Wellington, New Zealand — (METERING.COM) — January 26, 2009 – Water losses are a major problem in New Zealand with water utilities losing up to 18 percent and more of their reticulated water, a new benchmarking survey has found.
The survey – a pilot study as a first step towards a national annual review program – from the New Zealand Water and Wastes Association (NZWWA), reviewed eight organizations of varying sizes, from Christchurch City Council with a population of 348,000 serving almost 162,000 properties to New Plymouth District Council with a population of 72,200 serving just over 33,000 properties.
The jurisdictional land areas also vary, from 9,860 ha at Hamilton City Council up to 334,922 ha at Dunedin City Council.
Three of the utilities reported losses greater than 18 percent – Whangarei District Council at 18.1 percent, Capacity Wellington at 18.3 percent, and Capacity Hutt City at 18.9 percent. Conversely Christchurch City Council reported a loss of 9.4 percent, Dunedin City Council 6.6 percent, and Hamilton City Council the lowest at 3.4 percent.
However, in terms of length, Capacity Wellington was found to have the greatest loss at 565,852 m3/100 km. This is almost 50 percent larger than the next highest, Capacity Hutt City at 386,499 m3/100 km, and almost a factor ten larger than the lowest, Hamilton City Council at 61,843 m3/100 km. Hamilton also reported the lowest non-revenue water at under 1.2 million m3, much less than the 6.4 million m3 at Christchurch and the 6.3 million m3 at Wellington.
Losses include both “real” losses through leaks and bursts, as well as “apparent” losses, such as metering errors, unauthorized use, and authorized but un-billed consumption such as fire fighting and routine maintenance.
The survey assessed a range of selected measures relating to performance in the environmental, social and economic areas of water supply, wastewater and stormwater services.
All of the utilities reported having water meters, raging from 128,238 meters at Christchurch City Council to 113 meters at Capacity Hutt City. However, the price of water is charged to customers in various ways by the eight utilities, including minimum pricing, fixed charges (uniform annual charge) and user charges (volumetric charging). For comparison customers with an annual consumption of 200 m3 could pay from $117 (US$62) to Christchurch City Council up to $350 (US$185) to Whangarei District Council.
The utilities also reported utilizing a range of procedures to respond to customer complaints. For example Christchurch City Council required a 5 day response to any letter, while most calls for service (not necessarily complaints) were responded to within 1 hour, 1 day or 3 days depending on the nature of the service required. Dunedin City Council, Tauranga City Council and New Plymouth District Council all reported a 100 percent response to complaints within 10 days.