LATEST: Oconomowoc High School reopens Monday after carbon monoxide leak

LATEST: Oconomowoc High School reopens Monday after carbon monoxide leak

Updated: 8:13 a.m. March 26, 2018

OCONOMOWOC, Wis. (CBS 58) -- Oconomowoc High School students are back in class after their building gets the all-clear from fire officials. 

Students arrived at the building, as usual, Monday morning after a carbon monoxide problem shut down the school on Thursday. 

More than 150 people went to the hospital feeling ill with five of those people testing positive for high levels of carbon monoxide. The school district, fire department, and other investigators have been monitoring CO levels since Thursday and say they are down to a safe level now, but they still don't know where the carbon monoxide leak was or what caused it. 

Administrators say they are now reviewing their evacuation procedures and have determined they need to hold an active shooter training next month. 

They are also establishing a new student safety commission that will meet on Wednesday. It will focus on future training and how to educate the school community on safe emergency responses. 


Updated: 3:28 p.m. March 25, 2018

OCONOMOWOC, Wis. (CBS 58) -- In a statement on Sunday, Oconomowoc Schools say the High School and Oconomowoc Arts Center will reopen for normal school and activities on Monday, March 26.

The environmental company that has been monitoring air quality since the Thursday incident says they have not received any carbon monoxide or other dangerous levels above 1 parts per million (ppm) since a reading of 5 ppm Friday morning. The safety standard is below 9 ppm. 

The agency has been testing different pieces of equipment such as the boiler and hot water heater and have not seen any rise in CO levels since Friday. 

Any students who couldn't claim left items on Saturday can do so Monday morning from 7:05 a.m. to 7:15 a.m. Even with the cancellation of classes Thursday and Friday the school year will still end on June 7.

The five people who tested positive for carbon monoxide poisoning had blood levels which ranged from 2.3 ppm to 3.1 ppm. Clinical poisoning symptoms are not felt until 10 ppm. 

The testing agency issued a statement that said, "After 30 years of testing air quality in schools and buildings of many types and sizes, we can say that the levels documented here are typical of normal school or similar building operations."


Updated: 1:25 p.m. March 24, 2018

OCONOMOWOC, Wis. (CBS 58) -- In a tweet Saturday, officials with Oconomowoc High School say the school will be open from 3-6 p.m. March 24 for staff and students to retrieve their belongings. 

The school was evacuated Thursday for an "air quality issue" when students were sickened. On Friday, students and staff had been told they would be let back into the building to get their things but elevated carbon monoxide levels were later detected and they were not allowed in. 

The school says students and their families will be given detailed instructions so they can reclaim their items. 


Updated: 3:38 p.m. March 23, 2018

OCONOMOWOC, Wis. (CBS 58) -- Students at Oconomowoc High School are annoyed after they were told they would be allowed back into the school to retrieve belongings they had to leave behind after the evacuation on Thursday.

With no high readings registered Friday morning school officials thought they would be allowed to let students and staff back in for a short time around 3 p.m. Friday afternoon, but after slightly elevated levels of carbon monoxide registered in the Arts Center they have cancelled that. 

Both the high school and arts center will be closed through Sunday.

"I have my car keys in [the school], I have meds in there obviously that are not threatening that I need, but I'm having to use my mom's car and that's a struggle for her with work and everything else to do," said junior Lauren Seelow.

A concert scheduled for Friday night in the Arts Center has also been cancelled. Anyone who bought tickets will be refunded and more information will be available Monday.


Updated: 2:51 p.m. March 23, 2018

OCONOMOWOC, Wis. (CBS 58) -- After a Friday afternoon briefing, Oconomowoc Schools have learned that equipment inside the Oconomowoc Arts Center showed slightly raised levels of carbon monoxide.

The levels are below the standard of safety, but officials need to determine the source of the elevated readings before allowing anyone in the building. 

All practices and events at Oconomowoc High School and the Oconomowoc Arts Center have been cancelled for Friday and the weekend. 

Officials will work through the weekend to make sure the school is safe.


Updated: 10:58 a.m. March 23, 2018

OCONOMOWOC, Wis. (CBS 58) -- In a release late Friday morning, Oconomowoc Schools say that monitoring equipment placed in Oconomowoc High School Thursday night did not detect any carbon monoxide or other volatile organic compounds. More test equipment was installed Friday morning to test for thousands of other potential chemicals.

The building's heating and ventilation systems are also being checked.

Western Lakes Fire Department says 176 total students and staff were treated for symptoms. Of those, 64 were taken by ambulance to Oconomowoc Memorial and Aurora Hospitals. 40 additional patients walked in to Emergency Departments to be treated. 72 patients were treated at either Oconomowoc High School or Silver Lake Intermediate School, but not taken to the hospital.

As previously reported, five people that were taken to the hospital tested positive for carbon monoxide poisoning.

As of Friday morning, anyone treated at a hospital was released.


Updated: 6:13 p.m. March 22, 2018

OCONOMOWOC, Wis. (CBS 58) -- The Western Lakes Fire Chief confirms 5 people were treated for carbon monoxide poisoning following Oconomowoc High School Evacuation.

A total of 104 people were seen at both emergency rooms.

The Western Lakes Fire Chief says they've now narrowed down the carbon monoxide source to Oconomowoc High School.

The school and the fire department will continue to monitor for CO through the weekend. 

Stay with CBS 58 News as this story continues to develop.


Updated: 3:35 p.m. March 22, 2018

OCONOMOWOC, Wis. (CBS 58) -- Students rehearsing for the middle school concert spoke to CBS 58. Meghan Coates said that all of a sudden she started seeing black and then fainted, "Scared, like really scared because it could be lingering somewhere else."

Coates mother Jen said, "I'm relieved that she's doing well. Her tests all came back great, so a little scary to get that text in the morning and the phone call in the morning."

Alex Melgares said, "I was standing in rehearsal and about four girls down from me this girl just passed out of nowhere."

Like dozens of the students and staff taken to the hospital, Coates has been released with clear tests.Like dozens of the students and staff taken to the hospital, Coates has been released with clear tests.

School on Friday has been canceled at Oconomowoc High School for Friday. School will go on as scheduled for Silver Lake.


Updated: 12:30 p.m. March 22, 2018

OCONOMOWOC, Wis. (CBS 58) -- In a press conference, the Superintendent of Oconomowoc Schools said that a medical alert was called when students from the Silver Lake Intermediate School choir started feeling lightheaded and nauseous at the Oconomowoc Arts Center Thursday morning. 

Oconomowoc Police recommended the building be evacuated and classes canceled for the rest of the day. Students were dismissed in waves with those driving themselves leaving first, walkers next, those bused third and anyone being picked up by a parent was sent to St. Jerome's Church.

Western Lakes Fire Chief Brad Bowen said they were called to the scene at 9:22 a.m. The initial call was for five patients but that escalated to ten within minutes of being on scene. 

In total 73 patients were treated at local hospitals with 41 at Oconomowoc Memorial and 32 at Aurora. Twenty ambulances responded to both schools taking 35 patients to the hospital, the others drove themselves or were taken by parents. 911 was called for two patients who had already returned to their homes before feeling ill.

No serious injuries were reported.

Emergency officials say they had initial low carbon monoxide readings on patients but checked the school and no source of carbon monoxide was found. Officials are searching the school for a source of the sickness and are also looking at the school bus that transported the students from Silver Lake to Oconomowoc High School. The exact cause of the mass illness is unknown.

All after-school activities at Oconomowoc High School have been canceled including the choir concert that students were rehearsing for. School officials are still determining whether or not to cancel school for Friday. Silver Lake Intermediate is still in session.


Updated: 12:05 p.m. March 22, 2018

OCONOMOWOC, Wis. (CBS 58) -- A CBS 58 crew at Oconomowoc Memorial Hospital report seeing six students leaving the hospital. It is unknown if all of those students were treated for the "air quality" issue at Oconomowoc High School.

School officials held a press conference Thursday afternoon following the incident. 


Updated: 11:43 a.m. March 22, 2018

OCONOMOWOC, Wis. (CBS 58) -- Some students from the Silver Lake Choir were treated for feeling ill at a rehearsal at the Oconomowoc High School Arts Center. Other choir students said they did not start to feel sick until after they got back to Silver Lake Intermediate School. Emergency personnel are responding to Silver Lake to evaluate those students.

If a parent has a child in the Silver Lake choir they can call the front office at 262-560-4300 to check on the status of their child.

CBS 58 crews on scene report seeing at least a half dozen ambulances at Oconomowoc High School. Students can be picked up by their parents at St. Jerome's Church.

Multiple students tell CBS 58 they were told it was carbon monoxide-related. Students report seeing multiple victims being treated by emergency personnel. 

Some students were transferred to Oconomowoc Memorial Hospital, but the exact number of students currently being treated is unknown.


Posted: 10:02 a.m. March 22, 2018

OCONOMOWOC, Wis. (CBS 58) -- Oconomowoc High School and Oconomowoc Arts Center have been evacuated due to a possible "air quality" issue. 

In a statement posted by the high school on their Facebook page, Silver Lake Intermediate students were rehearsing for a choir concert when they became lightheaded and complained of feeling ill. Emergency personnel were called to the scene and Silver Lake and Oconomowoc High School students were evacuated from the buildings. 

Below is the statement posted by the High School on their Facebook page


There has been an unexpected situation at OHS and the OAC this morning. This is not a situation of school violence, it is a possible air quality issue. Silver Lake Intermediate students rehearsing for a Choir Concert became lightheaded and complained of feeling suddenly ill. Emergency personnel were called to the scene, and Silver Lake and Oconomowoc High School students were evacuated from the buildings.

We have determined that students and staff should not re-enter the building until we can confirm it is safe. OHS students are being dismissed immediately, for the remainder of the day. Oconomowoc Transport is enroute to pick up students to bring them home.

Students with possessions inside the building will not be allowed to re-enter for those items.

We will communicate further details as soon as possible. Emergency personnel are inside the building now.

For parents arriving to pick up their OHS students this morning:

OHS students being picked up by parents will meet their parents in the St. Jerome’s Church parking lot.  OHS staff will be on-site to help check students out and ensure their safety.

St. Jerome’s Church is located at 995 Silver Lake Street, Oconomowoc.

A student witness told CBS 58 he was sitting in class when students were evacuated for a possible carbon monoxide situation. The student said as they were evacuated he saw several students being helped by emergency responders and some kids were fainting.

This is a developing story. Stay with CBS 58 on air and online for the latest updates.  

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