Prerequisite policy measures

Prerequisite policy measures are legislative and operational rule changes that seek to maximise the beneficial outcome of water recovered for the environment under the Basin Plan. They provide secure and enduring arrangements for the efficient and effective use of held environmental water. PPMs improve the use and accounting of water delivered for the environment in the southern-connected Basin.

Why do we have prerequisite policy measures?

When the Murray-Darling Basin Authority set the Sustainable Diversion Limit(s), they assumed that certain measures would be in place to maximise the benefits provided by environmental water. Without these measures, larger quantities of water would need to be recovered to achieve the same results. These measures are known as prerequisite policy measures.

Prerequisite policy measures (PPMs) apply only to Held Environmental Water (HEW) in the regulated Murray Lower Darling and Murrumbidgee river systems. They will allow HEW to be used more effectively and flexibly, by letting it be used across multiple sites, and allowing water for the environment to be released on top of natural flow events.

The PPMs will mean HEW can be used more efficiently, maximising the benefits of water recovered for the environment, while maintaining the reliability of other licence holders.

Under the Basin Plan, PPMs must be in place by 30 June 2019. The MDBA's information on prerequisite policy measures is also available.

What are the PPMs?

There are two prerequisite policy measures, both of which will be put in place in the regulated Murray Lower Darling and Murrumbidgee River systems. These are:

  • Environmental flow reuse. If water used in an environmental event returns to the river, it’s recognised as a returned flow and can be used for downstream environmental purposes.
  • Piggybacking, or directed release. Environmental water holders can order water from storage during a flow event, and the water is released on top of the event.

More details on the PPMs and how they will be implemented in each system is provided in the factsheets and procedure manuals below.

What is Held Environmental Water?

Held Environmental Water is water that has been allocated to water licences which are held exclusively for environmental use. Both the NSW and Commonwealth governments have acquired water licences for environmental purposes in regulated, unregulated and groundwater sources.

PPMs will apply to HEW in the regulated NSW Murray and Lower Darling and Murrumbidgee river systems. They apply as a result of the supply measure projects in these valleys. These projects make it important for HEW to be able to be delivered in the way the projects anticipate.

Working with stakeholders

To successfully use PPMs to deliver HEW, we will consult with stakeholders on how we complete watering actions and the adequacy of mitigation measures. This will ensure our approach is transparent and appropriate.

Our key stakeholders include environmental water holders, primarily the Commonwealth Environmental Water Holder, the NSW Environmental Water Manager (OEH), WaterNSW, the Natural Resources Access Regulator, the Murray Darling Basin Authority and licensed water users or their representative groups.

Details of the consultation requirements are provided in the PPMs Procedures Manuals.

Annual evaluation and review

The management and delivery of environmental water is still evolving. We’ll use adaptive management to learn, refine and continuously improve the framework for PPMs.

Each year, the NSW Environmental Water Manager and WaterNSW are both required to report on environmental watering actions that used PPMs. We’ll use these reports to evaluate and review PPMs to inform and improve the way we manage PPMs.

Two annual reviews of PPM implementation in NSW have been completed: