Document Details
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Title |
17.5 km Salmon FSR Culvert Replacement | ||||||||||||
Author |
DWB Forestry Services Ltd. | ||||||||||||
Date |
2009 | ||||||||||||
Abstract |
The previous crossing structure was a 1000mm Corrugated Metal Pile (CMP) with significate road fills above it. Several factors affected the proper functioning of the culvert. The area exhibits evidence of beaver activity immediately upstream. Woody derbis had collected at the intake, partially blocking it. Over time this accumulation could lead to a full blockage of the culvert and ultimately road failure. Root infiltration by nearby trees had caused sections of the existing structure to shift and separate. A large cavity had formed within the road base above the culvert suggesting a probable breach in the CMP. Road fills on the downstream edge were slumping into the stream channel around the outfall causing sedimantation of the stream. The strucutre was installed at a grade of 7.5% creating increased water velocities unsuitable for fish. A perched outlet (35cm) also restricted fish movement through the culvert. Fish sampling was conducted to confirm fish bearing status (DWB Forestry, 2006 and 2007). There were numerous rainbow trout both above and below the crossing. Following a Fish Passage Culvert Inspection (FPCI) in 2006 (DWB Forestry, 2006), the crossing received a high ranking under the FPCI scoring matrix. The CMP was determined to be a full barrier to fish mo vement within the reach and should be eligible for funding pending FIA approval. | ||||||||||||
Report Number |
FIA2009MR090 | ||||||||||||
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