As the Peel Region continues to expand, managing stormwater runoff has become a central focus of urban planning and environmental stewardship. Traditonal “gray” infrastructure—pipes and concrete basins—is increasingly being supplemented or replaced by Low-Impact Development (LID) strategies. Among these, the infiltration trench is one of the most effective tools for restoring natural hydrological cycles in built-up environments. These subsurface systems are engineered to capture and temporarily store runoff, allowing it to infiltrate slowly into the native soil rather than overwhelming municipal sewer systems.
The design of an effective infiltration trench starts with a thorough analysis of the local soil’s hydraulic conductivity. In Mississauaga and Brampton, the prevalence of clay-dominated soils requires specific design modifications to ensure the trench does not become an “underground pond.” We often specify a greater depth of clear stone to provide additional storage volume or incorporate a subsurface overflow pipe that connects to the secondary drainage system. The aggregate itself is typically 50mm clean crushed stone, providing an ample void ratio (usually around 40 percent) for water storage. This clear stone must be wrapped in a non-woven geotextile fabric to prevent the migration of fines from the surrounding soil into the trench, which would otherwise lead to premature clogging and failure.
Pre-treatment is a mandatory component of our infiltration trench designs in the GTA. To protect the longevity of the system, stormwater must be filtered for sediment and debris before entering the stone gallery. This is often achieved through the use of a grassed swale or a proprietary sediment-intercepting manhole at the inlet. By removing total suspended solids (TSS) at the surface, we significantly reduce the maintenance requirements and ensure that the infiltration rates remain constant over the system’s lifespan. In Peel Region, where winter salt application is heavy, these pre-treatment zones also play a role in buffering the chemistry of the runoff before it enters the groundwater table.
The benefits of infiltration trenches extend beyond simple volume control. They provide essential water quality treatment through the natural filtration and biological processes that occur as water moves through the stone and into the underlying soil. This is particularly important for GTA projects located near sensitive watersheds like the Credit River. Furthermore, by recharging the local aquifer, infiltration trenches help maintain base flows in urban streams and mitigate the “heat island” effect by supporting healthier vegetation in the immediate vicinity. These environmental gains are often rewarded through municipal stormwater credits and easier permit approvals from conservation authorities like the TRCA or CVC.
At Aden Earthworks, we specialize in the precision installation of LID infrastructure that meets the rigorous standards of the Peel Region’s engineering departments. Our team understands that the long-term success of an infiltration trench depends on careful site selection, high-quality material sourcing, and non-compacting excavation techniques. By integrating these LID systems into commercial and residential landscapes, we help create resilient urban environments that can withstand the increasingly volatile weather patterns of Southern Ontario while maintaining the aesthetic integrity of the property.
