Left. Swan Island, 1897. Courtesy of University of Texas Library. Right. Swan Island, 1965. Courtesy of the Oregonian. Note that in 1897 Swan Island was actually an Island. By the 1920s, dredging and soil disposal connected it to the mainland. Before 1935, the Port was responsible for dredging the Columbia and Willamette Rivers. The Port has owned seven dredges since 1898. The Tualitin, Willamette and Columbia were part of the dredging efforts at Swan Island.