In 1944 the United States acquired Water Island for $10,000. They immediately began construction of a defense installation called Fort Segarra which was intended to protect military installations on neighboring islands. The fort included plans for barracks, gun emplacements, watchtowers and underground bunkers; World War II ended before its completion. Transportation, water, sewage and power systems were established during military presence. The Army’s Chemical Warfare Division used sections of Water Island for several years as testing grounds for poisonous gases.
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