Congress approved a federal spending bill Friday that includes $20 million for a planned link to a Marin County ferry terminal along a future passenger rail line.

Officials with the Sonoma-Marin Area Rail Transit Authority consider the 2.2-mile link from downtown San Rafael to the Larkspur ferry terminal a critical component of the rail service, which is set to debut in late 2016.

The $20 million in federal funding comes from President Barack Obama’s budget request of $353 million to fully fund nine projects in the Federal Transit Authority’s Small Starts program.

The federal money will be matched by $20 million derived from local bridge tolls.

The 2.2-mile Larkspur link would come online one year to 18 months after the passenger service starts, according to SMART officials. In the interim, rail passengers will be bused from San Rafael to the ferry terminal and vice versa.

You can reach Staff Writer Derek Moore at 521-5336 or On Twitter @deadlinederek.