A view of Washington’s National Mall from the U.S. Marine Corps War Memorial in Arlington on Dec. 29. (Brendan Smialowski/AFP/Getty Images)

Stung by a year of voter frustration over county spending decisions, the incoming head of the Arlington County Board announced a new effort Thursday to seek community input on whether and where schools, fire stations and other civic infrastructure should be built as well as on how to retain parks and open space.

Mary H. Hynes (D) said she will appoint 20 residents to study and advise elected officials. She promised broad outreach countywide to “deeply engage as many people as are willing to be engaged with us.”

“I think our community is saying very clearly to us, ‘Figure this out together, these are generational investments — new buildings last 50 years, and where they go has impact,’ ” Hynes said in an interview before the board’s New Year’s Day meeting.

School Board members, who are also part of the outreach initiative, joined County Board members at the meeting.

The effort is an attempt to restore the “Arlington Way” of seeking consensus before major public projects are started, Hynes said. It is also aimed at addressing voter dissatisfaction that became apparent with last year’s election of board member John Vihstadt (I), a critic of how the board conducted business and the first non-Democrat to join the panel in 15 years.

Vihstadt’s victory in a special election last spring, and his reelection in November, was attributed in large part to community opposition to the Columbia Pike streetcar project, which Vihstadt made a central part of his campaign.

Hynes and then-Chairman Jay Fisette (D) abruptly canceled the streetcar project two weeks after the election. They said a once-strong community consensus had broken down, preventing the board from addressing other issues.

There had been other signs that Arlingtonians were growing skeptical of major public spending on capital projects. The county already had pulled back on two of the biggest examples of such projects — a million-dollar bus stop and the Long Bridge Park aquatics center — after public criticism.

Residents in 2014 also debated how to handle Arlington’s booming public school enrollment, whether a fire station should be built in North Arlington and if demands to use public land for affordable housing should preempt much-valued green space and parks. Residents said they didn’t know what standards county government staff was using to make recommendations to the board on those issues or how board decisions were made.

“We skipped an important conversation,” said Hynes,who described 2014 as the roughest of her 20 years in elected office. “This is an opportunity to step back and, with the help of a lot of people, decide where we go from here.”

She described the effort to generate community discussion as a “new chapter” in Arlington’s planning history.

In her address, she said that “2015 will be a year of change, as we deal with our growing population; a year of challenges as we continue to reinvigorate our economy; and a year of limits as we come to grips with the realities of our physical space.”

Forty years ago, the county agreed to focus density along its Metro corridors, preserving the single-family neighborhoods located beyond those corridors. That focus on transit-oriented development brought in thousands of residents and led to many millions in new tax revenue.

But federal budget cuts, a 20 percent office vacancy rate, soaring housing costs and more students needing more classrooms mean it’s time for the county to strategize about its next 40 years, Hynes said.

Board members typically press their own initiatives at the New Year’s Day meeting, and Thursday’s session was no exception.

Vice Chairman J. Walter Tejada (D) pledged to “redouble my unwavering commitment to supporting affordable housing and maintaining Arlington’s diversity.” Fisette said he would continue to push for environmentally responsible policies and called upon his colleagues to “model the respectfulness in light of our differences of opinion that we are asking of others.”

Vihstadt and Libby Garvey (D), the two members who have been most critical of board priorities and decisions, continued to suggest new ways of doing business.

Vihstadt urged changes including establishing a whistle-blower protection code; an independent internal auditor, and votes on all county contracts worth $1 million or more.

Garvey called for the board to reconsider its New Year’s Day meeting tradition, saying county employees who work to facilitate the session should have the day off.

Board members also promised to work on improving transit and development in the Columbia Pike area in the wake of the streetcar cancellation.

The four-year terms of Hynes and Tejada expire at the end of 2015. Tejada says he will run for reelection. But Hynes, who was on the School Board for 12 years before being elected to the County Board in 2007, said she would not decide whether to run again until February.

“Twenty years is a long time,” she said. “On the other hand, I have a tremendous amount of experience, some people trust me and I’m excited about what I’m launching. . . . But sometimes people stay too long. I’m still mulling.”