Sidewalks can be so much more than just a surface to drag our tired feet along as we trudge through city life. A new pilot project in Toronto is proving that sidewalks can be a tool in improving the environment around us, even sustaining life.

In 2020, a single block of sidewalk along the south side of Lake Shore Boulevard East was quietly transformed into a system that filters stormwater runoff through the soil, sustaining an adjacent plant bed.

It's an innovative system being tested as part of the Lake Shore Boulevard East Sidewalk Pilot Project; the results to shape the future design of the arterial and provide insight that could be used citywide under the new Green Street Standards program.

The strip of sidewalk at 12 Bonnycastle Street, located just east of Sherbourne Common, turns heavily-polluted city stormwater and melting snow runoff into clean water for adjacent plants, filtering out road salt and other pollutants.

The stretch of sidewalk along Lake Shore Boulevard East at Bonnycastle Street.

This doesn't just sustain the adjacent plants, but also promises to improve overall water quality if widely implemented. Stormwater washing over hard surfaces like asphalt and concrete can easily overwhelm storm drains, carrying pollutants into waterways and Lake Ontario.

Replacing impermeable sidewalks with porous surfaces minimizes the potential for flooding, but what happens to the water once it seeps through the cracks in the sidewalk?

Below the porous pavers, stormwater storage collects water while another pipe drains excess water off-site to prevent plants from drowning during heavy rainfall.

The passive irrigation system distributes water via a pipe to the planting area, while stored water is used to keep plants hydrated during drier times.

The plants themselves are salt- and shade-tolerant, chosen specifically to withstand the harsh urban conditions of Lake Shore East. In addition to greening the bleak concrete and asphalt-lined stretch, the plants double as a separation feature, adding more distance between pedestrians and the thoroughfare's fast-moving traffic.

And the city isn't just playing a game of set it and forget it here, as the pilot project is being monitored to evaluate how these upgraded sidewalks improve stormwater management and street plantings, and how much extra maintenance they require compared with standard sidewalks.

If the pilot project performs, the full Lake Shore Boulevard East Public Realm Plan could get similar water-filtering, plant-quenching sidewalks, with possible further implementation through Toronto’s Green Streets projects.