Laura Bliss is CityLab’s West Coast bureau chief. She also writes MapLab, a biweekly newsletter about maps (subscribe here). Her work has appeared in The New York Times, The Atlantic, Sierra, GOOD, Los Angeles, and elsewhere, including in the book The Future of Transportation.
Desperate for snow-disposal solutions, Boston has asked the public for ideas. Scientists weigh in on the most responsible options.
With a record-shattering six feet of snow covering Boston in just four weeks—and more coming Thursday—the city is scrambling to find places to stash its plowed snow. Should they keep hauling it off to the Skywalker-esque "snow farms" dotting the city? Revisit the Colonial past with a giant snow dump into the harbor?
The city's desperate enough to have put out a call yesterday to academics, environmental leaders, and the general public for novel snow-disposal ideas.
After all, neither the snow farms (the city's current solution) nor the harbor (an idea that's being floated) are perfect options.
At the "farms"—vacant lots turned icy wonderlands—some snow stays frozen in piles up to 40 feet high, disappearing only with the spring melt. Other loads get fed into fearsome melting machines, which filter out the street-snow's nasty gunk (oil, gas, salt, and all manner of trash items) before spouting warm runoff into storm drains (and, eventually, Boston's harbor, rivers, and estuaries) at a rate of 400 tons per hour. The machines might be effective, but they're gas-guzzlers, and a drain on city resources.
How about dumping snow into the harbor? It's normally prohibited by state law, because of the environmental impacts of the snow's salt and contaminant content. (The practice was common until a massive cleanup of the infamously dirty harbor in the '90s led to tighter restrictions.) But Boston's public safety might soon override environmental concerns, as Mayor Martin J. Walsh told the press Monday, and the harbor might become a last-ditch receptacle.
“We’re not at a public-safety concern yet,” Walsh said, “but we will be if we keep getting snow like this.”
So what's a city to do?
A number of local environmental agencies and organizations have stepped forward in support of dumping into the harbor if other options get snowed under. So have some oceanographers.
...the Boston Harbor contains about 10 million tons of salt. As of February 10, the city had dumped about 60,000 tons of the stuff onto roads, or less than 1 percent of what’s in the water. So even if all the snow from the streets entered the water at once, it still wouldn't significantly impact the harbor's salinity.
So harbor dumping = no big deal, right? Not quite, according to Mi-Hyun Park, a professor of environmental engineering at a UMass Amherst who researches stormwater-runoff management. There's more to be concerned about than mere salinity levels.
"It's not going to be good, because you're going to directly increase pollution into the harbor," she says. "Snow can pick up pollution from the air in addition to the oil and deicing agents it can pick up from the road."
Park loosely analogized the harbor plan with sending untreated wastewater into the ocean—a practice that, when added up, can have catastrophic results.
Since there's much we don't know about the type and quantity of pollutants in Boston's street-snow, Park says it's probably best to keep using the snow farms, carbon-hungry as they are. Depending on location, snow-farm runoff is often treated before getting deposited into the water. Sometimes nearby soil and dirt can also act as a natural filter for all the gunk.
Yet as the Northeast gets pounded with more extreme snowfall, year after year, cities can't just maintain status quo. More research is needed to understand the environmental impacts of snow and snow-melt—and to figure out new ways of dealing with it. "There is a great need to work on this kind of research," says Park.
That way, maybe Boston won't have to scramble the next time it gets slammed.