The county is in line for a grant from the Federal Highway Administration to begin a $17.5 million rehabilitation of the westernmost stretch of Sir Francis Drake Boulevard. The project will focus on 12 miles in Point Reyes National Seashore between Pierce Point Road and Chimney Rock and Lighthouse Roads—the only roadway to the peninsula, the lighthouse and several dairies and ranches. Currently, segments of the road vary in width and are prone to flooding, and the asphalt is “severely degraded,” an agreement signed by the county in October says. The roads will be repaved, newly signed and striped and expanded to a consistent 24-foot width. The flood-prone sections, nearly half a mile west of Home Ranch Road just before the entrance to Drakes Bay Oyster Farm, will also be raised one to four feet and shifted east so the road can pass over a hillside above high water. The $15 million from the F.H.A. will be the largest road maintenance grant the county has ever received. The county will also kick in $2 million and the National Park Service has set aside $400,000. The seashore may also delay expected repair work on Limantour Road to combine with this project and save on contracting costs. Environmental scoping will begin this month, the agreement stipulates, and the project is expected to be complete by December 2019. Ernest Klock, the principal civil engineer for Marin County Department of Public Works, said he is anticipating a Finding of No Significant Environmental Impact, but that federal agencies will be reaching out to community groups to solicit comments in the preparation of an environmental assessment.