The city's 10 pools are now open seven days a week from 1 p.m. to 5 p.m., with each site offering different features designed for children of all ages.
The free entry is drawing families looking for affordable ways to spend time outdoors.
"It feels very exciting, that it's almost summer. It feels nice to just cool off," said Xavier Cervantes.
For many parents, the no-cost access makes the pools an easy choice.
"Free pool for the kids, he can come in jump in go for it. Just spend all day, half a day, whatever they want to do," said Jose Cervantes.
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City officials said the reopening followed months of preparation, including extensive maintenance and inspections.
"Going through the pumps, going through the filters, looking at the surfacing and repairs. It really is a long, long process," said Fresno Parks Director Aaron Aguirre.
Each pool is staffed with four to six lifeguards at all times. The lifeguards are certified and trained in first aid and CPR, providing an added layer of safety for swimmers.
In addition to open swim, the city is offering swim lessons for children at all levels beginning June 22. Every child between the ages of 3 and 17 is eligible for one free lesson.
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Swim instructor Cami Edwards said interest in lessons is growing, with younger children getting involved.
"Kids are coming younger and younger. I see as young as six months in," Edwards said, "it teaches water safety skills and reduces the risk of drowning."
For some residents, the pools are more than just a way to beat the heat - they are a longstanding community tradition.
Danny Martinez said he has been visiting Fresno pools for decades and now shares the experience with his family.
"I've been coming here for about 50 years since 1978. It's been a good little pool. It just brings back memories," Martinez said. "It's just something Fresno has that's still good."
Last year, an estimated 23,000 people visited the city's pools, and officials expect a similar turnout this summer as families return to the water.
When asked how often he plans to visit this season, Xavier Cervantes said, "as often as possible."
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