The Tinwald Community Pool is now closed from Monday to Friday but will be open at the weekends from noon to 7pm.
The change in hours is due to the recent drop in patronage on the weekdays and a shortage of lifeguards needed to monitor Ashburton's other swimming complex as well as the Tinwald Community Pool - at the same time.
"It's not what we want to do, but it is something we need to address because we just don't have enough lifeguards at the moment to cover two pools operating seven-days a week," says Sports Facility Manager Steve Prescott.
Council is currently recruiting for more lifeguards and is encouraging interested candidates to put forward their applications.
"You don't need to have had lifeguard experience to apply however you will need to be prepared to do lifeguard training, be able to swim 200 metres in under six minutes and must hold, or be willing to gain, a First Aid Certificate," says Mr Prescott.