The table below shows an abbreviated modern history of the Reserve. You can find a more detailed version on early history of the Reserve land and on the modern human use of the Reserve in the two documents listed below.

An Abbreviated Modern History of the Reserve



1904 Border Patrol was established to stem the flow of Chinese laborers who were entering the U.S. through Mexico.
1909 Initial development of “Imperial Beach,” a summer retreat for residents of Imperial Valley.
1910 An estimated 890,000 Mexicans crossed the border during the Mexican Revolution. As a result, U.S. troops were stationed at camps near the monument to help patrol the boundary.
1920s As Tijuana became a tourist Mecca, the popularity of horseracing grew in the area. Breeders and owners kept horses at stables in the Tijuana River Valley.
1929 The U.S. Eleventh Naval District began acquiring acreage just north of the border, calling it “Border Field.” It was used as a machine-gun range and airborne gunnery range.
1941 The U.S. Navy leased 245 acres along the border and established Border Field Auxiliary Landing Field — an operation that included thirty-five buildings, one barracks, a galley and a machine-gun range.
1955 The area just north of the estuary began operating as a helicopter landing field, and the home base for all helicopter squadrons of the Pacific Fleet.
1961 The Navy deactivated Border Field and transferred 377 acres to the Navy Electronics Laboratory for classified experimental work in fleet electronics.
1964 California voters approved money for Border Field’s acquisition as a state park. However, developers were lobbying the federal government and local landowners with a plan to create an upscale marina in the estuary instead.
1971 President Richard Nixon announced that Border Field would be developed for recreational use as part of his “Legacy of Parks” program. Three hundred seventy-two acres became part of Border Field State Park, preserving the southern flank of the estuary. Meanwhile, local biologists Joy Zedler and Paul Jorgensen, along with Dr. Mike McCoy, a wildlife veterinarian, began to organize local environmentalists and Imperial Beach residents to build government and public support for the estuary’s preservation.
1980 Residents of Imperial Beach voted in favor of the marina project. Nevertheless, that same year, the U.S. Fish and Wildlife Service purchased the northern 500 acres of the estuary from the Helix land company and established the Tijuana Slough National Wildlife Refuge.
1982 In spite of heated opposition from developers – the estuary (both State Park and National Wildlife Refuge land) became part of the U.S. Department of Commerce’s National Estuarine Sanctuary Program, and designated a National Estuarine Research Reserve.
2005 The Tijuana River National Estuarine Research Reserve is designated a “Wetland of International Importance” by the United Nation’s Ramsar Convention on Wetlands.