Arlington plans to build a 4.9 mile streetcar line that will run along Columbia Pike. (Photo by Joseph Victor Stefanchik for The Washington Post) (Joseph Victor Stefanchik/For The Washington Post)

After a relatively quiet summer, the public debate over the Columbia Pike and Crystal City streetcar projects is likely to rev up again Tuesday as the Arlington County Board votes on a $26 million engineering and design contract for the 7.4-mile system and an $5.6 million contract for related street improvements.

The board has split 3-2 over whether to support the $333 million project ever since streetcar skeptic John Vihstadt (I) was elected to a vacant seat on the board in April, defeating Democrat Alan Howze.

Vihstadt and other opponents say the streetcar is too expensive and residents could be equally well-served by bus rapid-transit. Streetcar supporters, including County Board chairman Jay Fisette (D), say the new transit system is needed to keep traffic moving in an area where thousands more residents are expected to live and work in the next 30 years.

Candidates for General Assembly and Congress called for an advisory public referendum on the streetcar this past spring, but the County Board rejected that request in June. The board voted in favor of the streetcar project in 2009 and 2012, and the state is willing to pay half the cost of building it.

In anticipation of Tuesday night’s board vote, Fisette and transportation chief Dennis Leach held an online town hall last week to discuss the benefits of building new transit infrastructure in the busy south county. One hundred and eleven people tuned in.

“We are leveraging the streetcar to preserve diversity and affordability with no net loss of affordable housing,” Fisette said during a slide show presentation that combines the Columbia Pike project with the once-separate Crystal City project. “Many of the businesses and buildings relocated there because they new a streetcar was coming ... We paid a lot more money in the 1970s to put Metro under Wilson Boulevard. Think of that return on investment. I see this as another bold but important decision.”

Leach urged residents to consider the long-term vision. “If we don’t invest, if we don’t give people better travel options, they will choose to drive,” he said.

The town hall was part of a public relations campaign the county launched this summer to promote the streetcar project. The board has hired a management team for $7 million to $8 million to oversee the project for the first year of what’s expected to be a multi-year contract.

Tuesday night, the board will vote on a recommendation by the county transportation department to award the first major streetcar contract to HDR Engineering Inc. The New Jersey-based firm did planning and design work on transit systems in Tucson and New Orleans, and helped manage the construction and design of the D.C. streetcar project. The second award, for street improvements, would go to Kimley-Horn and Associates, which already has worked on the first phase of the project.

Preliminary engineering is expected to take about 18 months. Construction would not begin until fall 2017, with operations estimated to start in 2020.

The Columbia Pike streetcar line, which is planned to run from the Skyline area of Fairfax County, east along Columbia Pike to Pentagon City and then connect to the Crystal City Metro stop, has been discussed for more than a decade. The state earlier this year agreed to cover about half the cost of the Columbia Pike line. Regional transportation funds, which come from Arlington’s portion of the new Virginia fuel taxes, will cover 24 percent more and a commercial real estate tax, which can be used only for new transportation projects, covers the rest. Fairfax County will reimburse Arlington 20 percent of its costs, because the streetcar will have at least three stops in Fairfax.

The Crystal City to Potomac Yard streetcar line will be funded separately but is now part of Arlington’s pitch for a unified transit system that fills in areas unserved by Metrorail. It’s expected to run from the Metro stop to the Alexandria city line, where a rapid-transit bus corridor will connect and take passengers to the city’s Braddock Road Metro stop.

State funds will cover 25 percent of the cost of the Crystal City streetcar, regional transit funds will cover 11 percent and the commercial real estate tax will cover 46 percent. The remainder of the money will come from a Crystal City infrastructure fund that will come from property taxes on office buildings in the area formerly occupied by the federal government.