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Accessibility is crucial for children who use wheelchairs or other mobility devices to enjoy playgrounds, and a big part of that relies on surfacing.  Ground surfaces along accessible routes and maneuvering spaces must comply with the American Society for Testing and Materials (ASTM) F 1951- 99 standard. The standard measures the work an individual must do to propel a wheelchair across a surface; the force must be less than that required to push a wheelchair up a ramp with a slope of 1:14.  Surfaces such as engineered wood fiber, rubber surface tiles, and poured-in-place surfacing fall within this guideline, but sand does not.

Still, the properties of sand make it a great medium for play. Children can manipulate sand to construct sand castles, race tracks, animals, and imaginative worlds. And because it is a loose, porous material, sand responds in fascinating ways to water: gaining weight, becoming sticky, shrinking in volume, and dripping into improbable stalactites. Most of all, sand is often found in areas where children come together to learn lessons in sharing and cooperation, like when it is okay to use a shovel and when it is time to let someone else have a turn.

Sand tables 
Suffice to say, it would be a great loss to playgrounds to eliminate sand from all areas of a playground because it does not qualify as an accessible route under the ASTM standard. The U.S. Access Board acknowledges as much in a guide intended to help designers and operators meet accessibility guidelines. Included in the guide is a brief description of play tables, which are surfaces, boards, slabs, or contours designed for sand and water play, and gathering activities. Play tables can be easily integrated in play structures at a ground or elevated level to give wheelchair users the opportunity to play in the sand and manipulate it into a variety of forms.


When integrating sand tables and other accessible equipment in playgrounds, several design considerations are worth noting. First, a minimum clear floor space of 30” by 40” must be provided to allow unobstructed room to accommodate a single stationary wheelchair and its occupant. Next, for ground level and elevated play components accessible by ramps, maneuvering space for a wheelchair or mobility device to make a 180-degree turn is required. Finally, when located on an accessible route, wheelchair knee-clearance must be a minimum of 24 inches high, 30 inches wide, and 17 inches deep.

Reach-adapted sand table


One simple, inviting design is found at the Ruth and Arthur Smadbeck-Heckscher East Playground in Central Park. The park, as shown in the feature image at the top of this blog, was entirely reconstructed in 2014 as part of Plan for Play, the Central Park Conservancy’s comprehensive plan to enhance each of Central Park’s 21 playgrounds. A sand table that sits atop a corrugated metal base allows for near complete wheelchair accessibility. Nearby, one of the ground-level sandboxes has a wooden lip with parallel bars mounted at a low height to allow children with partial mobility to transfer directly to the sandbox for seated play. The rustic wood planks skirting the structure’s edge integrate well against the lush vegetation and make a nice seat for children or caregivers.


Sand table at Ruth and Arthur Smadbeck-Heckscher East Playground


Another thoughtful approach, as seen here, is a half-moon shaped sandbox and mounted sand table adjoining a hardscape of pavers. Because of its extended surface, the sand table is well within reach range of a seated wheelchair user (the U.S. Access Board recommends 18-40 inches for 5 to 8-year-olds). By being placed on the perimeter of the hardscape it does not interfere with play on the larger surface.

Accessible layouts
Designing ground-level accessible routes between play components can be a challenge in larger, more elaborate designs. The U.S. Access Board’s requirements stipulate a 60-inch minimum clear width and 1:16 maximum slope. The clever layout of the Kemp playground in Cambridge Common by landscape architect Robert Steck meets these guidelines, while optimizing access to a large selection of interactive sand and water equipment. The central location of the sand pit makes it fully accessible via a circular path, which extends to a small deck in the center of the layout. Goric’s Water Play System E, a staircase-like network of water channels and basins, provides easy access for children with mobility limitations, and the Conveyor Belt, Winder Pump, and Sand Silo are integrated into the design in a way that allows children to sift, shape, and convey sand and water.

Kemp playground in Boston’s Cambridge Common

Of course, depending on the city and region, creating opportunities for inclusive sand and water play comes with significant operational barriers. H Nyunny Kim of Michael Van Valkenburgh Associates, whom we spoke with this past summer, says that sand, as an element in new playground designs, is prohibited by some municipal parks departments, including Chicago’s. The resource costs of maintaining areas where diffuse materials can scatter may be a tough line item for budget-strapped municipal departments to subsume. And because sand is not considered an accessible surface, integrating it into playground designs that all can enjoy requires creativity and finesse. But let’s not let these challenges stand in the way of fresh thinking and experimentation. For us, the benefits of inclusive playgrounds with accessible, stimulating sand equipment make them well worth pursuing.