Massachusetts transportation officials are planning a $17.2 billion capital projects program within the next five years.

The Massachusetts Bay Transportation Authority (MBTA) will receive $8 billion of the proposed amount, money that will be spent to improve public and private transportation in the city. About $985 million will be used for track and other system upgrades, over $415 million for bridges and tunnels and $1.2 billion for the $2.3 billion Green Line extension that will expand light-rail transit service in the Boston area, according to the Lowell Sun.

In order to determine how the Green Line extension could boost future capacity, the MBTA has committed to a six-year, $35 million spend.

“We now have a pipeline of projects,” said MBTA General Manager Luis Ramirez, according to the Lowell Sun.

The project has been dragged on by numerous issues, including potential cost overruns which resulted in all the original contractors being fired. The extension is scheduled to be completed in 2021, but has not yet begun. Once completed, the 4.3-mile extension will provide residents of Cambridge, Somerville and Medford to light rail service to the city proper.

Even after initial cost increases in 2015 exceeding the MBTA’s budget by $1 billion and other hurdles, the projects will soon be underway.