Brandon Manitoba sits on a thick sequence of glacial till and lacustrine clay deposited during the last ice age. The local water table fluctuates between 2.5 and 4.5 meters depending on season and proximity to the Assiniboine River. These conditions make the SPT (Standard Penetration Test) an essential tool for foundation design. The test records blow counts per 300 mm of penetration, giving engineers a direct measure of relative density and consistency. For projects near the river valley, where sand lenses interbed with stiff clay, a single borehole may show N-values jumping from 8 to 35 within two meters. That variability is exactly why a properly executed SPT matters here.
A single SPT borehole in Brandon's glacial till can reveal N-values ranging from 8 to 35 within two meters, directly affecting foundation cost and safety.