Boston Mayor Martin J. Walsh and Gov. Charlie Baker joined Boston University leaders for the groundbreaking of the second phase of the Commonwealth Avenue improvement project, which is aimed at making the busy Allston street safer for pedestrians and cyclists.

“This is good — the bike lanes and creating more dedicated bike lanes is something we have to do,” Walsh told the Herald after the event. “This is a big step and we have to continue to work to have more safe and dedicated pedestrian walkways and bike traffic lanes.”

The project calls for the creation of modified sidewalks and crosswalks and a curbed bike lane that will separate bike riders from motorists.

State Transportation Secretary Stephanie Pollack, who also attended the groundbreaking, said she hopes the changes to Comm. Ave. will serve as “a national model of the right way to do a street.”