There is a stretch of shoreline in Marin County, California, that used to be a runway. Today, herons stand where fighter planes once landed. It took engineers more than ten years, millions of tons of harbor mud, and one deliberate breach in the levee to make this happen. The story matters beyond California. A peer-reviewed study published in PLOS ONE found that West Coast estuaries in the United States have lost about 85 percent of their original tidal wetlands to development and diking, with San Francisco Bay among the hardest hit. Hamilton is one way of clawing a little bit of that loss back.
From marshland to military runway, and back again
The site used to be a typical tidal marsh at the fringe of San Francisco Bay. The land was first diked off around the turn of the 20th century to make way for farming, and the U.S. Army later drained it further in 1930, constructed dikes to prevent tidal flooding, and built an airport known as the Hamilton Army Airfield, according to the project history recorded by Environmental Science Associates, the design consultant responsible for its restoration. The base operated for many years before being closed in 1988.
