The Mersey Water Management Plan was adopted, under section 28 of the
Water Management Act 1999, on 18 August 2005 and took effect on 31 August 2005.
The purpose of the Plan is to provide a framework for managing the water resources of the Mersey River Catchment in accordance with the objectives of the
Water Management Act 1999 
Mersey Water Management Plan (1003 KB)
Please note: Due to its size, 'Figure One - Catchment of the Mersey River' is not included in the above Plan document.
Catchment of the Mersey River (2Mb)
Review of the Mersey Water Management Plan
The Department of Natural Resources and Environment Tasmania (NRE Tas) has now completed the preparation of a Draft Amended Mersey River Catchment Water Management Plan 2023.
Amendments to the Mersey Water Management Plan 2005 have been carefully considered and developed over the past three years informed by feedback from key stakeholders through the Mersey Consultative Group. The Draft Amended Water Management Plan has been prepared by NRE Tasmania and was made available for public comment between 19 July and 18 September 2023 (the public comment period is now closed). The submissions received on the Draft Amended Plan are now being considered through the remaining stages of the statutory plan review process.
To see the Draft Amended Mersey Water Management Plan and for more details of the review process see the link below.
Rules under the Mersey Water Management Plan from 1 October 2023 to 1 May 2024
The access rules that will apply under the Mersey Water Management Plan from 1 November 2023 to 1 May 2024 are the same to those tested under trial over the last summer irrigation season.
Now that Hydro Tasmania are applying a constant minimum environmental release the reduced cease-to-take previously applied is no longer necessary. Assessments undertaken as part of the Plan review process, have shown that this change will maintain the same reliability of access similar to that experienced in dry periods in the past. The arrangements for this season are listed below:
- Hydro Tasmania will continue to maintain a constant environmental release of 160 ML/day from Lake Parangana with the flow release measured at the dam outlet.
- The cease-to-take measured at Mersey River at Shale Road stream flow gauging station will remain at 370 ML/day for October, 260 ML/day for November; and be 195 ML/day for 1 December to 1 May.
- The four-stage restriction protocol that was applied last year will remain in place with no change, as presented in the Table below. The restriction protocol progressively restricts access based on surety levels (priority of access) when flow available above the Cease-to-take is not able to meet 100% of demand.
Staged restriction thresholds for the Mersey River catchment for 1 October to 1 May, as measured at the Mersey River at Shale Road stream flow gauging station.
A general warning will be issued within 10 ML/day of the Stage 1 restriction.
Stage 1
| Cease-to-take plus 30 ML/day
| 400 | 290 | 225 | 50% Ban on Surety Level 6 takes
Surety Level 5 limited to no more than the Maximum Daily Take
|
Stage 2
| Cease-to-take plus 20 ML/day
| 390 | 280 | 215 | Ban on all Surety Level 6 takes
Surety Level 5 limited to no more than the Maximum Daily Take
|
Stage 3
| Cease-to-take plus 10 ML/day
| 380 | 270 | 205 | 50% ban on all Surety Level 5 takes
|
Stage 4
| Cease-to-take | 370 | 260 | 195 | Ban on all Surety Level 5 and 6 takes*
|
*All flows into a dam must be passed downstream (where dam outlet structures permit).