Caltrans Adds Major Marsh Protections to Planned Hwy 37 Project

In response to public comments and receipt of a letter from the Fish and Wildlife Service of the Department of the Interior that identified 22 species of plants and animals needing protection, Caltrans has modified its plans for the reconstruction of Hwy. 37.

Among the concerns offered were:

• Project impacts on adjacent biological and water resources, including loss of wetlands and wildlife habitats due to proposed fill for road widening
• Long-term resilience of SR 37 due to sea-level rise
• Impacts of tolling on low-income individuals
• Bicycle access restrictions under some of the alternatives
• The desire for lengthening and widening of Tolay Creek Bridge to create restoration opportunities
• Climate targets and vehicles miles traveled

According to the revised EIR, adding marsh protection and enhancement to the plan is a major change. Strip Marsh East (SME) “will improve drainage, restore full tidal function, create new wetlands and other waters from uplands, create new emergent salt marsh habitat, and establish tidal channel and tidal flat habitat.”

The revised plan now includes the Strip Marsh East Enhancement (see map) and Tolay Creek Bridge Replacement: “Caltrans, in coordination with landowners, land managers, and environmental agencies with jurisdiction, will enhance approximately 600 acres of degraded salt marsh habitat in an approximately 1,400-acre area of the Refuge’s SME Unit. Marsh enhancement is anticipated to benefit salt marsh harvest mouse, fish species (including steelhead [Oncorhynchus mykiss], Chinook [Oncorhynchus tshawytscha], Delta Smelt [Hypomesus transpacificus], Longfin Smelt [Spirinchus thaleichthys], and Green Sturgeon [Acipenser medirostris]), Ridgway’s rail, California black rail, shorebirds, and other special-status species that require channelized marsh habitat. SME enhancement through creation of a new channelized network is anticipated to create up to approximately 17 acres of new wetlands and other waters from existing uplands at the Pond 1/1A intake channel berms; 230 acres new emergent salt marsh habitat, and 80 acres of channelized tidal waters, and restore tidal function to the SME interior. Caltrans will replace the existing Tolay Creek Bridge with a 365-foot-long, pile-supported bridge; and remove existing fill in the historic Tolay Creek channel to improve hydrology, increase tidal prism, and create new habitat for special-status species. Tolay Creek Bridge replacement is anticipated to create approximately 1 acre of new waters from existing uplands.”

The Project is currently funded through the Project approval and environmental document phase. The estimated cost of the Project as approved in 2023 was approximately $430 million (Preferred Alternative 3B). The SME enhancement work is budgeted at approximately $23 million (in addition to the above Project cost).

The entire revised EIR can be viewed here