The Central Otago District Council lifted the notice four hours after issuing it, at 1pm and was praised for its swift action.
A Central Otago District Council spokeswoman advised people in the area to flush a tap for about one to two minutes before drinking water again.
She thanked the community for its support in spreading the message while it worked to understand what was going on and resolve the issue.
The council issued a warning about 9am telling Roxburgh residents to not to drink water from the town’s supply, even if boiled, because of an issue at its reservoir.
The spokeswoman said it appreciated there was concern in the community about the water supply and for those who had consumed water after 8.20am yesterday morning.
She said sensors were triggered just before 8am at the reservoir, and it would have taken at least 30 minutes for the overchlorinated water to have reached the town.
The council believed upgrades being done on the culvert at Pumphouse Creek triggered a big dose of chlorine to enter the reservoir.
Southern District Health Board medical officer of health Dr Susan Jack said their drinking water assessors advised the council that the chlorine levels reported should not cause any significant health effects although the water could have had an odour.
People might have experienced minor irritation to eyes, skin and mucous membranes.
The alkaline water could corrode pipes so flushing was recommended, she said.
During the do-not-consume notice the council advised using bottled water or water from tankers that were stationed at Roxburgh Area School school and Roxburgh Medical Centre.
This applied to water for all drinking, making up formula, juices and ice, washing fruits and vegetables, other cooking needs, and brushing teeth.
Boiling would not make it safe.
Schools, businesses and people on a vulnerable persons list had been contacted.
At Roxburgh Area School staff were taking no chances and acted swiftly after principal Paul McDowall was called by a Fulton Hogan staff member about 9am.
The tank of drinking water arrived about 30 minutes later.
"It’s upsetting when things happen at any school, and the welfare of students is the priority," the principal said.
They made sure pupils did not use taps and emptied out water bottles filled at home before going to school, he said.
