BOSTON -– Gov. Deval Patrick said Monday he’s pushing ahead with plans to build a commuter rail along the state’s south coast after the U.S. Army Corps of Engineers released its final environmental review of the proposal.

The announcement marks another milestone for the long-debated project, which still faces many hurdles, both practical and political.

Massachusetts Transportation Secretary Richard Davey called the report’s release “a critical step forward in obtaining the environmental clearances” needed to bring commuter rail service to south coast residents.

Davey said the state supports a proposed rail route that would take trains through Stoughton, Easton, Raynham and Taunton before branching off into two lines, one for Fall River and one for New Bedford. He said the route provides the best transportation, environmental and development benefits.

The state had weighed two other possible routes. One would use electric or diesel trains on an existing route through Attleboro. The other would create dedicated rapid bus lanes on Route 24 and portions of I-93.

Davey said once the environmental process is completed the state can begin developing final design plans for the project, which will provide a link from Boston to New Bedford and Fall River. The MBTA will take the lead in coming up with a final design.

Patrick, a Democrat who’s announced he’s not seeking a third term as governor, praised the release of the report.

“Residents of the south coast have been waiting for 20 years for a reliable transit system that connects conveniently to Boston and everything in between,” Patrick said in a written statement. “We are making it happen.”

Republican gubernatorial candidate Charlie Baker, however, said he remains skeptical about whether the state could get the necessary environmental permits and whether the project’s price tag is worth the investment.

“It’s a $2 billion project, and the big question in my mind — is that the best way to spend $2 billion” in southeastern Massachusetts, Baker said earlier this month.

The latest cost estimate for the project is $1.8 billion.

Democratic candidates for governor, including Attorney General Martha Coakley and state Treasurer Steven Grossman, are more supportive of the project.