The 1876 Boston Park Commissioners' master plan included a waterfront park in South Boston connected to Franklin Park (RX28) by parkways. Forming a crescent looking out to Boston Harbor, Marine Park became the first element of this scheme to be developed. Frederick Law Olmsted published a preliminary plan for Pleasure Bay (his name for Marine Park) in 1883, showing a wooden pier at the southern end and a tree-lined promenade crossing a causeway to Fort Independence (SB21) on Castle Island. A modified version of this plan was slowly constructed; relatively little of the initial design survives. Connecting this aquatic park into the municipal system were two parkways, the Strandway (beginning at Marine Park) and the Dorchesterway (connecting along Columbia Road to Edward Everett Square in Dorchester) built along the shore of Dorchester Bay and beyond, beginning in 1889. Completion of the park stimulated construction along its northern edge of Classical Revival three-deckers and shingled single-family houses. Along the water side of the Strandway (later named the William J. Day Boulevard), the city and private organizations constructed facilities for bathing and sailing. In 1899, wooden clubhouses (all NR pending) were built for the Boston Harbor Yacht Club (1805 William J. Day Boulevard), the Columbia Yacht Club (J. O'Brien, 1829 William J. Day Boulevard), the South Boston Yacht Club (Maginnis, Walsh and Sullivan, 1849 William J. Day Boulevard), and the Puritan Canoe Club (A. C. Fernald, 1819 William J. Day Boulevard). The city built the L Street Bathhouse (1930–1931, Gray and Hefernan, 1663–1665 William J. Day Boulevard), a low yellow brick structure with Art Deco detailing that replaced two earlier wooden bathhouses. The annual winter swim of the L Street Brownies occurs here.

A former member of the Olmsted office, Arthur A. Shurcliff designed Columbus Park beginning in 1916 near the connection between the Strandway and the Dorchesterway. This one-hundred-acre park culminated Mayor James Michael Curley's efforts to capitalize on the recreational opportunities of Dorchester Bay. In 1924, the Columbus Park Bathhouse (H. H. Atwood, architect; A. A. Shurcliff, landscape architect, 165 The Strandway), a red brick hipped-roof structure, was built to accommodate 2,200 bathers; the bathhouse was later renamed the Carson Beach Bathhouse, the result of a competitive naming race won by the Carson Street Swim Club of Dorchester.