MGM wants to delay the opening of its planned $800 million resort casino in Springfield by a year because of the reconstruction of the Interstate 91 viaduct – an elevated portion of the highway that runs through downtown Springfield that provides the main conduit to bring customers to the casino from Hartford, Connecticut. It would also delay the creation of thousands of jobs. A one-year delay in the opening of the planned resort casino in western Massachusetts because of a major highway project will affect millions of dollars in payments and gambling revenue the state and city of Springfield are counting on.