Groundwater Resources Pembina Area, Alberta

Nearly 60 per cent of the water utilized for secondary recovery operations in the Pembina oil field is obtained from the Paskapoo formation. The present annual withdrawal from this formation is about 600000000 gallons per year. The apparent transmissibility of the Paskapoo formation is variable; however, in only a few isolated areas are well yields less than 5 gallons per minute. At the present rate of withdrawal it is estimated that the piezometric surface of the Paskapoo formation will be lowered less than 24 feet over the entire area. In a few parts of the area the local overdraft will be considerably greater. Observation wells completed in the Paskapoo formation indicate that to date there has been no significant decline in the piezometric surface. The decline observed in a few very shallow observation wells is ascribed to changes in surface drainage rather than to withdrawal of water for pressure maintenance. It is considered that the present rate of withdrawal, continued for the anticipated life of 40 years for the oil field, will not significantly decrease the amount of water available for agricultural development.