Pool, Lock and Dam 5A aerials

Set of 3 composite black and white aerial photographs in unlabeled envelope. Images show a changing aerial view of Lock and Dam 5A and Pool 5A on the Mississippi River, 1951 to 1973. Size and shape of composites are irregular. Creator likely the U.S. government, or the USGS. Part of the Cal R. Fremling collection. These items were not digitized.https://openriver.winona.edu/calfremlingphotographs/1039/thumbnail.jp