Frost Ranch Bank Stabilization Project
- Project Channel Length: 400 feet
- Completion: May 2014
The Project site is located at 17825 Hanover Road, Fountain, CO, 80817 in southern El Paso County approximately 1.0 mile east of Interstate 25 and 0.3 miles south of Hanover Road on the Frost Ranch. The Project lies along an eroding bendway where Fountain Creek migrated into a bank with little riparian vegetation, which led to accelerated soil erosion. Over the years, the bank erosion caused property loss and increased sediment supply. Eliminating erosion along the bank protects viable agricultural land, reduces sediment supply downstream, and improves both terrestrial and aquatic habitat.
The lack of vegetation along approximately 400 feet of the bank allowed the soil to be readily removed during high flow events. Consequently, the landowner experienced flood damage and bank erosion that caused loss of property, damage to fences, loss of productivity, and loss of habitat and vegetation. Since 1999, the bank has migrated as much as 70 feet at one point.
As a result of the bank erosion, the creek became over widened from the stable Fountain Creek reference width of about 160 feet to more than 200 feet. Near the lower end of the Project, the bank “scalloped” out and created severe secondary currents (eddy) that would have aggravated future erosion. Using an estimate of erosion based on a bank erosion hazard index and near bank stress, it was predicted that routine (non-flood) erosion increased from about 0.1 tons/foot/year to nearly 1 tons/foot/year. Along the 400-foot Project reach that equates to an increase from 40 tons/year to 400 tons/year, or a ten-fold increase. The over widening and increased sediment supply caused downstream deposition which, if allowed to continue, would in-turn aggravate bank erosion.