Down the gurgler


Water metering is on the horizon with Queenstown district properties using five bathtubs full more a day each than the national average.

Results of a 17-month water meter trial by the resort’s council show on average each connection used 1100 litres per day.

That’s a whopping 400 litres above the national average.

More than 900 properties were monitored during the trial, including residential, commercial, lifestyle block and council properties.

Each one is a single connection.

And the council’s chief engineer Ulrich Glasner says much of the water is just leaking away.

“Private leaks are high – 45 per cent of meters had a leak at some point during the trial.”

One property was metered at using 1.5 million litres of water a month – two-thirds of an Olympic-sized swimming pool.

“Once the leak was fixed that was reduced to 2000 litres a month.”

The trial ran from April 2015 to September 2016.

Water consumption is a $50 million question for Queenstown’s new council.

Infrastructure boss Peter Hansby said back in December capital works costing that much could be deferred for at least 15 years if demand can be reduced by 20 per cent.

Glasner says: “Reduction in demand of between 25-39 per cent could be achieved potentially with metering and charging.

“Without charging we’d be unlikely to see demand drop significantly.”

That capital works programme will be reviewed in preparation for the next 10-year plan, in 2018.

The outgoing council was briefed on the findings in September.

A report and recommendations are now being prepared for the new council. It will take the final decision on whether to introduce charging.

The meter reading data was collected by Veolia and the council, and stored in the council data warehouse.

Arrowtown-based infrastructure consultants Rationale analysed the data.

It found section size is linked with water consumption, with large residential sections using significant volumes.

“That’s assumed to be irrigation use or leaks,” Glasner says.

It also found the drive-by readings worked well for 336 newly-installed automatic meters.

The council also conducted a ‘water use behaviour’ survey.

“Sixty-two per cent of respondents thought water charges should be based on actual consumption.”

But Glasner says lake algae in the Queenstown and Wanaka water supply needs to be addressed before full-scale metering is considered.

Glasner says the trial meters remain in use.

“We are continuing to read at this stage as they are providing valuable ongoing information about water use and trends.”