Mysterious leak stumps council

SHARE

Mystery surrounds an area of the Roxburgh Gorge Trail where water is trickling from an unknown source at a rate of 4 litres per minute.
Central Otago Clutha Trails co-director Barrie Wills said the water had been running above and alongside the track since about July, but despite investigations it was not known exactly what the cause was or from where it was coming.
The water was running down a bank, above the track, and appeared to be coming from a source in Old Bridge Rd, in Alexandra.
Dr Wills said it was possibly the result of a leaking spring, or a problem with a nearby property’s water main.
‘‘We’d just like to see it fixed. It’s a real mess.’’
The problem was discovered in July last year after flooding.
The Central Otago District Council arranged specialist contractor Detection Services to check the reticulation in Old Bridge Rd and O’Neill Cres for leaks.
Infrastructure services executive manager Julie Muir said three water leaks in the council water supply pipes were discovered and repaired in July and a private property owner was also advised of a leak on their property.
Two further leaks in council reticulation were repaired in December and several leaks on private land were discussed with property owners, which they were advised to repair.
Meter reading for properties in December showed nothing that would indicate water leaks on private property.
Detection Services assessed the area again this month to confirm there were no more leaks in council reticulation.
‘‘Findings of this work are not yet known,’’ Ms Muir said.
‘‘We believe that the remaining problem could be a result of ground water in the area.’’
Water tests showed no sign of chlorine.
‘‘We believe the appropriate step is to monitor the situation over the drier summer months, once we get a prolonged dry period, to see if the wet spots dry.
‘‘If it dries over the summer, then that will confirm that it is groundwater and not a leak from the council water supply.’’
Roxburgh Gorge Trails Trust members had also attempted to determine where the water was coming from.
Dr Wills did a test to find out how quickly the running water would fill a 2 litre ice-cream container; it took just 30 seconds.
‘‘That’s just what is running on the surface. It could be five or six times as much water coming out of the bank.’’
If the issue was not resolved soon, it could create severe problems — particularly if the bank started to slump below neighbouring houses, he said.
‘‘It has been wet for ages, so that does concern me.’’
Old Bridge Rd resident Russell Butt, whose property sits above the bank, said the problem had been ongoing for several years.
It was temporarily fixed about three years ago, but after returning from holiday at Christmas he discovered the water was back, flooding parts of his lawn and garden, he said.
‘‘I am concerned [because] I don’t know how much damage it is doing under our house,’’ he said.
‘‘This house has already moved over the years and the water is already running underneath it. Is it going to move some more?’’
He estimated there were about four houses on the bank that could be compromised.