A common mistake we see from contractors working in Drummondville is assuming that a slope that looks stable after a dry week will hold up during spring thaw or after a heavy rainfall event. The region's glacial till and clay layers behave very differently once pore pressures rise, and we have been called to several sites where a cut slope failed overnight because nobody checked the factor of safety under saturated conditions. That is why we always recommend a proper slope stability analysis before any excavation deeper than 1.5 meters, especially when the site borders the Saint-François River floodplain. By combining field data from a density cone sand replacement test with laboratory shear strength parameters, we can model realistic failure surfaces and give you numbers you can trust.
A slope that survives a dry week can fail overnight during spring thaw when pore pressures rise in Drummondville's silty clay.