Some section of the city's 7,500 miles of sewer lines gets blocked virtually every day, and discarded cooking oil is the reason 60% of the time. But in parts of Queens, that grease is the culprit in nearly 80% of all sewer backups, a problem that is especially acute near Kennedy Airport.
Experts say one reason Queens' sewers get blocked so often is that a lot of food is prepared in the city's most diverse borough, where residents, who hail from 120 different countries, might not be familiar with the best grease-handling practices.
In an effort to educate the public on the ills of grease dumping, last year the city enlisted interns from the Summer Youth Employment Program to knock on neighborhood doors as part of its Cease the Grease campaign. The teenagers visited more than 50,000 Queens households and 1,000 restaurants to remind people that used cooking oil and fat should be sealed in nonrecyclable containers and thrown out with the rest of the trash, not poured down the sink.
But grease has been blocking big city sewers practically since the pipes were laid. In 1859, a Brooklyn sewer commissioner observed that "melted grease is very objectionable." Two years ago in London, an 11-ton mound of congealed fat was extracted from a sewer, requiring more than $600,000 in repairs.
Grease causes sewer backups all over the city, but they most commonly occur in certain Queens neighborhoods including South Jamaica and St. Albans, where more than 4,800 complaints were made in the past five years, an average of nearly three per day. The city received almost 15,000 reports of greasy sewer clogs during that time, according to 311 call logs—numbers that suggest one-third of the most mucked-up city sewers are located in neighborhoods that house less than 5% of New York's 8.5 million residents.
Although some of those sewer problems can be linked to the vast amounts of cooking oil used in preparing dishes such as deviled fish, a deep-fried delicacy on the menu at many Sri Lankan restaurants in southeastern Queens, experts say the chronic backups mostly reflect the area's history and geography.
Sewer pipes in southeastern Queens tend to be 10 inches in diameter, Adamski said—less than half the typical size in other boroughs—because they were installed decades ago, when the area was relatively undeveloped. Southeastern Queens is also a flood basin, so its streets and basements are vulnerable to sewer backups after even modest rainfalls. The problem's origins go back to the 1940s, when a natural drainage area was paved over to build runways for JFK. Moreover, the area's groundwater table has steadily risen during the past decade or so. Climate change is a factor, and so is the fact that the city no longer pumps the ground wells that once provided the area's drinking water.