Unregulated river systems are those that do not have large structures which provide water for extractive uses. In these systems, Bulk Entitlements (BEs) are issued to water authorities that divert directly from rivers. In addition, there are a large number of private diverters who are licensed to extract water by pumping directly from rivers. Currently, the majority of this water is taken during the summer months, often causing ecological stress through major loss of habitat and poor water quality.

Management of unregulated systems is based on three factors:

• recognition of the ecological stress caused by diversions, particularly by existing summer diversions
• recognition of the need for reliability of supply for consumptive use
• the need for a risk-based approach to management of diversions where the level of management effort increases with the level of environmental risk.

Due to the ecological stress caused by summer diversions, for the past 15 years new summer diversion licences have generally not been issued.

Priority Categories

The risk-based management approach classifies streams into three management priority categories based on:

• environmental/ecological values that need to be protected or enhanced
• the amount of water authorised to be taken and the amount of water used in the area
• the history of management difficulty in terms of water shortages
• the likelihood of further demand for water
• the need to protect downstream entitlements
• the Permissible Annual Volume (the volume of entitlements that can be safely diverted) for the area.

Streams with a high environmental value and a high level of risk are given the highest level of management effort – the development of a community-based Streamflow Management Plan (SFMP).

Streams where either the level of risk or the values are not as high are categorised as medium priority. These streams are intended to eventually be managed using a SFMP but are currently a lower priority for SFMP development. In the interim, they are managed by management rules directed at relieving summer ecological stress, using trading to improve environmental flow regimes, managing winter diversions within a sustainable limit and collecting data on water use to input to the eventual SFMP process.Streams where the level of risk is clearly low are also subject to management rules which protect their current values and which therefore address issues including the protection of summer flows and freshes, managing winter diversions within a sustainable limit, and trading.

Streams where the level of risk is clearly low are also subject to management rules which protect their current values and which therefore address issues including the protection of summer flows and freshes, managing winter diversions within a sustainable limit, and trading.