage on its left abutment. She described the abutment as being on the left side if one were to walk up from the parking lot to the dam. 

Currently, the town of Yampa owns 112 shares in Stillwater Reservoir, or about 2% of the reservoir. Phase 1 of the project consists of a blanket drain and filter collar and is estimated to cost $730,717. Phase Two of the project will be stabilizing the channel and the removal of the culvert and the flume, at a total estimated cost $209,874. 

Schaffner said that the team at Bear River Reservoir Company has spent hours on engineering and studies at the reservoir in order to determine the best solution for the dam. “We finally opted for the least expensive fix, which is what we’re working on right now,” said Schaffner. 

The project has received a significant amount of grant funding despite higher than anticipated bids, including a $202,000 loan from the Colorado Water Conservation Board. This loan was the primary expected cost for the town of Yampa, and is expected to be approved with an increase to $404,000 ahead of the project’s notice to proceed with the contractor on July 13. The project is expected to be completed by the end of October. 

The Colorado Water Conservation Board loan is 30 years with 1.85% interest, or $3.40 per share per year. For the town of Yampa’s 100 or so shares, this amounts to $381 a year. Schaffner did not expect any more expenses besides an assessment of the shares which amounts to about $5.

“Long story short of it is we picked this option which we have been assured that if we complete this project, the storage restriction will be taken off,” said Schaffner. 

Schaffner said the original proposed project, grout curtains on the dam itself in order to stop the seepage, was projected to cost over five million dollars. Based on her experience with Colorado grant funding, she said there was not enough funding to even come close such a high cost. 

“I guess the elephant in the room is that this project really does not prohibit any seepage. We’re still going to have the same amount of seepage we’ve been having because this project does not control that,” said Schaffner. Yet this project is the most cost effective and realistic project in order for Stillwater Reservoir to have it’s storage restrictions lifted. 

Stillwater Reservoir has a total capacity of 6,088 acre feet, but with a low snow year it is currently storing 1,500 acre feet of water. 

Schaffner also reviewed the town of Yampa’s shares in Gardner Park. The town owns a miniscule percentage of two shares out of 11,000. At the body of water’s fullest, these two shares would amount to 0.11 acre feet of water. Gardner Park is currently 60% full, which means the town of Yampa has about 0.06 acre feet. Schaffner determined that this was not a viable water source for the town to use. 

Gardner Park has now also been reclassified from a modern hazard ban to a high hazard ban, which means it needs to be expected every year. Schaffner said the company is up to date with Gardner Park and that they see minimal seepage. 

One town board member commented on the lack of use for the town’s little shares in Gardner Park. “We’re not paying a great amount of money for [the water shares] now. I would like to see us donate those shares to the Gardner Park Reservoir Company to help offset their evaporation,” they said. “I don’t think we need to be hanging on to the shares.”

Board members said it would be added as an action item for future meetings.