Project partners met in early November to discuss the work that occurred on the Seymour River Rockslide Mitigation Project to date (in 2016). Presentations were made by the Seymour Salmonid Society and BGC Engineering Inc. (See both presentation below). The Society spoke about the effort being made to conserve fish population while restoring the migration route through the slide area. BGC Engineer, Sam Fougere focused on the technical details of the project work.

All partners are very pleased with the work that has happened thus far but there is still a long road ahead. We will keep you posted as things progress in 2017. 


The amazing engineers we are working with at Northwest Hydrolics Consultants passed on these links.

It gives an idea of the indepth mapping and imagery that is being done on the Seymour River Rockslide Mtigation Project:





As of August 22nd, 2016 work has begun to breakdown the large rocks from the 2014 slide. Crews began work at the toe or downstream portion of the slide. The picture below shows a channel is being re-formed,  previously filled by rock and debris. On the left is the before picture (note the big boulder in the centre), on the right shows after it was broken down, no evidence of the boulder remains.



Without the support of our funding partners this project would not be possible. A huge THANK YOU to:






On December 7, 2014 a catastrophic landslide deposited 50 000 m3 of rock into the lower canyon of the Seymour River. The debris blocked downstream juvenile and upstream adult salmon migration, from and to productive habitat areas. The Seymour Salmonid Society aims to restore fish passage through the slide using non-explosive techniques, a project that will span one to five years. Manual transportation of fish around the slide has been labour-intensive and unsustainable given the number of fish successfully transplanted. In the interim, a floating fence will be installed in the lower river to allow for effective, low-stress capture and transport and potentially provide high-precision stock assessment data. Once fish passage is restored through the blockage, acoustic and radio tagging programs and regular stream surveys will be used to monitor project effectiveness.

The rockslide occurred in the Lower Canyon of the Seymour River in the Lower Seymour Conservation Reserve, North Vancouver, BC at 10U 499819 m E 5465003 m N. Stream flows on the river were first altered on a small-scale in 1927 when the river was originally dammed and on a large-scale in 1961 when the present day Seymour Falls dam was constructed. The rockslide occurred approximately 14 kms downstream of the dam and blocked aquatic access through the slide region. The majority of productive spawning and rearing habitat for salmon lies upstream of the slide, while the downstream region is primarily developed land. The Seymour River is a designated wild coho and winter and summer steelhead stream. Steelhead are currently listed as a conservation concern due to results from a Provincial angling assessment of Seymour River steelhead (1983-present day). If fish passage is not re-established immediately, coho and steelhead will likely be reduced to remnant populations as early as 2019. Pink, chum and Chinook salmon also access their spawning and rearing habitats through the slide area. While some spawning does occur below the slide for these species, their populations could also be significantly reduced within the same time frame.

Many of the plants and animals of the surrounding ecosystem rely on salmon as a food source and supply of marine-drive nutrients. Without the restoration of migrating fish to the affected area, these organisms could be significantly impacted. We strongly believe that the Seymour River qualifies as a stream at risk. It is also important to mention that over 40,000 mof habitat creation projects have been undertaken in the Seymour River watershed upstream of the slide. These off-channel rearing and spawning habitats are currently devoid of fish and will continue to be unless this project can successfully reshape the debris and restore fish migration.

The goal of this project is to restore fish passage through the rock slide, thereby reducing habitat fragmentation and loss and reducing the threat of stream degradation / ecosystem health. The objective of this project is to re-establish fish passage by use of low-explosives, specifically rock drilling and NXburst, allow the broken-down debris to relocated hydrologically by high-water events. This is the safest, most natural and least invasive method for workers, river users, and ecosystem inhabitants. This work will be an iterative process based on safe in-stream work opportunities immediately prior to high-water events. It is estimated that each rock-breaking opportunity will occur over a 4-7 day period, 6-10 times per year until acceptable water flows and fish passage are restored. Weather and water levels permitting, work will begin in late March 2016.

Until passage is restored, a floating fence will be placed closer to the mouth of the river in order to capture fish before they become trapped below the slide. The fence has the potential to provide high-precision stock assessment data which will be used in conjunction with fish monitoring data collected from the slide once work commences.

The physical reshaping of the slide debris will be conducted by Northwest Hydraulic Consultants and BGC Engineering. Work will be overseen by staff from the Seymour Salmonid Society as the primary proponent, Metro Vancouver and Fisheries and Oceans Canada. Other key stakeholders in this project will include the District of North Vancouver, the BC Ministry of Forests, Lands and Natural Resource Operations, Habitat Conservation Trust Foundation, Pacific Salmon Foundation and the Freshwater Fisheries Society of BC, Squamish and Tsleil-Waututh First Nations and community volunteers to assist with monitoring thesis writer service and Kintama Research and InStream Fisheries Research to assist with tagging and monitoring. Roundtable and public information meetings have been and will continue to be held for other community members and river users who are unable to participate as volunteers.

It is important to note that this type of project has not been conducted before in this or nearby regions. Therefore, as pioneers of this endeavour, we have no examples or standards to follow. While the most qualified individuals have been consulted in all matters of mitigation and planning to date, the project will have to be modified as needed.

The ultimate measure of success for this project will be the restoration of water and fish passage at low water levels. Prior to the commencement of the project, radio and acoustic tags were applied to both upstream-migrating adult steelhead and downstream-migrating steelhead smolts. Receivers were placed at either end of the slide debris and mobile trackers have been in place since June of 2015. Movement will continue to be monitored on all receivers in conjunction with visual stream surveys of rearing and spawning habitat. Application of radio tags to semelparous adults will continue as individuals return to the Seymour River. Success will be determined by the percentage of tagged individuals that are able to move past the slide and by the presence of spawning adults visually confirmed above the slide.

CBC Early Edition Interview

Read the article here:

Salmon rescuers to blast rock to help fish spawn in Seymour River


As we approach our first round of rock breaking the District of North Vancouver will be sending out a letter to residents with some details regarding the project and when they can expect work to begin and trails to be temporarily closed.




Subject: Notification for fish habitat restoration – Seymour River

FCBC has accepted your application and forwarded it to Resource Management (RM) for their records.

The tracking number assigned to your application is: 100154951   

Date Received: Jan 21, 2016      

Work Window:  Mar 15, 2016 – Mar 15, 2019


The Society has been writing letters to Ministers at different levels of government requesting funds to help mitigate the rock slide. Below is a response from Federal Minister Hon. Hunter Tootoo. Unfortunately we didn’t  get the response that we had hoped but will continue to pursue different funding avenues to resolve the issue on the Seymour River.

Letter from Federal Minister


JANUARY 19, 2016

The 2016 season is underway! We will continue to use our dedicated broodstock anglers to help bolster our stock on hand and eventually move excess above the slide. Please note that anglers are operating under Federal and Provincial scientific collection permits – there is no public retention of steelhead in the Seymour River.

Depending on river conditions, we may augment these efforts with more tangle-netting sessions. Keep an eye on your email for upcoming volunteer opportunities on the river! If you are not on our email list, you can sign up to receive all volunteer opportunities by email by filling out our volunteer form.

The floating fish fence is set to be installed in the spring of this year. The fence will be operational approximately six months

The proposed floating fence will be similar to the one pictured above

The floating fence will be similar to the one pictured above

of the year until passageway through the slide can be restored. It has the potential to provide us with high-precision stock assessment data for all migratory species in the river which will allow us to manage the Seymour more effectively.

An agreement in principle regarding a permanent mitigation method for the rockslide has been reached by Seymour Round-Table members from six levels of government including Fisheries and Oceans Canada, BC Ministry of Forests, Lands and Natural Resource Operations, Metro Vancouver, District of North Vancouver, Squamish First Nations and Tsleil-Waututh First Nations.

Northwest Hydraulic Consultants and BGC Engineering will re-shape the slide debris with scaling crews, low-velocity explosive rock-breaking and river flows. The method uses non-conventional rock breaking techniques and will require limited heavy equipment. River hydraulics will redistribute 10 000 – 20 000 m3 of material into a gradient that can be utilized by all salmon species. This method would be the safest and least disruptive to the surrounding ecosystem and will likely take between two and five years.

Our vision statement for the Seymour Rockslide Mitigation Project is

“To restore migration conditions for all species in the Seymour River that existed before the 2014 rockslide, in a safe and sustainable manner.”

This project will require a large amount of funding. We have applied to a number of grants to help assist us in this matter. To donate directly to the rockslide mitigation efforts, please click the Fundraise for the Rockslide button on the right-hand side of this page.

Our next step is to host a public forum. Details will be posted here once they have been confirmed.


On December 7, 2014, a rock fall estimated at 50,000 cubic meters, impacted the Seymour River, at a location at the upstream end of the lower canyon. The debris field from this slide raised the water level in the river some 10 meters creating

Photo credit: Simon Ager

Seymour Rockslide – Photo credit: Simon Ager

a blockage to downstream-migrating juveniles and upstream-migrating adult salmon. The upper Seymour River, above the rock fall, contains the large majority of the productive salmon habitat in the watershed, and therefore there are justified concerns about the health of the Seymour River salmon run in coming years, if migration past the rock fall is not restored. In fact, coho and steelhead could be reduced to remnant populations by as early as 2019 if we are unable to mitigate the effects of the slide.

To scientifically confirm whether or not fish are able to pass through the debris, juvenile steelhead were acoustically tagged and adult coho and steelhead were radio tagged. Pacific Salmon Foundation, Fisheries and Oceans Canada, BC Ministry of Forests, Lands and Natural Resource Operations, UBC, Kintama & Freshwater Fisheries Society of BC contributed emergency funding and equipment for the tagging programs. Receivers were placed at both the downstream and upstream end of the slide and mobile trackers were deployed. To date no fish have been detected by fixed or mobile receivers.

Snorkel surveys conducted in July of 2015 confirmed that a number of fish were holding in two pools directly below the slide debris.

Photo Credit Brian Har

PVC Trap – Photo Credit Brian Har

Fisheries and Oceans Canada is working in partnership with the Seymour Salmonid  Society, Metro Vancouver, Squamish Nation, Tsleil Waututh Nation and North Vancouver District, to attempt an emergency rescue effort to capture returning salmon in the lower Seymour  River. Salmon recovered from these efforts will be placed in transport tanks and  transported to the Seymour River Hatchery until target broodstock numbers are achieved. Surplus fish will be released directly into the upper Seymour River, above the slide and below the dam.

Initially, a PVC and net trap was set up in the lower river adjacent to the Squamish Nation Band Office. High-water events due to summer storms thwarted these methods and hoop nets and seine

Photo credit: Brian Har

Hoop Net – Photo credit: Brian Har

nets were quickly put to use. These methods proved highly successful for pinks, but staff was forced to adapt once again for coho and steelhead. Tangle nets and angling is currently being used to capture fish out of the lower river with good success.

All 2015 in-river work is done with hand labour and does not require heavy machinery access this season. Vehicle access in close proximity to the river bank near the capture sites may be necessary, given that all trap materials and captured salmon must be moved by hand from and to transport vehicles. Captured salmon will be moved by field crews to the transport tanks daily depending on capture success in the river trap.

Seymour Salmon Society Fish Rescue - Sombilon Photography-54

Tangle Net – Photo credit: Sombilon Photography for PSF