Site History

Before Diking and Farming

The Hamilton Wetlands Restoration Project site was initially part baylands and part San Pablo Bay. During the period from 1853 to 1884, mining for gold in the Sierra Nevada foothills caused substantial amounts of sediment to enter into the Bay system, resulting in the build up of the shoreline on the eastern portion of the project site. Around the turn of the last century, the marsh lands were diked to accommodate dry-land farming.

The Hamilton Army Airfield

Army Airfield in 1935

Army Airfield in 1935

In July 1932, construction began on what is known as the Hamilton Army Airfield, named for Lt. Lloyd Hamilton, the first American pilot to fly with the Royal Flying Corps during World War I. Construction was completed in 1935, turning the site into a large enough base to accommodate four bomb squadrons and their personnel, as well as headquarters for the 1st Wing of the Army Air Corps – one of only three bases established for this purpose in the nation at the time.

The base played a significant role during World War II in training and national defense by serving as an overseas staging area. Hamilton Army Airfield’s strategic location in the Bay Area was an ideal point of departure for Pacific-bound air troops. The base’s strategic location also allowed crews to closely monitor the coast’s air and naval traffic.

After the Hamilton Army Airfield’s significant contributions to WWII, the base was reassigned several times until buildings and land were transferred to the Navy, Army and Coast Guard in 1985. For more information about its military history, visit:

Airfield active in the 70's

Airfield active in the 70’s

The airfield remained operational until 1974 and began a closure process under the Defense Base Realignment and Closure Act in 1988. The base was redeveloped following a 1996 Reuse Plan, the City of Novato’s Master Plan and subsequent plans and processes. Much of the base was converted to residential and commercial use, with a significant balance set aside for parks and open space. The area east of the former Hangars, including the Airfield tarmac and runway, was transferred to the State of California for eventual open space and wetland restoration purposes. And so in 1998, the United States Army Corps of Engineers, State Coastal Conservancy and the San Francisco Bay Conservation and Development Commission teamed up to address the technical aspects of the restoration and to determine how to best restore the wetland habitats on the former Airfield and North Antenna Field (north and east of the Airfield). Since 2001, the Corps and Conservancy have been working in partnership to construct site features of the new wetland, much of which is located on top of the old runway. Heavy construction on the Airfield was completed by 2013, and the Bayfront levee was breached to restore tidal action in April 2014. Restoration on the areas north of the Airfield, the Bel Marin Keys Unit V and North Antenna Field properties, is pending.