They keep waiting for their ships to come in : Commuters rock the boat as ferries run at capacity.

It is the state’s No. 1 tourist attraction and a vital highway link for 33,000 commuters a day--but the fanciful ferry boats of Washington are rolling under the crush-weight of their popularity.

One hour? Three hours? Five hours?

Those are the unpleasant waits that some visitors will have to endure this summer just to drive onto a ferry for a 20-minute, seven-mile crossing of Puget Sound and for the longer journey to the San Juan Islands northwest of Seattle. Some unprepared visitors might find themselves stranded overnight, sleeping in the back seat of their car on an island parking lot awaiting tomorrow’s boat.

“Ridership is growing by leaps and bounds every year. It’s almost frightening,” says Susan Harris-Heuther, spokeswoman for the ferries.

The 25 ocean-going boats of the Maritime Division of the Washington Transportation Department are the largest ferry fleet in the nation. And no doubt the busiest, too, with capacity to carry almost 2,500 cars and 30,000 people at a time. Last year, the total was 9 million cars and 21 million passengers.

During nearly a century of service and with minimal hype, the ferries have become the authentic symbol of Seattle. Forget rain--that old sop simply does not hold water. Rainfall is heavier in New York, Washington, D.C., Houston, and Cincinnati, to name some. And never mind the venerable Space Needle. Few people visit it twice. No, the symbol of Seattle--the place where locals and tourists come together and rarely leave disappointed--is the ferry boat.

“I don’t think you can come to this area and not be enchanted by a ferry ride,” says Jo Ann Young, a resident of Vashon Island and the chair of a commuter activist group, the Washington State Ferry Riders Coalition.

On a sunny summer day, the routes from the mainland stations in the vicinity of Seattle to the Olympic peninsula and the islands of the sound provide the vistas that give Washington its reputation for dazzling the senses--to the west the Olympic Mountains, to the east the Cascades and Mt. Rainer. The deep blue water is home to seals and orcas, or killer whales, and bald eagles sometimes soar overhead. The mournful wail of the ferry bugle reverberates across the water and into the high-rise canyons of downtown.

But today the system is in a box. And few people can even envision a way out.

Not only does peak tourist demand on weekends result in absurd delays, but now even the rush-hour commute has outstripped capacity for those who drive their cars aboard, although walk-on space is almost always available. Managers are seeking three new jumbo, 206-car ferries at a cost of $200 million. But the Legislature has balked.

What good will it do my constituents, inland lawmakers ask. And commuters lobby vigorously against raising the fare, which at 99 cents for a walk-on is less than for a Seattle bus ticket.

For its part, the government is sponsoring yet another study of whether to replace some ferries with bridges--an idea that has been circulating for a half-century without gaining enthusiasm. Opponents note that a ferry has never sunk in Washington--while two floating bridges have.

Meanwhile, some residents of smaller cities with ferry terminals oppose more boats, arguing that tourists already are too numerous and disruptive. The rhythms of entire dockside townships already are keyed to the landing and departure of ferries, whether it’s trying to cross Main Street against a tide of 200 cars or to get a seat in a local pizza parlor.

So for lack of a consensus, the lines and frustration grow.

Commuters have devised many strategies to cope. Some locals drive their cars to the docks just before going to bed and then walk home, securing a place in line for themselves when they get up in the morning. Many people are two-car commuters--one at each end of the ferry ride and then they just walk aboard. These strategies are not without hazards, however.

“There was a young man who was late one morning. He parked his car and came running madly down the gangway. But the ferry was off the dock and it was moving. People screamed at him. But he kept going. With tremendous determination, he made a mighty leap and just landed on the edge of the ferry boat.

“A deckhand looked down at him and asked: ‘Hey, what’s your hurry. We’re just pulling in.’ ”

Joyce Delbridge, a retired teacher who lives on Vashon Island, is talking about “Northwest Ferry Tales,” her second book about daily life on the boats.

“You put all these people on these wonderful boats, and all sorts of things happen.”