Parents are outraged a Wollongong swim school, which has been open for more than 45 years, will be forced to close after the council received a complaint about parking outside the complex.
Generations of Wollongong residents have learnt to swim at the Smith Street pool, located within a group of residential units.
The pool has never held a development application - a detail the council has been happy to overlook for the past five years while it has conducted inspections and water quality checks for a fee.
But a single complaint from a neighbouring resident about parking in the street has prompted the council to swing into action, and Sharon Crisafi, who took over the business 25 years ago, has announced the pool will close on June 28.
"Since receiving the [council's] letter I have had several meetings with the council planner and a private planner," Ms Crisafi said.
"They informed me that I would not get council approval as the area is zoned R1 and the running of a swim school in this zoning is prohibited.
"This has been an extremely stressful time for my family and I ... and has been compounded by the extra stress of having my husband recently diagnosed with a rare small bowel cancer."
Ms Crisafi said she had looked into moving the swim school to a warehouse pool, however, strict council laws meant it wouldn't be economically viable.
"As I believe I have covered all areas to try and remedy the situation, without success, I have no choice but to close," she said.
The decision has left the parents of up to 60 children who use the school wondering what to do next.
Mother-of-three Alita Ashcroft said she valued the school for its flexibility with teaching.
"She takes on two of my children at the one time so I don't have to be here for a good hour-and-a-half," she said.
"It's extremely convenient but she also gets results.
"They're comfortable in the water and can now save themselves which is my main priority - we live on the water, we live on the beach."
Parent Daniel King said Ms Crisafi's methods were good because parents weren't required to get in the water with their children while they were swimming.
"I'm going to have to travel further ... and it's probably going to be more expensive as well," he said.
However, a council spokesman said Ms Crisafi still had the opportunity to "explore the possibility of lodging a development application seeking to authorise the swim school, subject to compliance with council's statutory documents".
"The council is working with the school and to this end has provided additional time for the school to lodge their application," he said.
"A search of council's records indicate that approval has not been obtained for the swim school. It is incumbent on businesses to ensure they have the correct approvals."