Detroit boil-water advisory lifted.
The second round of test results came back clear, finding "nothing wrong with the water," according to a statement from the Great Lakes Water Authority.
People in affected areas this week had to boil their water before drinking it or using it to cook, in case it was contaminated with bacteria.
"While the boil water advisory has been lifted, DWSD recommends that if water has not been used for six hours or more, water should run from the tap until it is cold and continue to run for an additional two minutes for fresh water," according to a news release from Detroit Water and Sewerage Department.
Related: The department reported that the possibility of bacterial contamination occurred when an equipment malfunction caused a temporary drop in pressure from one pump at the system’s big water-treatment plant on East Jefferson, at the former Water Works Park (long closed to the public).
The facility is operated by the Great Lakes Water Authority.
"Bacteria are generally not harmful and are common throughout the environment," a previous news release said.
In today’s news release, the department said that the Michigan Department of Environmental Quality standard for issuing a boil-water advisory occurs when water presser falls below 20 pounds per square inch.
Detroit’s pressure never fell that far, but the advisory was issued as a precaution, according to the release.
Contact Robert Allen on Twitter @rallenMI or rallen@freepress.com.

Boil Water Advisory To Keep Detroit, Hamtramck Schools Closed Friday.
DETROIT (WWJ/AP) – More than two dozen public schools in Detroit will remain closed Friday due to a boil water advisory covering parts of the city and the enclaves of Hamtramck and Highland Park.
Schools in Hamtramck will also be closed Friday for a third-straight day.
The Detroit Public Schools Community District says that after the advisory is lifted water lines in the 29 schools will be flushed with running water prior to Monday morning’s start of classes.
The Detroit schools were closed Thursday as a precaution following the advisory, which was announced earlier this week.
An equipment malfunction at a Great Lakes Water Authority treatment facility on Tuesday caused low water pressure.
The problem was addressed, but the advisory was issued due to concerns that bacteria could have gotten into the system.
Customers will be advised when the boil water advisory has been lifted, which is expected by noon Friday.
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The Associated Press contributed to this report.

DETROIT – Parts of Detroit, Hamtramck and Highland Park are still under a boil water advisory Thursday after a temporary drop in water pressure on Tuesday night might have caused a potential bacterial contamination in the water system.
Bring all water to a boil, let it boil for one minute and let it cool before using it, or use bottled water.
Crews from the Great Lakes Water Authority and the Detroit Water and Sewerage Department are working to get pressure restored, and water staff flushed and took bacteriological samples from around the system.
If residents or businesses have no water service in the area affected by the advisory, they are asked to call the DWSD emergency line at 313-267-7401.
Detroit schools closed Dozens of Detroit public schools closed Thursday because parents were concerned about their children drinking the city’s water.
"As a further precautionary measure, the district has made the decision to close the 26 schools in the affected area and to err on the side of caution," officials said in a statement.
Click here to view the list of Detroit public schools closed by the boil water advisory.
But officials said they received a lot of calls from parents who are concerned and upset that their children were drinking the water on Wednesday and didn’t realize that they were under a boil water advisory.
DPSCD was given a list of schools affected by the advisory on Wednesday morning, but it wasn’t complete.
My concern is our staff and our students were there all day consuming this water," parent Lamethia Champion said.

DETROIT – Parts of Detroit, Hamtramck and Highland Park are still under a boil water advisory Thursday after a temporary drop in water pressure on Tuesday night might have caused a potential bacterial contamination in the water system.
Bring all water to a boil, let it boil for one minute and let it cool before using it, or use bottled water.
Crews from the Great Lakes Water Authority and the Detroit Water and Sewerage Department are working to get pressure restored, and water staff flushed and took bacteriological samples from around the system.
If residents or businesses have no water service in the area affected by the advisory, they are asked to call the DWSD emergency line at 313-267-7401.
Detroit schools closed Dozens of Detroit public schools closed Thursday because parents were concerned about their children drinking the city’s water.
"As a further precautionary measure, the district has made the decision to close the 26 schools in the affected area and to err on the side of caution," officials said in a statement.
Click here to view the list of Detroit public schools closed by the boil water advisory.
But officials said they received a lot of calls from parents who are concerned and upset that their children were drinking the water on Wednesday and didn’t realize that they were under a boil water advisory.
DPSCD was given a list of schools affected by the advisory on Wednesday morning, but it wasn’t complete.
My concern is our staff and our students were there all day consuming this water," parent Lamethia Champion said.

Detroit Boil Water Advisory: First Tests Come Back Clear.
DETROIT (WWJ) – Officials say the first round of tests came back clear while a big chunk of the city of Detroit remains under a boil water advisory.
The Michigan Department of Environmental Quality said in a media release, Thursday afternoon, that while the results of the tests by the Great Lakes Water Authority (GLWA) “are a sign that there is nothing wrong with the water,” the advisory will remain in effect at least until noon on Friday, to be safe.
Upon a second clear result, the GLWA will recommend that the boil water advisory be lifted.
This includes downtown Detroit and the campus of Wayne State University, along with all of Highland Park and Hamtramck.
Meantime, dozens of Detroit schools were closed as a result, and numerous local business have been affected.
Grace Forrest, a barista at Roasting Plant in Campus Martius, said they’re using bottled water to wash the dishes and aren’t able to serve iced coffee.
Boiled or bottled water should be used for drinking, making ice, brushing teeth, washing dishes, and food preparation until further notice.
Boiling kills bacteria and other organisms in the water.
Any residents or businesses without water service in the defined area is urged to contact the Detroit Water and Sewerage Department’s emergency line at 313-267-7401.

Boil Water Advisory Issued for Northeast Chatham County.
Chatham County Water Utilities has issued a boil water advisory for the northeast portion of the county.
The advisory was caused by a water leak causing a drop in water system pressure.
Officials said the leak was repaired on Thursday morning but did not say how long the leak lasted.
“We are issuing the boil water notice as a precaution due to the pressure drop in the system,” assistant county manager Dan LaMontagne said in a release.
“We do not expect this to last more than one day.” County officials had started calling the affected residences and businesses to alert them of the notice on Thursday.
The impacted communities are Mann’s Chapel Road, Hamlet’s Chapel Road, Mt.
Gilead Church Road, Bynum Bridge Road and Highway 15/501 south of Jack Bennett Road.
Several other communities were affected including Hudson Hills, The Hamptons, Bynum, Briar Chapel, Fearrington Village, Galloway Ridge, Hamlet Grove, Prestonwood, Horizon and Moneterrane.
Anyone with questions is asked to contact Water Utilities at (919) 542-8270.

Boil Water Advisory Issued for Northeast Chatham County.
Chatham County Water Utilities has issued a boil water advisory for the northeast portion of the county.
The advisory was caused by a water leak causing a drop in water system pressure.
Officials said the leak was repaired on Thursday morning but did not say how long the leak lasted.
“We are issuing the boil water notice as a precaution due to the pressure drop in the system,” assistant county manager Dan LaMontagne said in a release.
“We do not expect this to last more than one day.” County officials had started calling the affected residences and businesses to alert them of the notice on Thursday.
The impacted communities are Mann’s Chapel Road, Hamlet’s Chapel Road, Mt.
Gilead Church Road, Bynum Bridge Road and Highway 15/501 south of Jack Bennett Road.
Several other communities were affected including Hudson Hills, The Hamptons, Bynum, Briar Chapel, Fearrington Village, Galloway Ridge, Hamlet Grove, Prestonwood, Horizon and Moneterrane.
Anyone with questions is asked to contact Water Utilities at (919) 542-8270.

Detroit boil water advisory: What you need to know.
Here’s what you need to know about a boil water advisory.
What is a boil water advisory?
It’s a public health advisory given by government officials when a city or community’s water system could be contaminated by bacteria.
Until the advisory is lifted, residents are advised to boil water before drinking it or using it to cook to ensure there is no bacteria before consumption.
Read more: Who is affected by Detroit’s boil water advisory?
According to the Detroit Water & Sewerage Department (DWSD), the possibility of bacterial contamination occurred when there was a temporary drop in pressure from one pump at the system’s big water-treatment plant on East Jefferson, at the former Water Works Park (long closed to the public).
What do I need to do during a boil water advisory?
What if I don’t know about the boil water advisory and drink and/or use the water anyway?
The water pressure is back up in every area of the city, and as soon as we get the green light from the DEQ we will revoke the boil water alert."

More than 2 dozen Detroit public schools closed due to boil water advisory.
DETROIT – More than two dozen Detroit schools have been closed due to a boil water advisory affecting parts of Detroit, Hamtramck and Highland Park, officials announced Wednesday night.
But officials said they received a lot of calls from parents who are concerned and upset that their children were drinking the water Wednesday and didn’t realize they were under a boil water advisory.
The decision to close the schools was made out of "an abundance of caution."
When DPSCD was given a list of schools affected by the advisory Wednesday morning, it wasn’t complete.
"I’m really not concerned at whose issue it is, my concern is our staff and our students were there all day consuming this water," parent Lamethia Champion said.
"How are you going to get all of these supplies delivered to 25 schools by the start of school tomorrow when you have a problem getting regular supplies delivered to schools on a regular basis?"
The school district heard parents’ concerns and decided to close 26 schools.
Check here Officials said a temporary drop in water pressure could have caused a potential bacterial contamination in the water system.
For more on what you should do during a boil water advisory, click here.

Equipment failure causes widespread boil water advisory in Detroit.
An equipment malfunction at a Great Lakes Water Authority treatment facility has caused a widespread boil water advisory in Detroit.
The advisory covers the area south of McNichols Road to the Detroit Riverfront and Linwood east to Conner Street, which includes the cities of Highland Park and Hamtramck.
For a map of the affected areas, refer to the image at the top of the page.
The malfunction at the treatment plant is said to have resulted in low water pressure, which enhances the risk of bacteria.
In a news release, Detroit officials urged those in the affected areas to not drink or use water without boiling it first.
"Bring all water to a boil, let it boil for one minute, and let it cool before using, or use bottled water," the release reads.
"This boil water notice shall remain in effect for the defined area until results from the sampling verify the water is safe to drink."
Detroit public schools issued a statement on the advisory, in which it says water in its schools will not be consumed in the next 48-hours for drinking or cooking unless boiled first.
"Operations-Facilities will shut off water at the drinking fountains at these buildings."