The Presidio in San Francisco is a National Historic Landmark transferred from the Department of Army to the U. S. National Park Service in 1994. It was the nation’s longest-operating military facility, having served under the flags of three nations. Crissy Field, part of the Presidio and on the waterfront east of the Golden Gate Bridge, was originally part of a large estuary. It was filled with debris from the 1906 San Francisco Earthquake, and was further degraded when it served as a site for the 1915 Panama International Exposition. Later, the Army located maintenance, engineering, and other operations there. It was also a dump for domestic waste and paved with asphalt and concrete.
Partners in the Crissy Field restoration needed to strike a balance between protecting cultural resources and restoring natural resources. Major resource challenges included removing more than 87,000 cubic yards of contaminated materials, crushing 75 acres of asphalt and concrete on site and using the aggregates as a foundation for walkways and bikeways, reconstructing the original dunes, creating a 22-acre tidal lagoon, and placing . ll from the lagoon to create a foundation for the restored Crissy air field. Partners would raise $34 million in non-federal money for the project.