During the spring thaw period, typically early March to mid-May, some City of Ottawa roads cannot withstand heavy vehicle loads. Every year, the City monitors thaw progression by utilizing the forecast temperature data from Environment Canada and Weather Network to calculate the Thaw Index.
When the Thaw Index reaches its threshold value, the load restrictions are imposed. Depending on the progression of the thaw, restrictions can come into effect quickly, sometimes with only a few days notice. The City also conducts deflection testing to monitor pavement strength as the thaw progresses. Once the pavement strength has been restored, the load restrictions are removed.
As of 12:01 a.m., Wednesday, March 13, 2013 commercial vehicles or trailers with a gross vehicle weight in excess of five tonnes or 11,000 lbs. per axle are prohibited on roads where restriction signage is posted, and on all roads identified as restricted on the Truck Route Maps (Urban Truck Routes [PDF – 827 KB] and Rural Truck Routes [PDF – 1.5 MB]). These restrictions also apply to all non-truck routes.
Heavy vehicles that exceed weight limits on restricted load roadways during the spring thaw period will be subject to fines.
Local restrictions will remain in effect on the identified City roads until further notice (typically, mid May). For further information on seasonal load restrictions, please call 3-1-1.