Abstract: A double suction, single stage volute pump. The pump includes a single piece pump casing (18) which is provided with a single volute defining portion, the portion having a pair of generally circular shroud receiving openings (88, 90). In addition, the pump casing has exterior sidewalls (78, 80) which are disposed on opposite sides of the volute defining portion, each of the sidewalls being provided with an opening (88, 90) in the volute defining portion. A rotary impeller assembly, which includes an impeller (20) and an impeller shaft (22) can be installed into the pump casing from either one side or the other, the impeller assembly passing through a housing receiving opening and a shroud receiving opening until the impeller is properly located within the volute. The pump further includes a pair of impeller shrouds (24, 24) which are secured to opposite sides of the volute defining portion (86), the impeller shrouds covering at least a portion of the shroud receiving openings.