With the full heat of the long summer just kicking in, this past February’s Winter Storm Jonas, which dumped a record 27.5 inches of snow in Central Park, can seem like a distant memory. Notwithstanding that December 2015 was the warmest on record, New York City will continue to be slammed by storms like Jonas and the blizzards of 2006 and 1996, as well as snowstorms that might be more mundane but nevertheless paralyzing to city streets in their own right. That is why residents of Lower Manhattan can look upon the New York City Department of Sanitation’s (DSNY) new Spring Street Salt Shed as a comfort and reassurance as the next inevitable winter looms on the distant horizon—and, given its unique, striking design, as an object of civic pride.
The salt shed is a towering, angular piece of public sculpture constructed of cast-in-place concrete and designed to evoke a crystal of salt (albeit on a gigantic scale). While concrete is something that many of us generally take little note of—utilitarian and ubiquitous; underfoot as sidewalks or train platforms, or else deployed serviceably in nondescript structures—not so in the case of the Spring Street Salt Shed. Its faceted planes enliven the reinforced concrete structure, the blue hue of which is the result of slag, intended to eventually weather to approximate the color of salt. The building’s solid, crystalline form acts as a counterpoint to the diaphanous, scrim-like façade of the Manhattan Districts 1/2/5 Garage across Spring Street to the north (no coincidence, since both structures were designed by Dattner Architects). The salt shed rises to nearly 70 feet at the intersection of Canal and West Streets, tapering at the bottom to allow more pedestrian space.
While the New York City Department of Design and Construction (NYCDDC) eschewed more workaday alternatives, it did not skimp on functionality or durability. The salt shed’s walls are six feet thick and lined with one-inch-thick steel plating on the lower eight feet of the interior; the steel serves to absorb whatever punishment might be inflicted by the constant stream of salt trucks going in and out during a winter storm event. More than 138,000 cubic yards of concrete were required to build the structure. The salt shed’s 5,000-ton salt capacity and the associated salt truck traffic obviously necessitated an appropriately massive foundation; in this case, a reinforced concrete slab that is over four feet thick in places, itself supported by 120 steel drilled caissons socketed into the bedrock more than 100 feet below street level. Moreover, not only is the salt shed’s concrete structure far more resistant to aggressive salt corrosion than, say, a galvanized steel Quonset shed, its striking design motif and heroic scale are also more suited to its high-end location on the interstice of SoHo and Tribeca.
The salt shed’s walls are higher on the side facing the Hudson River; this allows new batches of salt (delivered from as far away as Chile and Argentina) to be deposited on top of the pile at the taller end where it will slope down for easy access by salt-spreader trucks. Both delivery trucks and salt spreaders have easy egress through the 35-foot-high, 24-foot-wide doors. The steel plating lining the inside walls is replaceable, so that any damage done by trucks or by salt corrosion can be easily rectified.
The DSNY’s Spring Street Salt Shed and the Manhattan Districts 1/2/5 Garage collectively received a Leadership in Energy and Environmental Design (LEED) Gold Certification this year from the US Green Building Council. Sustainable design features include the salt shed’s capacity to hold 5,000 tons of rock salt, thereby cutting down the need for salt spreaders to travel longer distances to reload; and the garage’s green roof with 25 drought-resistant plant species and the use of harvested rainwater and steam water as graywater and for truck washing. Additionally, snow removal vehicles for each of the three Community Districts served by these structures will be housed in the garage, their next-door proximity to the salt shed further minimizing their vehicular emissions footprint as well as allowing for rapid deployment during the critical hours of a winter storm.
HAKS provided special inspection and monitoring services to the NYCDDC for the $20 million salt shed, including concrete field, rebar, pile, soils, structural steel, structural bolting, flood zone, mechanical, and energy code compliance inspections. We monitored, advised, directed, and reported on field installations prior to and/or as they occurred.