Green Line Extension brings opportunities and challenges for Somerville's Union Square

On Monday morning, a train took its maiden voyage along the Green Line Extension to Union Square station in Somerville.

The Extension is a project years in the making. Current and former elected officials celebrated the feat Monday, but new transit brings both new opportunities and familiar problems — for every story about a better commute to the city, for example, there's a story about someone's rent going up.

We talk about these trade-offs and challenges with Zach Baum, president of the board for Union Square Main Streets, and co-owner of Bow Market, an outdoor mall in Union Square. Then, we turn to WBUR reporter Simón Rios for analysis.