Concrete Waves: Chicago’s Twin West Side Natatoria
by guest author Nate Lielasus
The roof of the Ida Crown Natatorium in Eckhart Park is a wave of concrete about to crash onto the shore of Chicago Avenue. Slightly older than its twin in Harrison Park, at 18th and Wood Streets, the Eckhart Park Natatorium was constructed in 1961. The two Natatoria were built from a design by the Stanley Engineering Company. Although Marvin Werner was the principal architect, Dimitri Nesterenko, the structural engineer, was responsible for the dramatic roof canopy.
The simple, elegant design uses a bold clear-span structure to create a column-free interior space for the pool and deck. Four massive concrete ribs, spaced at 24′ intervals, spring from subterranean abutments 160′ apart. Thin shell roof slabs span between the bottoms of the arched ribs to create a smooth ceiling on the interior that vaults high above swimmers splashing in the water below. The ribs are exposed on the exterior, revealing to the passerby the dominant structural system of the building
The 260 cubic yards of concrete required for each monolithic roof structure were poured in a single day. Construction for the rest of the buildings had to wait until the roof was cast and the concrete had cured. Once the forest of scaffolding was removed and the formwork peeled away, the Paschen Construction Company moved on to excavating the pools and detailing the glass window walls.
Originally the formwork and centering from Eckhart Park were going to be reused to cast the roof structure of the twin Harrison Park Natatorium. However, unstable limestone slurry and earth fill below the ground at Harrison Park, relics of an abandoned quarry, caused construction delays which prevented reuse of the forms.
The design of the natatoria was meant to blend interior and exterior so the pools could be used year round but, in the summer, have some of the appeal of an out-of-doors pool. Under the thin shell roofs, the volume of each building is completely wrapped in a window wall except where low bands of brick wall, with window above, bracket the corners and one short side. The glass window walls make the buildings very transparent and allow light to flood inside. The window walls along one side of each pool has a series of large glass panels. These panels can be slid aside in warmer months to open up the buildings to the outside and provide direct access to a forty foot deep sun deck which wraps around two sides of the buildings in an “L “configuration. Above these sliding panels red, green, yellow and blue panes sprinkled among the clear glazing add cheerful spots of color.
The natatoria were built adjacent to existing park field houses, both designed by William Carbys Zimmerman (1859-1932), a Chicago architect who designed many park district buildings in the early 20th century. One-story vestibules with screen walls of stacked brick create indoor links to these field houses. These vestibules are also entry lobbies for the pools, with access to the pool area from the adjacent field houses as well as outside.
According to an article in the Chicago Daily Tribune on August 8, 1961, Mayor Richard J. Daley himself attended the dedication of the Ida Crown Natatorium in Eckhart Park, along with the commissioner of public works, several park board commissioners and members of the local Kiwanis Club.
The Ida Crown Natatorium was named in honor of the matriarch of a settler family. In the 1890s the Crown Family were residents of the Eckhart Park neighborhood, and several members of the family became local business leaders.
The twin Natatoria have served generations of swimming Chicagoans and continue to be places of recreation and exercise today. As public facilities operated by the Park District, Nesterenko and Werner designed the robust buildings to stand up to years of heavy use while requiring only limited maintenance. The eye catching arched roof canopies are both striking features and practical design solutions, providing a simple and efficient structural system and an open interior space unencumbered by columns. On the inside, the soaring ceiling overhead, transparent glass walls and sliding wall panels which open to the outside create a great space adaptable to year-round swimming.
The next time you head to either Pilsen or West Town, be sure to bring your swimming suit and stop by one of these fantastic natatoria for a dip.
Dimitri Nesterenko and Sommerschield, Harold, Barrel Shell Roof Used for Two Natatoria in Chicago, Journal of the American Concrete Institute (1962); 873.