A boil water alert for Dunedin is likely to be lifted tomorrow, the city council says, after a second round of results came back clear.
Thousands of people have been warned to boil their water since water from a disused reservoir was mistakenly let into the city's pipes on Monday.
Dunedin City Council had been expecting to wait until Saturday to allow people to drink tap water in the central and north of the city.
The first test results came back within normal drinking standards last night, and chief executive Sue Bidrose said another round of tests had come back clear today.
"We remain hopeful that we might be able to lift that notice on the water for the pipes tomorrow because things very quickly have returned to normal and we're getting good results out of our pipes."
Ms Bidrose said one test from the disused Ross Creek reservoir had shown some bacteria, but the level was within the standard for being safe to swim in.
A third consecutive day of clear tests will be required before the council lifts the boil water notice.