William Isom Palmer was born in Cedar City, Utah, on May 14, 1907. He graduated with an associates degree from the Branch Agricultural College in Cedar City in 1927, and subsequently served a mission for The Church of Jesus-Christ of Latter-day Saints from 1927 to 1930 and married Virginia Corry in 1931. They had two children, Dr. W. Martin Palmer and Mrs. Robert W. Squire. Palmer attended Utah State Agricultural College in Logan, Utah, now Utah State University, starting in 1934 and graduated with a B.S. degree in agricultural economics in 1940.

From 1930-1934, Palmer worked for the Southern Utah Power Company. In 1935 he began working for the Department of Agriculture as project manager of the Widtsoe Land-Use Adjustment Project, which included supervising resettlement projects in the Southwest and working with county groups and colleges to establish soil conservation programs. From 1936-1938, Palmer was the regional chief of the Project Development and Land Acquisition Divisions for the Bureau of Agricultural Economies. From 1938-1944, he worked for the Soil Conservation Services in Colorado, Utah, Arizona, and New Mexico. In 1944 Palmer began work with the Bureau of Reclamation, where he became chief of the Division of Irrigation in 1958, and in 1959, he was made assistant commissioner. Palmer played a key role in the initial report of the Pacific Southwest Water Plan. He was later awarded the Distinguished Service Award by the Department of the Interior.

In 1964, at the request of Senator Carl Hayden (D-Arizona), Palmer transferred to the Senate to be a resource development advisor. The following year he transferred to the Agency for International Development to become the development finance officer for agriculture. In 1967, Palmer retired from federal employment and began working with the Ralph M. Parsons Company as chief agricultural economist. He was a lecturer at Utah State University in 1970, and in 1971 he began to work for the Council of United States Universities for Soil and Water Development in Arid and Sub-Humid Areas, and in January of 1972 he became the executive director. Also in 1972, Palmer began working with the Harza Engineering Company. In 1973 Palmer was elected chairman of the United States Committee on Irrigation, Drainage, and Flood Control. Palmer retired on July 1, 1973, but continued to provide consulting services to various countries and organizations. William I. Palmer died on November 20, 1982 in Saint George, Utah, at age 75.