Green Line extension construction could start before end of 2017

The MBTA on November 17 is expected to pick a company to oversee the design and construction of the 4.7-mile Green Line extension through Somerville into Medford.

With the contract awarded, construction could start before the end of 2017 (preliminary work is already underway).

The extension is easily the most significant infrastructure project in the Boston region since the Big Dig. It involves not only the 4.7 miles, but seven new stations. The areas around each have already begun to feel the effects of a Green Line stop in terms of new development and rising rents and prices.

The MBTA has capped the contract to be awarded November 17 at $1.3 billion. The cost of the extension is estimated at $2.3 billion. The feds are putting up $1 billion, with the rest coming from the state as well as local governments.

If all goes according to current plans—a big if—service along the extension should start in 2021.

• Green Line extension expects green light from MBTA Friday [Globe]
• Somerville’s Union Square notches another change near future Green Line stop [Curbed Boston]
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