The Avac is New York’s only pneumatic garbage-collection system. Designed in the late nineteen-sixties to service Roosevelt Island’s housing developments, the system runs under all the island’s high-rises. When people throw their garbage down the trash chutes, it piles up for several hours, until a trapdoor opens, sucking the waste into a big underground pipe. Then a complex system of air valves propels the garbage through the pipe at speeds of up to sixty miles per hour. When the trash resurfaces at the Avac center, a squat building at the northern tip of the island, it is dumped into two silo-shaped cyclones, where it is spun like cotton candy and then whooshed down chutes into huge containers.

Ron Marli is one of the people who control the Avac’s suction valves; on a normal day, he “pulls” between five and seven tons of garbage. Last year, though, construction began on two thousand new housing units on the southern end of Roosevelt Island, and now the whole Avac system has to be expanded. This is not a simple undertaking: the machine is Swedish, and it is maintained by a Swedish company called Envac, which has been called “the world’s largest pneumatic garbage systems maintenance company.” The nearest Envac repairman, Frederik Olsson, is stationed in Toronto.

Olsson has been spending a lot of time on Roosevelt Island lately, hanging around the Avac center while the expansion is in progress. “It is a strange way to visit America, but oh, well,” he said the other day, when he dropped by the center with Soren Hallberg, an En-vac technician from Stockholm. As they lounged with Ron Marli in the Avac center office, the building rumbled with the vaguely digestive thrum of after-lunch waste moving through the pipes.

According to Marli, a small man with a gravelly voice and a pale-yellow beard, the system was conceived at the time when the island, which had been the site of an insane asylum, was being rebuilt as an experiment in social housing. “The idea was no trucks,” he said. “No garbage on the streets.” In 1975, Roosevelt Island received the second pneumatic garbage system in the nation. “The other one is in Disney World,” Marli said. “And, if I ever lose my job here, I’ll go to that one.”

Olsson, a tall blond man in work boots and loose overalls, coughed politely. “Magic Kingdom can be problematic,” he said. “I visit it often. It usually breaks because so many sticky things run through it. This one usually breaks down because New Yorkers throw too many big things away.”

“The machine doesn’t break down that much,” Marli said. “But, you know, you get a rainy weekend and people clean out their closets. They throw away the weirdest stuff. Stereos, old computers, steel pipes.” The unwieldy objects sometimes clog the works. One time, a piece of rebar backed up the machine for several hours. Another time, it was a skillet. Envac workers have also recovered geometry textbooks, tape players, window frames, lumber, and old clothes. On a third-floor window ledge, there is an array of houseplants in industrial buckets, rescued from the trash.

“Swedes do make less garbage, I think,” Olsson said. “But the real problem is that Americans tend to run their machines too fast. They just dispose of anything and then, poof, want it sucked away. It really adds to the wear and tear on their system.”

Hallberg leaned forward. “They have whole towns in Sweden where the system runs wholly automatic,” he said.

“Perhaps you could use an Avac under Manhattan,” Olsson suggested. “Then you would get the trash bags off the streets. You could run it under the subway.”

“Yeah, but God knows what would show up in it then,” Marli said.