River modelling for Tasmania Volume 3: the Pipers ......Hydro Tasmania Consulting: Fiona Ling, Mark Willis, James Bennett, Vila Gupta, Kim Robinson, Kiran Paudel and Keiran Jacka Sinclair

Ling FLN, Gupta V, Willis M, Bennett JC, Robinson KA, Paudel K, Post DA and Marvanek S

A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project

December 2009

River modelling for Tasmania Volume 3: the Pipers-Ringarooma region

Contributors

Tasmania Sustainable Yields Project acknowledgments

Prepared by CSIRO for the Australian Government under the Water for the Future Plan of the Australian Government Department of the Environment, Water, Heritage and the Arts. Important aspects of the work were undertaken by the Tasmanian Department of Primary Industries, Parks, Water and Environment; Hydro Tasmania Consulting; Sinclair Knight Merz; and Aquaterra Consulting.

Project guidance was provided by the Steering Committee: Australian Government Department of the Environment, Water, Heritage and the Arts; Tasmanian Department of Primary Industries, Parks, Water and Environment; CSIRO Water for a Healthy Country Flagship; and the Bureau of Meteorology.

Scientific rigour for this report was ensured by external reviewers, Tony Jakeman, Murray Peel and Peter Davies.

Valuable input was provided by the Sustainable Yields Technical Reference Panel: CSIRO Land and Water; Australian Government Department of the Environment, Water, Heritage and the Arts; Tasmanian Department of Primary Industries, Parks, Water, and Environment; Western Australian Department of Water; and the National Water Commission.

We acknowledge the Tasmanian Department of Primary Industries, Parks, Water, and Environment for providing the original TasCatch models for use in the current project, and for assistance in providing cease-to-take rules, operating rules for storages, and environmental flows.

We acknowledge input from the following individuals: Richard McLoughlin, Alan Harradine, Louise Minty, Ian Prosser, Patricia Please, Martin Read, Rod Oliver, Dugald Black, Ian Loh, Albert Van Dijk, Geoff Podger, Scott Keyworth, Helen Beringen, Mary Mulcahy, Paul Jupp, Amanda Sutton, Josie Grayson, Melanie Jose, Ali Wood, Peter Fitch, Wenju Cai, Ken Currie, Eric Lam, Imogen Fullagar, Nathan Bindoff, Stuart Corney, Mike Pook and Richard Davis.

Tasmania Sustainable Yields Project disclaimers

Derived from or contains data and/or software provided by the Organisations. The Organisations give no warranty in relation to the data and/or software they provided (including accuracy, reliability, completeness, currency or suitability) and accept no liability (including without limitation, liability in negligence) for any loss, damage or costs (including consequential damage) relating to any use or reliance on the data or software including any material derived from that data or software. Data must not be used for direct marketing or be used in breach of the privacy laws. Organisations include: the Tasmanian Department of Primary Industries, Parks, Water, and Environment; Hydro Tasmania Consulting; Sinclair Knight Merz; Aquaterra Consulting; Antarctic Climate and Ecosystems CRC; Tasmanian Irrigation Development Board; Private Forests Tasmania; and the Queensland Department of Environment and Resource Management.

Data on proposed irrigation developments were supplied by the Tasmanian Irrigation Development Board in June 2009. Data on projected increases in commercial forest plantations were provided by Private Forests Tasmania in February 2009.

CSIRO advises that the information contained in this publication comprises general statements based on scientific research. The reader is advised and needs to be aware that such information may be incomplete or unable to be used in any specific situation. No reliance or actions must therefore be made on that information without seeking prior expert professional, scientific and technical advice. To the extent permitted by law, CSIRO (including its employees and consultants) excludes all liability to any person for any consequences, including but not limited to all losses, damages, costs, expenses and any other compensation, arising directly or indirectly from using this publication (in part or in whole) and any information or material contained in it. Data are assumed to be correct as received from the Organisations.

Citation

Ling FLN, Gupta V, Willis M, Bennett JC, Robinson KA, Paudel K, Post DA and Marvanek S (2009) River modelling for Tasmania. Volume 3: the Pipers-Ringarooma region. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Publication Details

Published by CSIRO © 2009 all rights reserved. This work is copyright. Apart from any use as permitted under the Copyright Act 1968, no part may be reproduced by any process without prior written permission from CSIRO.

ISSN 1835-095X

Photo on cover: Great Forester River near Bridport (CSIRO)

Project Management: David Post, Tom Hatton, Mac Kirby, Therese McGillion and Linda Merrin

Report Production: Frances Marston, Susan Cuddy, Maryam Ahmad, William Francis, Becky Schmidt, Siobhan Duffy, Heinz Buettikofer, Alex Dyce, Simon Gallant, Chris Maguire and Ben Wurcker

Project Team: CSIRO: Francis Chiew, Neil Viney, Glenn Harrington, Jin Teng, Ang Yang, Glen Walker, Jack Katzfey, John McGregor, Kim Nguyen, Russell Crosbie, Steve Marvanek, Dewi Kirono, Ian Smith, James McCallum, Mick Hartcher, Freddie Mpelasoka, Jai Vaze, Andrew Freebairn, Janice Bathols, Randal Donohue, Li Lingtao, Tim McVicar and David Kent

Tasmanian Department of Primary Industries, Parks, Water and Environment:

Bryce Graham, Ludovic Schmidt, John Gooderham, Shivaraj Gurung, Miladin Latinovic, Chris Bobbi, Scott Hardie, Tom Krasnicki, Danielle Hardie and Don Rockliff

Hydro Tasmania Consulting: Fiona Ling, Mark Willis, James Bennett, Vila Gupta, Kim Robinson, Kiran Paudel and Keiran Jacka

Sinclair Knight Merz: Stuart Richardson, Dougal Currie, Louise Anders and Vic Waclavik

Aquaterra Consulting: Hugh Middlemis, Joel Georgiou and Katharine Bond

Director’s foreword

Following the November 2006 Summit on the southern Murray-Darling Basin (MDB), the then Prime Minister and MDB

state Premiers commissioned CSIRO to undertake an assessment of sustainable yields of surface and groundwater

systems within the MDB. The project set an international benchmark for rigorous and detailed basin-scale assessment of

the anticipated impacts of climate change, catchment development and increasing groundwater extraction on the

availability and use of water resources.

On 26 March 2008, the Council of Australian Governments (COAG) agreed to expand the CSIRO assessments of

sustainable yield so that, for the first time, Australia would have a comprehensive scientific assessment of water yield in

all major water systems across the country. This would allow a consistent analytical framework for water policy decisions

across the nation. The Tasmania Sustainable Yields Project, together with allied projects for northern Australia and

south-west Western Australia, will provide a nation-wide expansion of the assessments.

The CSIRO Tasmania Sustainable Yields Project is providing critical information on current and likely future water

availability. This information will help governments, industry and communities consider the environmental, social and

economic aspects of the sustainable use and management of the precious water assets of Tasmania.

The projects are the first rigorous attempt for the regions to estimate the impacts of catchment development, changing

groundwater extraction, climate variability and anticipated climate change, on water resources at a whole-of-region-scale,

explicitly considering the connectivity of surface and groundwater systems. To do this, we are undertaking the most

comprehensive hydrological modelling ever attempted for the region, using rainfall-runoff models, groundwater recharge

models, river system models and groundwater models, and considering all upstream-downstream and surface-

subsurface connections.

To deliver on the projects CSIRO is drawing on the scientific leadership and technical expertise of national and state

government agencies in Queensland, Tasmania, the Northern Territory and Western Australia, as well as Australia’s

leading industry consultants. The projects are dependent on the cooperative participation of over 50 government and

private sector organisations. The projects have established a comprehensive but efficient process of internal and

external quality assurance on all the work performed and all the results delivered, including advice from senior academic,

industry and government experts.

The projects are led by the Water for a Healthy Country Flagship, a CSIRO-led research initiative established to deliver

the science required for sustainable management of water resources in Australia. By building the capacity and capability

required to deliver on this ambitious goal, the Flagship is ideally positioned to accept the challenge presented by this

complex integrative project.

CSIRO has given the Sustainable Yields Projects its highest priority. It is in that context that I am very pleased and proud

to commend this report to the Australian Government.

Dr Tom Hatton

Director, Water for a Healthy Country

National Research Flagships

CSIRO

© CSIRO 2009 River modelling for Tasmania. Volume 3: the Pipers-Ringarooma region ▪ i

Executive summary

This report describes the river system modelling undertaken for the Pipers-Ringarooma region as part of the CSIRO

Tasmania Sustainable Yields Project. The objective of the river system modelling is to estimate flows in river systems

across Tasmania using a consistent Tasmania-wide modelling approach for four scenarios involving a range of climate

conditions and catchment development levels. The four scenarios are:

Scenario A – historical climate (1 January 1924 to 31 December 2007) and current development

Scenario B – recent climate (data from 1 January 1997 to 31 December 2007 were concatenated to make an

84-year sequence) and current development

Scenario C – future climate (84-year sequence scaled for ~2030 conditions) and current development

Scenario D – future climate (84-year sequence scaled for ~2030 conditions) and future development.

In this project, current development is defined as the development at the end of 2007. Future development is defined to

include projected future levels of commercial forestry plantations, irrigation development and groundwater extraction.

This report only considers changes in future development associated with commercial forestry plantations and irrigation

development as these are the only factors which are likely to affect surface water availability in this region.

River system models were developed for each catchment to describe current infrastructure, water demands and water

management rules. These models were used to assess the implications of changed inflows for water availability and the

reliability of water supply to users. The models are node-link network models developed in Hydstra and they include

water allocations and extractions, streamflow routing and environmental flows. Gridded runoff, rainfall and areal potential

evapotranspiration were inputs to the models. The models were run on a daily time step and the runoff from each

subcatchment was routed through the river network to the next subcatchment downstream.

Over the historical period (1924 to 2007), the Pipers-Ringarooma region had a total mean annual flow of 2264 GL/year,

and a low level of extraction with a mean annual extraction of 79 GL/year (3.5 percent of total water in the region). The

level of extraction varies between catchments up to a maximum of 9 percent of the total mean annual flow in the Great

Forester-Brid catchment. The volume of allocated water varies each year in many catchments, due to restriction rules

which limit extractions during periods of low flow.

Under the current level of development, the volume of water extracted in the region is not expected to reduce

significantly under the future climate (Scenario C) relative to the historical climate (Scenario A). Extractions reduce from

79 GL/year under the historical climate to 75 GL/year under the dry extreme future climate (Scenario Cdry), a reduction

of 4 GL/year (5 percent). The largest impact is in the driest years, with a projected decrease of more than 16 percent in

extracted water in the Great Forester-Brid catchment for the driest one-year period under the dry extreme future climate

relative to the historical climate. By comparison, future climate is projected to have a greater impact on total

end-of-system flows for the region, ranging from a decrease of 3 percent (under the wet extreme future climate

(Scenario Cwet)) to a decrease of 14 percent (under the dry extreme future climate) with a median reduction of 8 percent

(under the median future climate (Scenario Cmid)).

Under the recent climate (Scenario B), the monthly mean discharge is lower than the long-term mean in all catchments in

autumn and winter. The flow duration curves show that flows under the recent climate are generally lower than the

long-term mean over the full range of flows. The volume of extracted water decreases by a mean of 4 GL/year

(5 percent) under the recent climate relative to the historical climate. The non-extracted water decreases by a mean of

535 GL/year (24 percent).

Future development in the Pipers-Ringarooma region includes a projected increase of 147 km2 in commercial forestry

plantations, which will increase total forest cover from 25 percent of the region to 27 percent of the region by 2030. The

increase is spread throughout the region with the largest increases in the north-west. Catchment runoff is projected to

decrease by a maximum of 4.9 percent in the Pipers catchment due to the expansion of forestry plantations under future

development (Scenario D).

Ten irrigation dams are proposed in the region: St Patricks River, Monarch Mines, Brid River, Great Forester River,

Oxberry, Maryvale, Headquarters Road, Little Forester River, Great Musselroe River and Tomahawk River dams. The

extracted volume is 100 percent of the allocated volume for all years for the Brid, Great Forester, Little Forester and

Great Musselroe dams; for more than 90 percent of years for the Maryvale and Headquarters Road dams’ and for more

ii ▪ River modelling for Tasmania. Volume 3: the Pipers-Ringarooma region © CSIRO 2009

than 75 percent of years for the Oxberry Dam. The extracted volume is more than 90 percent of the allocated volume for

75 percent of years for the Tomahawk Dam, but only 40 percent of years for St Patricks River Dam, and less than

20 percent of years for Monarch Mines Dam.

© CSIRO 2009 River modelling for Tasmania. Volume 3: the Pipers-Ringarooma region ▪ iii

Table of contents

1 Introduction ............................................................................................................................ 1

2 Methods .................................................................................................................................. 5 2.1 Allocations and extractions ..............................................................................................................................................5

2.1.1 Water entitlements.............................................................................................................................................5 2.1.2 Unlicensed storages ..........................................................................................................................................6 2.1.3 Unlicensed extractions ......................................................................................................................................7 2.1.4 Environmental flows and releases.....................................................................................................................7 2.1.5 Diversions, storages and model customisation .................................................................................................7

2.2 Future development .........................................................................................................................................................9 2.2.1 Forestry..............................................................................................................................................................9 2.2.2 Irrigation...........................................................................................................................................................10

3 Under historical climate (Scenario A) and future climate (Scenario C)......................... 12 3.1 Water balance and water availability..............................................................................................................................12 3.2 Storage behaviour..........................................................................................................................................................21 3.3 Consumptive water use..................................................................................................................................................22 3.4 End-of-system river flow.................................................................................................................................................34 3.5 Share of available resource ...........................................................................................................................................40

4 Under historical climate (Scenario A) and recent climate (Scenario B) ........................ 45

5 Under future development (Scenario D)............................................................................ 51 5.1 Reliability of proposed irrigation developments..............................................................................................................51 5.2 Hydrologic impacts of future development .....................................................................................................................57

6 Conclusions .......................................................................................................................... 65

7 References............................................................................................................................ 66

Tables

Table 1. Catchments in the Pipers-Ringarooma region.......................................................................................................................4 Table 2. Large storages in the Pipers-Ringarooma region ..................................................................................................................4 Table 3. Department of Primary Industries, Parks, Water and Environment surety descriptions (from DPIPWE, 2009) ....................6 Table 4. Extraction restriction rules......................................................................................................................................................8 Table 5. Capacity and mean annual demand for proposed irrigation developments for Scenario D.................................................10 Table 6. Irrigable area for proposed irrigation developments for Scenario D ....................................................................................10 Table 7. Mean annual water balance for each catchment under scenarios A and C ........................................................................13 Table 8. Storage behaviour under scenarios A and C.......................................................................................................................21 Table 9. Allocated and extracted mean annual flows for catchments under scenarios A and C .......................................................23 Table 10. Mean reliability of high and low priority allocations for catchments under scenarios A and C (annual) ............................24 Table 11. Mean reliability of high and low priority summer allocations under scenarios A and C (summer – October to March inclusive) ............................................................................................................................................................................................25 Table 12. Mean reliability of high and low priority allocations under scenarios A and C (winter – April to September inclusive)......26 Table 13. Indicators of use during dry periods for catchments under Scenario A and change under Scenario C relative to Scenario A .........................................................................................................................................................................................33 Table 14. Peak flows for catchments under scenarios P and A, and under Scenario C relative to Scenario A ................................37 Table 15. Percentage of time end-of-system flow greater than 1 ML/day under scenarios P, A and C ............................................38 Table 16. End-of-system flow for catchments during dry periods under Scenario A, and under Scenario C relative to Scenario A.39 Table 17. Extracted and non-extracted shares of water for the Pipers-Ringarooma region under scenarios A and C (annual) .......40 Table 18. Extracted and non-extracted shares of water for catchments under scenarios A and C (annual).....................................42 Table 19. Extracted and non-extracted shares of water for the Pipers-Ringarooma region under scenarios A and C (summer – October to March inclusive) ...............................................................................................................................................................43 Table 20. Extracted and non-extracted shares of water for catchments under scenarios A and C (summer – October to March inclusive) ............................................................................................................................................................................................43 Table 21. Percentage of water extracted as a proportion of total mean annual flow for catchments under scenarios A and C (annual)..............................................................................................................................................................................................44 Table 22. Percentage of water extracted as a proportion of total mean annual flow for catchments under scenarios A and C (summer – October to March inclusive) .............................................................................................................................................44 Table 23. Percentage of water extracted as a proportion of total end-of-system flow for catchments under scenarios A and C (winter – April to September inclusive) ..............................................................................................................................................44

iv ▪ River modelling for Tasmania. Volume 3: the Pipers-Ringarooma region © CSIRO 2009

Table 24. Mean annual extracted and non-extracted shares of water for the Pipers-Ringarooma region under scenarios A and B 48 Table 25. Extracted and non-extracted shares of water for the Pipers-Ringarooma region under scenarios A and B (summer – October to March inclusive) ...............................................................................................................................................................48 Table 26. Mean annual extracted and non-extracted shares of water for catchments under scenarios A and B..............................49 Table 27. Extracted and non-extracted shares of water under scenarios A and B (summer – October to March inclusive).............50 Table 28. Comparison of allocated and extracted water under Scenario D schemes .......................................................................52 Table 29. Indicators of use during dry periods under Scenario D schemes ......................................................................................56 Table 30. Comparison of inflows from catchment runoff under Scenario D relative to Scenario C ...................................................57 Table 31. Percent time end-of-system flow for catchments is greater than 1 ML under Scenario D relative to Scenario C .............57 Table 32. Comparison of current extractions for catchments under Scenario D relative to Scenario C............................................58 Table 33. Comparison of change in peak flows for catchments under Scenario D relative to Scenario C........................................64

Figures

Figure 1. Project extent and reporting regions.....................................................................................................................................1 Figure 2. Land cover, major rivers and towns in the Pipers-Ringarooma region.................................................................................2 Figure 3. Modelled catchments, major storages and reporting locations in the Pipers-Ringarooma region........................................3 Figure 4. Subcatchment delineation and WIMS licence locations .......................................................................................................7 Figure 5. Irrigation developments and increase in forest cover due to future commercial forest plantations in the Pipers-Ringarooma region ...................................................................................................................................................................9 Figure 6. River transects showing streamflow under scenarios P, A and C ......................................................................................18 Figure 7. End-of-system (EOS) streamflow in the Pipers-Ringarooma region under (a) Scenario A, and difference from Scenario A under scenarios (b) Cwet, (c) Cmid and (d) Cdry ..............................................................................................................................20 Figure 8. Storage behaviour over representative ten-year period under scenarios A and C.............................................................21 Figure 9. Total annual extractions for the Pipers-Ringarooma region under (a) Scenario A, and difference from Scenario A under scenarios (b) Cwet, (c) Cmid and (d) Cdry ........................................................................................................................................22 Figure 10. Allocation and extraction reliability for catchments under scenarios A and C (annual) ....................................................27 Figure 11. Allocation and extraction reliability for catchments under scenarios A and C (summer – October to March inclusive) ...30 Figure 12. Mean monthly end-of-system flow and daily flow duration curves under scenarios P, A and C ......................................34 Figure 13. Extracted and non-extracted shares of water for the Pipers-Ringarooma region under scenarios A and C (annual)......40 Figure 14. Extracted and non-extracted shares of water for catchments under scenarios A and C (annual) ...................................41 Figure 15. Mean end-of-system monthly flow and daily flow duration curves for catchments under scenarios A and B ..................45 Figure 16. Mean annual extracted and non-extracted shares of water for the Pipers-Ringarooma region under scenarios A and B...........................................................................................................................................................................................................47 Figure 17. Allocation and extraction reliability under Scenario D schemes .......................................................................................53 Figure 18. Mean monthly end-of-system flow under scenarios P, A, and C; and changes under Scenario D relative to Scenario C...........................................................................................................................................................................................................61

© CSIRO 2009 River modelling for Tasmania. Volume 3: the Pipers-Ringarooma region ▪ 1

1 Introduction

This report is one in a series of technical reports from the CSIRO Tasmania Sustainable Yields Project. The terms of

reference for the project require an assessment of the current and likely future extent and variability of surface and

groundwater resources in Tasmania. This information will help governments, industry and communities consider the

environmental, social and economic aspects of the sustainable use and management of the precious water assets of

Tasmania.

The purpose of this report is to describe in detail the river system modelling undertaken for the project. The main

objective of the river system modelling is to estimate flows in river systems across Tasmania for four scenarios using a

consistent Tasmania-wide modelling approach, recognising that the natural and managed behaviour of rivers means that

variability in runoff is not uniformly translated to variability in river flows and water uses. The four scenarios are:

Scenario A – historical climate (1 January 1924 to 31 December 2007) and current development

Scenario B – recent climate (data from 1 January 1997 to 31 December 2007 were concatenated to make an

84-year sequence) and current development

Scenario C – future climate (~2030) and current development (84-year sequence scaled for ~2030 conditions)

Scenario D – future climate (~2030) and future development (84-year sequence scaled for ~2030 conditions).

These were compared with a fifth scenario, Scenario P, which represents water availability modelled with historical

climate, current infrastructure and no extractions. This allows the impact of extractions to be explicitly considered.

The results of the climate and runoff modelling are key inputs to the river system modelling. The climate and runoff

modelling are described in reports by Post et al. (2009) and Viney et al. (2009) respectively.

This report describes the river system modelling and results for the Pipers-Ringarooma region. The river system

modelling method is described in Section 2. The key modelling results for each scenario are presented in sections 3 to 5.

This report is part of a series of reports describing river system modelling for each of the five regions, namely the

Arthur-Inglis-Cam, Mersey-Forth, Pipers-Ringarooma, South Esk and Derwent-South East regions (Ling et al., 2009a–e).

The reporting regions are shown in Figure 1. The project provides only limited reporting on sustainable yields for parts of

the west coast and south-west and for the smaller offshore islands. Figure 2 illustrates the location of the major towns

and main land uses in the region. A map of the reporting locations in the Pipers-Ringarooma region is shown in Figure 3.

Figure 1. Project extent and reporting regions

2 ▪ River modelling for Tasmania. Volume 3: the Pipers-Ringarooma region © CSIRO 2009

Figure 2. Land cover, major rivers and towns in the Pipers-Ringarooma region


Figure 3. Modelled catchments, major storages and reporting locations in the Pipers-Ringarooma region


Table 1. Catchments in the Pipers-Ringarooma region

Number Catchment Area Mean annual rainfall

Mean annual runoff

Mean annual extraction

km2 mm/y GL/y GL/y

02 Musselroe-Ansons 921 879 211.6 7.9

03 George 518 1044 260.1 1.5

04 Scamander-Douglas 660 908 190.0 1.6

42 North Esk 1061 1057 461.3 19.7

44 Pipers 715 882 179.7 3.1

45 Little Forester 350 1081 124.7 3.5

46 Great Forester-Brid 772 982 256.0 24.0

47 Boobyalla-Tomahawk 633 812 116.8 5.9

48 Ringarooma 955 1190 464.5 11.7

For modelling purposes, the Pipers-Ringarooma region was divided into 9 catchments (see Table 1). A large proportion

of the end-of-system flow comes from the North Esk and Ringarooma catchments, which are the largest catchments by

area. Rainfall varies across the region from a mean of 812 mm/year over the Boobyalla-Tomahawk catchment to

1190 mm/year over the Ringarooma catchment.

The Pipers-Ringarooma region includes three large storages which were modelled as part of the river system: Curries

River Reservoir in the Pipers catchment, and Cascade Dam and Frome Dam in the Ringarooma catchment. See Table 2

for details of these storages. The releases represent controlled releases only and not spill from the storages. The degree

of regulation is calculated by dividing the mean annual releases by the mean annual inflow.

Table 2. Large storages in the Pipers-Ringarooma region

Effective storage

Mean annual inflow

Mean annual

releases

Degree of regulation

GL GL/y

Major irrigation supply reservoirs

Cascade Dam 3.25 24.26 5.75 0.24

Curries River Reservoir 11.50 3.30 0.74 0.22

Frome Dam 1.96 19.17 16.99 0.89

Region total 16.71 46.73 23.48 0.50


2 Methods

This section is a summary of the generic approach used for river system modelling and a brief description of the

9 catchment models in the Pipers-Ringarooma region.

River system models describing current infrastructure, water demands and water management rules were used to

assess the implications of changed inflows for water availability and the reliability of water supply to users. Most of the

river system models are based on the TasCatch models developed for Department of Primary Industries, Parks, Water

and Environment (DPIPWE) (Willis, 2008). These models were funded by the Australian Government Water Fund, for the

Water Smart Australia Project, Better Information for Better Outcomes Enhancing Water Planning in Tasmania and the

Tasmanian Government SMART Farming budget initiative. New models were developed for the catchments which were

not covered by existing DPIPWE models.

TasCatch models are node-link network models developed in Hydstra (Kisters, 2009) which include a water balance

model, streamflow routing, water allocations and extractions, and environmental flows. For the purposes of this project,

the water balance and streamflow lag and attenuation were removed from the models. This is because gridded runoff,

rainfall and evaporation were provided as inputs to the models (Viney et al., 2009). The lag and attenuation of streamflow

was therefore removed as the calibration technique used to produce the input runoff grid implicitly included routing. The

models run on a daily time step and route the runoff through the river system. The runoff in each subcatchment was

calculated as the mean of the gridded runoff over the subcatchment. Runoff from each grid cell was weighted in the

averaging process depending on the proportion of the grid cell that fell within a subcatchment. Subcatchment runoff was

then routed through the river network to the next subcatchment downstream. In areas where a number of catchment

models flow into one another in series, the models were run in logical sequence so that the outflow from the upstream

model was an input to the downstream model. Running of the models was automated so that all catchment models were

run in logical order for each scenario.

Rainfall and evaporation grids were used to calculate the rainfall and evaporation occurring over the surface area of

storages within the models.

Model subcatchment delineation and definition of the river network was initially performed using CatchmentSIM GIS

software (Catchment Simulation Solutions, 2009). Within a given catchment, subcatchments were defined to be of similar

size and to ensure that the routing length between catchment centroids was representative of the river length.

Subcatchments were broken upstream of river junctions. The outputs were visually checked to ensure accurate

representation of the catchment, and modifications were made manually as required. The subcatchment delineation is

shown in Figure 4.

2.1 Allocations and extractions

2.1.1 Water entitlements

Information on the current water entitlements as of December 2008 was obtained from DPIPWE’s Water Information

Management System (WIMS) database. WIMS includes an annual allocation and period for each licence. For example, a

licence may be for 200 ML from October to February. Each licence in the catchment is of a given surety (from 1 to 8),

with surety 1 to 4 representing high priority extractions for modelling purposes and surety 5 to 8 representing low priority.

Details of surety levels are given in Table 3 and the location of the WIMS licences are shown in Figure 4.


Table 3. Department of Primary Industries, Parks, Water and Environment surety descriptions (from DPIPWE, 2009)

Surety Description

High priority

1 Rights for the taking of water for domestic purposes, consumption by livestock or firefighting under Part 5 of the Water Management Act 1999 and rights of councils to take water under Part 6 of the Act. Surety 1 water is expected to be available at about 95 percent reliability.

2 The water provision allocated to supply the needs of ecosystems dependent on the water resource.

3 Rights of licensees granted a water licence as a replacement of the ‘prescriptive rights’ (‘pre-Hydro Tasmania rights’) granted under the previous Water Act 1957.

4 Rights of special licensees such as Hydro Tasmania.

Low priority

5 Rights issued for the taking of water otherwise than for the purposes described above under surety levels 1 to 4. This includes rights issued for the taking of water under Part 6 of the Act for direct extraction, and for winter storage in dams, for use for irrigation or other commercial purposes. Surety 5 water is expected to be available at about 80 percent reliability.

6 Rights at this surety level issued for the taking of water under Part 6 of the Act for direct extraction for use for irrigation and other commercial purposes and for winter storage in dams. Surety 6 water is expected to be available at less than 80 percent reliability.

7, 8 Water allocations available with a lower level of reliability than a surety 6 allocation.

There is no record of actual extraction amounts over the year because extractions are currently not metered. In the

absence of any information on the monthly profile of irrigation extractions, allocation was assumed to be evenly extracted

over the allocation period, resulting in a constant daily allocation over the allocation period. Allocations were accumulated

in each subcatchment, and daily extraction of the allocated amount was attempted, based on surety priority. Where

sufficient water is not available for the full allocation, the extracted amount equalled the amount available.

2.1.2 Unlicensed storages

In Tasmania, a water licence is not required for storages of less than 1 ML. Numbers of unlicensed storages were

estimated by visually identifying small dams not included in the WIMS database as extractions in selected catchments.

These results were then extrapolated to other similar catchments. Where unlicensed storages had been estimated for a

catchment in the TasCatch modelling process, these figures were used (Willis, 2008). For the remaining areas, a

combination of dam counting and extrapolation of unlicensed storages in neighbouring catchments was used. Dams

were manually counted in all calibration catchment areas (details of calibration catchments can be found in Viney et al.

(2009)).


Figure 4. Subcatchment delineation and WIMS licence locations

2.1.3 Unlicensed extractions

It is assumed that there will be some unlicensed extractions. The volume of unlicensed extractions for each catchment

was estimated based on local advice provided by DPIPWE.

2.1.4 Environmental flows and releases

In addition to the restriction thresholds shown in Table 4, a minimum flow of 2.0 ML/day is released from Cascade Dam

into the Cascade River. Environmental flow rules were included in models where they are included in water management

plans. Environmental flow studies have been completed at a number of locations in the region which are not yet

mandated via a water management plan.

2.1.5 Diversions, storages and model customisation

A number of catchments include water diversion infrastructure or specific rules which control extractions. This includes

rivers where a ‘cease-to-take’ flow rule is in place, meaning that extractions from the river must be ceased when flow in

the river at a specified location falls below a set minimum (or threshold). Flow rules are set in stages, with stage 1 as the

first rule to be enforced, followed by stage 2 rules, followed by the rules for other stages. In catchments where a flow rule


is in place, the models required custom coding to account for associated operating rules, and these were treated as a

reduction in allocation. Restriction rules for catchments in the Pipers-Ringarooma region are shown in Table 4.

Table 4. Extraction restriction rules

River Location Catchment Month Threshold Stage Restriction rule

ML/d

24 1 Ban on 50% surety 5 and all surety 6 direct takesBrid Upstream tidal limit Great Forester-Brid

All year

20 2 Ban on all surety 5 direct takes

17 1 Ban on 50% surety 5 direct takes

10 2 Ban on all surety 5 direct takes after 5 days below threshold

North Esk Chimney Saddle North Esk All year

10 3 Ban on all surety 4 takes



St Patricks Nunamara North Esk All year

10 3 Ban on all surety 4 takes after 5 days below threshold

6 1 Ban on all surety 6 direct takes Pipers Downstream Yarrow Creek

Pipers All year



43 2 Ban on all surety 6 direct takes after 3 days below threshold

Ringarooma Moorina Ringarooma All year

43 3 Ban on 50% surety 5 direct takes after 3 days below threshold



Little Forester Golconda Rd Little Forester All year





Great Forester 2 km upstream Forester Road

Great Forester-Brid

All year


Generic model functions representing storage and restriction rules were coded for use in the models. The values specific

to the catchment conditions were passed to these functions during the running of the model. The Ringarooma model

required the most customisation in this region. The customisations of this model are briefly described below. A more

detailed description of the models can be found in Willis et al. (2009).

Ringarooma Model

Upper Wyniford Diversion

The majority of the flow of the upper Wyniford River is diverted into the Frome River catchment, where it is eventually

used for the generation of hydro-electricity by the privately-owned Moorina Hydro Power Station. The Moorina Hydro

Power Company, which operates the diversion and power station, has a licence to divert flows of up to 35 ML/day from

the upper Wyniford River. The capacity of the water race to divert water is considerably larger, but modelling assumes

that the license is adhered to. As this water is not consumed, it is eventually returned to the Ringarooma River.

Frome Dam and Hydropower station

Frome Dam, located on the Frome River high in the Ringarooma catchment, is operated as a hydro-electric storage by

the Moorina Hydro Power Company. No information on operating rules for this power station was available when the

model was built. However, a profile of monthly mean releases from the dam was calculated from records of releases

from 2004. This profile is used as a proxy for demand for power generation (and hence demand for water releases). This

is a simple rule of operation, which assumes no change in demand for power or other factors that may lead to releases

being altered.


Cascade Dam

Cascade Dam, located on the Cascade River high in the Ringarooma catchment, is operated to provide water for

irrigation in the Winnaleah Irrigation Scheme over the irrigation season from October to April. Water is piped directly from

Cascade Reservoir to the farms of members of the Winnaleah Irrigation Trust. Annual water-use data was provided by

the Winnaleah Irrigation Trust from 1987 to 2006 (E Shadbolt (Winnaleah Irrigation Trust), 2009, pers. comm.). Mean

water-use over the irrigation season was 5050 ML. Winnaleah Irrigation Trust also supplied intra-season use information

for 2005 to 2008. This information was used to derive a seasonal profile of extractions from the Winnaleah Irrigation

Scheme. There is a minimum environmental release from Cascade Dam of 2 ML/day.

2.2 Future development

2.2.1 Forestry


plantations which will increase total forest cover from 25 percent of the region to 27 percent of the region by 2030. The

increase is spread throughout the region with the largest increases in the north-west (Viney et al., 2009). Future

increases in forestry in the region are shown in Figure 5.

Figure 5. Irrigation developments and increase in forest cover due to future commercial forest plantations in the Pipers-Ringarooma

region


2.2.2 Irrigation

There are ten proposed irrigation dams in the Pipers-Ringarooma region. The details of each dam are shown in Table 5

(S Keppel (Tasmanian Irrigation Development Board), 2009, pers. comm.). All proposed developments are in-stream

dams. The total mean annual demand for all the proposed dams is 47,487 ML/year.

Table 5. Capacity and mean annual demand for proposed irrigation developments for Scenario D

Dam Catchment Capacity Mean annual demand

ML ML/y

St Patricks River North Esk 20,000 17,000

Monarch Mines (Vicarys Creek) Boobyalla-Tomahawk 5,000 2,500

Brid River Great Forester-Brid 3,850 1,925

Great Forester River Great Forester-Brid 8,500 4,250

Oxberry Creek Great Forester-Brid 8,947 4,470

Maryvale (Parr’s Rivulet) Great Forester-Brid 6,500 3,250

Headquarters Road (tributary of Great Forester)

Great Forester-Brid 1,980 1,642

Little Forester Little Forester 5,500 2,750

Tomahawk River Boobyalla-Tomahawk 11,500 8,000

Great Musselroe River Musselroe 53,000 17,000

IQQM software was used for each dam to derive a crop demand which projected a daily extraction profile (ML/day). This

was then used in the relevant catchment model as a consumptive extraction taken directly from the proposed dam. The

daily demand was determined using the SILO gridded rainfall and evaporation over the irrigation area, an adopted soil

moisture parameter and summer grasses as the crop type. The model was run over the 84-year period, and the irrigable

area was adjusted until the annual mean demand was equal to the proposed annual mean extraction. For each year, the

irrigation volume required to water this irrigable area was then determined. This varied year to year depending on the

rainfall and evaporation. This process produced a daily extraction series which maintained the mean annual demand

whilst varying the required amount year to year to reflect actual demand. This extraction series was used as the

Scenario D extraction taken directly from the proposed dam. This extraction series was used as the Scenario D

extraction taken directly from the proposed dam.

The procedure was run for scenarios Dwet, Dmid and Ddry. The resulting irrigable areas for each proposed dam

development are shown in Table 6.

Table 6. Irrigable area for proposed irrigation developments for Scenario D

Dam Mean annual demand

Irrigable area

Dwet Dmid Ddry

ML/y ha

St Patricks River 17,000 7,010 6,678 6,574

Monarch Mines (Vicarys Creek) 2,500 783 764 749

Brid River 1,925 726 692 683

Great Forester River 4,250 1,345 1,285 1,284

Oxberry Creek 4,470 1,375 1,315 1,315

Maryvale (Parr’s Rivulet) 3,250 1,082 1,033 1,032

Headquarters Road 1,642 584 557 556

Little Forester 2,750 896 864 825

Tomahawk River 8,000 2,493 2,432 2,387

Great Musselroe River 17,000 5,407 5,273 5,169


Environmental flow studies have been undertaken in many of the rivers on which developments are proposed; however,

recommendations for environmental flow regimes at the dam sites are not available except for Headquarters Road Dam.

In the absence of environmental flow studies, an estimate of environmental releases was made for inclusion in the

modelling. In the model, environmental release requirements were given priority over irrigation demand. In the absence

of environmental flow studies, the environmental releases are based on a default 20th percentile of long-term winter flows

and 30th percentile of long-term summer flows, calculated as a monthly release profile. When the inflow to the storage is

less than the monthly environmental release profile, the downstream release is reduced to the inflow to the storage.

A one- and two-year flood flow was derived using a Log-Pearson Type III partial series flood frequency analysis of the

modelled inflow data. These flood flows were released from the storage annually (one-year return period flood) and

biennially (two-year return period flood), when not met by natural flows.

These environmental releases are only an estimate of the likely environmental requirements in the absence of other

information.

For the Headquarters Road Dam the environmental flows used in the model were adopted from those in the

environmental flows report (Freshwater Systems 2004).

The reliability of the schemes in the Great Forester-Brid catchment will be impacted by proposed dams upstream. The

reliability of downstream schemes should be re-evaluated if the proposed upstream schemes change.


3 Under historical climate (Scenario A) and future

climate (Scenario C)

This section reports on hydrology under Scenario A and on hydrology under Scenario C relative to Scenario A. Three

scenarios are presented for Scenario C: wet extreme (Scenario Cwet), median (Scenario Cmid) and dry extreme

(Scenario Cdry). The selection of these scenarios was based on projected changes in mean annual runoff from the

14 km resolution pattern-scaled projections of the 15 global climate models (GCMs). The selection of climate scenarios is

described in detail by Viney et al. (2009). In summary, the wettest of the three global warming projections from the

second wettest GCM (CNRM) was chosen as Scenario Cwet. The projection representing 1.0 degree global warming

from the eighth wettest GCM (CCCMA T63) was chosen as Scenario Cmid. The driest of the three global warming

projections from the second driest GCM (GFDL) was chosen as Scenario Cdry. This selection of scenarios Cwet, Cmid

and Cdry was performed separately for each region. As the selection of these scenarios was based on mean annual

runoff over the region, they can vary in order on the basis of season and catchment.

Statistics reported for ‘summer’ or ‘winter’ refer to October to March and April to September respectively.

3.1 Water balance and water availability

The mass balance table (Table 7a–i) shows the net fluxes for each catchment in the Pipers-Ringarooma region. Fluxes

under Scenario A are presented as GL/year, while fluxes under all other scenarios are presented as a percentage

change relative to Scenario A.

The storage volumes refer to the major lakes within the region. The inflows are separated into flows from catchment

runoff, and flows from hydro-electric schemes. The catchment losses include any water transfers (diversions) into or out

of the catchment, and evaporation from major storages. Extractions are shown based on surety level. The catchment

losses are positive for a net loss for the catchment and negative for a net gain (for example the loss will be negative if

rainfall over a storage surface exceeds evaporation, or water is transferred into a catchment). The net catchment

trasfers/losses represent direct extractions from Curries Dam in the Pipers catchment and Cascade storage and Frome

Dam in the Ringarooma catchment.

Table 7 shows that mean annual catchment runoff decreases under Scenario Cwet relative to Scenario A in seven of the

nine catchments, and decreases under scenarios Cmid and Cdry relative to Scenario A in all catchments. The maximum

decrease in mean annual catchment runoff under Scenario Cdry relative to Scenario A is 16 percent in the North Esk

catchment. Net evaporation from Curries Dam storage in Pipers catchment is projected to increase by 36 percent under

Scenario Cdry. Net evaporation from the Frome and Cascade dams in the Ringarooma catchment decreases by

50 percent under Scenario Cdry.

The mean annual extraction amounts decrease slightly or remain the same under Scenario Cwet relative to Scenario A

in all catchments except Musselroe-Ansons where the unlicensed extraction increases. Mean annual extractions

decrease under scenarios Cmid and Cdry relative to Scenario A by up to 10 percent in the Great Forester-Brid

catchment. These changes are mainly in surety 5 and 6 extractions due to extraction restriction rules which ban surety 5

and 6 extractions when flows drop below a given threshold (Table 4).

End-of-system (EOS) flows decrease in all catchments under scenarios Cmid and Cdry relative to Scenario A. The

decrease under Scenario Cdry is up to 17 percent in the North Esk catchment.


Table 7. Mean annual water balance for each catchment under scenarios A and C

(a) 02_Musselroe-Ansons

A Cwet Cmid Cdry

GL/y percent change relative to Scenario A

Storage volume

Mean annual change in volume na na na na

Inflows

From catchment runoff 211.6 1% -4% -11%

From flows downstream of hydro schemes na na na na

Total (inflows) 211.6 1% -4% -11%

Outflows

Net catchment transfers/losses (including storages if any)

na na na na

Net evaporation (evaporation - rainfall) from storages na na na na

Sub-total (net transfer and net evaporation) na na na na

Extractions

Surety 1 0.0 na na na




Surety 5 4.6 0% -1% -3%

Surety 6 0.1 0% 0% 0%



Unlicensed 3.2 1% -1% -5%

Sub-total (extractions) 7.9 1% -1% -4%

End-of-system (EOS) streamflow 203.7 1% -4% -12%

Total (outflows) 211.6 1% -4% -11%na – not applicable

(b) 03_George

A Cwet Cmid Cdry


Storage volume


Inflows

From catchment runoff 260.1 -4% -8% -13%


Total (inflows) 260.1 -4% -8% -13%

Outflows


na na na na



Extractions

Surety 1 0.0 0% 0% 0%




Surety 5 0.7 0% 0% 0%

Surety 6 0.1 -1% -3% -6%



Unlicensed 0.7 0% 0% -1%

Sub-total (extractions) 1.5 0% 0% -1%

End-of-system (EOS) streamflow 258.6 -4% -8% -13%

Total (outflows) 260.1 -4% -8% -13%na – not applicable


Table 7. Mean annual water balance for each catchment under scenarios A and C (continued)

(c) 04_Scamander-Douglas

A Cwet Cmid Cdry


Storage volume


Inflows



Total (inflows) 190.0 -3% -8% -15%

Outflows


na na na na



Extractions

Surety 1 0.0 0% 0% 0%




Surety 5 0.7 -2% -3% -5%




Unlicensed 0.8 -1% -2% -4%

Sub-total (extractions) 1.6 -2% -3% -5%



(d) 42_North Esk

A Cwet Cmid Cdry


Storage volume


Inflows



Total (inflows) 461.3 -6% -10% -16%

Outflows


na na na na



Extractions

Surety 1 11.5 0% 0% 0%



Surety 4 5.6 0% -1% -1%

Surety 5 1.6 -1% -2% -3%

Surety 6 0.1 -1% -3% -5%



Unlicensed 0.8 0% 0% 0%

Sub-total (extractions) 19.7 0% 0% -1%





(e) 44_Pipers

A Cwet Cmid Cdry


Storage volume

Mean annual change in volume 0.0 -52% -123% -171%

Inflows



Total (inflows) 179.7 -2% -7% -13%

Outflows


0.7 0% 0% 0%

Net evaporation (evaporation - rainfall) from storages – Curries Dam Reservoir

0.5 8% 27% 37%

Sub-total (net transfer and net evaporation) 1.2 3% 10% 14%

Extractions

Surety 1 0.2 -1% -1% -2%




Surety 5 1.3 -1% -1% -2%




Unlicensed 1.6 -1% -3% -4%




(f) 45_Little Forester

A Cwet Cmid Cdry


Storage volume


Inflows



Total (inflows) 124.7 -4% -9% -15%

Outflows


na na na na



Extractions

Surety 1 0.0 0% 0% 0%




Surety 5 3.0 0% 0% 0%

Surety 6 0.1 0% -1% -2%




Sub-total (extractions) 3.5 0% 0% 0%





(g) 46_Great Forester-Brid

A Cwet Cmid Cdry


Storage volume


Inflows



Total (inflows) 256.0 -3% -8% -14%

Outflows


na na na na



Extractions

Surety 1 0.9 -1% -2% -3%


Surety 3 0.2 0% 0% 0%


Surety 5 8.9 -2% -3% -5%

Surety 6 13.2 -4% -9% -16%







(h) 47_Boobyalla-Tomahawk

A Cwet Cmid Cdry


Storage volume


Inflows

From catchment runoff 116.8 3% -3% -11%


Total (inflows) 116.8 3% -3% -11%

Outflows


na na na na



Extractions

Surety 1 0.1 0% 0% 0%




Surety 5 5.2 -1% -2% -3%

Surety 6 0.0 0% 0% 0%





End-of-system (EOS) streamflow 110.9 3% -4% -11%

Total (outflows) 116.8 3% -3% -11%na – not applicable



(i) 48_Ringarooma

A Cwet Cmid Cdry

percent change relative to Scenario A

Storage volume

Mean annual change in volume 0.0 -262% -487% -731%

Inflows



Total (inflows) 464.5 -4% -9% -14%

Outflows


5.0 0% -1% -2%

Net evaporation (evaporation - rainfall) from storages – Cascade + Frome

-0.2 18% 33% 50%

Sub-total (net transfer and net evaporation) 4.8 0% 1% 1%

Extractions

Surety 1 1.2 0% 0% 0%




Surety 5 8.3 -1% -1% -3%

Surety 6 1.5 -1% -1% -2%







Figure 6 shows the mean annual streamflow for the major river reaches in each catchment under scenarios P, A and C

where C range is defined by the upper and lower bounds of Scenario C streamflow. Generally this is defined by

streamflow under scenarios Cwet and Cdry, but due to the way that the C scenarios are derived, occasionally

Scenario Cmid may be used. All of the major rivers in the region are gaining reaches (where the flow in the river

increases moving downstream). Up to a maximum of eight reporting locations were included for each major river reach.

The number of reporting locations on a river is related to the number of modelled subcatchments on the river. In some

catchments, there are less than eight reporting locations, as the largest river reach in the catchment is modelled by less

than eight subcatchments. EOS represents the total flow at the end of the catchment. In catchments where there is a

major river and a number of smaller rivers, the EOS flow is the summation of the end-of-river flow for all rivers within the

catchment.

The reporting locations are shown in Figure 3. The differences in the flows for Scenario P relative to Scenario A show the

impact of extractions from the river.

On all the major rivers, river flows decrease or remain the same under Scenario C relative to Scenario A.


(a) 02_Musselroe-Ansons (Great Musselroe River)

0

50

100

150

200

250

1 2 3 4 5 6 7 8 EOSReporting location

Mea

n an

nual

flow

(G

L) . C range

Cmid

A

P

(b) 03_George (George River)

0

50

100

150

200

250

300

1 2 3 4 5 EOSReporting location

Mea

n an

nual

flow

(G

L)

C range

Cmid

A

P

(c) 04_Scamander-Douglas (Scamander River)

0

50

100

150

200

1 2 3 4 5 6 7 EOSReporting location

Mea

n an

nual

flow

(G

L) C range

Cmid

A

P

(d) 42_North Esk (North Esk River)

0

100

200

300

400

500


Mea

n an

nual

flow

(G

L) . C range

Cmid

A

P

Figure 6. River transects showing streamflow under scenarios P, A and C


0

50

100

150

200

250

300


Mea

n an

nual

flow

(G

L) . C range

Cmid

A

P

(e) 44_Pipers (Pipers River)

0

50

100

150

200


Mea

n an

nual

flow

(G

L) . C range

Cmid

A

P

(f) 45_Little Forester (Little Forester River)

0

20

40

60

80

100

120

140

1 2 3 4 5 6 7 EOSReporting location

Mea

n an

nual

flow

(G

L) C range

Cmid

A

P

(g) 46_Great Forester-Brid (Great Forester River)

(h) 47_Boobyalla-Tomahawk (Tomahawk River)

0

20

40

60

80

100

120

140

1 2 3 4 5 6 EOSReporting location

Mea

n an

nual

flow

(G

L) C range

Cmid

A

P

Figure 6. River transects showing streamflow under scenarios P, A and C (continued)


(i) 48_Ringarooma (Ringarooma River)

0

100

200

300

400

500


Mea

n an

nual

flow

(G

L) . C range

Cmid

A

P

Figure 6. River transects showing streamflow under scenarios P, A and C (continued)

A time series of annual water availability for the whole Pipers-Ringarooma region, represented as total EOS flow under

Scenario A is shown in Figure 7a. There is a high level of variability in EOS flow between years, ranging from 681 to

4787 GL/year, with a mean of 2180 GL/year. Figure 7b–d shows the difference in annual end-of-system flow under

Scenario C relative to Scenario A. The annual EOS flow decreases in all years under Scenario Cwet relative to

Scenario A, by up to 136 GL/year, with a mean of 70 GL/year. The annual EOS flow under Scenario Cmid decreases in

all years relative to Scenario A, and ranges from a decrease of 82 GL/year to 311 GL/year, with a mean decrease of

178 GL/year. Annual EOS flow decreases under Scenario Cdry relative to Scenario A ranging from 126 to 529 GL/year

with a mean of 312 GL/year.

(a) Scenario A (b) Scenario Cwet

0

1000

2000

3000

4000

5000

0 20 40 60 80

Year

Ann

ual E

OS

vol

ume

(GL)

.

-600

-500

-400

-300

-200

-100

0

0 20 40 60 80Year

Ann

ual d

iffer

ence

(G

L)

(c) Scenario Cmid (d) Scenario Cdry

-600

-500

-400

-300

-200

-100

0

0 20 40 60 80

Year

Ann

ual d

iffer

ence

(G

L) .

-600

-500

-400

-300

-200

-100

0

0 20 40 60 80

Year

Ann

ual d

iffer

ence

(G

L)

Figure 7. End-of-system (EOS) streamflow in the Pipers-Ringarooma region under (a) Scenario A, and difference from Scenario A under

scenarios (b) Cwet, (c) Cmid and (d) Cdry


3.2 Storage behaviour

The modelled behaviour of storages gives an indication of the level of regulation of a system, as well as how reliable the

storage is during extended periods of low inflows. Table 8 details the behaviour of the major lakes in the region under

scenarios A and C for the full 84-year run. All the storages spill regularly over the 84 years. The mean and maximum

days between spills increase under scenarios Cmid and Cdry relative to Scenario A. Time series of storage volume for a

representative ten years are shown in Figure 8. These time series represent the modelled storage behaviour which

included 2007 operating rules. The storage behaviour therefore is not necessarily representative of historical storage

levels. The storages are generally drawn down to lower volumes under Scenario C relative to Scenario A; however,

these differences are minor. Frome and Cascade dams are regularly drawn down to minimum volume during the

84 years under all scenarios.

(a) Cascade Dam (b) Curries Dam Reservoir

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

15 16 17 18 19 20 21 22 23 24Year

Vol

ume

(GL)

.

C rangeCmidA

0

2

4

6

8

10

12

14

15 16 17 18 19 20 21 22 23 24Year

Vol

ume

(GL)

.C rangeCmidA

(c) Frome Dam

0.0

0.5

1.0

1.5

2.0

2.5

15 16 17 18 19 20 21 22 23 24Year

Vol

ume

(GL)

.

C range A Cmid

Figure 8. Storage behaviour over representative ten-year period under scenarios A and C

Table 8. Storage behaviour under scenarios A and C

A Cwet Cmid Cdry

Cascade Dam

Minimum storage volume (GL) 0 0 0 0

Mean days between spills 67 76 81 93

Maximum days between spills 258 298 305 311

Curries Dam Reservoir




Frome Dam





3.3 Consumptive water use

Consumptive water use includes both the licensed and unlicensed extractions from the river system. The modelling of

extractions is described in Section 2.1.1. Time series of annual extractions under Scenario A are shown in Figure 9a.

Total annual extractions for the region vary from a minimum of 65 to a maximum of 90 GL/year over the 84 years with a

mean of 79 GL/year. The differences in annual extractions under Scenario C are shown in Figure 9b–d. Extractions are

lower in every year under scenarios Cwet, Cmid and Cdry relative to Scenario A. The mean annual decrease in

extractions under scenarios Cwet, Cmid and Cdry relative to Scenario A are 0.9, 1.9 and 3.6 GL/year respectively. These

reductions are relatively small in comparison to the mean annual extraction of 79 GL/year under Scenario A (1.1, 2.4 and

4.6 percent respectively). The changes in extraction volumes are largely in surety 5 and 6 extractions.

(a) Scenario A (b) Scenario Cwet

0

20

40

60

80

100

0 20 40 60 80Year

Ann

ual e

xtra

ctio

n vo

lum

e .

(GL)

.

-6

-5

-4

-3

-2

-1

0

0 20 40 60 80Year

Ann

ual d

iffer

ence

(G

L) .

(c) Scenario Cmid (d) Scenario Cdry

-6

-5

-4

-3

-2

-1

0

0 20 40 60 80

Year

Ann

ual d

iffer

ence

(G

L) .

-6

-5

-4

-3

-2

-1

0

0 20 40 60 80

Year

Ann

ual d

iffer

ence

(G

L) .

Figure 9. Total annual extractions for the Pipers-Ringarooma region under (a) Scenario A, and difference from Scenario A under

scenarios (b) Cwet, (c) Cmid and (d) Cdry


Table 9 shows the mean annual volume of allocated and extracted water in each catchment in the region under

scenarios A and C. The mean annual extracted volumes are less than the mean annual allocation in all catchments

except the Little Forester under all scenarios. The mean annual extracted volume does not change significantly under

Scenario C relative to Scenario A. Based on the differences between the allocated and extracted volume annual means

from the river modelling, the river systems are unable to supply the full allocation for extraction. In the absence of any

information on actual extractions from rivers, the river models assume that each water licence’s full allocation is divided

evenly over the applicable months. In reality, irrigators may have offstream storages that can be used to store water

when there is less water in the river system, and thus will extract water from the river when it is available. The methods

used in the river modelling may therefore result in a lower volume of water being extracted in the model relative to the

actual situation. In the Musselroe-Ansons catchment, a number of relatively large storages on tributaries of the

Musselroe River represent the majority of the allocated volume. The WIMS includes the full volume of the storage as the

annual licensed allocation, and this volume was used as the allocation in the river system modelling. The low volume of

extraction relative to the allocated volume results from the operation of the river system models to attempt to supply this

full volume each year.

Table 9. Allocated and extracted mean annual flows for catchments under scenarios A and C

A Cwet Cmid Cdry

GL/y

02_Musselroe-Ansons

Allocated water 15.8 15.8 15.8 15.8

Extraction 7.9 8.0 7.8 7.6

Difference 7.9 7.8 8.0 8.2

03_George


Extraction 1.5 1.5 1.5 1.5

Difference 0.1 0.1 0.1 0.1

04_Scamader-Douglas


Extraction 1.6 1.5 1.5 1.5

Difference 0.7 0.7 0.7 0.8

42_North Esk


Extraction 19.7 19.6 19.6 19.5

Difference 0.1 0.1 0.1 0.2

44_Pipers


Extraction 3.1 3.0 3.0 3.0

Difference 0.2 0.3 0.3 0.3

45_Little Forester


Extraction 3.5 3.5 3.5 3.5

Difference 0.0 0.0 0.0 0.0

46_Great Forester-Brid


Extraction 24.0 23.3 22.6 21.5

Difference 2.9 2.9 3.1 3.2

47_Boobyalla-Tomahawk


Extraction 5.9 5.9 5.8 5.7

Difference 1.4 1.5 1.5 1.6

48_Ringarooma


Extraction 11.7 11.6 11.5 11.4

Difference 0.1 0.1 0.1 0.1


The mean annual reliability of high and low priority extractions is shown in Table 10 for each catchment as fraction

extracted per unit of water allocated. The reliabilities of extractions over summer and winter are shown in Table 11 and

Table 12 respectively. The annual reliability of high priority extractions under Scenario A ranges from 87 percent in the

Pipers catchment to 100 percent in all other catchments. The reliability of low priority extractions in the

Musselroe-Ansons is very low with a mean of 50 percent under Scenario A. In summer, the reliability of both high and

low priority extractions is slightly lower than the reliability of annual extractions in most catchments, reflecting the lower

water availability in this region in summer. The low reliability of low priority extractions in the Musselroe-Ansons

catchment is exaggerated by the assumption that allocations were attempted to be taken at a constant rate throughout

the license period as previously discussed.

The reliability of annual extractions changes by less than 4 percent in all catchments for both high and low priority

extractions under Scenario C relative to Scenario A on an annual and seasonal basis.

Table 10. Mean reliability of high and low priority allocations for catchments under scenarios A and C (annual)

A Cwet Cmid Cdry

fraction extracted per unit allocated

02_Musselroe-Ansons

High priority (surety 1 to 4) - - - -

Low priority (surety 5 to 8 & unlicensed) 0.50 0.51 0.50 0.48

03_George

High priority (surety 1 to 4) 1.00 1.00 1.00 1.00


04_Scamander-Douglas



42_North Esk



44_Pipers



45_Little Forester









48_Ringarooma




Table 11. Mean reliability of high and low priority summer allocations under scenarios A and C (summer – October to March inclusive)

A Cwet Cmid Cdry


02_Musselroe-Ansons



03_George






42_North Esk



44_Pipers



45_Little Forester









48_Ringarooma




Table 12. Mean reliability of high and low priority allocations under scenarios A and C (winter – April to September inclusive)

A Cwet Cmid Cdry


02_Musselroe-Ansons



03_George






42_North Esk



44_Pipers



45_Little Forester









48_Ringarooma



The allocation and extraction reliability as a percentage of years for exceedance of a given volume is shown in Figure 10.

The allocation volume is not constant each year in some catchments due to regulations which restrict allocations under

low flow conditions (see Table 4). Allocation restrictions result in a significant reduction in allocations in many years in the

Great Forester-Brid catchment. The allocation is further reduced in dry years under Scenario C.

Extraction volumes vary significantly over the 84 years, particularly in the Musselroe-Ansons catchment, where the

extraction volume drops to less than 40 percent allocated. There is a slight reduction in extractions under Scenario C

relative to Scenario A in most catchments. Figure 11 shows the same figures for summer only. Summer extractions

generally show more variation over the 84-year sequence than on an annual basis and are less reliable in the driest

years.


(a-1) 02_Musselroe-Ansons – allocated water (a-2) 02_Musselroe-Ansons – extracted per allocated

0

2

4

6

8

10

12

14

16

18

0% 20% 40% 60% 80% 100%Percent of years exceeded

Ann

ual v

olum

e (G

L) .

C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A

(b-1) 03_George – allocated water (b-2) 03_George – extracted per allocated

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8


Ann

ual v

olum

e (G

L) .

C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A

(c-1) 04_Scamander-Douglas – allocated water (c-2) 04_Scamander-Douglas – extracted per allocated

0.0

0.5

1.0

1.5

2.0

2.5


Ann

ual v

olum

e (G

L) .

C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A

(d-1) 42_North Esk – allocated water (d-2) 42_North Esk – extracted per allocated

0

5

10

15

20

25


Ann

ual v

olum

e (G

L) .

C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A

Figure 10. Allocation and extraction reliability for catchments under scenarios A and C (annual)


(e-1) 44_Pipers – allocated water (e-2) 44_Pipers – extracted per allocated

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0


Ann

ual v

olum

e (G

L) .

C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A

(f-1) 45_Little Forester – allocated water (f-2) 45_Little Forester – extracted per allocated

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0


Ann

ual v

olum

e (G

L) .

C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A

(g-1) 46_Great Forester-Brid – allocated water (g-2) 46_Great Forester-Brid – extracted per allocated

0

5

10

15

20

25

30

35


Ann

ual v

olum

e (G

L) .

C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A

(h-1) 47_Boobyalla-Tomahawk – allocated water (h-2) 47_Boobyalla-Tomahawk – extracted per allocated

0

1

2

3

4

5

6

7

8


Ann

ual v

olum

e (G

L) .

C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A

Figure 10. Allocation and extraction reliability for catchments under scenarios A and C (annual) (continued)


(i-1) 48_Ringarooma – allocated water (i-2) 48_Ringarooma – extracted per allocated

0

2

4

6

8

10

12

14


Ann

ual v

olum

e (G

L) .

C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A

Figure 10. Allocation and extraction reliability for catchments under scenarios A and C (annual) (continued)


(a-1) 02_Musselroe-Ansons – allocated water (a-2) 02_Musselroe-Ansons – extracted per allocated

0

2

4

6

8

10

12

14

16

18

0% 20% 40% 60% 80% 100%

Percent of years exceeded

Sum

mer

vol

ume

(GL)

. C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A

(b-1) 03_George – allocated water (b-2) 03_George – extracted per allocated

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

0% 20% 40% 60% 80% 100%


Sum

mer

vol

ume

(GL)

. C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A

(c-1) 04_Scamander-Douglas – allocated water (c-2) 04_Scamander-Douglas – extracted per allocated

0.0

0.5

1.0

1.5

2.0

2.5

0% 20% 40% 60% 80% 100%


Sum

mer

vol

ume

(GL)

.

C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A

(d-1) 42_North Esk – allocated water (d-2) 42_North Esk – extracted per allocated

0

5

10

15

20

25

0% 20% 40% 60% 80% 100%


Sum

mer

vol

ume

(GL)

. C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A

Figure 11. Allocation and extraction reliability for catchments under scenarios A and C (summer – October to March inclusive)


(e-1) 44_Pipers – allocated water (e-2) 44_Pipers – extracted per allocated

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

0% 20% 40% 60% 80% 100%


Sum

mer

vol

ume

(GL)

. C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A

(f-1) 45_Little Forester – allocated water (f-2) 45_Little Forester – extracted per allocated

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

0% 20% 40% 60% 80% 100%


Sum

mer

vol

ume

(GL)

. C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A

(g-1) 46_Great Forester-Brid – allocated water (g-2) 46_Great Forester-Brid – extracted per allocated

0

5

10

15

20

25

30

35

0% 20% 40% 60% 80% 100%


Sum

mer

vol

ume

(GL)

. C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A

(h-1) 47_Boobyalla-Tomahawk – allocated water (h-2) 47_Boobyalla-Tomahawk – extracted per allocated

0

1

2

3

4

5

6

7

8

0% 20% 40% 60% 80% 100%


Sum

mer

vol

ume

(GL)

. C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A


(continued)


(i-1) 48_Ringarooma – allocated water (i-2) 48_Ringarooma – extracted per allocated

0

2

4

6

8

10

12

14

0% 20% 40% 60% 80% 100%


Sum

mer

vol

ume

(GL)

. C rangeCmidA

0.00.10.20.30.40.50.60.70.80.91.0


Ext

ract

ed v

olum

e pe

r

unit

allo

cate

d .

C range

Cmid

A


(continued)

The mean annual volume of extracted water for the lowest one-, three-, and five-year periods under Scenario A, and the

percentage change under Scenario C relative to Scenario A are shown in Table 13. These figures indicate the impact on

water use during dry periods. Extraction volumes generally decrease during dry periods under Scenario Cwet relative to

Scenario A, except in the Musselroe-Ansons and George catchments where they are the same or slightly larger.

Extraction volumes decrease during dry periods under scenarios Cmid and Cdry relative to Scenario A, by up to

16.5 percent for the lowest one-year period of extraction in the Great Forester-Brid under Scenario Cdry. Extraction

volumes show a greater reduction during dry periods under Scenario C relative to Scenario A when compared to

changes in the long-term mean annual extractions, indicating that the volume of water extracted would be reduced by

more in drier periods compared to the long-term mean.


Table 13. Indicators of use during dry periods for catchments under Scenario A and change under Scenario C relative to Scenario A

A Cwet Cmid Cdry


02_Musselroe-Ansons

Lowest 1-year period of extraction 5.6 -0.5% -2.9% -5.2%

Lowest 3-year period of extraction 6.8 0.6% -1.2% -4.0%


Mean annual extraction for 84 years 7.9 0.9% -1.2% -3.8%

03_George




Mean annual extraction for 84 years 1.5 -0.1% -0.3% -0.5%






42_North Esk





44_Pipers





45_Little Forester















48_Ringarooma






3.4 End-of-system river flow

The EOS monthly streamflow and daily flow duration curves for each catchment under scenarios P, A and C are shown

in Figure 12. Scenario P represents current infrastructure with no extractions under historical climate. In all catchments,

the shape of the flow duration curve is consistent under Scenario C compared to Scenario A. The impact of extractions

on low flows is evident under Scenario A relative to Scenario P in most catchments.

The monthly plots show a strong seasonal distribution of flows, with highest flows occurring in the winter months in all

catchments. Mean monthly flows under Scenario C are generally lower than flows under Scenario A in all catchments

except Musselroe-Ansons and Boobyalla-Tomahawk where they are roughly the same.

(a-1) 02_Musselroe-Ansons – monthly flow (a-2) 02_Musselroe-Ansons – daily flow duration

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

J F M A M J J A S O N DMonth

EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

1

10

100

1000

10000

100000

0 20 40 60 80 100Percent time volume is exceeded

EO

S d

aily

flow

(M

L) .

C rangeCmidAP

(b-1) 03_George – monthly flow (b-2) 03_George – daily flow duration

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4


EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

1

10

100

1000

10000

100000


EO

S d

aily

flow

(M

L) .

C rangeCmidAP

(c-1) 04_Scamander-Douglas – monthly flow (c-2) 04_Scamander-Douglas – daily flow duration

0.00.10.20.30.40.50.60.70.80.9


EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

1

10

100

1000

10000

100000


EO

S d

aily

flow

(M

L) .

C rangeCmidAP

Figure 12. Mean monthly end-of-system flow and daily flow duration curves under scenarios P, A and C


(d-1) 42_North Esk – monthly flow (d-2) 42_North Esk – daily flow duration

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5


EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

1

10

100

1000

10000

100000


EO

S d

aily

flow

(M

L) .

C rangeCmidAP

(e-1) 44_Pipers – monthly flow (e-2) 44_Pipers – daily flow duration

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6


EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

1

10

100

1000

10000

100000


EO

S d

aily

flow

(M

L) .

C rangeCmidAP

(f-1) 45_Little Forester – monthly flow (f-2) 45_Little Forester – daily flow duration

0.00.10.20.30.40.50.60.70.80.9


EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

1

10

100

1000

10000

100000


EO

S d

aily

flow

(M

L) .

C rangeCmidAP

(g-1) 46_Great Forester-Brid – monthly flow (g-2) 46_Great Forester-Brid – daily flow duration

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6


EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

1

10

100

1000

10000

100000


EO

S d

aily

flow

(M

L) .

C rangeCmidAP

Figure 12. Mean monthly end-of-system flow and daily flow duration curves under scenarios P, A and C (continued)


(h-1) 47_Boobyalla-Tomahawk – monthly flow (h-2) 47_Boobyalla-Tomahawk – daily flow duration

0.00.10.20.30.40.50.60.70.80.9


EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

1

10

100

1000

10000

100000


EO

S d

aily

flow

(M

L) .

C rangeCmidAP

(i-1) 48_Ringarooma – monthly flow (i-2) 48_Ringarooma – daily flow duration

0.0

0.5

1.0

1.5

2.0

2.5

3.0


EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

1

10

100

1000

10000

100000


EO

S d

aily

flow

(M

L) .

C rangeCmidAP

Figure 12. Mean monthly end-of-system flow and daily flow duration curves under scenarios P, A and C (continued)

EOS daily peak flows for return periods of two, five and ten years are shown in Table 14 under scenarios A and P with

changes under Scenario C relative to Scenario A. Peak flows were determined based on the procedure used in the

Murray-Darling Basin Sustainable Yields Project (CSIRO, 2008), using a partial series analysis and a plotting position

assigned based on rank. Peak flows increase in many catchments for some return periods under Scenario Cwet relative

to Scenario A. The maximum increase in peak flows is 13 percent for the two-year return period in the

Boobyalla-Tomahawk catchment. Peak flows decrease for all return periods in most catchments under Scenario Cdry

relative to Scenario A; however, there is an increase in peak flows for the ten-year return period in the Musselroe-Ansons

and Scamander-Douglas catchments. The maximum reduction in peak flows under Scenario Cdry relative to Scenario A

is 15 percent for the two-year return period flow in the Ringarooma catchment. The selection of scenarios Cwet, Cmid

and Cdry was based on mean annual runoff and peak flows may actually be higher in some years under Scenario Cmid

relative to Scenario Cwet, or Scenario Cdry relative to Scenario Cmid because different GCMs were used to define these

scenarios and these GCMs may scale peak rainfalls by different amounts.


Table 14. Peak flows for catchments under scenarios P and A, and under Scenario C relative to Scenario A

P A Cwet Cmid Cdry

ML/d percent change relative to Scenario A

02_Musselroe-Ansons

2-year 9,087 9,030 1% -3% -8%

5-year 13,241 13,212 6% 0% -5%

10-year 15,464 15,423 4% 3% 3%

03_George

2-year 7,570 7,567 -2% -9% -13%

5-year 12,626 12,623 1% -1% -6%

10-year 16,342 16,336 1% 0% -4%


2-year 16,350 16,346 -3% -6% -12%

5-year 25,167 25,159 2% -1% -12%

10-year 29,446 29,442 0% 5% 2%

42_North Esk

2-year 11,238 11,183 -3% -8% -12%

5-year 14,945 14,890 -2% -5% -10%

10-year 18,343 18,287 -4% -5% -10%

44_Pipers

2-year 7,792 7,775 0% -5% -8%

5-year 10,490 10,473 -2% -3% -8%

10-year 11,818 11,803 2% -3% -8%

45_Little Forester

2-year 3,204 3,190 -3% -8% -13%

5-year 4,175 4,160 -5% -8% -11%

10-year 4,578 4,563 -4% -6% -10%


2-year 4,540 4,494 -3% -6% -12%

5-year 6,377 6,331 -1% -4% -9%

10-year 8,196 8,150 -4% -5% -10%


2-year 3,666 3,639 13% 0% -10%

5-year 6,100 6,069 5% 1% -6%

10-year 7,678 7,647 2% 1% -5%

48_Ringarooma

2-year 9,252 9,221 0% -11% -15%

5-year 12,545 12,330 4% -4% -9%

10-year 16,159 16,128 -7% -9% -11%

The percentage of time end-of-system flow is greater than 1 ML/day under scenarios P, A, and C is shown in Table 15.

Flows less than 1 ML/day are defined as ‘cease-to-flow’ for the purposes of this report. The rivers in all catchments are

perennial under Scenario P, never ceasing to flow. The percentage of time that the river is flowing decreases slightly

under Scenario A compared to Scenario P in the Scamander-Douglas catchment, reflecting the impact of extractions on

low flows. There is a slight decrease in the percentage of time the river is flowing in the Boobyalla-Tomahawk catchment

under Scenarios Cdry compared to Scenario A.


Table 15. Percentage of time end-of-system flow greater than 1 ML/day under scenarios P, A and C

P A Cwet Cmid Cdry

02_Musselroe-Ansons 100% 100% 100% 100% 100%

03_George 100% 100% 100% 100% 100%

04_Scamander-Douglas 100% 99% 99% 99% 99%

42_North Esk 100% 100% 100% 100% 100%

44_Pipers 100% 100% 100% 100% 100%

45_Little Forester 100% 100% 100% 100% 100%

46_Great Forester-Brid 100% 100% 100% 100% 100%

47_Boobyalla-Tomahawk 100% 100% 100% 100% 99%

48_Ringarooma 100% 100% 100% 100% 100%

The end-of-system flow during dry periods under Scenario A with relative changes under Scenario C is shown in

Table 16. The end-of-system flow for the lowest one-, three- and five-year periods reduces in all catchments under

Scenario Cdry, with a maximum reduction of 24.3 percent in the Scamander-Douglas catchment for the lowest five-year

period. This indicates that under Scenario Cdry, the river system is more stressed in periods of low flow compared to the

long-term mean.


Table 16. End-of-system flow for catchments during dry periods under Scenario A, and under Scenario C relative to Scenario A

A Cwet Cmid Cdry


02_Musselroe-Ansons

Lowest 1-year period of EOS flow 45.2 -1.4% -6.6% -16.1%

Lowest 3-year period of EOS flow 81.7 1.3% -7.0% -17.0%


Mean annual EOS flow for 84 years 203.7 1.0% -4.3% -11.6%

03_George




Mean annual EOS flow for 84 years 258.6 -4.1% -7.7% -13.5%






42_North Esk





44_Pipers





45_Little Forester














Mean annual EOS flow for 84 years 110.9 2.7% -3.5% -10.9%

48_Ringarooma






3.5 Share of available resource

The mean annual volume of extracted and non-extracted shares of water for the Pipers-Ringarooma region under

scenarios A and C are shown in Figure 13 and Table 17. The methods for modelling extractions and allocations are

described in Section 2.1.1. The extractions include all WIMS allocations and exclude inter-catchment transfers. On an

annual basis, there is a very low volume of extracted water relative to the total mean annual volume of water in the

region. The mean annual non-extracted water decreases by 70 GL/year (3.2 percent) under Scenario Cwet relative to

Scenario A, and extracted water decreases by 1 GL/year (1.3 percent). The non-extracted water decreases by

312 GL/year (14.3 percent) under Scenario Cdry relative to Scenario A, but extracted water only decreases by 4 GL/year

(5 percent).

0

500

1000

1500

2000

2500

A Cwet Cmid Cdry

Mea

n an

nual

vol

ume

(GL)

.

Non-extracted water Extracted water

Figure 13. Extracted and non-extracted shares of water for the Pipers-Ringarooma region under scenarios A and C (annual)

Table 17. Extracted and non-extracted shares of water for the Pipers-Ringarooma region under scenarios A and C (annual)

A Cwet Cmid Cdry

GL/y

Non-extracted water 2185 2115 2007 1873

Extracted water 79 78 77 75

Total 2264 2193 2084 1948

The mean annual extracted and non-extracted shares of water for each catchment are shown in Figure 14 and Table 18.

The volume of extracted water does not change significantly under Scenario C relative to Scenario A for any catchment.

This implies that the reduction in the runoff under Scenario C would be borne more in the non-extracted proportion of

river flows due to the extraction rules. The implication of these changes for environmental values is assessed in Graham

et al. (2009).


(a) 02_Musselroe-Ansons (b) 03_George

0

50

100

150

200

250

A Cwet Cmid Cdry

Mea

n an

nual

vol

ume

(GL)

.


0

50

100

150

200

250

300

A Cwet Cmid Cdry

Mea

n an

nual

vol

ume

(GL)

.


(c) 04_Scamander-Douglas (d) 42_North Esk

020406080

100120140160180200

A Cwet Cmid Cdry

Mea

n an

nual

vol

ume

(GL)

.


050

100150200250300350400450500

A Cwet Cmid Cdry

Mea

n an

nual

vol

ume

(GL)

.


(e) 44_Pipers (f) 45_Little Forester

020406080

100120140160180200

A Cwet Cmid Cdry

Mea

n an

nual

vol

ume

(GL)

.


0

20

40

60

80

100

120

140

A Cwet Cmid Cdry

Mea

n an

nual

vol

ume

(GL)

.


(g) 46_Great Forester-Brid (h) 47_Boobyalla-Tomahawk

0

50

100

150

200

250

300

A Cwet Cmid Cdry

Mea

n an

nual

vol

ume

(GL)

.


0

20

40

60

80

100

120

140

A Cwet Cmid Cdry

Mea

n an

nual

vol

ume

(GL)

.


Figure 14. Extracted and non-extracted shares of water for catchments under scenarios A and C (annual)


(i) 48_Ringarooma

050

100150200250300350400450500

A Cwet Cmid CdryM

ean

annu

al v

olum

e (G

L) .


Figure 14. Extracted and non-extracted shares of water for catchments under scenarios A and C (annual) (continued)

Table 18. Extracted and non-extracted shares of water for catchments under scenarios A and C (annual)

A Cwet Cmid Cdry

GL/y

02_Musselroe-Ansons

Non-extracted water 203.7 205.7 194.9 180.0

Extracted water 7.9 8.0 7.8 7.6

Total 211.6 213.7 202.7 187.6

03_George



Total 260.1 249.6 240.2 225.3




Total 190.0 183.6 174.9 162.3

42_North Esk



Total 461.3 435.6 413.1 388.2

44_Pipers



Total 179.2 176.3 167.1 156.5

45_Little Forester



Total 124.7 120.2 113.7 106.5




Total 256.0 247.7 234.6 219.4




Total 116.8 119.8 112.8 104.5

48_Ringarooma



Total 464.7 446.8 424.7 397.8


The mean extracted and non-extracted shares of water for the Pipers-Ringarooma region for summer only are shown in

Table 19. The mean summer extraction does not change significantly under Scenario C relative to Scenario A. Under

Scenario A, the extracted volume of water is approximately 6 percent of the total volume in summer. The non-extracted

water decreases by 24 percent in summer under Scenario Cdry relative to Scenario A, but the extracted volume only

decreases by 5 percent.

Table 19. Extracted and non-extracted shares of water for the Pipers-Ringarooma region under scenarios A and C (summer – October

to March inclusive)

A Cwet Cmid Cdry

GL/season

Non-extracted water 628 613 548 479

Extracted water 40 40 39 38

Total 669 653 587 517

The mean extracted and non-extracted shares of water for each catchment for summer only are shown in Table 20. The

mean summer extraction does not change significantly under Scenario C relative to Scenario A, even though the volume

of non-extracted water may reduce considerably.

Table 20. Extracted and non-extracted shares of water for catchments under scenarios A and C (summer – October to March inclusive)

A Cwet Cmid Cdry

GL/season

02_Musselroe-Ansons



Total 61.6 63.4 56.6 48.3

03_George



Total 96.4 92.9 86.6 77.3




Total 65.7 63.8 58.5 50.2

42_North Esk



Total 125.8 119.1 105.9 94.1

44_Pipers



Total 32.1 32.4 27.9 24.4

45_Little Forester



Total 36.2 35.5 31.6 28.2




Total 83.1 81.5 73.3 65.7




Total 27.5 28.8 24.7 21.1

48_Ringarooma



Total 140.2 135.3 121.3 107.1


The mean percentage of water extracted as a proportion of total mean annual flow under scenarios A and C annually

and for summer and winter are shown in Table 21, Table 22 and Table 23 respectively. On an annual basis, the

percentage of water extracted as a proportion of total flow is 10 percent or less in all catchments. The proportion of the

total flow extracted in summer is the same or larger than the annual proportion of flow extracted in all catchments,

particularly the Great Forester-Brid where the proportion of water extracted in summer under Scenario A is 19 percent,

compared to 9 percent annually. There is little or no change in the percentage of extractions as a proportion of total flow

under Scenario C compared to Scenario A annually or seasonally.

Table 21. Percentage of water extracted as a proportion of total mean annual flow for catchments under scenarios A and C (annual)

Catchment A Cwet Cmid Cdry

02_Musselroe-Ansons 4% 4% 4% 4%

03_George 1% 1% 1% 1%

04_Scamander-Douglas 1% 1% 1% 1%

42_North Esk 4% 5% 5% 5%

44_Pipers 2% 2% 2% 2%

45_Little Forester 3% 3% 3% 3%

46_Great Forester-Brid 9% 9% 10% 10%

47_Boobyalla-Tomahawk 5% 5% 5% 5%

48_Ringarooma 3% 3% 3% 3%

Region mean 3% 4% 4% 4%

Table 22. Percentage of water extracted as a proportion of total mean annual flow for catchments under scenarios A and C (summer –

October to March inclusive)



03_George 1% 1% 1% 1%


42_North Esk 8% 8% 9% 10%

44_Pipers 3% 3% 3% 3%






Table 23. Percentage of water extracted as a proportion of total end-of-system flow for catchments under scenarios A and C (winter –

April to September inclusive)



03_George 0% 0% 0% 0%


42_North Esk 3% 3% 3% 3%

44_Pipers 1% 2% 2% 2%







4 Under historical climate (Scenario A) and recent

climate (Scenario B)

This section compares recent hydrology (under Scenario B) with historical hydrology (under Scenario A). The mean

end-of-system (EOS) flow in GL/year, and daily EOS flow duration curves are shown in Figure 15 for each catchment.

Autumn and winter flows are lower in all catchments under recent climate relative to historical climate. The flow duration

curves show that flows under recent climate have generally been lower than the long-term mean over the full range of

flows.

(a-1) 02_Musselroe-Ansons – monthly flow (a-2) 02_Musselroe-Ansons – daily flow duration

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4


EO

S m

onth

ly fl

ow (

GL)

. B

A

1

10

100

1000

10000

100000


EO

S d

aily

flow

(M

L) .

B

A

(b-1) 03_George – monthly flow (b-2) 03_George – daily flow duration

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4


EO

S m

onth

ly fl

ow (

GL)

. B

A

1

10

100

1000

10000

100000


EO

S d

aily

flow

(M

L) .

B

A

(c-1) 04_Scamander-Douglas – monthly flow (c-2) 04_Scamander-Douglas – daily flow duration

0.00.10.20.30.40.50.60.70.80.9


EO

S m

onth

ly fl

ow (

GL)

. B

A

1

10

100

1000

10000

100000


EO

S d

aily

flow

(M

L) .

B

A

Figure 15. Mean end-of-system monthly flow and daily flow duration curves for catchments under scenarios A and B


(d-1) 42_North Esk – monthly flow (d-2) 42_North Esk – daily flow duration

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5


EO

S m

onth

ly fl

ow (

GL)

. B

A

1

10

100

1000

10000

100000


EO

S d

aily

flow

(M

L) .

B

A

(e-1) 44_Pipers – monthly flow (e-2) 44_Pipers – daily flow duration

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6


EO

S m

onth

ly fl

ow (

GL)

. B

A

1

10

100

1000

10000

100000


EO

S d

aily

flow

(M

L) .

B

A

(f-1) 45_Little Forester – monthly flow (f-2) 45_Little Forester – daily flow duration

0.00.10.20.30.40.50.60.70.80.9


EO

S m

onth

ly fl

ow (

GL)

. B

A

1

10

100

1000

10000

100000


EO

S d

aily

flow

(M

L) .

B

A

(g-1) 46_Great Forester-Brid – monthly flow (g-2) 46_Great Forester-Brid – daily flow duration

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6


EO

S m

onth

ly fl

ow (

GL)

. B

A

1

10

100

1000

10000

100000


EO

S d

aily

flow

(M

L) .

B

A

Figure 15. Mean end-of-system monthly flow and daily flow duration curves for catchments under scenarios A and B (continued)


(h-1) 47_Boobyalla-Tomahawk – monthly flow (h-2) 47_Boobyalla-Tomahawk – daily flow duration

0.00.10.20.30.40.50.60.70.80.9


EO

S m

onth

ly fl

ow (

GL)

. B

A

1

10

100

1000

10000

100000


EO

S d

aily

flow

(M

L) .

B

A

(i-1) 48_Ringarooma – monthly flow (i-2) 48_Ringarooma – daily flow duration

0.0

0.5

1.0

1.5

2.0

2.5

3.0


EO

S m

onth

ly fl

ow (

GL)

. B

A

1

10

100

1000

10000

100000


EO

S d

aily

flow

(M

L) .

B

A

Figure 15. Mean end-of-system monthly flow and daily flow duration curves for catchments under scenarios A and B (continued)

The mean annual extracted and non-extracted shares of water for the Pipers-Ringarooma region under scenarios A and

B are shown in Figure 16 and Table 24. The total water in the region is 535 GL/year lower under Scenario B; however,

the volume of extracted water reduces by only 4 GL/year, reflecting the low level of extraction on a regional basis as well

as the extraction rules in place. The reduction in the total EOS flow under Scenario B relative to Scenario A is borne by

the non-extracted water. The implication of these changes for environmental values is assessed in Graham et al. (2009).

0

500

1000

1500

2000

2500

A B

Mea

n an

nual

vol

ume

(GL)

.


Figure 16. Mean annual extracted and non-extracted shares of water for the Pipers-Ringarooma region under scenarios A and B


Table 24. Mean annual extracted and non-extracted shares of water for the Pipers-Ringarooma region under scenarios A and B

A B

GL/y

Non-extracted water 2185 1650

Extracted water 79 75

Total 2264 1725

The extracted and non-extracted shares of water under scenarios A and B for summer only are shown in Table 25. There

is a large decrease in mean summer flows under Scenario B relative to Scenario A. This has only a minimal impact on

the mean summer extraction volume, reflecting the low level of water usage on a regional basis and the extraction rules

in place.

Table 25. Extracted and non-extracted shares of water for the Pipers-Ringarooma region under scenarios A and B (summer – October

to March inclusive)

A B

GL/season

Non-extracted water 628 547

Extracted water 40 38

Total 669 585

The mean annual extracted and non-extracted shares of water are shown in Table 26 for each catchment under

scenarios A and B. The mean annual volume of total water is reduced under Scenario B relative to Scenario A in all

catchments. The volume of water extracted is slightly less under Scenario B relative to Scenario A in all catchments,

except for the George catchment, where it is the same.

The extracted and non-extracted shares of water for each catchment for summer only under scenarios A and B are

shown in Table 27. The mean summer volume of water extracted does not vary greatly under Scenario B compared to

Scenario A in the majority of catchments. The largest impact is in the Great Forester-Brid catchment where the mean

volume of water extracted over summer is 13.5 GL/summer under Scenario B and 15.6 GL/summer under Scenario A.


Table 26. Mean annual extracted and non-extracted shares of water for catchments under scenarios A and B

A B

GL/y

02_Musselroe-Ansons

Non-extracted water 203.7 133.0

Extracted water 7.9 7.5

Total 211.6 140.5

03_George



Total 260.1 203.9




Total 190.0 130.9

42_North Esk



Total 461.3 379.5

44_Pipers



Total 179.2 134.4

45_Little Forester



Total 124.7 95.2




Total 256.0 189.6




Total 116.8 82.4

48_Ringarooma



Total 464.7 368.4


Table 27. Extracted and non-extracted shares of water under scenarios A and B (summer – October to March inclusive)

A B

GL/season

02_Musselroe-Ansons



Total 61.6 53.5

03_George



Total 96.4 87.0




Total 65.7 62.8

42_North Esk



Total 125.8 109.7

44_Pipers



Total 32.1 28.9

45_Little Forester



Total 36.2 29.8




Total 83.1 65.7




Total 27.5 24.2

48_Ringarooma



Total 140.2 123.7


5 Under future development (Scenario D)

The impacts of future development under future climate are modelled in Scenario D. These developments include

proposed irrigation developments and projected future expansion in commercial forestry. The impacts of future

development are shown relative to Scenario C, which models future climate with current infrastructure.

5.1 Reliability of proposed irrigation developments

The mean allocated and extracted water for the proposed irrigation schemes are shown in Table 28. The mean allocated

water reflects the mean annual demand figures supplied by the Tasmanian Irrigation Development Board (Section 2.2.2,

Table 5). The extracted water is mean annual volume of water which was able to be extracted for each scheme. As these

are summer extractions, statistics were calculated on a water-year basis from July to June. Most schemes have a high

mean annual reliability of extractions of 86 percent or greater under Scenario D. The exceptions are the St Patricks River

Dam, which has a reliability of 71 percent under Scenario Ddry, and the Monarch Mines Dam which has a reliability of

42 percent under Scenario Ddry.

All proposed developments from the Great Forester River were modelled together, which means that the performance of

the downstream scheme will be affected by the proposed upstream extractions; however, all of these dams have

reliabilities greater than 90 percent. The developments proposed on the Great Forester River are the Headquarters Road

Dam, Maryvale Dam, Great Forester River Dam and the Oxberry Dam, with the Headquarters Road Dam most upstream

and the Oxberry Dam most downstream.


Table 28. Comparison of allocated and extracted water under Scenario D schemes

Dwet Dmid Ddry

GL/y

St Patricks River Dam

Allocated water 17.0 17.0 17.0

Extraction 13.6 12.9 12.1

Percent extraction 80% 76% 71%

Monarch Mines Dam




Brid River Dam




Great Forester River Dam




Oxberry Dam




Maryvale Dam




Headquarters Road Dam




Little Forester River Dam




Great Musselroe River Dam




Tomahawk River Dam




The allocated and extracted water over the 83 water-years are shown in Figure 17. The allocated volume of water varies

year to year, depending on the modelled demand (Section 2.2.2). The mean allocated water reflects the mean annual

demand figures supplied by the Tasmanian Irrigation Development Board (Section 2.2.2, Table 5). The extracted volume

is 100 percent of the allocated volume for all years on the Brid, Great Forester, Little Forester and Great Musselroe dams,

for more than 90 percent of years for the Maryvale and Headquarters Road dams, and for more than 80 percent of years

for the Oxberry Dam. The extracted volume is more than 90 percent of the allocated volume for 75 percent of years for

the Tomahawk Dam, but only 40 percent of the time for St Patricks River Dam, and less than 20 percent of the time for

Monarch Mines Dam. The reliability of the St Patricks River Dam is projected to be less than 15 percent in the driest year.

The reliability of Monarch Mines Dam is projected to be less than 10 percent in the driest year.


(a-1) St Patricks River Dam – allocated water (a-2) St Patricks River Dam – extracted per unit allocated

0

4

8

12

16

20

24

28


Ann

ual v

olum

e (G

L) .

D range

Dmid

0.0

0.2

0.4

0.6

0.8

1.0

0% 20% 40% 60% 80% 100%


Ext

ract

ed v

olum

e pe

r .

unit

allo

cate

d .

D range

Dmid

(b-1) Monarch Mines Dam – allocated water (b-2) Monarch Mines Dam – extracted per unit allocated

0

1

2

3

4


Ann

ual v

olum

e (G

L) .

D range

Dmid

0.0

0.2

0.4

0.6

0.8

1.0

0% 20% 40% 60% 80% 100%


Ext

ract

ed v

olum

e pe

r .

unit

allo

cate

d .

D range

Dmid

(c-1) Brid River Dam – allocated water (c-2) Brid River Dam – extracted per unit allocated

0.0

0.5

1.0

1.5

2.0

2.5

3.0


Ann

ual v

olum

e (G

L) .

D range

Dmid

0.0

0.2

0.4

0.6

0.8

1.0

0% 20% 40% 60% 80% 100%


Ext

ract

ed v

olum

e pe

r .

unit

allo

cate

d .

D range

Dmid

(d-1) Great Forester River Dam – allocated water (d-2) Great Forester River Dam – extracted per unit allocated

0

1

2

3

4

5

6


Ann

ual v

olum

e (G

L) .

D range

Dmid

0.0

0.2

0.4

0.6

0.8

1.0

0% 20% 40% 60% 80% 100%


Ext

ract

ed v

olum

e pe

r .

unit

allo

cate

d .

D range

Dmid

Figure 17. Allocation and extraction reliability under Scenario D schemes


(e-1) Oxberry Dam – allocated water (e-2) Oxberry Dam – extracted per unit allocated

0

1

2

3

4

5

6


Ann

ual v

olum

e (G

L) .

D range

Dmid

0.0

0.2

0.4

0.6

0.8

1.0

0% 20% 40% 60% 80% 100%


Ext

ract

ed v

olum

e pe

r .

unit

allo

cate

d .

D range

Dmid

(f-1) Maryvale Dam – allocated water (f-2) Maryvale Dam – extracted per unit allocated

0

1

2

3

4

5


Ann

ual v

olum

e (G

L) .

D range

Dmid

0.0

0.2

0.4

0.6

0.8

1.0

0% 20% 40% 60% 80% 100%


Ext

ract

ed v

olum

e pe

r .

unit

allo

cate

d .

D range

Dmid

(g-1) Headquarters Road Dam – allocated water (g-2) Headquarters Road Dam – extracted per unit allocated

0.0

0.5

1.0

1.5

2.0

2.5


Ann

ual v

olum

e (G

L) .

D range

Dmid

0.0

0.2

0.4

0.6

0.8

1.0

0% 20% 40% 60% 80% 100%


Ext

ract

ed v

olum

e pe

r .

unit

allo

cate

d .

D range

Dmid

(h-1) Little Forester River Dam – allocated water (h-2) Little Forester River Dam – extracted per unit allocated

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0


Ann

ual v

olum

e (G

L) .

D range

Dmid

0.0

0.2

0.4

0.6

0.8

1.0

0% 20% 40% 60% 80% 100%


Ext

ract

ed v

olum

e pe

r .

unit

allo

cate

d .

D range

Dmid

Figure 17. Allocation and extraction reliability under Scenario D schemes (continued)


(i-1) Great Musselroe River Dam – allocated water

(i-2) Great Musselroe River Dam – extracted per unit allocated

0

4

8

12

16

20

24


Ann

ual v

olum

e (G

L) .

D range

Dmid

0.0

0.2

0.4

0.6

0.8

1.0

0% 20% 40% 60% 80% 100%


Ext

ract

ed v

olum

e pe

r .

unit

allo

cate

d .

D range

Dmid

(j-1) Tomahawk River Dam – allocated water (j-2) Tomahawk River Dam – extracted per unit allocated

0

2

4

6

8

10

12


Ann

ual v

olum

e (G

L) .

D range

Dmid

0.0

0.2

0.4

0.6

0.8

1.0

0% 20% 40% 60% 80% 100%


Ext

ract

ed v

olum

e pe

r .

unit

allo

cate

d .

D range

Dmid

Figure 17. Allocation and extraction reliability under Scenario D schemes (continued)

The volume of water extracted in dry periods is shown in Table 29. The volume of water extracted for the lowest periods

of extraction is lower than the mean annual extraction for all schemes, indicating that the schemes will be less reliable

during dry periods; however, this varies considerably between the schemes. The St Patricks, Tomahawk and Monarch

Mines dams show particularly large reductions in extractions during dry periods relative to the mean annual extraction.


Table 29. Indicators of use during dry periods under Scenario D schemes

Dwet Dmid Ddry

GL/y

St Patricks River Dam

Lowest 1-year (water year) period of extraction 2.9 2.7 2.5



Mean annual extraction for 84 years 13.6 12.9 12.1

Monarch Mines Dam




Mean water-year extraction for 84 years 1.3 1.2 1.1

Brid River Dam

Lowest 1-year period of extraction 1.1 1.1 1.2




Great Forester River Dam





Oxberry Dam





Maryvale Dam





Headquarters Road Dam





Little Forester River Dam





Great Musselroe River Dam





Tomahawk River Dam






5.2 Hydrologic impacts of future development

The projected changes in mean annual inflows from catchment runoff as a percent difference under Scenario D relative

to Scenario C are shown in Table 30. Scenario D represents future expansion in commercial forestry and irrigation under

future climate. The largest projected change in inflows due to increases in commercial forestry is in the Pipers catchment

where inflows decrease by up to 4.9 percent under Scenario D relative to Scenario C. This reflects the fact that the

largest projected increase in future forestry is concentrated in this catchment (Viney et al., 2009), as shown in Figure 5.

Table 30. Comparison of inflows from catchment runoff under Scenario D relative to Scenario C

Dwet Dmid Ddry

percent change relative to Cwet

percent change relative to Cmid

percent change relative to Cdry

02_Musselroe-Ansons -1.4% -1.4% -1.4%

03_George -0.8% -0.8% -0.9%

04_Scamander-Douglas -0.2% -0.2% -0.2%

42_North Esk -1.3% -1.4% -1.4%

44_Pipers -4.8% -4.9% -4.9%

45_Little Forester -2.1% -2.1% -2.1%

46_Great Forester-Brid -1.0% -1.0% -1.0%

47_Boobyalla-Tomahawk -3.4% -3.4% -3.4%

48_Ringarooma -1.3% -1.3% -1.3%

Region mean -1.6% -1.6% -1.6%

The projected changes in end-of-system (EOS) flows are shown in Table 31 as change in percentage of time EOS flows

are greater than 1 ML. There are only very minor changes under Scenario D relative to Scenario C in most catchments,

indicating that future development will not impact on the percentage of time rivers cease-to-flow in this region. In the

Boobyalla-Tomahawk catchment, the river ceases to flow 5 percent of the time under Scenario Ddry compared to

1 percent of the time under Scenario Cdry.

Table 31. Percent time end-of-system flow for catchments is greater than 1 ML under Scenario D relative to Scenario C

Cwet Cmid Cdry Dwet Dmid Ddry

percentage of time EOS flow >1 ML

02_Musselroe-Ansons 100% 100% 100% 100% 100% 100%

03_George 100% 100% 100% 100% 100% 100%

04_Scamander-Douglas 99% 99% 99% 99% 99% 98%

42_North Esk 100% 100% 100% 100% 100% 100%

44_Pipers 100% 100% 100% 99% 99% 99%

45_Little Forester 100% 100% 100% 100% 100% 100%

46_Great Forester-Brid 100% 100% 100% 100% 100% 100%

47_Boobyalla-Tomahawk 100% 100% 99% 96% 96% 95%

48_Ringarooma 100% 100% 100% 100% 100% 100%

Extractions under Scenario C and relative changes under Scenario D are shown in Table 32. The change in extractions

under Scenario D relative to Scenario C is greater than the change in runoff in the Musselroe-Ansons, Great

Forester-Brid, Boobyalla-Tomahawk and Ringarooma catchments. This is particularly seen in the Musselroe-Ansons

catchment where the reliability of extractions is low under scenarios A and C. All extractions in this catchment are

surety 5 and assumed proportion of unlicensed extractions. The impact on extractions is also seen in the Great Forester-

Brid catchment where the reduction in flows will reduce allocations due to the restriction rules in place in this catchment.

In the Pipers catchment, where there is the greatest reduction in runoff due to changes in forestry (up to 4.9 percent), the

extractions reduce by only 2.9 percent under Scenario Ddry relative to Scenario Cdry.


Table 32. Comparison of current extractions for catchments under Scenario D relative to Scenario C


GL/y percent change relative to Cwet



02_Musselroe-Ansons

Surety 1 0.0 0.0 0.0 - - -

Surety 2 0.0 0.0 0.0 - - -

Surety 3 0.0 0.0 0.0 - - -

Surety 4 0.0 0.0 0.0 - - -

Surety 5 4.6 4.5 4.4 -4.6% -4.8% -5.2%

Surety 6 0.1 0.1 0.1 0.0% 0.0% 0.0%

Surety 7 0.0 0.0 0.0 - - -

Surety 8 0.0 0.0 0.0 - - -

Unlicensed 3.3 3.2 3.1 -14.1% -15.9% -18.9%

Total extractions 8.0 7.8 7.6 -8.5% -9.3% -10.7%

03_George

Surety 1 0.0 0.0 0.0 0.0% 0.0% 0.0%

Surety 2 0.0 0.0 0.0 - - -

Surety 3 0.0 0.0 0.0 - - -

Surety 4 0.0 0.0 0.0 - - -

Surety 5 0.7 0.7 0.7 0.0% 0.0% 0.0%

Surety 6 0.1 0.1 0.1 0.0% 0.0% 0.0%

Surety 7 0.0 0.0 0.0 - - -

Surety 8 0.0 0.0 0.0 - - -

Unlicensed 0.7 0.7 0.7 0.0% 0.0% 0.0%

Total extractions 1.5 1.5 1.5 0.0% 0.0% 0.0%


Surety 1 0.0 0.0 0.0 0.0% 0.0% 0.0%

Surety 2 0.0 0.0 0.0 - - -

Surety 3 0.0 0.0 0.0 - - -

Surety 4 0.0 0.0 0.0 - - -

Surety 5 0.7 0.7 0.7 -0.1% -0.1% 0.0%

Surety 6 0.0 0.0 0.0 - - -

Surety 7 0.0 0.0 0.0 - - -

Surety 8 0.0 0.0 0.0 - - -

Unlicensed 0.8 0.8 0.8 -0.1% -0.1% -0.1%


42_North Esk

Surety 1 11.5 11.5 11.5 -0.1% -0.1% -0.1%

Surety 2 0.0 0.0 0.0 - - -

Surety 3 0.0 0.0 0.0 - - -

Surety 4 5.6 5.6 5.6 -0.6% -0.8% -1.0%

Surety 5 1.6 1.6 1.5 -11.8% -12.1% -12.5%

Surety 6 0.1 0.1 0.1 -2.5% -2.3% -1.8%

Surety 7 0.0 0.0 0.0 - - -

Surety 8 0.0 0.0 0.0 - - -

Unlicensed 0.8 0.8 0.8 -0.9% -0.8% -0.7%



Table 32. Comparison of current extractions for catchments under Scenario D relative to Scenario C (continued)





44_Pipers

Surety 1 0.2 0.2 0.2 -4.4% -4.5% -4.1%

Surety 2 0.0 0.0 0.0 - - -

Surety 3 0.0 0.0 0.0 - - -

Surety 4 0.0 0.0 0.0 - - -

Surety 5 1.3 1.3 1.3 -2.4% -2.3% -2.1%

Surety 6 0.0 0.0 0.0 - - -

Surety 7 0.0 0.0 0.0 - - -

Surety 8 0.0 0.0 0.0 - - -

Unlicensed 1.5 1.5 1.5 -3.2% -3.1% -2.9%


45_Little Forester

Surety 1 0.0 0.0 0.0 0.0% 0.0% 0.0%

Surety 2 0.0 0.0 0.0 - - -

Surety 3 0.0 0.0 0.0 - - -

Surety 4 0.0 0.0 0.0 - - -

Surety 5 3.0 3.0 3.0 -1.5% -1.5% -1.5%

Surety 6 0.1 0.1 0.1 -1.2% -1.9% -3.1%

Surety 7 0.0 0.0 0.0 - - -

Surety 8 0.0 0.0 0.0 - - -

Unlicensed 0.3 0.3 0.3 -2.5% -2.5% -2.4%



Surety 1 0.9 0.9 0.9 -1.9% -1.9% -2.0%

Surety 2 0.0 0.0 0.0 - - -

Surety 3 0.2 0.2 0.2 0.0% 0.0% 0.0%

Surety 4 0.0 0.0 0.0 - - -

Surety 5 8.7 8.6 8.5 -4.8% -4.9% -5.1%

Surety 6 12.7 12.1 11.2 -7.0% -7.4% -7.8%

Surety 7 0.0 0.0 0.0 - - -

Surety 8 0.0 0.0 0.0 - - -

Unlicensed 0.8 0.8 0.8 -0.7% -0.7% -0.6%



Surety 1 0.1 0.1 0.1 -1.5% -1.5% -1.6%

Surety 2 0.0 0.0 0.0 - - -

Surety 3 0.0 0.0 0.0 - - -

Surety 4 0.0 0.0 0.0 - - -

Surety 5 5.2 5.2 5.1 -6.0% -6.1% -6.2%

Surety 6 0.0 0.0 0.0 0.0% 0.0% 0.0%

Surety 7 0.0 0.0 0.0 - - -

Surety 8 0.0 0.0 0.0 - - -

Unlicensed 0.6 0.6 0.6 -1.3% -1.1% -1.0%



Table 32. Comparison of current extractions for catchments under Scenario D relative to Scenario C (continued)





48_Ringarooma

Surety 1 1.2 1.2 1.2 -0.1% -0.2% -0.2%

Surety 2 0.0 0.0 0.0 - - -

Surety 3 0.0 0.0 0.0 - - -

Surety 4 0.0 0.0 0.0 - - -

Surety 5 8.3 8.2 8.1 -3.1% -3.1% -3.1%

Surety 6 1.5 1.5 1.5 -1.9% -1.8% -1.7%

Surety 7 0.0 0.0 0.0 - - -

Surety 8 0.0 0.0 0.0 - - -

Unlicensed 0.6 0.6 0.6 -1.3% -1.2% -1.1%


Total

Surety 1 13.9 13.9 13.9 -0.2% -0.3% -0.3%

Surety 2 0.0 0.0 0.0 - - -

Surety 3 0.2 0.2 0.2 0.0% 0.0% 0.0%

Surety 4 5.6 5.6 5.6 -0.6% -0.8% -1.0%

Surety 5 34.2 33.9 33.4 -4.3% -4.4% -4.5%

Surety 6 14.6 14.0 13.1 -6.3% -6.6% -6.9%

Surety 7 0.0 0.0 0.0 - - -

Surety 8 0.0 0.0 0.0 - - -

Unlicensed 9.5 9.3 9.2 -5.8% -6.3% -7.2%


The mean monthly EOS flow under scenarios P, A and C, and percent change in EOS flow under Scenario D relative to

Scenario C are shown in Figure 18. The changes under Scenario D are due to both changes in forestry and the

proposed irrigation dams. The largest percentage change is generally observed in January to April where reductions in

EOS flows of up to 30 percent can be seen in the Little Forester catchment, 28 percent in the Great Forester catchment

and 18 percent in the Boobyalla-Tomahawk catchment. All these catchments include proposed irrigation developments

which will capture low flows in in-stream storages. As the volume of flows is relatively low in these months, the volumetric

change in flows is small.

The increase in flows in September in the Musselroe-Ansons, Little Forester and Great Forester-Brid catchments is due

to the environmental release rules included for new irrigation schemes to allow annual and biennial release of flood flows.

These flows were released from the storages in September if there was no natural flow exceeding the flood release

volume.


(a-1) 02_Musselroe-Ansons – monthly flows (scenarios P, A and C)

(a-2) 02_Musselroe-Ansons – percent change in monthly flows (Scenario D)

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4


EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

-35-30-25-20-15-10

-505

10


Per

cent

cha

nge

in E

OS

mon

thly

flow

rel

ativ

e .

to S

cena

rio

C .

D range

Dmid

(b-1) 03_George – monthly flows (scenarios P, A and C) (b-2) 03_George – percent change in monthly flows

(Scenario D)

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4


EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

-35-30-25-20-15-10

-505

10


Per

cent

cha

nge

in E

OS

mon

thly

flow

rel

ativ

e .

to S

cena

rio

C .

D range

Dmid

(c-1) 04_Scamander-Douglas – monthly flows (scenarios P, A and C)

(c-2) 04_Scamander-Douglas – percent change in monthly flows (Scenario D)

0.00.10.20.30.40.50.60.70.80.9


EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

-35-30-25-20-15-10

-505

10


Per

cent

cha

nge

in E

OS

mon

thly

flow

rel

ativ

e .

to S

cena

rio

C .

D range

Dmid

(d-1) 42_North Esk – monthly flows (scenarios P, A and C) (d-2) 42_North Esk – percent change in monthly flows

(Scenario D)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5


EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

-35-30-25-20-15-10

-505

10


Per

cent

cha

nge

in E

OS

mon

thly

flow

rel

ativ

e .

to S

cena

rio

C .

D range

Dmid

Figure 18. Mean monthly end-of-system flow under scenarios P, A, and C; and changes under Scenario D relative to Scenario C


(e-1) 44_Pipers – monthly flows (scenarios P, A and C) (e-2) 44_Pipers – percent change in monthly flows (Scenario D)

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6


EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

-35-30-25-20-15-10

-505

10


Per

cent

cha

nge

in E

OS

mon

thly

flow

rel

ativ

e .

to S

cena

rio

C .

D range

Dmid

(f-1) 45_Little Forester – monthly flows (scenarios P, A and C)

(f-2) 45_Little Forester – percent change in monthly flows (Scenario D)

0.00.10.20.30.40.50.60.70.80.9


EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

-35-30-25-20-15-10

-505

10


Per

cent

cha

nge

in E

OS

mon

thly

flow

rel

ativ

e .

to S

cena

rio

C .

D range

Dmid

(g-1) 46_Great Forester-Brid – monthly flows (scenarios P, A and C)

(g-2) 46_Great Forester-Brid – percent change in monthly flows (Scenario D)

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6


EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

-35-30-25-20-15-10

-505

10


Per

cent

cha

nge

in E

OS

mon

thly

flow

rel

ativ

e .

to S

cena

rio

C .

D range

Dmid

(h-1) 47_Boobyalla-Tomahawk – monthly flows (scenarios P, A and C)

(h-2) 47_Boobyalla-Tomahawk – percent change in monthly flows (Scenario D)

0.00.10.20.30.40.50.60.70.80.9


EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

-35-30-25-20-15-10

-505

10


Per

cent

cha

nge

in E

OS

mon

thly

flow

rel

ativ

e .

to S

cena

rio

C .

D range

Dmid


(continued)


(i-1) 48_Ringarooma – monthly flows (scenarios P, A and C)

(i-2) 48_Ringarooma – percent change in monthly flows (Scenario D)

0.0

0.5

1.0

1.5

2.0

2.5

3.0


EO

S m

onth

ly fl

ow (

GL)

. C rangeCmidAP

-35-30-25-20-15-10

-505

10


Per

cent

cha

nge

in E

OS

mon

thly

flow

rel

ativ

e .

to S

cena

rio

C .

D range

Dmid


(continued)

Peak flows under Scenario C and relative changes under Scenario D are shown in Table 33. Peak flows are reduced for

all return periods in all catchments under Scenario D relative to Scenario C, showing that high flows are impacted by

future development. These impacts are outcomes of the FCFC modelling used to determine the effects of forestry on

streamflow (see Viney et al., 2009) and impoundments for the irrigation developments.


Table 33. Comparison of change in peak flows for catchments under Scenario D relative to Scenario C


ML/d percent change relative to Cwet



02_Musselroe-Ansons

2-year 9,163 8,803 8,332 -9.05% -7.80% -10.03%

5-year 14,039 13,191 12,525 -7.01% -8.30% -9.44%

10-year 16,078 15,921 15,847 -4.11% -6.64% -13.09%

03_George

2-year 7,442 6,909 6,617 -0.23% -0.28% -0.29%

5-year 12,700 12,456 11,881 -0.21% -0.22% -0.27%

10-year 16,493 16,317 15,732 -0.22% -0.26% -0.29%


2-year 15,829 15,346 14,464 -0.37% -0.14% -0.33%

5-year 25,725 24,999 22,106 -0.33% -0.26% -0.22%

10-year 29,355 30,949 30,069 -0.14% -0.12% -0.18%

42_North Esk

2-year 10,895 10,319 9,868 -4.56% -3.95% -4.12%

5-year 14,558 14,166 13,457 -4.04% -4.35% -4.36%

10-year 17,523 17,304 16,400 -4.47% -4.61% -4.43%

44_Pipers

2-year 7,811 7,348 7,151 -4.69% -4.63% -4.64%

5-year 10,248 10,126 9,629 -4.42% -4.35% -4.47%

10-year 12,029 11,474 10,876 -4.64% -4.57% -4.98%

45_Little Forester

2-year 3,104 2,950 2,771 -0.93% -1.08% -0.72%

5-year 3,955 3,846 3,687 -0.44% -0.55% -0.52%

10-year 4,386 4,297 4,114 -0.89% -0.79% -0.79%


2-year 4,355 4,226 3,943 -4.06% -10.70% -5.71%

5-year 6,242 6,106 5,764 -2.57% -3.28% -5.99%

10-year 7,835 7,742 7,357 -2.05% -2.15% -3.30%


2-year 4,116 3,649 3,279 -13.22% -8.96% -9.03%

5-year 6,399 6,158 5,692 -15.11% -13.79% -15.20%

10-year 7,804 7,732 7,282 -6.85% -8.60% -5.00%

48_Ringarooma

2-year 9,213 8,250 7,874 -0.71% -0.61% -0.64%

5-year 12,792 11,839 11,162 -0.58% -0.57% -0.64%

10-year 15,016 14,752 14,293 -0.62% -0.70% -0.54%


6 Conclusions

The Pipers-Ringarooma region has a mean annual flow of 2264 GL/year, and a low level of extraction with a mean

annual extraction of 79 GL/year (3.5 percent of total water in the region). The volume of allocated water varies each year

in many catchments, due to restriction rules which limit extractions during periods of low flow.

The volume of water extracted in the region is not predicted to reduce significantly under future climate (Scenario C)

relative to historical climate (Scenario A). The largest impact is seen in the driest years. By comparison, future climate

has a greater impact on total end-of-system flows than it does on extractions.

Peak flows were evaluated for return periods of two, five and ten years. Peak flows are predicted to range between a

small decrease and a small increase under Scenario Cwet relative to Scenario A over all catchments. Peak flows are

predicted to decrease in all catchments under Scenario Cdry relative to Scenario A for all return periods.

Under the recent climate (Scenario B), the mean monthly flow is lower than the long-term mean in all catchments in

autumn and winter. The flow duration curves show that flows under recent climate have generally been lower than the

long-term mean over the full range of flows. The volume of extracted water decreases by a mean of 4 GL/year

(5 percent) under Scenario B relative to Scenario A. The volume of non-extracted water decreases in all catchments

under Scenario B relative to Scenario A by a mean of 535 GL/year (24 percent) over the region as a whole.


plantations increasing total forest cover from 25 percent of the region to 27 percent of the region by 2030. The increase

is spread throughout the region with the largest increases in the north-west. Catchment runoff is projected to decrease by

a maximum of 4.9 percent in the Pipers catchment due to the expansion of forestry plantations.

Ten irrigation dams are proposed in the region. These dams include: St Patricks River, Monarch Mines, Brid River, Great

Forester River, Oxberry, Maryvale, Headquarters Road, Little Forester River, Great Musselroe River and Tomahawk

River dams. The total mean annual demand for all the proposed dams is 62.8 GL/year. The extracted volume is

100 percent of the allocated volume for all years on the Brid, Great Forester, Little Forester and Great Musselroe dams,

for more than 90 percent of years for the Maryvale and Headquarters Road dams, and for more than 75 percent of years

for the Oxberry Dam. The extracted volume is more than 90 percent of the allocated volume for 75 percent of years for

the Tomahawk Dam, but only 40 percent of years for St Patricks River Dam, and less than 20 percent of years for

Monarch Mines Dam.


7 References

Catchment Simulation Solutions (2009) Catchment-Sim. Viewed 10 September 2009, <http://www.csse.com.au/index.php?option=com_content&task=view&id=66&Itemid=127>.

CSIRO (2008) Water availability in the Murrumbidgee. A report to the Australian Government from the CSIRO Murray-Darling Basin Sustainable Yields Project. CSIRO, Australia.

DPIPWE (2009) Applying for a Water Licence. Department of Primary Industries, Parks, Water and Environment, Hobart. Viewed 6 August 2009, <http://www.dpiw.tas.gov.au/inter.nsf/WebPages/JMUY-4YA86N?open#SuretyLevels>.

Freshwater Systems (2004) Headquarters Road Dam – Environmental Flows Assessment. Aquatic Environmental Consulting Services, PE Davies, March 2004.

Graham B, Hardie S, Gooderham J, Gurung S, Hardie D, Marvanek S, Bobbi C, Krasnicki T and Post DA (2009) Ecological impacts of water availability for Tasmania. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Kisters (2009) Hydstra/MO network modelling, Kisters Pioneering Technologies. Viewed 10 August 2009, <http://www.kisters.de/english/html/au/homepage.html>.

Ling FLN, Gupta V, Willis M, Bennett JC, Robinson KA, Paudel K, Post DA and Marvanek S (2009a) River modelling for Tasmania. Volume 1: the Arthur-Inglis-Cam region. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Ling FLN, Gupta V, Willis M, Bennett JC, Robinson KA, Paudel K, Post DA and Marvanek S (2009b) River modelling for Tasmania. Volume 2: the Mersey-Forth region. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Ling FLN, Gupta V, Willis M, Bennett JC, Robinson KA, Paudel K, Post DA and Marvanek S (2009c) River modelling for Tasmania. Volume 3: the Pipers-Ringarooma region. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Ling FLN, Gupta V, Willis M, Bennett JC, Robinson KA, Paudel K, Post DA and Marvanek S (2009d) River modelling for Tasmania. Volume 4: the South Esk region. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Ling FLN, Gupta V, Willis M, Bennett JC, Robinson KA, Paudel K, Post DA and Marvanek S (2009e) River modelling for Tasmania. Volume 5: the Derwent-South East region. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Post DA, Chiew FHS, Teng J, Vaze J, Yang A, Mpelasoka F, Smith I, Katzfey J, Marston F, Marvanek S, Kirono D, Nguyen K, Kent D, Donohue R, Li L and McVicar T (2009) Production of climate scenarios for Tasmania. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Viney NR, Post DA, Yang A, Willis M, Robinson KA, Bennett JC, Ling FLN and Marvanek S (2009) Rainfall-runoff modelling for Tasmania. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Willis M (2008) TasCatch Finalisation Report – Stage 1 & Stage 2. HTC Report Consult-20294, for Department of Primary Industries and Water. Hydro Tasmania Consulting, Hobart.

Willis M, Bennett J, Robinson K, Ling F, Gupta V (2009) Tasmania Sustainable Yields River Modelling Methods Report. Hydro Tasmania Consulting, Hobart. in prep.

Tasmania Sustainable Yields Project reports

Region reports

CSIRO (2009) Water availability for Tasmania. Report one of seven to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

CSIRO (2009) Climate change projections and impacts on runoff for Tasmania. Report two of seven to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

CSIRO (2009) Water availability for the Arthur-Inglis-Cam region. Report three of seven to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

CSIRO (2009) Water availability for the Mersey-Forth region. Report four of seven to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

CSIRO (2009) Water availability for the Pipers-Ringarooma region. Report five of seven to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

CSIRO (2009) Water availability for the South Esk region. Report six of seven to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

CSIRO (2009) Water availability for the Derwent-South East region. Report seven of seven to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Technical reports

Graham B, Hardie S, Gooderham J, Gurung S, Hardie D, Marvanek S, Bobbi C, Krasnicki T and Post DA (2009) Ecological impacts of water availability for Tasmania. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Harrington GA, Crosbie R, Marvanek S, McCallum J, Currie D, Richardson S, Waclawik V, Anders L, Georgiou J, Middlemis H and Bond K (2009) Groundwater assessment and modelling for Tasmania. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Ling FLN, Gupta V, Willis M, Bennett JC, Robinson KA, Paudel K, Post DA and Marvanek S (2009) River modelling for Tasmania. Volume 1: the Arthur-Inglis-Cam region. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Ling FLN, Gupta V, Willis M, Bennett JC, Robinson KA, Paudel K, Post DA and Marvanek S (2009) River modelling for Tasmania. Volume 2: the Mersey-Forth region. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Ling FLN, Gupta V, Willis M, Bennett JC, Robinson KA, Paudel K, Post DA and Marvanek S (2009) River modelling for Tasmania. Volume 3: the Pipers-Ringarooma region. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Ling FLN, Gupta V, Willis M, Bennett JC, Robinson KA, Paudel K, Post DA and Marvanek S (2009) River modelling for Tasmania. Volume 4: the South Esk region. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Ling FLN, Gupta V, Willis M, Bennett JC, Robinson KA, Paudel K, Post DA and Marvanek S (2009) River modelling for Tasmania. Volume 5: the Derwent-South East region. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Post DA, Chiew FHS, Teng J, Vaze J, Yang A, Mpelasoka F, Smith I, Katzfey J, Marston F, Marvanek S, Kirono D, Nguyen K, Kent D, Donohue R, Li L and McVicar T (2009) Production of climate scenarios for Tasmania. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Viney NR, Post DA, Yang A, Willis M, Robinson KA, Bennett JC, Ling FLN and Marvanek S (2009) Rainfall-runoff modelling for Tasmania. A report to the Australian Government from the CSIRO Tasmania Sustainable Yields Project, CSIRO Water for a Healthy Country Flagship, Australia.

Enquiries

More information about the CSIRO Tasmania Sustainable Yields Project can be found at <www.csiro.au/partnerships/TasSY.html>. This information includes the full terms of reference for the project and all associated reporting products.

More information about the Water for the Future Plan of the Australian Government can be found at <www.environment.gov.au/water>.

Documents

River modelling for Tasmania Volume 3: the Pipers ......Hydro Tasmania Consulting: Fiona Ling, Mark Willis, James Bennett, Vila Gupta, Kim Robinson, Kiran Paudel and Keiran Jacka Sinclair