Officials with the town of Harbour Grace say the town's basic water-chlorination system is functioning, but it will take another four days to complete tests to clear the town water supply for drinking.

Vandals broke into the town's water treatment buildings late Friday night or early Saturday morning and did significant damage to the town's water chlorination system.

Don Coombs, the mayor of Harbour Grace, said the town's basic chlorination system had been working since Sunday.

"It's a precautionary thing," said Coombs. "There is chlorine going in. Is it the right amount of levels? Is it going through properly? Those are the things we have to take care of right now."

Coombs has urged residents to err on the side of caution and boil their drinking water until the town lifts the ban.

Damage substantial, says mayor

Meanwhile, Coombs said damage to the two water treatment buildings was substantial.

He said the water meter on the outside of one of the buildings was broken. He said vandals entered one building by forcing open a door, and entered the other building by smashing the roof with an axe.

"There's nothing in the buildings for people who go in there and don't know what they're at," said Coombs.

"It's a dangerous situation of course, to go into a chlorine plant. Fortunately, no one was hurt."

Coombs said it will cost about $20,000 to fix the damage at the plant, and he said anyone who has information about the incident should contact the town office or the Harbour Grace detachment of the RCMP.