Uncovering the Hidden Beauty of Cutoff Creek; Rebuilding Bridges & Restoring Rivers
By: Lili-Maude Craig
Cutoff Creek during 2021 sampling efforts
Cutoff Creek is a small stream southwest of Rocky Mountain House, Alberta. Its flows originate from alpine sources in the front ranges of the Rocky Mountains and groundwater exchange from the adjacent Clearwater River floodplain. These consistent sources provide flow with exceptional clarity, which meanders through a picturesque meadow with a backdrop of lush foothills and snow-capped mountains before entering the Clearwater River. Additionally, a trail system that runs along the creek takes you deep into the backcountry of Banff National Park and Ya Ha Tinda Ranch. It isn’t hard to see why this area is popular for motorized recreation! However, these activities without properly designed watercourse crossings can negatively impact the aquatic ecosystem.
Cutoff Creek is home to a threatened population of Bull Trout, Alberta’s provincial fish. Two off-highway vehicle (OHV) fords [4], which are unofficial river crossings and seven livestock crossings in a section of the creek negatively impacted critical habitat for this species. These redundant stream crossings had severe erosion [2] issues, resulting in the alteration of the natural stream width, degradation [1] of riparian health and bank stability, and the chronic delivery of fine sediment.
Aerial photo of project area showing both OHV fords with several livestock crossings in between.
The input of excess fine sediments can reduce the spawning success of Bull Trout. Sedimentation alters the streambed, making it less suitable for nest making, also known as redds [5] and it can also coat eggs, limiting their oxygen intake and threatening their survival. Cutoff Creek has been identified as an important waterbody for fall spawning salmonids [6], with recent observations of redds, spawning activity, and even juvenile Bull Trout. These observations led Trout Unlimited Canada to pursue opportunities to restore aquatic health and establish a more sustainable stream crossing at this location.
In 2021-22, TUC was awarded a grant from Alberta Forestry, Parks and Tourism to improve recreational trails in relation to aquatic habitat in the upper North Saskatchewan and Red Deer River watersheds. TUC suggested rehabilitation work at Cutoff Creek would be a good candidate for the funds. Subsequently, Alberta Forestry, Parks & Tourism identified an opportunity for a partnership between TUC, Alberta Forestry, Parks & Tourism, and Sundre Forest Products to install a permanent bridge to facilitate future industrial and ongoing recreational use while eliminating these point sources of sedimentation.
In the fall of 2022, a 40-foot industrial bridge was installed, the fords were decommissioned, and damaged banks were rehabilitated using bioengineering, including soil wraps [7] and tree revetments [8]. Riprap [3] was strategically placed on the crossing approaches of one of the fords to block continued OHV use while maintaining livestock passage. TUC is scheduled to revisit the site on May 24th to plant live willow stakes and distribute woody debris along the restored banks.
40-foot industrial bridge was installed over Cutoff Creek.
OHV “Ford 1” prior to closure and reclamation.
OHV “Ford 1” after closure and reclamation.
[1] Degradation: an unintentional decline in quality [2] Erosion: when natural forces like wind, water, and ice gradually wear away and move soil or rock from one place to another. [3] Riprap: layer of large rocks that are put on slopes or near rivers to stop soil or infrastructure from being washed away by water. It helps to slow down the water’s movement and prevent erosion. [4] Fords: Unofficial River crossing [5] Redds: Nest making [6] Salmonids: any of a family (Salmonidae) of elongate bony fishes (such as a salmon or trout) that have the last three vertebrae upturned. [7] Soil wraps: used to separate gravel and soil backfill in a trench, allowing the gravel to remain porous and the soil to stay firm and intact [8] Tree revetments: the placement of native hardwood timber on a riverbank with the objective of preventing bank erosion.
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