Concerned over the growing pollution of the rivers and streams of the north-west, a number of individuals in business and industry, public health and academia, met in Eugene, Oregon in May 1934 and established an organization to promote clear waters and public awareness regarding pollution problems. The first annual meeting of the Northwest Conference on Stream Pollution, as the organization was called, met in Lewiston, Idaho on May 15, 1935. At this first annual meeting, the members adopted a constitution and elected Carl E. Green president.

From its initial meeting in 1934 the organization has grown steadily from 20 members to over 1,200 in 1975. The organization has experienced a number of name changes during its history which indicated the changing attitudes and concerns toward the problem of pollution. At the first annual meeting in 1935, the membership changed the organizational name from the Northwest Conference on Stream Pollution to the Pacific Northwest Sewage Works Association. The scope of the organization broadened in 1951 when it became the Pacific Northwest Sewage and Industrial Waste Association. The final name change came at the annual meeting in 1959 when, in an attempt to stimulate public interest in the problems of pollution, the membership voted to change the organizational name to the Pacific Northwest Pollution Control Association (PNPCA).