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.
Why Restore a Tidal Marsh – http://restorecullinan.info/restore.htm
8/4/14 – Geofoam is being utilized underneath the slopes of the embankment to prevent future settlement of the roadway. The first of many deliveries arrived on site today. Foam will be placed in the ditch at the toe of the embankment. Learn more about geofoam and its application here.
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. This work will require the shoulder to be closed and will be ongoing for 2-3 months.
7/14/14 – Dredge material from the Mare Island Dry Dock is being placed inside Cullinan Ranch in order to raise site elevations so that it can support marsh vegetation. Over 80,000 CY of material is expected to be placed in the coming months. An clamshell offloader unloads barges into the site from Dutchman Slough.
7/10/14 – Phase III construction has been awarded and the contractor will be mobilizing on site by early August. Construction is anticipated to continue into January 2015 when levees will be breached and the site restored.