6. The Guelph Lake reservoir, located in the north of the city, upstream of gauging station, was created in 1974 to help regulate the discharge in the Speed River. That

is, the Guelph Lake dam was intended to increase discharge in the downstream river during low-flow conditions and to reduce the likelihood of flooding during high-flow conditions. Calculate the averages of the annual extreme flows (both minima and maxima) for the pre-dam and post-dam periods. How effective has Guelph Lake been for regulating the annual discharge extremes? (5 marks)