Wolcott E. Lay, a Baltimore native who worked for various agencies of the federal government for the 30 years prior to his retirement in 1964, died Friday at the Winchester Memorial Hospital of congestive heart failure. He was 74.

Mr. Lay attended Rice University, in Houston, Tex., and graduated from Providence College, in Providence, R.I. He was also the holder of a B.S. degree from the old Columbus Business College, now part of Catholic University.

Mr. Lay entered federal service with the WPA during the Depression and went on to serve with the Department of the Interior's Bureau of Reclamation and the Agency for International Development. As an AID employee, he served in Thailand, Ghana and the Malagasay Republic.

During the 30 years he lived in Dunn Loring, Va., prior to his moving to Winchester 13 years ago, Mr. Lay was a founder and member of the Dunn Loring Fire Department and was active in the Boy Scouts and several gardening organizations.

Mr. Lay is survived by his wife, Katherine, of the home in Winchester; seven sons, Wolcott E. Jr., of Manassas, Richard D., of Vienna, Daniel H., of Beaver Falls, Pa., Charles Francis, of McLean, James Dominic, of the Dominican Republic, John C., of McLean and Donald C., of Fairfax.

He also is survived by a daughter, Dorothy R. Lay, of Knoxville, Tenn.; a stepson, Robert Rupert, of Virginia Beach; a stepdaughter, Angie Rupert, also of Virginia Beach; a brother, Thomas W. Lay, of Greensboro, N.C.; and 23 grandchildren.