Cofferdam No. 2 from north bank of Allegheny River looking southwest. A cofferdam is a temporary structure created to expose areas that are normally underwater so that work, such as creating supports or repairs can be completed.
Pittsburgh City Photographer Collection, 1901-2002, AIS.1971.05, Archives Service Center, University of Pittsburgh
Waterworks--Pennsylvania--Pittsburgh--Design and construction.; Cofferdams--Pennsylvania--Pittsburgh--Design and construction.; Rivers--Pennsylvania--Pittsburgh.; Allegheny River (Pa. and N.Y.).; Lincoln-Lemington-Belmar (Pittsburgh, Pa.).
Public Domain - Anybody may use this photo for any purpose