A swimming pool which a council said was not "financially viable" could close.
Campaigners said Aquasplash in Minehead, Somerset was closed temporarily last November after the pool developed a leak.
Repairs were estimated to cost up to £15,000. West Somerset Council is due to vote on whether to repair it at a meeting on Wednesday.
It is also believed Tesco wants to use the site to expand its nearby store.
Campaigner Elkie Winzer said the nearest alternative pool was an hour's drive from the town in Taunton.
"I have two sons aged three and five and they have had their swimming lessons cancelled.
"We live near a river and the sea and like many other parents we are concerned about our children falling in and drowning."
A Tesco spokeswoman said: "We are interested in hearing the outcome of tonight's meeting and, as always, are looking at ways of improving our stores.
"But we would like to speak to people in the town and the local council to see how we can go forward."
West Somerset Council said it recognised and acknowledged the local community's desire to keep Minehead's Aquasplash leisure facility open.
A spokesman said: "After much work and research, it has been acknowledged by both parties that all available options would leave the council, any potential partner and the taxpayer at high financial risk.
"The costs of upkeep on the ageing facility, which is currently closed due to leakage from the pool, will also inevitably increase with time.
He said a report would recommending permanent closure would be presented to the meeting.
Earlier this year plans to close a pool in Burnham-on-Sea were delayed following a 6,642-name petition and protests by swimmers.