An inventory of lakes and reservoirs of Oregon is essential for a complete evaluation of the total surface-water supply of the State and to provide a basis for answering questions about Oregon's lakes. Much of the information on lakes and reservoirs previously collected by Federal and State agencies has never been published. Those data were compiled and used as a basis for collecting additional information. This report provides information for use by city, county, and State planning groups as well as for sportsmen, tourists, and others interested in preserving the recreational value of Oregon's lakes.
Because of the large number of lakes and reservoirs in Oregon, a single report covering the State would be bulky. Therefore, the lake information is being issued in several volumes on a county or multicounty basis. Volume 1, released in 1973, covered Clatsop, Columbia, and Tillamook Counties; volume 2 (1974 included Benton, Lincoln, and Polk Counties; and volume 3 (1975) included Hood River, Multnomah, Washington, and Yamhill Counties. Clackamas County was selected for volume 4. (See figure 1.)
In addition to office compilation of existing data, each lake was visited. Most visits were made in summer or early fall when lakes were most accessible and when water temperature and biological activity were near maximum.
