By Judith Preieve
“Once eyed for thousands of homes, the recently restored Dutch Slough tidal marsh in east Contra Costa County is already flourishing as a new habitat for fish and wildlife, a living laboratory for scientists and one of the world’s strongest sinks for absorbing and storing carbon long-term.
“It’s taking in carbon at a rate compared to the top 1 percentile (of all ecosystems) in the world (annually),” said Katie Bandy, the department’s Dutch Slough Tidal Marsh Restoration project manager. “It’s taking in a lot more carbon than other land is producing.”
Scientists estimate that more than 350,000 acres of tule marsh once blanketed the area from Sacramento to Stockton, yet only 2% to 5% of those are left. European settlers moved here in the Gold Rush days and many hired Chinese immigrants to divert the waters and build levees for farming.
Because many of those “farming islands” have now sunk some 20 to 25 feet below sea level – too low for plants when the tides come in – there are fewer opportunities now to build tidal marshes, according to John Cain of River Partners, a nonprofit that works on large-scale habitat restoration projects.
Considered the project’s visionary, Cain got involved in promoting the wetland project in the late 1990s while working for the Natural Heritage Institute. Knowing Dutch Slough land was at the mouth of Marsh Creek, filled with mineral soils and clay, the restoration ecologist understood it had not sunk as low as some other areas and could be transformed into a tidal marsh.”