This paper provides an overview of adult fish passage improvements built on tributaries of the Columbia River as a result of the Pacific Northwest Electrical Power Planning and Conservation Act of 1980. The vertical slot design was used at 21 of 27 sites where fishways were constructed between 1984 and 1990. Adult passage facilities are compared, and the suitability of each type is discussed relative to site constraints. Components of each fishway are described, along with discussions of functional requirements and references to design criteria. Design, operation, and maintenance lessons learned are described.