Sir Francis Drake Blvd Road Rehabilitation Environmental Impact Report

Location

SFDB is an east -west arterial roadway connecting US Highway 101 in the eastern end of Marin County, California with State Highway 1 at the west end of the County. The portion of SFDB proposed to be rehabilitated is along the western portion of the roadway between Shafter Bridge and Platform Bridge Road. This portion of SFDB traverses Samuel P. Taylor State Park and a portion of the Golden Gate National Recreation Area (GGNRA). SFDB has a horizontal curvilinear alignment and generally parallels Lagunitas Creek that flows west to Tomales Bay.

Project Description

Sir Francis Drake Boulevard (SFDB) is an east-west arterial roadway connecting US Highway 101 in the eastern end of Marin County, California with State Highway 1 at the west end of the County. The portion of SFDB to be rehabilitated is along the western portion of the roadway between Shafter Bridge and Platform Bridge Road. This portion of SFDB traverses Samuel P. Taylor State Park and a portion of the Golden Gate National Recreation Area (GGNRA). SFDB has a horizontal curvilinear alignment and generally parallels Lagunitas Creek that flows west to Tomales Bay.

The roadway rehabilitation project approved by the Marin County Board of Supervisors is the Mitigated Roadway Alternative (Environmentally Superior Alternative) described in the Final EIR and consists of pavement rehabilitation, drainage improvements, pullout improvements, and slope repair. The proposed pavement rehabilitation is divided into two segments. Segment 1 (Shafter Bridge to Station 100+00) will be rehabilitated using the crack and seat technique that reuses the existing concrete as a base for overlay of new asphalt concrete; Segment 2 (Station 100+00 to Platform Bridge Road) will be rehabilitated by milling the existing roadway surface and applying an overlay of rubberized concrete. All existing culverts comprised of corrugated metallic or plastic, within the right-of-way, will be removed and replaced. Those portions of existing culverts outside of the right-of way will not be removed and replaced. Regularly spaced pullouts will be provided along the roadway and paved with permeable asphalt. The proposal is to sign the formalized pullouts as no-parking zones. Other areas along the roadway currently used as informal pullouts will be landscaped to prohibit their use as vehicle pullouts. The existing unstable slope at Station 270+00 will be repaired. The slope repair will require the removal of up to 8 trees. In addition, the proposed project includes improvements to the alignment and width of SFDB. The proposed project as designed would not require the removal of any other trees.