In 1935, the Department of Fisheries and Wildlife was established with Roland Dimick as its only faculty member and researcher. Immediately, Dimick began conducting water pollution studies on the Willamette River, documenting significant fish kills in 1935 and 1936. In 1939, Gov. Charles Sprague requested a study of native oysters in Yaquina Bay. For this purpose, the Experiment Station built a small laboratory near the mouth of the estuary, the forerunner of the Hatfield Marine Science Center.
Water pollution research by Dimick and other AES scientists played a role in the 1950s and 1960s when state government agencies began a massive cleanup of the Willamette River. Much of this research coalesced into a multi-disciplinary “Stream Team” in the 1960s, whose work was central in the debate over how to manage streams to benefit native fish and in developing strategies for salmon survival in the Columbia River Basin.