Commerce Commission will not step in over Wellington water bills

The Commerce Commission has confirmed it will not step in to hold down Wellington water bills at this time.

Bills charged through Wellington's water agency, Tiaki Wai, are rising by an average of 13.3 percent this year and are projected to reach more than $6000 a year within a decade, according to RNZ.

Commission chairperson John Small said affordability was not within the Commission's mandate. He said its role was to ensure assets were managed properly and prices were not out of line with costs.

Small said Tiaki Wai's costs far exceeded the money it currently collects from Wellingtonians. He said there was currently no sign its revenue was out of line with its costs, given the investment the agency needed to make.

The position follows calls from Wellington Mayor Andrew Little and deputy mayor Ben McNulty for the Commission to regulate water prices.

Small said it was not his understanding that Tiaki Wai was technically insolvent.

The Commission, which regulates water supply and wastewater services, is instead imposing performance requirement rules on Tiaki Wai. The rules will require regular reporting on progress to upgrade regional infrastructure.

Tiaki Wai chief executive Michael Brewster said about 12.5 kilometres of pipe had been renewed in the first three months, with the agency on track for between 35km and 49km this year.

The Commission has previously said its economic regulation of Wellington's water services does not cover funding decisions and billing. It finalised information disclosure rules for councils and water organisations in February to improve transparency around performance and spending.