Greater Bahia Expansion Project

Marin Audubon Society has purchased two large bayland parcels located between the Marin County Airport at Gnoss Field and the Rush Creek marsh in unincorporated Novato. The Leveroni family has owned the properties and maintained them in agriculture for many decades. Marin Audubon Society, in partnership with Marin Baylands Advocates, is raising funds to permanently protect these parcels.

The northern most property is an 153-acre parcel is adjacent to and east of the Gnoss Field Airport and south of the CA Department of Fish and Wildlife owned diked baylands that surrounds the airport on two sides. The southern parcel is 170.28-acres south of the  airport and north of  the Rush Creek and Cemetery Marshes. The property connects with the western Bahia restored tidal marsh hence our choice of name. A narrow waterway, Pinkston Slough (formerly Black John Slough), separates the two parcels.

The parcels are at the center of a corridor of tidal marshes along the Petaluma River that are largely in public ownership. The corridor extends from the Petaluma Marsh, an ancient marsh that is the largest tidal marsh in the state of California that has never been diked, to the mouth of the Petaluma River and south along Hamilton This strategic location enhances the ecological importance of the purchase and increases the potential to restore them to tidal marsh. The acquisition is also consistent with the Petaluma River Baylands Strategy, which recommended the acquisition and restoration of these parcels. Restoration of the sites to tidal marsh will fill a gap in the marsh corridor.

Purchase of the properties enables Marin Audubon to restore these diked baylands to tidal marsh habitat. Although there is no plan as of yet, we expect the restoration to include full tidal exchange and setback levees with ecotone slopes that support native-plant and provides cover habitat to protect endangered Ridgway’s Rails, California Black Rails and other species from predators, as well as nesting and foraging habitat for special status species, including San Pablo Song Sparrow and Salt Marsh Yellowthroat. Setback levees would also increase flood protection for the airport and developed properties along Binford Road. Marin Audubon is well equipped to undertake this restoration, having restored more than 500 acres of tidal marsh on baylands purchased under the Marin Baylands-Marin Audubon partnership.

The acquisition was completed on June 12, 2026. Now the planning to restore the diked lands to tidal marsh will begin and is expected to take about five years to complete. We will also begin a process to remove the property from the Williamson Act.

If you would like to contribute toward developing the restoration plan, send your donation check to: Marin Audubon Society , P.O. Box 599, Mill Valley, CA 94942

Mark it for the acquisition. Or donate through the Marin Audubon Society website here.