The Alcatraz Eagle sculptural bas relief is located above the central entrance of the south elevation of the main prison building on Alcatraz Island. The Eagle was part of the original plan for the prison, designed by Maj. Reuben B. Turner and built between 1910 and 1912. The bas relief has several layers of different colored paint. During the 1969-1971 Native American occupation of Alcatraz, the Eagle was further adorned with graffiti.
ARG Conservation Services (ARG/CS) was contracted in September 2007 to treat the crumbling masonry and peeling paint on the Eagle. In its recent untreated state, the monument was missing mortar in the joints between masonry units and missing sculptural surfaces from spalling and sugaring of exposed masonry. The layers of paint peeling off the bas relief allowed water to penetrate the terracotta, and were a visual hindrance to the aesthetic reading of the monument.
The main objective of the treatment was to prevent further deterioration. Goals of the treatment included re-pointing missing mortar joints, patching areas of masonry failure, consolidating historic and culturally significant paint layers, removing less significant flaking paint, coating surfaces to reduce water penetration, and touching up painted surfaces to improve reading of the sculpture.
Conservation Treatments and Stabilization
Parks Conservancy
San Francisco, California
Finishes, Sculptures