CHICAGO (CBS) -  Union Station is getting a makeover, to the tune of $40 million.

The 85-year-old landmark train station is receiving major upgrades, including air conditioning. Passengers have long complained about how hot it gets in the Great Hall, which has not had air conditioning since the early 1960s.

“With air conditioning, the Great Hall will become a year-round event venue, generating increased rental income,” an Amtrak news release said.

Also as part of the upgrades, the amount of seating in general passenger lounges will be doubled, and more restrooms will be added.

The upgrades will also involve a broader redevelopment plan for the Union Station Headhouse Building, which includes the Great Hall. The commercial real estate firm Jones Lang LaSalle is conducting a feasibility study for uses for the rest of the building, according to a news release.

“Improvements to Amtrak Chicago Union Station are a top priority,” Thomas Carper, chairman of the Amtrak board of directors, said in a news release. “Illinois is a national leader for passenger rail, and its commitment to work with other Midwestern states to build a robust service network from Union Station will allow us to bring more travelers to and from Downtown Chicago.”

Gov. Pat Quinn and Amtrak announced the $40 million project on Monday. It is being funded through the Amtrak capital projects budget, and will support 100 construction jobs, according to the news release.

“This major construction project will put Illinoisans back to work and help Union Station give visitors to the city of Chicago a welcome befitting the Land of Lincoln,” Quinn said in the news release. “New high-speed passenger rail service will bring thousands of visitors to downtown Chicago, boosting our tourism industry and supporting Illinois’ continued economic recovery.”

Air conditioning in the Great Hall will resume by summer 2011. The old air conditioning system for the space was abandoned more than 40 years ago.

By the end of 2012, the north and south boarding lounges for both coach and business class train passengers will expand from 450 to 950 seats by moving the area for sleeping car passengers, according to the release. More restrooms will also be installed on the concourse, or track, level, which was last upgraded in 1991, the release said.

Passengers on long-distance, overnight trains will also have added space in the Metropolitan Lounge, which will gain nearly 50 seats. It will be moved into an area between the Concourse and the Great Hall, the release said.

As for the rest of the Headhouse, Amtrak and its Chicago Union Station Co. subsidiary are putting parts of it out for lease. Amtrak will also cut costs by moving its regional offices into the building from leased space south of the station, according to the release.

Union Station was designed by the legendary Daniel Burnham, and was completed in 1925.

On an average weekday, close to 140,000 passengers pass through Union Station.

An average of 55 Amtrak trains go in and out of Union Station every day. The station also serves 11 Metra lines.

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