SPRINGFIELD – The City Council on Monday authorized spending $3.2 million toward the long-awaited, $75.6 million Union Station intermodal transportation project.

The funding was approved by unanimous vote, occurring as construction crews continue demolishing the deteriorated baggage building adjacent to the long-vacant station, helping to provide space for bus bays and a new parking garage, as key components of the project. .

The council vote authorized borrowing the $3.2 million, with that cost set to be covered by annual payments from MGM Springfield. MGM is building a $800 million casino project in the South End-downtown area, and is paying $500,000 a year for 15 years to the city, rather than rent space at Union Station, the two allowed options under MGM’s host community agreement.

As announced last week, the city intends to accelerate the redevelopment of Union Station, doing a complete build-out, rather than spread the project over two phases.

The funds from MGM and a new state MassWorks infrastructure grant of $4.2 million help accomplish that goal, officials said.

With the complete build-out, the parking garage will have 377 parking spaces on four floors, reflecting an expansion of 122 spaces, officials said. In addition, the added funds will help move forward with customized office space on the upper floors of the station, to expedite leasing of that space, officials said.

Kevin Kennedy, the city’s chief development officer, said last week that after decades of discussion, design and redesign, the city is committed to pushing forward on a “very difficult project” and will complete it.

The project is scheduled for completion by the fall of 2016.

City Councilor Kenneth Shea said the Union Station project will provide a vital link to other regions and cities, both north-south, and east-west, connecting Springfield to more economic opportunities.

He said it was an “easy vote” to support funds for the project.

Shea said he took part in a recent tour of rail stations in New Haven and Hartford, arranged by U.S. Rep. Richard E. Neal, D-Springfield, and said the tour stressed the need for adequate parking at rail stations.

Councilor Bud Williams said the casino is a “good start,” but the redevelopment of Union Station is going to bring the “ripple effect” for further economic development opportunities, and hopes will be among actors spurring people to move to Springfield.