They all agreed on the problem: It's too hard to move around Northern Virginia.

And as members of a special commission studying the state's transportation problems listened, the 300 people who went to the panel's hearing in Prince William County yesterday seemed to agree that higher taxes, toll roads and road bonds are inevitable.

"We had people tell us: 'Solve the road problem -- even if it costs money,' " said state Del. Gladys B. Keating (D-Fairfax). " 'We want to be able to move!' "

Keating, who suggested using hydrofoils to zip commuters along on the Potomac, was among more than 75 speakers -- including local officials, developers and civic activists -- who warned of economic chaos in the Washington suburbs because of poor roads.

State Sen. Clive L. DuVal II (D-Fairfax) shocked many when he suggested raising the state gasoline tax by 15 cents a gallon and urged a $1.5 billion bond issue to help pay for about $10 billion in critical transportation projects.

The commission, appointed by Gov. Gerald L. Baliles in January, is due to issue its report by Aug. 1, a month before a special session of the legislature is to convene in Richmond to deal with the report. The commission is widely seen as building public support for the higher taxes and costs that are almost certain to be recommended in the report.

Unless the General Assembly is willing to support such recommendations, "We're just spinning our wheels," DuVal said as he stood outside the hearing room. "I'll take the brunt of the criticism" for suggesting the taxes and the bonds, said DuVal, adding that the legislature is unlikely to accept his proposal, but would approve as much as a 5-cent-a-gallon increase if the commission backs the move.

Vivian E. Watts, a former Fairfax delegate and state secretary of transportation, declined to comment on DuVal's suggestions, saying it was too early to speculate about what the commission will do.

Baliles has suggested that the state scrap its decades-old "pay-as-you-go" system of funding roads in favor of considering a combination of higher gasoline taxes, bonds, toll roads and other funding measures.

"Unless we do something fairly dramatic, we're not going to even be able to stay in place," said William H. Leighty, deputy secretary of transportation.

Leighty said declining gasoline prices, conservation and increased maintenance for existing roads is eroding money available to spend each year for new construction.

Both former governors Charles S. Robb and A. Linwood Holton, members of the commission, attended yesterday's session at the Prince William County administrative offices.

While Holton, a Republican, sat through much of the hearing, Robb worked privately for several hours in the county prosecutor's office on a speech on Democratic Party politics he is to give today to the National Press Club in Washington.

Many local officials, including Arlington County Board Member John G. Milliken, urged the commission to promote a balanced transportation plan for Northern Virginia.

"It's essential for the state to be willing to do more" for Metro funding, said Milliken, touching on an issue that has been politically sensitive in the rest of the state. He said the state of Maryland funds about two-thirds of Metro's costs in suburban Washington while Virginia pays only about 10 percent.

Milliken, a Democratic candidate for Congress, and other speakers also pushed for an outer beltway and connector roads and state control of Dulles International and National airports, as well as a commuter rail project that would connect Fredericksburg and Manassas with Washington.

"The sleeper in here is the commuter rail," said state Sen. Richard Saslaw (D-Fairfax). "The potential benefit . . . is enormous."

The commission began a five-day series of hearings around the state in Charlottesville on Monday. The commission met in Richmond Tuesday and travels to Virginia Beach and Abingdon in far Southwest Virginia this week.

At every stop, the commission expects to be inundated with pleas for local highway consideration, said Watts. The former legislator from Annandale said the only surprise so far had been the discovery that most local government officials appear more than willing to share the costs of highway construction.