Water meters have already uncovered leaks large enough to fill tankers as installation rolls out across the district, according to Kapiti Coast District Council.
Mayor Jenny Rowan said council staff had told her that a 31,000-litre a day leak was discovered when a meter was installed on a double property.
The first residential water meters were installed in August, with installation work set to continue until December 2013.
"New water meters installed at other private addresses have shown up water leaks of 26,000 litres a day, 19,500 litres a day, and numerous leaks in the 4000 to 9000-litre range.
"This is only the start. As more and more meters are installed and property owners check the readings against household use, more leaks will be discovered."
Ms Rowan said the 31,000-litre leak was equivalent to two large tankers of water pouring from the public system each day.
JB's Environmental owner John Matangi said meters have revealed how leaks can be invisible from the surface of properties.
Mr Matangi's Star Fish Kapiti shop in Te Roto Dr is already metered as a commercial operation, but kept below the trigger for charging till its last bill.
"Then we got this big bill for just over $1000 for three months . . . and we thought 'that's not good'."
Mr Matangi said there were no visible signs of leakage anywhere on the property. However, the shop was billed for about 13,000 litres of extra use each day.
"What we did was once we'd finished work at the end of the day, we took a meter reading and read it again in the morning and it [the bill] was pretty much bang on."
Mr Matangi said the leak has been bypassed by a more direct link to the water supply system.
"While I'm not pro-water meters, I am pro-conservation and being mindful of how we use our resources," he said.
Mr Matangi also makes money out of delivering 16,000-litre tanker loads of water to householders wanting to top up rainwater-fed water tanks.
He laughed when it was suggested he might have been filling the tanker from the leaking pipe. ''Nice try,'' said.
Council infrastructure group manager Sean Mallon said information on reading meters and the obligations for the council and property owners is outlined in a new brochure delivered to properties where meters had been installed.
"The meters are very easy to read. Once a meter is installed, I would urge the resident to turn off all the appliances on their property and then check the meter to see whether the counter needle on the meter is still turning. If it is, then you probably have a leak."
The council would not reveal the properties where the leaks were discovered, citing privacy.
- Kapiti Observer
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