Worry over possible flooding in Utah County hasn't exactly contributed to sales of antacid tablets during the past couple of years.
But county commissioners say they won't rest easy until certain safety concerns are addressed at the Thistle landslide site.The county developed a $375,000 plan last year to address safety concerns but has been stymied from lack of funding. On Wednesday, the commission decided to request $180,000 from the Disaster Relief Board to match another $180,000 in Department of Public Safety funds.
The public safety contribution is from money, provided by the Denver and Rio Grande Railroad, allocated to keep clean a grating covering the Thistle tunnel entrance.
Commissioners fear future flooding could plug the tunnel, which was built to drain a lake created by a large mudslide in 1983. The slide blocked the Spanish Fork River, creating a natural dam.
Engineers and county officials believe that debris could plug the drain and lead to another buildup of water behind the landslide dam, causing the dam to break.
Commission Chairman Malcolm Beck said he feels good about the county's chances of getting additional needed funding from the Disaster Relief Board. He said the commission has hesitated going to the State Legislature because of tight budgets in recent years.
"If we get the money, we'll go ahead and begin," Beck said. "We'd like to do it right now, or during the winter. It's best when the water is low. When we get the spring runoff, we can't work down there."
In addition to $204,000 needed to build the debris basin, the project will include construction of a control structure at a cost of $90,000. Another $36,000 is needed to purchase land that will be inundated by the basin, and an additional $10,000 will be used to build a dike to protect adjacent land.
The control structure and debris basin will provide better control of debris and silt, and gates will be installed in the structure to stop water flowing into the tunnel so workers can repair the tunnel floor when needed.
The county already has paid out $15,000 in preliminary engineering costs, but another $15,000 is needed for construction engineering.
The plan addresses all concerns except what county officials call the "maximum-probable flood" at the site. Preparations for such a flood are still pending.
Despite the cost of the project, commissioners believe the debris-control structure and basin will save money in the long run by providing better control of Spanish Fork River runoff and preventing improvements along the river's banks from being washed away during high runoff.