State Route (SR) 37 Sears Point to Mare Island Improvement Project: Package 1, SR37/SR 121 Intersection and Tolay Creek Bridge Replacement Project (Project)(Cal

State Route (SR) 37 Sears Point to Mare Island Improvement Project: Package 1, SR37/SR 121 Intersection and Tolay Creek Bridge Replacement Project (Project)(Cal

The California Department of Fish and Wildlife (CDFW) has issued ITP No. 2081-2025-059-03 to the California Department of Transportation. The Project will replace the existing two lane bridge with a wider five lane structure and reconfigure the SR 37/SR 121 interchange to improve traffic flow, including shifting the eastbound lane drop about one mile east. The Project will widen SR 37 in both directions, replace the Tolay Creek Bridge with a much longer span to restore tidal habitat, and upgrade drainage, barriers, pavement, lighting, signage, and traffic monitoring systems. Construction will use temporary roadways, bridge crossings, creek diversion systems, staging areas, and containment systems. Retaining walls, an embankment confinement system, and wildlife benches under the bridge will support the roadway and enhance habitat connectivity. The Project is expected to result in incidental take of the following species protected under the California Endangered Species Act (CESA): longfin smelt (Spirinchus thaleichthys, threatened), California Ridgway’s rail (Rallus obsoletus obsoletus, endangered and fully protected), California black rail (Laterallus jamaicensis coturniculus, threatened and fully-protected), and salt marsh harvest mouse (Reithrodontomys raviventris, endangered and fully-protected) (collectively the Covered Species). The Project will result in impacts to 2.70 acres of Covered Species habitat including temporary impacts to 1.85 acres; the Project will permanently remove 0.85 acres of open water and brackish marsh habitat. For all Covered Species there is an overlap of 0.77 acres of permanent impacts and 1.41 acres of temporary impacts between species. The replacement of Tolay Creek Bridge will result in the creation of 1.13 acres of tidal waters (e.g., in-water and accreted marsh habitat) in the Tolay Creek channel by removing the existing 320-foot-wide embankment and constructing a new bridge spanning the entire increased channel width. The ITP referenced above as issued by CDFW, pursuant to Section 2081(b) of the Fish and Game Code and pursuant to Fish and Game Code section 2081.13 with respect to salt-marsh harvest mouse, California Ridgway’s rail, and California black rail. Fish and Game Code sections 3511 and 4700 prohibit the take of fully protected birds and mammals, respectively, except as provided by the Fish and Game Code. However, CDFW may authorize the incidental take of salt-marsh harvest mouse, California Ridgway’s rail, and California Black Rail resulting from impacts attributable to, or otherwise related to, the State Route (SR) 37 Sears Point to Mare Island Improvement Project: Package 1, SR37/SR 121 Intersection and Tolay Creek Bridge Replacement Project, if the conditions set forth in Fish and Game Code sections 2081.13, subdivisions (a)-(d) and 2081, subdivisions (b) and (c) are met. (See Assembly Bill No. 697 (stats. 2025).) The Permittee will permanently conserve 2.802 acres of high quality occupied Covered Species habitat that will include a monitoring program and an adaptive management plan, approved by CDFW to fully mitigate the impacts of the authorized take of the species.

Sonoma

Sonoma

Northern California, San Francisco Bay Area

Sonoma