Everything you need to know about the grand white dome that’s about to reappear at Carter Playground on Columbus Avenue.
The bubble — the enormous UFO-like presence upon Carter Playground that signals the onset of winter — is about to be reinflated.
Which begs the question: Where has it been hibernating during the warm uncovered days of summer?
The answer: An Olympia Moving and Storage warehouse in Watertown, Massachusetts.
“It’s a good, climate-controlled, dry space that’s within reasonable proximity,” says Craig Lee, Northeastern University’s director of athletic facilities and event services.
Suburban Watertown happens to be less than 10 miles from the Boston campus. That distance matters.
“You’re talking about a large volume of material, a large weight of material,” Lee says. “So the Olympia solution has worked out really well for us.”
The bubble’s return will allow people in the Boston and Northeastern communities to participate in sports and other activities without submitting to the typical snow, rain, wind and other realities of New England winters.
The tentative plan is to reinstall the 72-foot-high bubble at the end of this week, with the main parts arriving Friday and inflation of the dome on Saturday. Workers must wait for a calm day with little rain.
“Once the bubble fabric is laid out, if we get any meaningful precipitation, that can be problematic for our inflation because any added weight is troublesome,” Lee says of the thick white Tedlar fabric. “And then we’re looking for winds below 10 mph and no gusts, and we need that for a good four-hour period.”
The perimeter, doors and seams of the bubble are not 100% airtight. However, once the bubble is installed the mechanical system is designed to account for any pressure loss.
The bubble includes eight sections of synthetic fabric, each thickened to a weight of 8,000 pounds. It is secured with more than 10,000 nuts and bolts, anchored by 30 steel cables — each one up to 400 feet long — and weighs 3,000 pounds.
Most of the assembly work and inflation is done by a firm visiting from New York. It begins with two days of work to prepare Carter Playground.
“We have to take down safety netting, remove substantially high safety netting poles and remove all the fencing around the perimeter of the field,” Lee says. “And then we have a crew that removes the turf panels to expose the grade beam, which is what the bubble attaches to to secure it to the ground.”
Rousing the dismantled bubble from its suburban slumber and transporting it back to Northeastern is no easy task. Compacted and stored away in the warehouse, the bubble takes up the space of several school buses, Lee says.
“Think of all of the components to put the bubble together,” he says. “You’ve got the fabric, the massive cables that anchor the bubble, the vehicle airlock, which is a double garage door that allows us to maintain pressure in the bubble while we bring in larger equipment and the pedestrian airlock, which is where all the daily users enter.”
All of these pieces will be carried by more than one dozen trucks to Columbus Avenue.
The costs of maintaining the bubble are part of Northeastern’s $108 million commitment to the 2018 renovation of Carter Playground, including $82 million for maintenance over a span of 30 years. The upgrade increased the park’s size by 25% by incorporating its Camden parking lot into the renovation.
The renewed park features two football and soccer fields that can also be used for a number of sports, as well as five tennis courts, open recreational space, and an area with equipment for children with disabilities that was dedicated to Victoria McGrath, who was injured in the 2013 marathon bombing and then died in a tragic accident overseas in 2016.