|Buffalo Pound High Lift Pumping Station|
CLIENT: City of Regina, Saskatchewan
NHC was retained jointly by Associated Engineering Ltd. and the City of Regina to construct and test a 1:5 scale physical hydraulic model of the Buffalo Pound High Lift Pumping Station. The existing pumping station, constructed in 1989, supplies drinking water to the cities of Regina and Moose Jaw. Within the first few years of operation, inspection of the impellers showed that the first stage impellers were severely damaged. There was also substantial damage observed to the second and third stage impellers. The exact cause of the damage was not known.
A site inspection was conducted to inspect the pumps and assess the damage. The physical model was used to assess whether the sump hydraulics was the cause of the problem. The sump was susceptible to the formation of subsurface vortices; however, their impact would have been minor to the first stage impeller and would not have affected the second or third stages. Modifications were developed to eliminate subsurface vortices from entering the pumps. The majority of the damage to the first stage impeller and all damage to the second and third stages were likely caused by recirculation in the pumps and/or electrolysis corrosion.