Addressing a Critical Issue for Fish Migration
Across Oregon, thousands of culverts block fish migration, creating significant obstacles for species like salmon, trout, and Pacific lamprey. Many of these outdated culverts create high water velocities, shallow depths, and steep drop-offs, making it nearly impossible for fish to move upstream to their spawning habitats.
Oregon has made great strides in fish passage restoration, but one of the biggest challenges remains: cost. Replacing a culvert with a bridge or an open-bottom structure often costs millions of dollars, making it financially impossible to restore all blocked waterways.
As a fisheries biologist with over 30 years of experience, I have seen firsthand how cost-effective solutions can make an immediate impact. This is why I am submitting comments to the Oregon Department of Fish and Wildlife (ODFW) Fish Passage Task Force, advocating for the implementation of Flexi Baffles—a proven, affordable alternative for fish passage restoration.
What Are Flexi Baffles?
Flexi Baffles are an innovative solution designed to improve fish passage through culverts by reducing water velocity and increasing depth. Unlike traditional rigid baffles (which are often clogged with debris), Flexi Baffles bend under high flow conditions, allowing debris to pass while maintaining a series of pools and steps that help fish migrate upstream.
✅ Reduces water velocity for easier fish passage
✅ Increases water depth in culverts
✅ Does not clog with debris like solid baffles
✅ Low-cost alternative to culvert replacement
✅ Can be installed quickly with minimal maintenance
Successful Implementations of Flexi Baffles
Flexi Baffles have been successfully installed in multiple locations across North America, New Zealand, and Europe, improving fish passage for a variety of species.
Schoenbar Creek, Ketchikan, Alaska
- A 475-foot culvert was resurfaced with concrete and retrofitted with 81 Flexi Baffles, restoring fish passage.
- Material cost: $35,000—a fraction of full replacement costs.
Bon Accord Creek, Surrey, BC
- A 500-foot-long concrete channel, previously impassable for 70 years, was restored using 60 Flexi Baffles, reopening 2.5 km of upstream habitat.
- Material cost: $18,700, installed in just four days.
Reservoir Creek, Nelson, New Zealand
- A 136-meter culvert was retrofitted with Flexi Baffles, allowing inanga and redfin bully to pass upstream for the first time.
Comparing Costs: Flexi Baffles vs. Culvert Replacement
One of the biggest barriers to fish passage restoration is the high cost of culvert replacement. A typical culvert replacement project can cost anywhere from $1 million to $20 million, depending on location, permitting, and infrastructure needs.
Real-World Cost Comparisons:
| Project | Culvert Replacement Cost | Flexi Baffle Retrofit Cost |
|---|---|---|
| Harris Creek, WA | $5,319,000 | $8,900 + one-day labor |
| Watercress Creek, WA | $1,878,000 | $4,700 + two-day labor |
💰 In both cases, Flexi Baffles saved over 99% of the cost compared to full culvert replacement!
Why Oregon Needs to Act Now
According to the National Aquatic Barrier Inventory, there are over 775,000 road-related aquatic barriers in the Pacific Northwest, with tens of thousands of culverts restricting fish migration in Oregon alone.
Yet, fewer than 0.5% of these barriers have been removed or mitigated due to funding limitations and infrastructure constraints.
We need cost-effective, practical solutions that can be deployed quickly. Flexi Baffles provide exactly that.
My Recommendations to the ODFW Fish Passage Task Force
I am urging the ODFW Fish Passage Task Force to:
1️⃣ Pilot Flexi Baffle installations in high-priority culverts across Oregon.
2️⃣ Incorporate Flexi Baffles into Oregon’s fish passage guidelines as a cost-effective alternative to full culvert replacement.
3️⃣ Work with municipalities and transportation agencies to integrate low-cost fish passage retrofits into infrastructure planning.
By taking proactive steps now, we can restore critical fish migration pathways, support Oregon’s salmon and lamprey recovery efforts, and make fiscally responsible investments in our aquatic ecosystems.
Join the Conversation!
I invite fellow biologists, conservationists, policymakers, and anyone passionate about fish passage solutions to join this discussion. Let’s work together to implement cost-effective strategies that truly make a difference.
👉 Have experience with fish passage restoration? Leave a comment below!
👉 Interested in learning more about Flexi Baffles? Let’s connect!
#FishPassage #SustainableConservation #FlexiBaffle #ODFW #CulvertRetrofit #SalmonRecovery #AquaticOrganismPassage
