Folder: S.F. Islands-Alcatraz-Prison.
Newscopy: "Marin commuters have been wondering what that huge tower is, rising on Alcatraz. Warden James Johnston explained today it's a super water tower. In it will be stored 250,000 gallons of fresh water, amplifying storage space of the island's reservoirs. It's part of new water system, which in turn is part of million-dollar construction program under way on 'The Rock.' The tower, 100 feet tall, will stand some 200 feet above sea level, making it one of the island's loftiest structures."