Winter Performance of Inter-Locking Pavers—Stormwater Quantity and Quality

Abstract: This study examined the effectiveness of open-joint inter-locking pavers in a permeable pavement in cold (winter) conditions. A field-scale inter-locking paver cell (UNI Eco-Optiloc^®) was built to evaluate the hydraulic performance and water quality improvements experienced during freeze-thaw and frozen conditions in Calgary, Alberta, Canada. Hydraulic performance was assessed using stormwater runoff reduction (peaks and volumes) and surface infiltration capacity. Water quality performance for removal of total suspended solids (TSS), total nitrogen (TN), total phosphorous (TP) and three heavy metals: copper, lead and zinc, was assessed. Results from the study demonstrated that the inter-locking pavers were effective in attenuating stormwater runoff peak volumes. The surface infiltration capacity decreased significantly due to the deposition of sanding and de-icing materials on the pavement surface during winter operation. Infiltrated stormwater was stored and treated within the pavement structure, which showed removal rates of 91% for TSS, 78% for TP, 6% for TN, 68% for zinc, 69% for copper and 55% for lead.