Arlington County has hired a consultant to analyze the return on investment of the proposed Columbia Pike streetcar project, a study intended to update previous reports on the expected growth along the corridor in the coming years.

HR&A Advisors, which describes itself as a real estate, economic development and energy efficiency consulting firm that has worked on complex mixed-use projects around the world for the past 30 years, will be paid $97,000 and is expected to complete its work by December.

County manager Barbara Donnellan said in a news release that information such as new population projections and employment projections from various studies, as well as research from other local governments’ experience with streetcar and bus alternatives will be part of the study. Developers and Pike retailers also will be interviewed.

The Federal Transit Administration turned down Arlington’s application for money from its Small Starts program in April because federal officials doubted the streetcar project could be built for $250 million, the program’s funding limit. The county is considering whether to apply for a different FTA program which does not have that cost limitation.

County Board member Libby Garvey (D) had argued for an independent return on investment study most recently in December, after an election campaign in which the streetcar was a main issue. She said Friday that she does not consider the HR&A study to be independent.

The long-planned streetcar line, expected to run from the Skyline area of Fairfax to Pentagon City, then cross over to connect with another planned streetcar at the Crystal City Metro stop, does not rely solely on federal funds. Arlington officials expect to use $35 million from Virginia transportation coffers and $35 million from Fairfax County. Arlington’s $104 million contribution would come from a commercial real estate tax that can only be used for transportation.