Tetayut (Sandhill/Shady) Creek Restoration: Removing barriers to fish passage at the Pat Bay Highway (17) in Central Saanich, BC

  • Andrew Anderson University of Victoria


Tetayut (Sandhill/Shady) Creek is located in Central Saanich, BC where habitat connectivity issues have existed for decades as a result of a 54 m long concrete culvert under the Patricia Bay highway (Highway 17). The BC Ministry of Transportation and Infrastructure owned culvert is located approximately 2.2 km upstream of the Juan de Fuca Strait where it conveys water onto land owned by the Saanich Historical Artifacts Society. High velocity flows through the culvert have resulted in channel degradation and scour leading to a perched outlet that prevents the biologically important and culturally valued fish species in the Creek from accessing approximately 2.0 km of upstream aquatic habitat. Removal of this barrier required an understanding of the watershed processes as well as the expected discharges during periods of drought and flooding to evaluate the effectiveness of tailwater control modifications. Through careful data collection and desktop modelling it was determined that instream restoration works would promote fish passage while having little to no impact on the upstream hydraulics of the culvert. Co-operation with the Peninsula Streams Society was critical in the delivery of a timely and cost effective solution that lead to the construction of two Newbury-style rock riffles that eliminated the perched culvert. A monitoring program is planned to determine if the upstream habitat sees recruitment of native salmonids over the next five years.
Technical Papers