Timeline of OWASA and Orange Co. Health Department actions in February water emergency

Timeline of Actions Taken by OWASA and the Orange County Health Department in Regards to the February 2017 Water Emergency

On February 2, 2017, OWASA’s water supply was disrupted by an over-feed of fluoride at its water treatment plant on the west side of Carrboro; the contaminated water was contained within an onsite storage facility (the clearwell) and was not introduced to the public water distribution system. Water was initially supplied by the City of Durham and later by Chatham County interconnections to meet demand and maintain adequate storage volumes while the water treatment plant was out of service.


On February 3, 2017, in a separate but compounding event, a 12-inch water distribution main break occurred on the northeast side of Chapel Hill spilling more than a million gallons of water. Although, the break was quickly isolated, OWASA promptly issued a “DO NOT USE” directive due to concerns about its ability to maintain system pressures for water quality and firefighting needs. Shortly after, the Orange County Health Department issued “DO NOT USE” and “DO NOT DRINK” directives. These directives were not made because of excess fluoride in the drinking water.


Early afternoon on February 4, 2017, after tank levels rebounded and test results confirmed that the water was safe to drink, the “DO NOT USE” and “DO NOT DRINK” directives were lifted. Between then and when the water treatment plant was restored to service on the evening of February 4, 2017, the City of Durham and Chatham County connections continued to supply water to the OWASA distribution system, and OWASA customers were asked to use water only for essential purposes.


The following timeline for particular events during the water emergency is provided to make a record of the events and their timeline during the water emergency. This chronology was prepared from materials available to us as of 10:00 am Wednesday, February 8, 2017, and are subject to amendments and corrections as may be necessary in light of further investigation.

February 2, 2017

3:00 pm

Fluoride overfeed discovered and confirmed by OWASA Water Treatment Plant (WTP) staff

3:22 pm

Finished water pumping from WTP to distribution system is stopped

3:28 pm

NC Department of Environmental Quality, Public Water Supply (PWS) notified

5:09 pm

First Durham interconnection activated to maintain system pressure and meet system demands

6:00 pm

News release issued by OWASA advising of the event and requesting conservation

7:22 pm

Began pumping over-fluoridated water from clearwell directly to OWASA Wastewater Treatment Plant (WWTP)

8:00 pm

Notified PWS of ongoing actions to empty clearwell

11:00 pm

Second OWASA news release with additional information regarding event

February 3, 2017


8:00 am

Third OWASA news release with additional call for conservation

9:30 am

Began activation measures for second interconnection with Durham on Highway 54

9:30 am

Began flushing interconnection with Chatham County

9:30 am

Began flushing interconnection with Hillsborough

10:13 am

OWASA water main broke in northeast Chapel Hill

11:00 am

OWASA requested activation of the Orange County Emergency Operations Center (EOC) and Water Emergency Team Partners

11:30 am

OWASA issued “DO NOT USE” directive to customers to prevent contamination and protect emergency supply

11:30 am

Water main break isolated by locating and closing control valves

12:00 pm

Repair work began on water main break

2:00 pm

Orange County Health Department (OCHD) issued “DO NOT USE” and
“DO NOT DRINK” directives

2:00 pm

Second Durham interconnection activated to maintain pressure and storage

4:00 pm

Press briefing by Water Emergency Team Partners and OWASA at Orange County Emergency Operation Center

5:15 pm

Chatham County interconnection activated

10:24 pm

Backup pump delivered to primary Durham interconnect and prepared for service

February 4, 2017


1:30 am

Third backup pump activated for dewatering clearwell

9:00 am

Began re-filling clearwell with non-fluoridated filtered water

10:30 am

Water main repaired; flushing began to ensure water quality

12:34 pm

All distribution samples found to be clear and absent of bacteriological indicators

2:24 pm

“DO NOT USE” and “DO NOT DRINK” directives lifted by OCHD and OWASA

2:30 pm

Joint news release on safety of drinking water, progress on repairs, and request for conservation

3:00 pm

Press briefing on progress at Orange County Emergency Operation Center

3:30 pm

Boil water advisory issued for customers near line break

5:56 pm

Interconnection with Chatham County deactivated

6:30 pm

Discharge from clearwell completed

6:37 pm

OWASA Water Treatment Plant back in full operation

7:47 pm

Second interconnection with Durham deactivated

9:04 pm

Primary interconnection with Durham deactivated

In order to ensure that critical public health messages reached as many of our customers as possible, multiple (and sometimes overlapping) channels were used to release news of changes in status.

Colleen Bridger, MPH, PhD                                        Ed Kerwin

Orange County Health Director                                 OWASA Executive Director