School principal Andrew FitzSimons said the problem was expected to be fixed before 8am but once it became apparent it was more serious, he was left with little choice but to send all students home.

“The water that powers our fire hydrants has sprung a leak and is under a lot of pressure. We believe that it has affected the pipe beside it, which is our potable water,” Mr FitzSimons said.

“It is only relatively new but apparently it is badly designed, as the pipes are too close together.

“We believed it was going to be fixed by 8am but it has become more and more complex as they dig and at about 8.30am I decided we just had to evacuate.”

The principal said every effort was made to stay open.

“Our deputy went to Woolies and bought some bottled waters, which Woolies doubled and donated to us free of charge. It was a wonderfully generous thing Woolworths did but in the end we had to evacuate in any case,” he said.

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But while the students got an unexpected day off, it’s not the case for parents.

“I’ve now got 10 portaloos on site and our parent teacher night for years 7 and 8 is still on tonight as planned,” Mr FitzSimons said.

“We’re actually very chuffed as this is the highest participation we’ve ever had. We’ve got just under 50 per cent of parents who have booked in for appointments.

“All the staff will be here for discussions and we are all elated that such a high proportion of parents have made it a priority.”