AquaZone's two swimming pools will be closed for seven weeks for a $1 million upgrade.
The pools will be drained and closed to allow the installation of new air handling and water treatment systems at the aquatic and fitness centre.
Work will start on the $985,000 upgrade from July 1 and is expected to finish in August.
Warrnambool City Council said while works are underway, the 25-metre, program and leisure pools will be off limits to the public.
Chief Executive Officer Peter Schneider said the upgrades would result in a better indoor pool environment and a safer water treatment operation.
"We know that AquaZone is a valued community asset used by large numbers of people and it's important that we invest in the centre to ensure it meets the community's expectations," Mr Schneider said.
"Moving from a gas to a liquid chlorine system is safer for patrons and also staff operating the system."
AquaZone manager Ray Smith said all of the other services at the centre, including the gymnasium, crèche and group fitness classes would operate as normal.
"All our prepaid memberships and swim school enrolments will be automatically suspended over the period," Mr Smith said.
"Direct debit fees will decrease to reflect the closure.
"Additional time will be added to the end of upfront memberships to offset the time lost.
"The expiry date of all swimming multi passes will also be extended to reflect the time lost during the closure.
"No changes will be made to gold, gym or fitness memberships, however additional dry area fitness programs will be scheduled for the period. Gold, Gym and Fitness members will also have the option to suspend their membership over the period."
The council has advised there is the option to cancel memberships or visit passes.
"I encourage anyone with any queries to consult the customer service staff at AquaZone," Mr Smith said.
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