Sewer overflow near the the Boat Club. (Photo courtesy Newtown Creek Alliance)

Sewer overflow near the the Boat Club. (Photo courtesy Newtown Creek Alliance)

Want to know when to avoid Newtown Creek like the plague? Just text 646-576-SHIT. (No, this is not a belated April Fools’ Day joke.)

It’s no secret that the creek is gross. And it can get even grosser when days of heavy rainfall, like last weekend’s, overwhelm the city’s wastewater treatment system and dump raw sewage directly into the creek.

It wouldn’t be as bad if, on days when the sewers overflow, Brooklynites postponed washing dishes, doing laundry or flushing the toilet (or as drought-stricken West Coasters put it: “if it’s yellow, let it mellow”).

So, in an effort to encourage residents to conserve water and increase awareness, the Newtown Creek Alliance has developed a Twitter alert system that automatically notifies followers that the sewers along Newtown Creek are overflowing.

The alert system, unveiled Sunday during an event at the North Brooklyn Boat Club, will also provide automatic updates every 24 hours for the next three years. “If you’re a boater or just interested in water quality in general, you have a better sense of when there’s sewage in the water,” Willis Elkins, Newtown Creek Alliance’s program director, said.

The alert debuted March 20, and sent out a bunch of updates over the weekend during the city’s first spring deluge.

Over the winter, the Newtown Creek Alliance installed 10 small weather stations — paid for with grant funding — on the rooftops of North Brooklyn and Queens public libraries within Newtown Creek’s watershed.

The Newtown Creek watershed

The Newtown Creek watershed

The stations gauge rainfall, wind speed, barometer, temperature and humidity. The real-time data transmits to a small, wireless base station inside the library, which sends the data to a live feed and to Weather Underground.

When it comes to treating the city’s waste and storm water — including water from flushing toilets, used laundry water, etc. — the Newtown Creek Wastewater Treatment Plant is one of the city’s largest. It can handle up to 700 million gallons of water each day, coming from almost all of north Brooklyn and Manhattan south of Union Square.  On any given day, approximately 1.3 billion gallons of wastewater is treated, according to the city.

But during heavy rain or snowstorms, the city’s treatment plants, including Newtown’s, aren’t able to handle the excess storm and wastewater. Lest it back up into toilets and sinks, untreated wastewater is discharged directly into waterways in what’s called a “combined sewer overflow” (CSO).

In a year, as many as 27 billion gallons of raw sewage is dumped in the city’s waterways, according to environmental organization Riverkeeper. The Newtown Creek Alliance estimates that about 14,000 million gallons of wastewater pollutes the creek each year.

The Twitter alert developed by the Creek Alliance is triggered when it rains one-tenth of an inch in an hour or four-tenths an inch in a day.

Leif Percifield during Sunday's presentation. (Photo: Amanda Waldroupe)

Leif Percifield during Sunday’s presentation. (Photo: Amanda Waldroupe)

A sewage overflow may not actually be caused after that much rain. But Leif Percifield and the Alliance landed at that threshold amount after correlating Department of Environmental Quality data showing exact times of known sewage overflows in the past with historical rainfall records and modeling how much wastewater the sewer system and treatment plants can handle.

“[It’s] a pretty good scientific guess of whether the sewer system is overflowing into the harbor,”  Percifield says.

Even if one weather station reports enough localized rainfall to potentially cause a sewage overflow into a small part of Newtown Creek, or one of its tributaries, the alert will go off. “If there’s one tributary that has an alert, it’s technically polluting the whole water body,” Percifield says.

The New York State Department Health advises that women under 50 and children under 15 years shouldn’t eat any fish or crabs caught from Newtown Creek, and that swimming and scuba diving in the creek can harm people’s health, and that the greatest exposure to health risks is from potentially swallowing the water.

In February, the department released a public health assessment that found that, based on various water samples taken in 2010, Newtown Creek contains 18 to 50 percent more bacteria and pathogens than recommended levels, including E. Coli, Shigella spp., Cryptosporidium and other bacteria originating in feces.

If the water is ingested, or boaters don’t wash their hands, the pathogens can contract a variety of gastrointestinal illnesses, Hepatitis A, and Giardia.

Want to get Newtown Creek Alliance’s Tweets about sewage overflows? Follow them at @NewtownCreek. You can also get texts sent your phone from 646-576-7448. And yes, those last four digits spell SHIT.