Ord

Control of the taking of water is exercised by the Department of Water through allocation planning and its surface and groundwater licensing arrangements. Water can only be taken from designated surface and groundwater management areas within the region when a licence is issued. Licencees that have a licenced allocation above the minimum threshold of 5 ML per annum are required to have approved meters for the taking of water and report the amount of water taken on a yearly basis.

Ord River licences include a condition that specifies that the Department of Water may limit the amount of water which may be taken at times of inadequate supply. Restrictions on irrigation and releases for the environment commence when storage levels reach 20% of the full supply level of Lake Argyle.

The release of water for hydro-electricity generation is constrained by a set of operating rules. Under the original water supply agreement with the power station operators (1994), the station is guaranteed to have enough water released to enable a minimum of 210 GWh/yr to be generated. The minimum amount is based on the following water levels being maintained in Lake Argyle:

• in March, the period that historically has the highest storage, 87% of the full supply level
• in December, the period that historically has the lowest storage, 66% of the full supply level.

When the water level in Lake Argyle is above these levels, electricity generation is only limited by the installed capacity of the power station.

Under the Rights in Water and Irrigation Act 1914, a licence is required to abstract water in proclaimed surface water and groundwater areas. The Act also necessitates all artesian bores to be licenced for their construction and the taking of water.

Licences to abstract water are administered by the Department of Water. Licences specify the conditions, length of tenure and volume of water that may be taken on an annual basis. The volume is referred to as the annual water entitlement.

The Rights in Water and Irrigation Act 1914 has provisions for ‘riparian right’ use of water that is an incident of land ownership and no licence is required to use water under these provisions. Department-gazetted exemption orders also make exceptions for having to apply for and be granted a licenced water entitlement for the following non-artesian groundwater uses:

• taking water for fire-fighting purposes
• watering cattle or other stock, other than those being raised under intensive conditions
• domestic garden and lawn irrigation (not exceeding 0.2 ha)
• short-term dewatering activities taking small volumes of groundwater from the water table aquifer.

Self-supply licencees are entitled to take up to the maximum annual amount prescribed in the licence. This volume can be used at the licencee’s discretion during the licence year except where restrictions are placed. Any unused allocation is forfeited and cannot be carried over to a subsequent licence year.

Further conditions apply for larger entitlements and are specified in an operating strategy attached to the licence. Implementation of the strategy is a condition of the licence. Operating strategies also describe how the licencee intends to implement the conditions and list commitments that the licencee is to undertake. They are jointly prepared and approved by the licencee and the Department of Water.

Licencees are required to have approved meters for the taking of water and are expected to report annually on the amount of water abstracted. The Rights in Water and Irrigation Act 1914 has provisions dealing with licencees that abstract more than their allocation.

Water licenses

Under the Rights in Water and Irrigation Act 1914:

• The Water Corporation holds a licence that regulates their operation of the Ord River Dam and the Kununurra Diversion Dam. While the licence authorises the storage of water and establishes conditions for the release of water from storage, it does not authorise the diversion of water from the Ord River and therefore has a zero water entitlement. The licence sets conditions on how water may be released from the storage for hydro-electricity generation and obliges the Water Corporation to operate storage levels so that the environmental water provisions for the lower Ord River are maintained.
• The Ord Irrigation Cooperative holds a licence for the diversion of an average of 335 GL/yr from Lake Kununurra until March 2014. The licence is issued for the purposes of distribution and supply to irrigators for irrigation use and for nonpotable commercial uses, in areas serviced by the Stage 1 channel systems of the district. The annual entitlement includes provision for development of 1390 ha (gross land area) known as Green location.

The Ord River Water Management Plan (2006) sets down sustainable diversion limits for entitlements from the Ord River. Since 2006, the understanding of the hydrology of the Ord River was updated and comprehensive environmental water requirements developed for the lower Ord River. The Department of Water revised the areas it employs to manage surface water use in the region and additional limits were set for the upper Ord River and Dunham River catchments.

Current annual water entitlement limits and annual entitlements granted as at 2009–10 are shown in Table R1.

Table R1. Annual water entitlements limits for surface water resource areas of the Ord River

Annual water allocations are the quantity of water available after environmental water provisions and domestic requirements are met and are determined and announced by the Department of Water in April each year.

To date, the Department of Water has not announced an annual water allocation less than the annual water entitlement.

Water market rules: interstate trading

The Rights in Water and Irrigation Act 1914 regulates the trading and transferring of licences in Western Australia. The powers of the Act are confined to Western Australia; therefore interstate trade is not permitted.

Water market rules: inter-valley trading

The Rights in Water and Irrigation Act 1914 permits the trading or transferring of licences within the same water management area, subject to compliance with the Act and other administrative issues.

Inter-valley trading of water entitlements did not occur in the Ord region during the reporting period.

The Articles of Association of the Ord Irrigation Cooperative provide for trade of on-farm water entitlements between members. Details of trades are provided to the Department of Water in an annual report. No trades occurred to date. 

Restrictions on trade

No restrictions on trades or transfers in addition to those described previously were in place during 2009–10.