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By Stephen Press
Hometown Weekly Correspondent
You've seen them around town or perhaps at the end of your street. The "FIRE HYDRANT FLUSHING" signs are like the crocuses of the public works world, heralding the start of every spring with their appearance. Perhaps you've taken them for granted for years, knowing only that they exist, but not exactly what they mean. Or perhaps they've left you wondering what exactly your local DPW employees could be doing with fire hydrants at such ungodly hours. How does one flush a hydrant? Why is it important to do it in the first place?
As in any water system, the pipes are bound to fill with sediment as time goes on. By opening the hydrants - or flushing them, as it's called - the Public Works Department is able to keep the sediment from accumulating.
"The basic reason is to provide clean water," says Chris Seariac, Superintendent of Needham's Water, Sewer & Drain Division. "Like anything, deposits build up. You want the hydrant flowing at a certain number of feet per second; it scours the pipe to get rid of the mineral build-up."
And if the hydrants weren't flushed?
"Eventually, we'd have dirty water," he says, noting that Needham's Public Works Department is particularly vigilant in keeping the pipes clean. "Our water's nice and clear," he says with a hint of pride. "In other towns, the first five minutes of flushing might be dirty."
The nighttime scheduling? That's just to minimize the disruption to traffic and water customers. And it can be disruptive. Beyond the issue of water flowing in the streets, flushing a hydrant can cause temporary tap water discoloration.
"We're purposely stirring it up to clear it," says the Superintendent, "so that's another reason to wait until night." Though he's quick to note that the discoloration is not dangerous. "It's not unsafe," he adds, "but I'd prefer you didn't drink it. Turn on the cold water and run it until it's clear."
In short, those "FIRE HYDRANT FLUSHING" signs aren't simply your cue to begin spring cleaning. They're a valuable reminder that your Public Works Department is hard at work keeping your tap water flowing clearly and, most importantly, safely.
Seariac pauses a moment and smiles, thinking of the residents wondering why he and his colleagues are opening fire hydrants in the wee hours of the morning. "People think we're wasting water, but we're not."
The Needham Public Works Department will be flushing hydrants through April 27. A schedule can be found at www.needhamma.gov/hydrantflushing.
Stephen Press is a Correspondent at Hometown Weekly. He can be reached at [email protected].