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Culvert Project. Fish Passage – Moving from a focused culvert evaluation to FREP. Richard Thompson Senior Habitat Biologist Ministry of Environment. Background Overview of Process Field Methods Overview Detailed FREP – What’s next. BACKGROUND
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Culvert Project Fish Passage – Moving from a focused culvert evaluation to FREP. Richard Thompson Senior Habitat Biologist Ministry of Environment
Background • Overview of Process • Field Methods • Overview • Detailed • FREP – What’s next.
BACKGROUND • “Poor culvert design and location can be ranked among the most devastating fish constraints to be found in the Province. The correction of which is vital to the maintenance of present spawning areas and the rehabilitation of areas no longer accessible because of past culvert failures. Until adequate corrective measures are taken, fish populations will continue to be detrimentally affected, and the province will be burdened with the difficult task of replacing dwindling numbers of fish stocks.” That quote was from a 1977 report to a Federal Provincial committee on Fishways and stream crossings.
Recent Work Washington 9700 culverts surveyed by 2003 56 % failure rate 7600 miles of isolated or reduce capacity habitat BC MoE Projected focused on high fish values and structures built since 1995. Similar high failure rate. 2000 and 2001 projects by DFO and MoE identified issues with pre-code structures Need has been recognized to priorize and fix fish passage issues. FREP Question: Are forest road stream crossings or other forestry practices maintaining connectivity of fish habitats?
Planning Select watershed(s) using “Fish Value” and 1:50,000 Wshd Atlas Polygons Step 1 “Fish Value” is a provincial strategic tool used to rank watersheds Selection process can be at any level i.e. provincial, regional, district etc.
Watershed Groups: Prince George Forest District T&E MOE Region Forest District Lake Value Salmon Escapement Watershed Code Species Richness SH value Fish Value
Watershed Groups: Prince George Forest District Carp McGregor T&E MOE Region Forest District Lake Value Salmon Escapement Watershed Code Species Richness SH value Fish Value
Planning Overlay known fish presence with specific road networks Step 2 • GIS exercise • Obtain maps of road network • Concentrate on intersection of “known” fish streams and road network ALTERNATE: Random Road Segments tied to Water Quality Assessment
Four Ways to Evaluate Culverts for Fish Passage • Experiments/surveys observing actual fish passage success • Velocity measurements • Hydraulic analysis • Measurement of surrogates indicative of hydraulic conditions
Key advantages: Surrogate measures can be done with people with little training Surrogate protocols can cover more culverts in same amount of time boosting sample size Information can be used in hydraulic analysis if right measures taken The Overview and Detailed protocols used are surrogate methods
Overview Protocol: Used for quick survey of fish passage based on surrogates. Detailed Protocol: Detailed monitoring protocol based on fish passage guidelines like velocity tied back to surrogate measurements. Gives information to evaluate correction alternatives as well as information to determine why a structure has failed. Effectiveness of design, installation. Protocols used
Measurements in and around outlet *Measures should take 5-10 minutes
#14. Outlet drop - Residual Pool Measurements • Pool must be close enough for jump to culvert outlet (good distance and angle) • Base measurements on residual pool surface Current water surface Residual water surface Length Depth
Approach developed in Pilot can be applied to any scale in Province Systematic approach driven by priority watersheds FREP will adapt a randomized sample design. Adequate expertise exists for overview assessment – anyone should be able to do the overview after reviewing the protocol and some training. Detailed assessment will be done to on a sub-sample of problem structures to help determine exact cause of failure and drive continuous improvement. FREP monitoring will allow us to more accurately reflect the scope of the problem. Determine causal agents and improve practices. Richard Thompson – MoE – Richard.Thompson@gov.bc.ca Summary – FREP What’s Next.