When the Morrissette family moved onto Clipper Drive in Fairfax Station 11 years ago, the tranquil county park across the street was the bonus. The park offered fishing, golfing and a playground, luring Jacqueline and Arthur Morrissette and their three children into the lush 889 acres like a call from the wild.

But over the years, an explosion of residential and commercial development has brought tens of thousands of newcomers to Fairfax County and its parks, transforming forever the Morrissettes' idyllic setting by Burke Lake Park.

Now the Morrissettes pray for rain on some nice spring weekends. They want to stem the flow of visitors who drive cars over their front lawn, toss trash and Frisbees, and urinate on their pine trees when the gates to the overcrowded park are closed.

"Our neighborhood has become an extension of the park. We're getting the overflow," Jacqueline Morrissette said. "Every year we see more and more people out here. It's unfortunate the park can't handle the number of people."

Though all parks aren't overrun, park officials, environmentalists and residents report that parkland in the Washington area is increasingly under the squeeze of the development boom.

Officials attribute the demand to a growing population, a shifting leisure life style that has placed an extraordinary demand on recreational fields, and a dwindling amount of large and available chunks of land.

"With the speed {at which} the growth has taken place, we're having some problem in keeping up with public service," said Joseph Downs, director of the Fairfax County Park Authority. "The county is adding 25,000 people a year and we're responsible with providing these recreational facilities to go with it. It keeps us moving to keep up with the rate of growth."

In a broad sense, the situation presents a contradiction in the entire concept of parks. "If you end up with a park just as crowded as rush-hour traffic, the parks aren't going to serve their purpose," said Destry Jarvis, vice president of the National Parks and Conservation Association in Washington.

Park officials note that despite the crowds, portions of the parks may be unused. The parking crunch, they say, is the most visible symptom of parks under stress, with visitors congregating in picnicking, boating and refreshment areas.

Park officials say the most congested times tend to be in the spring and after Labor Day.

The situation at Burke Lake Park in south central Fairfax provides an extreme example, but is not unique.

On a recent Sunday afternoon, a large sign just off the turnoff from Georgetown Pike announced that Great Falls Park in northern Fairfax was full. The 600 parking spaces were taken. Thirty minutes passed before a motorist in the line of rumbling cars reached the entryway to the 800-acre national park, where the rushing Potomac River spills over steep, jagged rocks.

A uniformed park officer, who walked from car to car, told impatient motorists that their admission would be on a "one-car in, one-car out" basis.

The visitors don't like waiting. Some throw fits, said Great Falls Park site manager Dwight Madison. Others leave in a huff.

"We really don't have any choice," Madison said. "The only thing we can do is to allow them to come in when we have parking available. This way, we can protect the resources."

The main priority of national parks such as Great Falls is preservation, while recreational activities are generally the top priority of city, county and regional parks.

But for all of these park systems, the situation is similar, with most in the Washington area reporting a rise in attendance in recent years.

Great Falls Park, for example, saw a jump in attendance from about 300,000 visitors in 1980 to 576,000 in 1986, according to a park manager. Among the county's parks, Burke Lake Park attendance increased from 386,050 in fiscal 1981 to 477,144 in fiscal 1986, and attendance at Wakefield Recreation Center in northern Fairfax soared from 194,841 in 1981 to 493,639 last year, park authority officials said.

The Washington and Old Dominion Railroad Regional Park, a hiking and biking trail that cuts a swath from Alexandria to Purcellville, handled a few hundred visitors a decade ago, but now carries more than 1 million hikers and bikers a year.

"The use is exceeding all the expectations that we anticipated," said Darrell Winslow, executive director of the Northern Virginia Regional Park Authority, which has 16 parks on more than 9,000 acres in six jurisdictions.

Montgomery County parks have seen a similar rise in attendance. In a special survey, the number of park users at Rock Creek Park rose 87 percent, from 121 in 1981 to 226 users observed per survey visit in 1985. At Wheaton Regional Park, the users rose 17 percent from 471 per survey visit in 1981 to 552 in 1985.

"Certainly, as the population increases, we have an increasing demand for parks," said Tanya Schmieler, a planner with the Montgomery County Parks Department, who cited the rapidly developing I-270 and Rte. 29 corridors as two areas with particular needs for local and regional parks.

More than anything else, park officials said they have been taken aback by the heightened demand for playing fields. In Montgomery, for example, the use of local ball fields has increased significantly, accounting for 41 percent of all local park use in 1985, according to a survey.

In Fairfax, which has evolved in two decades from a country crossroads to a thriving economic center, the popularity of active sports has come with the influx of corporations, new families and a stabilizing population.

"You've got a new breed of people here now. Some people call them yuppies. Some people call them anything they want," said Fred Crabtree, a longtime park authority member. "The young people coming into the county now are demanding facilities. They need them. They want them."

But it is not only the yuppies who are filling up the ball fields. It is also the industrial leagues, the youth and women's teams, and the senior citizens.

The problem of field availability has become so severe for the Fairfax County Adult Softball Council, the county's largest independent softball program, that, for the first time, next year it will limit the number of softball teams it will allow to 900.

The council's night softball games begin as early as 6:20 p.m. and finish as late as 11.

"In order to let everybody play, we play less," said Jim Minarik, who coordinates the council's industrial teams and works for a Tysons Corner advertising firm. "Everybody is using every field, every available moment."

Bright and early last Wednesday morning, the senior men's softball league was wrapping up its final game of the season on the diamond at Wakefield Park on Braddock Road.

The senior men play "slow pitch" softball mostly on weekday mornings to make room for the younger teams that pack the fields at night.

The players, whose ages start at 50, were hooting, diving for bases and yelling "Way to go" to triumphant players.

"We've got guys as old as 80 out here," said Russ Reber, 65, the tournament coordinator and a pitcher.

When the senior men's league began eight years ago, Reber said, about 20 men showed up to play. Today, the league has 265 members.

Officials with county and regional park systems said they are working vigorously to accommodate the suburban population's park needs, planning playing fields, building recreation centers and cutting hiking and biking trails.

In Fairfax, park authority officials are reviewing whether to recommend a $50 million bond referendum next year for park needs. About $34 million of park projects are under construction, including four recreation centers and additions to two centers.

Montgomery officials said they annually receive funding of between $1.5 million and $3.5 million for parkland acquisition, and another $8 million to $10 million for development of parkland.

In Loudoun County, board supervisors last month approved an ambitious $35 million project to address the park needs over the next decade as the county prepares for its predicted rapid growth.

"For many of us, the rate of development has left us with a high degree of uncertainty," said Frank Raflo, a retired Loudoun County board supervisor. "The general feeling in the county is of being overwhelmed by the magnitude of growth hitting us and challenged to continue the quality of life that made Loudoun attract us here in the first place."

But in counties where development is peaking, such as Fairfax, some say the challenge for the future will be in land acquisition, where county officials concede they have lagged in recent years.

In a county where it is not uncommon for land to sell at $100,000 per acre, "We're just priced out of the market on big tracts. That's all there is to it," said Crabtree of the Fairfax park authority. The authority spends most of its funds on parkland development, for such things as recreational facilities.

As in Montgomery, Fairfax officials said a recent trend has been to trade higher density levels for development in exchange for a portion of land for park use.

But some complain that the county has been timid in extracting desirable acreage from developers. And with transportation and roads standing out as hot issues, they worry that parks and open space are not high on the list of county priorities.

"We've got to snap up the land while we can still afford any of it," said Jean R. Packard, a prominent Fairfax civic leader and former chairman of the Board of Supervisors. "The longer we wait to acquire the land, the more expensive it is going to be."