The Power House is an electrical supply building on the northwest coast of

Alcatraz Island Alcatraz Island () is a small island in San Francisco Bay, offshore from San Francisco, California, United States. The island was developed in the mid-19th century with facilities for a lighthouse, a military fortification, and a military pris ...

, off the coast of

San Francisco San Francisco (; Spanish language, Spanish for "Francis of Assisi, Saint Francis"), officially the City and County of San Francisco, is the commercial, financial, and cultural center of Northern California. The city proper is the List of Ca ...

, USA. It was constructed in 1939 for $186,000 as part of a $1.1 million modernization scheme which also included the

water tower A water tower is an elevated structure supporting a water tank constructed at a height sufficient to pressurize a water distribution system, distribution system for potable water, and to provide emergency storage for fire protection. Water towe ...

New Industries Building The New Industries Building is a building on the western end of Alcatraz Island off the coast of San Francisco, United States. It was constructed in 1939 for $186,000 as part of a $1.1 million modernization scheme which also included the water to ...

, officers quarters and remodeling of the D-block. The white powerhouse smokestack and lighthouse were said to give an "appearance of a ship's mast on either side of the island". "A Warning. Keep Off. Only Government permitted within 200 yards" sign lay in front of the powerhouse to deter people landing on the island at the point. Alcatraz aerial

Between 1939 and 1963 it supplied power to the Federal Penitentiary and other buildings on the island. The powerhouse had a tower duty station which was guarded with a "30-caliber Winchester rifle with 50 rounds of ammunition, a Colt .45 semiautomatic pistol with three seven-round magazines, three gas grenades, and a gas mask."

References

{{Alcatraz Island Alcatraz Island 1939 establishments in California