Virginia Transportation Secretary Sean T. Connaughton’s scheduled appearance Tuesday in front of the Prince William Board of County Supervisors underscores an important moment in the debate over a controversial parkway that would connect Prince William and Loudoun counties, observers say.

The Bi-County Parkway has divided elected officials in Prince William and Loudoun, with many raising concerns about the 10-mile road that would run through Civil War ground and Prince William’s protected Rural Crescent. The coming weeks are important for the future of the parkway, because it is unclear whether a future administration would embrace plans for the road, and state officials look for a major legal agreement to be completed before year’s end.

At Tuesday’s meeting, Connaughton, a former Republican supervisor from Prince William, will address some of his old colleagues. He is expected to present an overview of the Virginia Department of Transportation’s reasons for building the parkway and to answer supervisors’ questions.

State officials have said that the road is a key part of Virginia’s future transportation network and that it would help spark economic development in the growing north-south corridor.

Board Chairman Corey A. Stewart (R-At Large) said that although he expects most in the audience will be against the parkway, he is hoping that many just tuning in to the debate will understand that it is necessary to keep traffic moving and add jobs closer to where people live.

“Especially when you’re building a major new thoroughfare through private property, it is difficult,” Stewart, who supports the road, said. “What we have to try to do is keep the county forward-looking and thinking about the future. Every time you build a major new roadway, there’s going to be opposition.

“We have got to make clear that the status quo is not an option,” he said.

Supervisor Peter K. Candland (R-Gainesville) said that transportation officials should not move forward with the road until they have addressed the concerns of residents and elected officials. Emphasizing the Republican Party rift on this issue, six state GOP legislators have announced their opposition to the road.

“At some point, we continue to voice our concerns and either VDOT . . . continues to just ignore [them] . . . or slows things down and starts to address those concerns,” Candland said.

Mary Ann Ghadban, who lives near the site of the proposed road and has helped lead the opposition to it, has been critical of Connaughton and VDOT.

“It’s good for the supervisors to ask him important questions and see if he’ll tell the truth,” Ghadban said.

Connaughton did not respond to a request for comment. He was twice elected to Prince William’s chairman seat and served from 1999 to 2006. He left his second term early to head the U.S. Maritime Administration under President George W. Bush. Gov. Robert F. McDonnell (R) appointed him transportation secretary in 2009.

The parkway has proven more controversial in Prince William than Loudoun, where officials have, overall, been consistently supportive. Loudoun Board of Supervisors Chairman Scott K. York (R-At Large) said there is not much concern among local leaders over the continuing discussion in their neighboring county.

“Prince William is dealing with Prince William issues; Loudoun is dealing with Loudoun issues,” York said. “I hope that common sense in this will prevail.”

Some Prince William residents took the fight to Loudoun officials last month when the Leesburg Town Council took up a symbolic resolution to oppose the parkway. The town said that the state should not prioritize the parkway above other proposals and that it would not support the parkway as it is currently planned.

In June, when Leesburg leaders took up the issue the first time, York’s staff aide addressed the council on his behalf, reading a letter that cautioned town leaders to be careful about opposing the parkway. Even symbolic opposition could potentially affect whether the town’s other transportation priorities were funded, he warned.

The letter drew an indignant response from several council members and prompted Del. Timothy D. Hugo (R-Fairfax) to call for York’s resignation from the board of the Northern Virginia Transportation Authority.

Bill Card, chairman of the Republican Party committee in Prince William, said he thinks that VDOT officials should heed what skeptical residents and many Republicans are saying.

The road “doesn’t pass the smell test,” Card said.

Also, concerns about preserving the Manassas National Battlefield Park and a prized rural area are real, he said. “It goes beyond ‘not-in-my-backyard’,” Card said. He said many would support a similar project elsewhere.

“Mr. Connaughton ought to listen to them.”