The centre's other facilities, including the learner pool, gym and squash courts, will re-open as planned on Saturday 1 May.
Urgent work has started today to repair a leak that was discovered when the main pool was refilled in preparation for the centre re-opening.
When the pool was refilled it was noticed that it was using excessive levels of water. Investigation works using cameras were carried out and a leak to the water supply line at the shallow end of the pool was discovered.
Excavation works and major repairs to the pipework have begun today to avoid further water loss and damage to the infrastructure of the pool.
When these works are completed the pool will then be topped up and brought up to temperature ready for re-opening.
The new date for the pool opening will be announced as soon as possible and the leisure centre will be contacting anyone affected by the delay.
"We have carried out a significant amount of work at the leisure centre over the last 12 months to get it ready for re-opening including extensive roof repairs and internal heating works," said Cllr Mike Solomon, North Somerset Council's executive member for neighbourhoods and community services.
"This latest situation is extremely frustrating but was something which could not have been predicted and only came to light when the pool was refilled. However, carrying out these emergency works, along with the work that has already been done, will provide a better facility for the users.
"The repairs to the pipework will provide improved water quality to the swimming pool."