Metro Vancouver has a vision to build a sustainable, livable region. Its Solid Waste and Resource Management Plan aims to minimize waste generation, maximize reuse, recycling and recovery material, recover energy from the waste stream and only then dispose of remaining waste in landfill. Targets suggest reducing the quantity of waste generated per capita to 90% or less of the 2010 volumes and increasing the amount recycled by 80% - all by 2020.
Metro Vancouver is responsible for managing solid waste generated in the Lower Mainland of British Columbia. The rapidly growing region is home to almost 2.5 million people in 21 municipalities, one treaty First Nation and one electoral area.
Publicly owned transfer stations are an integral part of Metro Vancouver's waste management system. The existing Coquitlam Transfer Station services over 200,000 customers every year. The lease of the existing facility expires in 2020 which led Metro Vancouver to weigh options for a newly upgraded transfer station facility. They selected the old Coquitlam Landfill, adjacent to a golf course (which is also constructed on the landfill) and Highway 1.
In 2017, Morrison Hershfield was awarded the design of the new solid waste transfer station for Metro Vancouver in partnership with HDR Corporation and Thurber Engineering. The 120,000 SF facility will receive 600 tonnes of solid waste per day and will feature separate drop off areas for paid and free recycling. Distinct entrances are planned for residential self-haul customers and commercial/municipal packer trucks.
Technical challenges + Teamwork = Innovative Solution
Once complete, the new facility will reside on top of the old Coquitlam Landfill. The facility design considered some unique aspects of constructing on top of an old landfill. These aspects not usually considered in industrial facilities include the mitigation of methane gas, differential settlement due to municipal waste compression, vermin control, cut/fill balance of grading. Also, are there ways to minimize construction costs with the use of residual wastes from other parts of Metro Vancouver’s Solid and Liquid waste operations. Some of the unique challenges, opportunities and solutions are summarized below:
- Landfill gas hazards - specification of an active gas management system, utility “boots” for slab penetrations and a liquid membrane beneath the building slab to manage landfill gas.
- Differential settlement from waste decomposition - a raft foundation, moment and braced frame, and flexible utility connections for the transfer station building.
- Landfill closure requirements – provision for a variety of cover system concepts to suit different areas of the site and stormwater diversion.
- Pest management - specification of building and landscaping design elements to discourage pests from nesting on site.
- Establishing growth in landscaped areas - provisions for the use of wastewater biosolids based growing medium for vegetated areas to reuse Metro Vancouver residuals and lower construction costs.
- Achieving site design grades - use of Metro Vancouver waste-to-energy facility bottom ash and fly ash as site fill to limit the cost of imported fill.
While this project has involved numerous technical challenges, the biggest challenge has been to address the need to deliver a complex project design within a very short time. With little to no flexibility for schedule delay, the team worked diligently with project stakeholders to unearth potential issues at project startup. Each issue was prioritized, with solutions developed to ensure the project schedule is met.
The detailed design is now complete and Stuart Olson has been selected to construct the facility scheduled for completion in late 2020.
On to the Next Challenge
The performance of the Coquitlam Transfer Station design team has moved us closer to our strategic goal of being one of the top solid waste consulting service providers in Canada. The success of this project led Metro Vancouver to entrust our team with the design of another major solid waste infrastructure project, the Surrey Residential waste drop-off facility.
For more information please contact Todd Baker at email@example.com