Walking by the Waves : CITY SMART: How to thrive in the urban environment of Southern California : The longest stretch of public beach in L.A. County, from the Marina to Redondo, is the setting for soothing strolls by many, though most prefer the southern half.

The beach walker: thinker, dreamer, creature of habit.

Don Clarke is one. He is 64, a professional man, out strolling one recent morning in his orange shorts, T-shirt and ball cap. He’s got Rush Limbaugh on the headphones. Clarke’s routine is always the same: Limbaugh and a four-mile hike. He starts at one end of Hermosa Beach, goes south to the wall where the beach stops, then back again.

“I love the ocean . . . love to just walk along and watch the waves and walk out on the piers,” says Clarke, one of scores of walkers who have come to enjoy perhaps the longest uninterrupted stretch of public beach in Los Angeles County: more than eight sandy miles between King Harbor and Marina del Rey.

But few people trek all of it. In fact, Clarke drives down from El Segundo--near the north end--to walk in Hermosa. A vast majority of the walkers only exercise on the south half of the eight-mile stretch, disdaining the north.

Though connected, the two sections of beach are different worlds, offering unintended historical lessons about coastal planning--what went right, and what went wrong.

The beach to the south--spanning Hermosa and Manhattan Beach--is, to many tastes, an idyllic place, characterized by cafes, shops and beachfront bungalows. Each city has a fishing pier. There are pedestrian-only streets at every block, providing ready access to the sand. Paved paths along the beach make it easy for walkers, skaters and bicyclists to traverse the whole of both cities, a distance of four miles.

North of Manhattan, however, the scenery changes. There are no piers. Bungalows give way to beach-front industrial uses, including two electrical power plants, an oil tank farm and Los Angeles International Airport. Although the bike trail continues, a paved walking path does not, and few people on foot bother to make the trip.

“It’s a whole different ambience,” says Diane Loughbom, a Manhattan Beach resident who sees some advantage in the solitude that can be found at Dockweiler State Beach. But, like nearly everyone else, she takes her regular strolls at the south end. “There is just more interaction with other walkers, and so on, in Manhattan and Hermosa.”

On this weekday morning, with sun breaking through the clouds, Loughbom has been as far south as she is going--she turns around at the Hermosa Pier--and is on the way back to Manhattan. She is in good spirits. She says the walk gives her a chance to enjoy the architecture of the beach houses and their flowered gardens. She likes to see other regulars on the Strand, some of whom she has passed by for years.

“I just have to be in touch with the ocean, no matter what,” Loughbom says as a biker goes by in the opposite direction, crooning an unfamiliar tune. She laughs. “Every third person is singing out loud,” she says, exaggerating a bit. “And they’re sober. That tells you something.”

North of the Manhattan Beach Pier she veers inland, heading for home, leaving the walkway to others. Joseph Secan is here, just starting out. He has his own routine: an eight-mile round trip to Redondo Beach and back. Often, he stops for breakfast on the Redondo Pier. It is a ritual he has followed for 35 years.

“I’ve walked along here about 2,000 times,” he says. “But every time I walk, I find something interesting along the road.”

Susan Glasheen and Beverly Barrett are heading south. They like to go from Manhattan to Redondo--3 1/2 miles--to have lunch at a favorite restaurant. On the way back, they figure, they will burn off what they eat.

“We’re here for the workout,” Glasheen says, laughing.

A few people have come from miles away. Sarah Yi, 18, and Wendy Wenkel, 19, are straying off the walkway to hang out at a favorite coffee shop. The two best friends from Torrance started coming here a month ago, and now walk practically every day.

“It’s beautiful out here,” Yi says. “You just watch the people go by. . . . We love the beach.”

Built as resorts near the turn of the century, Hermosa and Manhattan were designed for enjoyment of the coast--and the towns try to keep it that way, said Maxine Rhyne, planning administrator of Manhattan. There are problems with summer traffic and parking--and some residents grumble about old bungalows giving way to three-story homes--but civic pride is high, borne out by property values.

Beachfront homes range from $700,000 to $3.7 million. Real estate agent Zoann McFarland, who has lived near the Strand for many years, loves the people-oriented, village-like atmosphere.

“If you go down there at 6 or 7 at night,” she says, “you’ll see literally hundreds of people walking the Strand and watching the sun go down.”

At the north end of Manhattan, the bungalows abruptly end.

By contrast, the four miles north of Manhattan Beach are devoted to far grittier and more practical purposes. Located along Dockweiler State Beach are the two hulking electrical power plants, oil tank farm, airport and Los Angeles’ Hyperion sewage treatment plant. Ballona Creek, which cuts off the beach at the south edge of Marina del Rey, is a discharge point for raw sewage when heavy rains cause the city’s sewage-treatment system to overflow.

Although most of the development is considered vital to residents, much of it was built decades ago--long before planners foresaw the emerging importance of the urban beachfront. The electrical power plants, for example, were built in the 1950s, one by the Los Angeles Department of Water and Power and the other by Southern California Edison Co. Constructing them by the sea enabled the agencies to tap ocean water as a cost-effective way of creating the steam that turns their massive turbines.

But the visual blight of the two plants helped give momentum to the 1972 California Coastal Act, which attempts to control coastal development. There have been no new energy plants approved on the beach in California since the law was enacted, said Jack Liebster, a spokesman for the state Coastal Commission.

The beach near the power plants and under the takeoff runway at LAX is wide, white, nearly deserted. A few who have found their way here are out-of-towners. Jim Silveira and Larry Hubbard, who stroll the beach and walk out on a short breakwater, are truckers from Dallas.

Manfred and Conni Rumi are tourists from Germany. They are ending a three-week tour by motor home, staying at an asphalt campground at Dockweiler. They think this beach is attractive enough, but say the water is no warmer than the North Sea.

“It’s the same--cold, cold, too cold,” Manfred says.

Up near Marina del Rey, the bikers and skaters go by at intervals. Bob Hufnagel, who lives in the Marina, is a fan of Dockweiler, simply because of the quiet.

“Most people go the other way,” he reasons. “That’s why I come this way--I want to avoid the crowds.”