The water main break at Centre and South Negley avenues caused either low or no water pressure for residents of the central and eastern parts of Pittsburgh.
(Scroll down for full list of affected neighborhoods.)
"Will it mean that there will be additional inconveniences to people?
But it will also mean that we’re doing everything to make sure that your water is safe," Mayor Bill Peduto told Pittsburgh’s Action News 4.
The boil water advisory is a precaution taken in case bacteria got into the system while the water pressure was low.
"We are going to take every effort to err on the side of caution.
After what happened in Flint and in other areas, the worst thing you can have is a government that doesn’t over-react to these types of situations," Peduto said.
"So although there’s no risk to the public, the boil advisory will stay in effect until we’ve had two consecutive testings for bacteria.
The earliest the final test results will be available is tomorrow evening, Tuesday, December 19, 2017."
The minute starts when the water begins to bubble.

The Genesee County Drain Commissioner’s Office has issued a boil water advisory for the city of Swartz Creek, Clayton Township and Gaines Township.
Due to loss of water pressure, there may be bacterial contamination in the water system.
Because of the water main break, Swartz Creek Schools will be closed Dec. 19.
Bacteria are generally not harmful and are common throughout our environment.
The county drain commissioner’s office advises to not drink the water without boiling it for one minute first and then letting it cool down before using it.
Boiled or bottled water should be used for drinking, making ice, brushing teeth, washing dishes and food preparation.
The office is investigating the cause of the low water pressure.
The office said it expects to have the problem solved within one week and will inform the public when the advisory is lifted.
Copyright 2017 WNEM (Meredith Corporation).
All rights reserved.

Monday, Dec. 18, 2017 WARRENVILLE, S.C. (WRDW/WAGT) — A boil water advisory has been issued for some customers of Valley Public Service Authority.
Officials say customers residing on McCampbell Street, and on Augusta Road and Aiken Boulevard, between Rhoden Street and Cemetery Road in the Warrenville, South Carolina area, that experienced an interruption in their water service or low water pressure on Monday, Dec. 18, should vigorously boil their water for at least one full minute prior to drinking or cooking, until further notice.
They say there has been no confirmed contamination of the system.
But because of the interruption in service due to a water main break, the potential for contamination exists.
They also say any ice made from water which has not been boiled should not be used for drinking purposes.

PITTSBURGH – The Pittsburgh Water and Sewer Authority has issued a precautionary flush and boil water advisory for several sections of Pittsburgh.
Following a large water main break on Centre Avenue in East Liberty Sunday morning, the PWSA restored pressure following a period of low and no water pressure for customers in the central and eastern sections of Pittsburgh.
“Though our regulations require the precautionary flush and boil water advisory, disinfectant levels in our system have remained stable, and we have not detected the presence of any contaminants,” the PWSA said in a statement.
“Regulations require multiple follow-up water quality testing before the advisory can be lifted.
The earliest the test results will be available is the evening of December 19, 2017.”
Both hospitals remains operational and there is no impact on patient care.”
The PWSA also noted that there is currently a water buffalo located at Centre Avenue, where the main break occurred, and South Euclid Street for those without water.
A busy Pittsburgh street looked more like a river Sunday morning as water rushed down Centre Avenue following a water main break.
Huge water main break in East Liberty pic.twitter.com/ETv13m1Bbk — Lori Houy (@WPXI_Lori) December 17, 2017 The break impacted water service and pressure at UPMC Shadyside and Mercy hospitals, in addition to surrounding neighborhoods.
The water main break also forced businesses to close as residents flooded grocery stores looking for bottles of water.

A boil water advisory has been issued for the Warrenville, South Carolina area.
Customers of Valley Public Service Authority Water System residing on McCampbell St., on Augusta Rd.
and Aiken Blvd., between Rhoden St. and Cemetery Rd.
: If you experienced an interruption in your water service or low water pressure on Dec. 18, you will need to vigorously boil your water for at least one full minute prior to drinking or cooking, until further notice.
Also, any ice made from water which has not been boiled should not be used for drinking purposes.
Although there has been no confirmed contamination of the system, precautions should be taken because an interruption in service due to an unforeseen water main break has the potential for contamination.
The South Carolina Department of Health and Environmental Control (SCDHEC) is presently working with the water system to handle the problem.
If you should have any questions concerning this notice, you can contact the water system at (803) 593-2053.
Copyright 2017 WFXG.
All rights reserved.

The advisory is due to a water main break.
The advisory is in place for HWY-41 A, including: Fairview, Country Club Meadows, Hudson Meadows, HWY-120 in city limits, and HWY-814.
For the latest breaking news and stories from across the Tri-State, follow Eyewitness News on Facebook and Twitter.
(This story was originally published on Dec. 17, 2017)

A precautionary boil water advisory has been issued for parts of several Pittsburgh neighborhoods after a major water main break in Shadyside Sunday.
The water main break at Centre and South Negley Avenues caused low and no water pressure for residents of the central and eastern parts of Pittsburgh.
The Pittsburgh Water and Sewer Authority (PWSA) is issuing a precautionary boil water advisory to a limited area because a decrease in pressure can allow contaminants to enter the drinking water.
PWSA is conducting testing to confirm adequate disinfectant levels and ensure that the water is safe to drink.
A searchable map of the impacted areas is available here: PWSA Boil Water Area.
Any resident who experienced no water service today is also encouraged to follow these measures.
Customers within the impacted area should do the following before using water for drinking, making ice, washing dishes, brushing teeth, and food preparation until further notice: Residents who do not know if their property has lead water pipes or solder, it is recommended to first flush your lines by running water from your tap for at least one minute before boiling.
Wait for the water to cool before using it, or store it in the refrigerator in a clean container.
Residents should throw away ice made during the time the advisory was issued, as freezing does not kill bacteria.
A frequently asked questions document for boiling water can be found on the www.pgh2o.com homepage.

A major water main break Sunday in the East End may have contaminated drinking water in eight Pittsburgh neighborhoods — and residents should boil their water as a precaution, according to the Pittsburgh Water and Sewer Authority.
The 20-inch water main break was reported around 7 a.m. and was pinpointed to the intersection of Centre and South Negley avenues around 10:30 a.m., said Will Pickering, communications manager at PWSA.
The boil advisory affects approximately 7,000 homes and is expected to last at least until Tuesday evening, Mr. Pickering said.
“The major concern is that when the pressure drops there is an opportunity for bacteria to enter the void in the pipe, should there be a hole in the pipe,” Mr. Pickering said.
“When there is high pressure, there is no opportunity for pathogens to enter the pipe.” PWSA employees are testing the area’s water to ensure it is safe, Mr. Pickering said, and so far all of the tested water has been adequately disinfected.
The earliest that testing could conclude would be Tuesday evening, he said.
Crews began to repair the water main break Sunday and will continue Monday, he said.
Some areas of Centre Avenue have no water, he said, including two large apartment buildings and several commercial facilities.
PWSA has placed water tanks at the intersections of Centre and South Negley avenues, as well as at Centre and Euclid avenues, he said.
Shelly Bradbury: 412-263-1999, sbradbury@post-gazette.com or follow @ShellyBradbury.

PITTSBURGH (KDKA) — A precautionary boil water advisory has been issued to a few sections of Pittsburgh due to a water main break that happened Sunday morning.
The boil water advisory affects about 7,000 homes in the following areas: Bloomfield Central Lawrenceville East Liberty Friendship Garfield Highland Park Morningside Shadyside The advisory comes after a major water main break that happened at Centre Avenue and South Negley Avenue.
The Pittsburgh Water and Sewer Authority says they are issuing a precautionary boil water advisory because a decrease in water pressure can allow contaminants to enter the drinking water.
Tests are being conducted to verify the water is safe to drink.
Water should be boiled before drinking, making ice, washing dishes, brushing teeth or use in food preparation.
If you don’t know if you have lead water pipes or solder, you should run tap water for at least one minute before boiling it.
The PWSA says to follow these instructions: Boil tap water vigorously for at least one minute prior to using it for drinking or cooking (the minute starts when the water begins to bubble).
This includes water used for brushing teeth, making ice, washing raw foods, preparation of drinks, and water for pets.
Wait for the water to cool before using it, or store it in the refrigerator in a clean container.
The advisory is in effect until further notice.

One of them is GenX, a man-made compound that manufacturing facilities have discharged into North Carolina’s Cape Fear River for decades.
Mike Watters: 6 September of this year.
He had no inkling that his water might be contaminated until the company tested his well and told him it had an unsafe level of an unregulated chemical known as GenX.
And he’s not alone: residents of 115 homes within a few miles of the plant have been told their water is not safe to consume.
Hari Sreenivasan: Detlef Knappe, a professor of environmental engineering at North Carolina State, was part of the team who found GenX in downstream samples.
Hari Sreenivasan: The DEQ confronted the company in June, and Chemours agreed to stop discharging GenX into the Cape Fear River.
Hari Sreenivasan: The Cape Fear Public Utility Authority’s Sweeney treatment plant is about 80 miles downstream the Chemours plant.
Jim Flechtner, Executive Director, Cape Fear Public Water Utility Authority: It wasn’t necessarily designed to filter some of these compounds out because they’re not regulated at the national and state level.
Hari Sreenivasan: Meanwhile, residents downstream from the Chemours plant are grappling with the news that gen x and other fluorochemicals are in their drinking water.
Hari Sreenivasan: Two months ago there was another scare for downstream residents: a spill at the Chemours plant caused levels of GenX to spike to almost five times the state’s health goal of 140 parts per trillion.