Summit Earthworks Inc. was selected by the District of North Vancouver to complete the removal of an existing 1500mm Stave Wood Culvert and install 18 lineal meters of 4.20m wide x 1.8m High Concrete Box Culvert. Additional tasks included Channel Restoration & Bank Protection on Carnation Street in North Vancouver.
The project site is situated within Seymour Heights, Blueridge Creek starts north of Berkley Avenue and flows south. The creek was challenging to follow through the neighbourhoods of Blueridge and Seymore Heights. Most of it has been culverted through much of the residential area, which was primarily established in the 60’s.
Summit removed the original 1500mm wood stave culvert and concrete headwalls, which were determined to be undersized for a 200-year stormwater event. During the removal, Summit’s project manager noted that some previous maintenance efforts had been performed on the old wooden stave culvert in the past as the inside was retrofitted with reinforced bolted steel collars. The old culvert’s removal was completed during the approved fish window and required a full road closure and traffic and pedestrian management strategy. A bypass was implemented to allow the creek to flow during a rain event within the construction period. The existing sanitary and storm mains required a full disconnection, bypass and reconnection daily. The water main remained functional throughout and was supported by a lift system during excavation. The new culvert was a precast 4.25m x 1.8m precast concrete box culvert from Langley Concrete and cast in place inlet and outlet concrete headwalls. Due to the high velocity of water flows within Blueridge creek, the engineer had specified that rip rap within the box culvert was set within 28 MPA concrete, this work was completed by hand due to the space constraints within the culver. Locally sourced rip rap was used to rebuild 8 meters of creek bed downstream and 6 meters of disturbed creek bed upstream of the project site. All disturbed areas received new topsoil and were replanted with locally sourced native riparian species.
The general scope outline and project activities include:
- Tree Falling, Chipping and disposal by pre-approved District of North Vancouver arborist.
- Removal and disposal of old concrete headwalls and 1500mm wood stave culvert.
- Re & Re of existing utilities.
- Installation of precast concrete box culvert 4.25 meters wide x 1.8 meter high.
Creek Bank & Channel Restoration 1:1 H:V Slope
- 75 Lin.m. – 4.25m x 1.25m Concrete Box Culvert.
- Cast in Place Concrete – Inlet Debris Barrier, Culvert Outlet Head Wall, Culvert Inlet Head Wall.
- 30 m3 – Concrete Rock Bedding within Culvert.
- 300 Tons – 50 – 150mm Coho Gravel.
- 600 m3 – Native Backfill.
- 350 m2 – Nilex SC150BN ECB.
- 200 Tons – 450-650mm Rip Rap.
- 100 Tons – 150-300mm Rip Rap.
- 75 Tons – 300mm Rip Rap Set in Concrete within Culvert.
- 250 Tons – 300-500mm Washed Round Boulders.
- 150 Tons – 200-300mm Washed Round Boulders.
- 48 Pcs – 500mm Washed Round Boulders.
- 1400 Tons – 75mm Minus Crushed Granular Subbase.
- 1000 Tons – 19mm Minus Crushed Granular Base.
- 45 Tons – Machine Laid Warm Mix Asphalt.
- 12 Lin.m. – Galvanized Steel Pipe Handrail.
- 10 Lin.m. – Type 1 Cedar Fence.
- 35 Lin.m. – Type 2 Cedar Fence.
- 75 Lin.m. – Type 3 Cedar Fence.
- 90 m2 – 150mm Thick Topsoil.
- 250 m2 – 450mm Thick Topsoil.
- Riparian Planting Pockets.
- 90 m2 – Hydraulic Seeding.
- 11 Lin.m. – 300mm SDR 35 PVC Storm Sewer.
- 11 Lin.m. – 375mm SDR 35 PVC Storm Sewer.
- 4 Lin.m. – 200mm SDR 28 PVC Catch Basin Leads.
- 2 – 900mm Catch Basins.