July 23, 2009

On the Surface

     What’s under foot in a playground might seem a lot less important than what’s in it. But what covers the ground of a play space can be as integral a part of the design as what kids climb, swing, slide, and spin on.

      Prior to their reconstruction, the play areas of both West 100th Street and Ancient playgrounds were surfaced entirely in sand—the answer to safety concerns at a time when playgrounds were typically paved in asphalt. Sand is also great to play with, particularly for younger children. And it’s good for the Park because—unlike playgrounds paved in asphalt—sand allows storm water to drain directly into the soil beneath, and its natural tone integrates nicely with the surrounding landscape. But sand poses a problem in that it’s not a wheelchair accessible surface. And as a safety surface, it’s only effective when maintained at a proper depth. In an urban playground, keeping sand at the required depth and maintaining vast amounts to the desired standard of cleanliness is an extremely time-intensive process that depletes much-needed resources better spent on other aspects of playground maintenance.

     While both of these reconstructions incorporate sand as an integral component of the design, it’s been used in places and ways that provide the greatest play value—and in combination with other types of surfacing to provide a more enjoyable, accessible, and safe play experience.

     Both playgrounds have sandboxes geared towards preschool-age children. At West 100th Street, the sandbox includes a user-operated water spout to provide for imaginative play with water and sand. The circular sandbox at Ancient Playground is integral to the ancient-city theme of the design; it terminates a “processional axis” leading into the playground from the entrance, and contains a tot-slide in the form of an obelisk. And at the heart of the West 100th Street Playground, is a “lake of sand” traversed by its signature bridge.

     Both playgrounds also contain an innovative safety surface  used here for the first time in Central Park: a durable outdoor carpet with layers of resilient material beneath. Developed and in use for two decades in the United Kingdom, this type of surfacing  is increasingly finding its way in the United States—particularly in the southwest, as a heat-resistant alternative to rubber safety surfacing. The carpet was specified in a neutral tone that resembles the natural appearance of sand. It has the benefit of being a free-draining surface, like sand, allowing storm water to drain into the landscape, but unlike sand, it is a wheelchair accessible surface.

     In Ancient Playground, a type of rubber safety surfacing composed of multi-colored granules was also used, and mixed in neutral tones consistent in character with the ancient-city theme.  With this material, it’s possible to create an undulating surface, an idea that was incorporated into the design of the playground, transforming the ground itself into an exciting play feature.