Handling Urban Stormwater

Handling Urban Stormwater

5200mm Span Box Culvert

Anne Street South at Tiffin Street in Barrie is a commercial area with high traffic volume. The area is part of the Hotchkiss Creek Watershed, a relatively small watershed which is approximately 90% urbanized. Of particular concern in the area, is having sufficient hydraulic capacity to handle stormwater and prevent flooding to commercial buildings on Tiffin and Anne Streets.

The Anne Street crossing was previously a series of inline culverts, comprised of a 2.2m diameter CSP culvert, a 1.8m by 1.5m concrete box culvert and a 4.42m by 2.79m CSPA culvert. The CSP culvert had deteriorated significantly. The City of Barrie wanted a quick, but long lasting solution.

Instead of twinning two standard-sized small box culverts, our engineers were able to design one large box culvert to address the required hydraulic capacity and convey the 1:100 year peak flow. The culverts were designed for a live load (CL-625-ONT truck load) and the dead load of 3.0m earth cover. Using one large box culvert, provides greater assurance that the installed hydraulic capacity will match the designed hydraulic capacity. With twin culverts there is increased chance for debris to accumulate, decreasing the flow through the culverts. Accumulated debris can also cause ice damming in the winter.

DECAST manufactured 18 culvert sections, 5200mm x 2750mm. Each section was 1600mm long with a 350mm wall thickness. We provided a layout drawing to the contractor specifying direction of installation, inlet invert and outlet invert. The installation time was reduced significantly, because 18 large culvert sections were installed instead of 36 small culvert sections.