By Amanda Scotese

BASKING IN THE light and humidity of the Bay Area's many public pools is a damn good way to pretend it's actually warm in this cold city. You won't get a sunburn, you won't get sand in your ass, and best of all, swimming gives all the major muscle groups an extremely low-impact workout, so it's a primo way for everybody – including people with special needs – to get their booties moving.

The San Francisco Recreation and Park Department doesn't advertise its nine pools, and therefore they remain an underground secret. Attendance is usually low despite the reasonable $3 admission fee (50¢ for under 17; multiple-use and family passes are also available).

All Rec and Park pools offer lap swims and swimming lessons ($1) for adults and children, and certain pools have an eight-week Summer Learn to Swim course in which children can earn Red Cross certification. Most pools hold water aerobics classes, where participants can burn mucho calories, improve flexibility, and build rock-hard muscles. Thanks to the water's resistance, classes are low impact and lessen the risk of injuring joints, bones, and muscles. Some pools have special classes for seniors, pregnant women, and people with diabetes, asthma, and multiple sclerosis. Several swim instructors and lifeguards report that they have regulars for classes and lap swimming.

Rec and Park's pools, locker rooms, and rest rooms are all quite clean – although, sadly, a few of the pools have fallen into a shabby state, such as Hamilton in the Western Addition. With piles of dead leaves in cracked cement corners and beams marbled with peeling paint and rust, Hamilton appears from the outside to be abandoned, even though a potential well of fitness awaits inside. The department is, however, discussing how to begin a comprehensive pool-maintenance program.

You can check out the aquatic program schedules for each pool on the department's Web site (www.parks.sfgov.org/aquatic/aquatic.htm) or at the pools themselves. The days and hours open vary at all locations.

The park around Garfield Pool may attract some sketchy characters at times, and yet the pool has the second largest attendance of all Park and Rec pools. Like a few other pools, it could be a sunny swimming experience, with its wall of tall windows, but instead yellowed Plexiglas blocks some of the light. Despite its aesthetic downfalls, the Garfield Pool offers a variety of excellent classes, including one for pregnant teenagers. 1271 Treat, S.F. (415) 695-5001.

Hamilton Pool looks like an abandoned building from the outside, but inside tunes like James Brown's "Jungle Boogie" provide a lively beat for wet exercise. The pool holds the standard lessons and lap swims, as well as meetings for the Tsunami Masters Team, a competitive swimming group affiliated with Pacific Masters Swimming and the International Gay and Lesbian Aquatics Organization. The group meets Monday through Thursday and Saturday and welcomes everybody from novices to hardcore swim fanatics. Membership should be arranged beforehand through its Web site at www.sftsunami.org. Geary and Steiner, S.F. (415) 292-2001.

Martin Luther King Pool in Bayview-Hunters Point puts all the other pools to shame. The spacious, sunny facility was completed last year and includes a 75-by-42-foot pool, a separate toddler's wading pool, bleachers, and a community room where people can hold meetings or throw birthday parties. The air temperature is kept at 84 degrees to prevent condensation on the building's steel beams. This steamy temperature means you can fool yourself into believing it's actually a warm summer day as you meditate on the wave reflections shining on the pyramid-shaped ceiling. King Pool offers lessons such as lifeguard training for teens and adults and special water exercise classes catered to people with diabetes, multiple sclerosis, and asthma. Keith and Carroll, S.F. (415) 822-2807.

Renovation of Mission Pool, Rec and Park's only outdoor swimming hole, is expected to be completed soon. Kids love having handstand contests and yelling "Marco Polo" in the pool's large shallow end. Unfortunately, for those not splashing around, the chill-out area is only a narrow strip of cement surrounding the pool. The new entrance will be on 19th Street, rather than the former entrance on Linda, where a giant 1985 mural of break-dancers and rockers with triangular guitars brightens the alleyway. 19th St. at Linda, S.F. (415) 695-5002.

North Beach Pool's temperature of about 83 degrees and its aqua floor make it the Caribbean fantasy of public pools. Most of the San Francisco public pools were built in the 1950s with pretty much the same simple design of a slanted ceiling and a long wall of windows, but North Beach pool's abstract arrangements of white, faceted acoustical tiles give it an accidentally hip style. This pool, along with Mission Pool, gets as shallow as three feet, a depth that allows for preschool classes. The pool's floor has some cracks in it, and the city has drafted a renovation plan for the pool facility that is due to begin January of next year. 651 Lombard, S.F. (415) 274-0200.

A sleek stairway constructed by the Works Progress Administration in the 1930s leads past a canopy of vines and a thickly verdant lawn to Rossi Swimming Pool in the Richmond. In this bucolic setting, the standard 1950s pool facility waits to dampen your sun-starved bum. The friendly staff and regulars who frequent Rossi's lap swims, classes, and recreational swims create a thriving community atmosphere. Arguello at Anza, S.F. (415) 666-7014.

Sava Pool, near the Stonestown mall, is one of the few public pools with clear glass windows that stretch the length and height of one wall. With picnic tables and bushes, its patio area provides the day-at-the-park ambience you crave from your summer afternoon. Sava boasts the highest attendance, probably because of its ample parking, residential location, and the senior swim instructor's pleasantly contagious enthusiasm for its classes. The pool's only apparent shortcoming is the horribly Miami Vice-colored locker rooms, a painful mix of teal and flamingo pink. But perhaps that will put your mind in summer mode. 19th Ave. at Wawona, S.F. (415) 753-7000.