• rotate01
    Sunrise over Vallejo and Mt. Diablo as viewed from Cullinan Ranch
  • rotate02
    American Avocets feed in shallow tidal waters
  • rotate03
    Recently restored tidal marsh in the San Francisco Bay
  • rotate04
    Sandpipers take flight in a tidal lagoon
  • rotate06
    A quiet slough in the Napa Sonoma Marsh
  • rotate05
    Tidal marsh transitions to open water in the San Pablo Bay NWR



8/4/14 - Geofoam is being utilized underneath the slopes of the embankment to prevent future settlement of the roadway...

7/28/14 - The contractor has mobilized on site and will begin stripping the highway embankment of existing vegetation and cleaning the ditch at the toe...

Traffic Alerts

A planned shoulder closure on Westbound 37...

Nightime stoppage of traffic will be required for placement of K-rail...



Cullinan Ranch is situated in the Napa River delta and was once a network of deep water channels and vegetated marsh plain. A century of active farming has caused the land to sink as the rich organic soils of the marsh dried out, oxidized and literally blew away in the wind. Currently the site has subsided some 6 feet and is below mean sea level. Reintroducing tidal flows into the site will initially create open water habitat, but sediment suspended in the fresh water flows of the Napa and Sacramento-San Joaquin Rivers will deposit inside the site and slowly build up to where vegetation can colonize. This process - to restore to a mature tidal marsh - is estimated to take close to 60 years depending on sediment availability and the rate of sea level rise. A great article published by Bay Nature Magazine discusses the broader picture of restoration in the San Pablo Bay.

Major project elements of the restoration include:

  • Construction of a levee to protect low lying portions of Highway 37
  • Erosion protection on the slopes of the highway embankment
  • Improvements to access the public parking lot at Pond 1 from the highway
  • Public use elements including trails, a fishing pier and a kayak launching dock
  • Breaching and lowering of tidal levees

Construction began in Fall 2011 and is expected to be complete in January, 2014. Explore this site some more to learn about the:

Site History

Project Goals and Objectives

Construction Activities and Photos

Benefits of Tidal Marsh Restoration

News and Traffic Alerts

  • An aerial view of the old ranching homestead site and future location of a breach
  • A remnant slough inside Cullinan Ranch was used as a drainage ditch when it was farmed
  • South Slough borders the site's northern perimeter
  • At high tide, subsidence is clearly visibile inside Cullinan Ranch
  • San Pablo Baylands