Margaret Cecilia Chalmers, a homemaker who organized a volunteer effort that helped repair damage in Patapsco State Park after Tropical Storm Agnes, died of Alzheimer's disease Dec. 4 at the Ginger Cove retirement community in Annapolis. The former Catonsville resident was 85.

Born Margaret Cecilia Strobel in Wilmington, Del., she was raised in Northeast Baltimore. After graduating from Eastern High School, she attended business school.

Mrs. Chalmers worked during the early 1960s as a medical secretary for Dr. John Healy, a Baltimore physician.

An active member and former president of the Rolling Hills Women's Club, Mrs. Chalmers helped coordinate a volunteer effort that removed storm debris after the devastating 1972 storm. She was recognized for her efforts by state officials for her work in establishing a network of organizations and some 5,000 volunteers to work in the state park, family members said.

Mrs. Chalmers was a communicant of Holy Family Roman Catholic Church in Davidsonville.

Services are private.

She is survived by her husband of 61 years, William E. Chalmers Sr., founder and retired president of Yankee Engineering Co.; a son, William E. Chalmers Jr. of Chester; four daughters, Kathleen Kondylas of Newburyport, Mass., Rita Collins of Trego, Mont., Margaret Wilson of Arlington, Va., and Jeannette Warner of Easton; a brother, Bernard Strobel of Windsor, Pa.; seven grandchildren; and 11 great-grandchildren.