Isabelle Webster Capps, 96, a Washington resident for more than 60 years who was active in service organizations, died Tuesday at the Towne House Health Center in Fort Wayne, Ind., following a stroke.

Mrs. Capps was born in Dixon, Ill., and grew up there and in Chicago. She attended the University of Chicago and moved to Washington in 1980 to work for the federal government. She worked first for the old Post Office Department and then for the Treasury.

In 1911 she married Stephen R. Capps, who became noted for his work on the Alaska branch of the U.S. Geological Survey. Mr. Capps died in 1949.

Mrs. Capps was a member of the board of the old Children's Protective Association, now part of Family and Child Service of Washington. She also was a member of the Eistophos, a women's scientific organization, the Seymour Club, a literary group, and the 20th Century Club. She did volunteer fund-raising for the old Community Chest, now the United Way.

She was a founding member of the Cleveland Park Congregational Church.

Mrs. Capps moved to Fort Wayne in 1973 to be near one of her children.

Survivors include two sons, Stephen R. Jr., of Fort Wayne, and Webster, of Kennebunk, Maine; two daughters, Louise Scranton of Altanta, and Mary Stelle of Tucson, Ariz.; 10 grandchildren and three great-grandchildren.