A Welcome Urban Oasis : Pasadena: The Rose Bowl pools draw quite a mix--from two boys who hike an hour to get there to a 77-year-old who swam before she could walk.

East side, west side, all around the town, the swim-suited set splashes away the summer hours to the shouts of “Stop running!” and “No diving!” While the Board of Supervisors ponders closing 24 of Los Angeles County’s 55 pools as a cost-cutting step, in the city pools of Pasadena and Culver City, the water remains relatively calm in the storm. Here, two View staff writers report on a day at the cement shores. . . .

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In Spanish, arroyo seco means dry river bed, but you don’t have to translate for David and Michael Leiva. The brothers have been hiking in and out of the Arroyo Seco every day of every summer for the past three years to swim in the cool turquoise waters of the Rose Bowl pools.

From their home in northwest Pasadena, the boys’ round trip takes almost an hour on foot.

“That’s if we don’t stop to play too much--and if we’re by ourselves,” says David, 14, whose trip this day was slowed by his nephew, Joseph Nunez.

As the boys arrive at the pool with their $3 in nickels, dimes and quarters, David points to Joseph and quietly says to the teen-ager at the admissions desk: “He’s only 8. Can he come in? Please?”

The rules say children 8 and younger cannot swim without an adult. But the adults in the Leiva family are busy at their jobs on this day--and every day, according to David, who says he and his eight brothers and sisters “pretty much” take care of themselves.

Yes, Joseph can come in, says the teen at the desk.

The Leiva children, who are of Mexican descent, are in the minority here. But they are here.

When the $6.5-million Rose Bowl Aquatics Center opened in 1990, its stated purpose was “to provide programs for the entire community, with an emphasis on minority and disadvantaged youths.”

That was a far cry from the philosophy that opened the first pool on this site in 1914, according to Aquatics Center literature. Known as the Brookside Plunge, that pool--also a municipal facility--permitted minorities to swim only on Wednesdays--the day the pool water was changed. (Black women were banned completely.) White women and girls were allowed access once a week.

The Leiva boys don’t know about that. They do know that swimming here is “what we like best about having summer,” says Michael, 12.

And if they didn’t come here? David smiles. “Well, I guess we’d get all dried up. Just like the arroyo .”

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Lynn Pierson of South Pasadena could swim before she could walk. So she is not surprised to find herself still swimming at 77.

“I simply cannot seem to stay out of the water,” she says. “My best stroke is on my back--not so hard on the sinuses, you know. And then I swim--oh my, I really don’t count how many laps I swim--40, I guess.”

Winter or summer, sunshine or rain, she slides into the water every Monday, Wednesday and Friday morning at 9 sharp. In the next lane, husband Darrell, 68, is churning the water with his powerful crawl. Darrell, who credits swimming with stabilizing early symptoms of Parkinson’s disease, brings a white kitchen timer to clock their workout: 60 minutes exactly.

Then on to the gym.

“The important thing,” says Lynn, “is to keep going . . . .”

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“No diving, no diving!” shouts the lifeguard.

“No dive-ing?” repeats the little boy in the baggy blue swim trunks.

“Right, no diving. You can’t jump like this with your hands out in front of you. OK? It’s too shallow and you’ll break your wrists.”

The boy, about 4, holds up his wrists and smiles. He climbs out of the baby pool and dives back in.

Rose Bowl lifeguard Vikki Barrett, 22, shakes her head. According to the mothers who watch her watch their children, she has the patience of Job.

Now, Barrett, hands on her hips, says to the boy, “You jumped head first with your hands out in front of you like this. Remember we talked about that? You must not do this. There’s not enough water here. You will break your wrists. You’ll break your head. NO MORE DIVING. OK?”

The boy--who is part of a day-care group--stands up in the pool, puts his hands on his hips and mimics, “No more diving. No, no, no.”

Ten minutes later, the boy is running across the slippery pool deck. Lifeguard Brian Roth, 18, uses his megaphone to shout down from his chair: “No running. No running!” he warns the boy.

The boy stops and looks up at Roth: “Hey, no diving, no diving.”

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Charles Hildebrand, 11, lives in San Marino, but comes to the Rose Bowl Aquatics Center’s world-famous diving school for lessons three afternoons a week. It is a class for beginners so Charles and the other students were surprised one day last week when their instructor asked which of them would be the first to leap from highest board.

Charles, who everyone in class agreed was the best diver, was appointed to leap from the 10-meter platform. To jump from that height is like jumping off a two-story building.

Charles walks confidently to the carpeted edge of the platform and looks down. Below, his classmates yell, “You can do it! You can do it!”

“I know I can do it,” Charles says, but steps back and folds his fingers behind his head. He takes a deep breath, then another. He walks back to the edge.

He looks at the sky and he looks into the deep blue of the diving well. He glances at his digital watch, he shrugs his shoulders and takes another breath.

“Go for it! Go for it!”

“I’m going. I’m going right now,” says Charles.

“One-two-three- Yeeeeeeoooooooooooow !”

His blond hair stands straight up as he falls through the air and lands feet first, like a soldier at attention.

When he surfaces a few seconds later, Charles isn’t talking, just smiling.

“This,” he announces later to his shaken mother, “is a day I will never forget.”