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Base Summary

Base Mission and Use
With roots dating back to the mid-1800s, Naval Weapons Station Seal Beach Detachment Concord, CA was one of the oldest naval ordnance support bases on the Pacific coast. In 1857, the first ammunition magazine was completed at Mare Island Naval Shipyard, located 35 miles northeast of San Francisco, near the confluence of the San Joaquin and Sacramento Rivers in Suisun Bay. In 1942, the Navy built an annex to this magazine, located across the Sacramento River from Mare Island. This Annex was later renamed Naval Ammunition Depot, Port Chicago after a nearby town. In July 1944 the Depot was the scene of a large explosion which destroyed the original pier and several surrounding structures. A memorial now stands at that location. By April of 1945 three additional large piers and a number of ordnance storage magazines had been constructed on approximately 13,000 acres of land. The property was divided into two sections, a Tidal Area and an Inland Area.

The Detachment's primary purpose was the loading and unloading of large quantities of weapons and equipment from cargo and pre-positioning ships. This differs substantially from most other naval weapons stations and detachments, where weapons are loaded aboard combatants, amphibious vessels or replenishment ships one at a time or in very small groups.

Due to workload and budget reductions, Detachment Concord was placed into a reduced operational status beginning October 1, 1999. Port operations in the Tidal Area were assumed by the Department of the Army's Surface Deployment and Distribution Command (SDDC) under a use permit from the Navy.

BRAC 2005 Decision
The BRAC 2005 Commission Report, enacted on November 9th, 2005, recommended the operational closure of the Inland Area except such property and facilities as are necessary to support Army operations in the Tidal Area.  On October 1, 2008, the Navy transferred that area, along with the retained portion of the Inland Area, to the Army; now called "Military Ocean Terminal Concord".  On June 29, 2007, the Navy transferred 59 acres of Inland Area real property and housing facilities to the United States Coast Guard. The remaining 5,028 acres of the Inland Area was declared surplus in March 2007 and was operationally closed on September 30, 2008.

Current Status:
The Navy continues work under its environmental program to make the property environmentally suitable for transfer.

(Updated February 2023)

NWS Concord Conveyance Status
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