At $286.7 million, a new stadium for D.C. United on Buzzard Point would be the most expensive Major League Soccer stadium ever built, according to a study commissioned by the D.C. Council, but could bring $109.4 million in economic benefits to the District.

The 406-page report, which can be viewed here, was performed by CSL International, Integra Realty Resources and the Robert Bobb Group, the consulting firm of former D.C. city manager Robert C. Bobb.

It aims to assess a deal proposed by D.C. Mayor Vincent C. Gray (D) and City Administrator Allen Lew in which the city would swap properties with developer Akridge and utility Pepco in order to assemble the land needed for the stadium to the team at no cost.

The team would then pay to build the stadium and receive a series of tax breaks worth around $50 million to lessen the cost of completing and operating the stadium.

D.C. Council Chairman Phil Mendelson delayed release of the 124-page study until Wednesday morning, the day after the election in which he and several other members of the council were on the ballot. Mendelson won re-election handily. A hearing on the report’s results is scheduled for noon Wednesday.

Among the report’s initial takeaways:

– The proposed stadium would cost an estimated $286.7 million, the priciest MLS stadium to date. The cost to the District is estimated at $131.1 million, or 46 percent of the total, though those costs could rise, potentially beyond a $150 million spending cap imposed by the District.

– Gray and Lew likely underestimated the values of properties they proposed trading away, and overvalued the properties on Buzzard Point the District would receive in return. The study’s authors say the net difference is $25.7 million, including an estimated $11.2 million under-valuing of the Reeves Center, the municipal building on U Street that Akridge would receive in the deal.

– Building the stadium, redeveloping the Reeves Center site and building a new municipal building in Ward 8, as Gray has proposed, would inject an estimated $2.6 billion into the District’s economy. About 1,683 full-time or equivalent jobs could be created.

– The stadium alone could produce $109.4 million in net fiscal benefits to the District from sales taxes, income taxes, property taxes, business franchise taxes and ticket fees over the course of the lease.

– Building a stadium on Buzzard Point is likely to accelerate economic development there. Without a stadium, the report suggests that little would get built there for between eight and 10 years.

Follow Jonathan O’Connell on Twitter: @oconnellpostbiz