Brightwater served as the Casselberry family estate for almost seven decades. Winter Park architect James Gamble Rogers II designed the Colonial Revival house in 1951 at the request of his friend and fellow Illinois native Hibbard Casselberry, a major landowner, developer, and businessman who founded the City of Casselberry and served as its first mayor. Construction began in 1952 and finished later that year. Casselberry's second wife, Martha Norris Casselberry, named the house after the view of South Lake Triplet at sunrise and sunset from the waterfront lot. Rogers designed Brightwater with four bedrooms, four bathrooms, and 5729 square feet of living space over three floors on 8.63 acres. The family built a dock, and later added a swimming pool in 1961. Hibbard Casselberry died at Brightwater at age 76 on August 29, 1969.