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



12/5/14 - Cullinan Ranch will be re introduced to tidal water for the first time in over 100 years. The event will take place on January 6, 2015. Water will be visible along the highway almost immediately...

11/24/14 - Phase III construction is nearing completion with all the internal site improvements complete. Some minor work on the accleration / deceleration lane remains. Phase IV which includes levee breaching and levee lowering is initiated and will continue until the end of January, 2015 ...

Traffic Alerts

No major traffic delays are anticipated at this time ...



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