Wellington, New Zealand --- (METERING.COM) --- July 27, 2009 - On environmental, economic and social equity grounds the case for water metering and volumetric charging for domestic dwellings is compelling, says Water New Zealand in a new policy statement.

Saying it supports the introduction of metering and direct volumetric charges for domestic dwellings connected to local authority reticulated water schemes, Water New Zealand (formerly the New Zealand Water and Wastes Association) says these tools assist in the management of water demand by reducing household use and the volume of wastewater requiring transportation and treatment.

Moreover, metering and volumetric charging is also the fairest way of recovering the cost of supplying these services.

The organization notes that metering and volumetric charging for domestic water supply is currently fully employed by 11 of the 73 territorial local authorities (TLAs) in New Zealand. A further eight TLAs have metering in some areas of their respective jurisdictions and one TLA requires the installation of meters at domestic dwellings but does not impose volumetric charging.

The average per capita daily water use across TLAs that apply volumetric charging for water supply is typically in the region of 200 l. This contrasts with figures of over 700 l from some TLAs without metering and volumetric charging.

The introduction of metering and volumetric charging will enable effective and cost efficient monitoring of domestic water use, including monitoring of variations in demand at different times of the year, says Water New Zealand. Using this tool Nelson City reported a 37 percent reduction in peak summer demand periods.
Cost-benefit analyses of water metering and volumetric charging also indicate there is a high rate of return in areas where large capital expenditure is required on the treatment facilities to keep up with demand. One TLA has reported that the introduction of metering delayed estimated capital expenditure of NZ$75 million (US$49.2 million) on water supply investments for around 10-12 years. More recently the same TLA has estimated that $30 million to $40 million (US$19.7 million to US$26.3 million) of wastewater treatment investment can now be deferred for up to eight years. These savings have resulted from the $9.7 million (US$6.4 million) cost of installing metering in every household.
Smaller water suppliers with fewer available resources may not see the same high rates of return with universal metering, as the initial capital, maintenance and reading costs can outweigh the benefits in these areas. An alternative for such suppliers may be to apply metering for users of extra-ordinary or excessive amounts of water.

For larger water suppliers, however, metering provides a strong signal to users to conserve water and reduce wastage. Customers will have an increased awareness of their water use, and save money accordingly. While uniform annual charges to reticulated domestic dwellings can lead to high volume users being cross subsidized by low use householders, metering provides an equitable method for charging consumers as they are charged for water used rather than having to pay a fixed annual fee.

Water New Zealand also notes that as with other charging methodologies, direct volumetric charging may put financial pressure on some household budgets. However, while affordability is not the responsibility of water utilities, as corporate citizens it is appropriate for these entities and Water New Zealand to work with relevant agencies to develop guidelines for dealing with customer groups that are vulnerable under this and other charging regimes.