V ancouver’s experience shows that the path to climate resilience With mounting regulatory pressures and rising community expectations, Vancouver’s engineers faced a familiar dilemma when assessing the city’s century-old sewer and stormwater systems: dig up streets to install larger pipes or try something different. Rather than relying solely on traditional upgrades, the city explored a complementary approach — one that could deliver resilience while unlocking a wide range of co-benefits. The solution did not emerge from a single capital project or regulatory mandate. Instead, it flowed from Vancouver’s Rain City Strategy,¹ which reframed asset management to fully integrate green infrastructure. By applying disciplined, lifecycle-based management principles to green infrastructure, defined as tree trenches, wetlands, bioswales and permeable pavement, the city has achieved measurable gains. A problem every city faces Vancouver’s challenge mirrors municipalities is more than new, greener infrastructure: it’s about changing how cities plan, govern and integrate what they already have. everywhere.² Storms are becoming more frequent and intense, while urban growth replaces natural ground with hard surfaces that pool, rather than absorb, rainfall. The traditional response of upgrading pipes and treatment plants, referred to as grey infrastructure, is expensive and disruptive. These projects can cost millions of dollars and affect communities for months at a time. Vancouver began asking a different question: how could green infrastructure work alongside existing systems to extend their lifespan and deliver benefits that pipes alone cannot?
From roads to rainways This approach was put to the test on a deteriorating local roadway that experienced persistent flooding. Working closely with residents, the city developed the St George Rainway, a blocks-long blue-green system designed to manage stormwater more naturally.³ A rainway is a park- like network of green rainwater infrastructure features, such as rain gardens that use plants, trees and soil to manage the rainfall. These living systems work with pipes, streets and other parts of the built environment to capture and clean rainwater before returning it to the ecosystem. Culverts, stepping-stones and boardwalks allow residents to move through the space, integrating everyday use with effective water management. A new shared asset management strategy Cities have experimented with rain gardens and bioswales for years. What sets Vancouver apart is the systematic, programmatic way these living systems are managed as municipal assets. The core challenge is governance, not technology. Traditional asset management models assume single ownership: one department is responsible for one type of infrastructure. Green infrastructure breaks that mould. A single bioswale, for example, may involve the water utility for drainage performance, transportation for street integration and parks for vegetation maintenance.
Nexus Magazine | GHD | 17
Made with FlippingBook - professional solution for displaying marketing and sales documents online