Supporting Queensland’s next generation of water modellers
The Queensland Water Modelling Network (QWMN) aims to improve the state’s capacity to model its surface water and groundwater resources and improve the quality of it’s models.
Established by the Queensland Government in 2017, the QWMN provides tools, information and collaborative platforms to support best-practice use of water models and the uptake of their results by policy makers and natural resource managers. The QWMN encourages engagement between modellers, researchers, policy makers and resource managers.
A key focus of the QWMN is building Queensland water sector capability through its mentoring program. The program partners experienced modellers with university undergraduate students and young water professionals interested in water modelling, it The aims to:
Grow the size and capabilities of the Queensland water modelling workforce by building a pipeline of skilled and enthusiastic graduates who want to pursue water modelling careers in Queensland.
Expose students to ‘real world’ water policy issues so that they develop applied knowledge and become enthused about the work of water modellers.
Develop undergraduate student critical analysis and systemic understanding of how the outputs from water models are and can be used.
The program has two components. Firstly, students undertake online water model training and tutorials to become familiar with the relevant models and tools. Students then undertake a ‘real world’ modelling challenge, supported by mentors who are experienced Queensland Government modellers.
eWater is an active supporter of the mentoring program, providing access to the full version of Source, training materials and technical support for participants.
Phase 1 of the program has been successfully completed by students from Griffith University, James Cook University, University of South Queensland, Queensland University of Technology and University of Queensland and a young professional within the Queensland Department of Natural Resources Mines and Energy (DNRME).
Students used eWater Source to understand how water quality targets are set for the Great Barrier Reef catchments. The Cattle Creek sub catchment within the Mackay/Whitsunday region used in the challenge. Through the project, participants both learn how to use Australia’s National Hydrological Modelling Platform, eWater Source and are exposed the the challenges faced by both government and industry to meet the Great Barrier Reef water quality targets.
The program has since been extended to students at the universities of Central Queensland and the Sunshine Coast in 2020-21. The QWMN is also working to engage modelling experts from the private sector.
Paddock to Reef – Integrated Monitoring, Modelling and Reporting Program
Targeting investment to improve the health of the Great Barrier Reef.
What is the Paddock to Reef program?
The Paddock to Reef Integrated Monitoring, Modelling and Reporting Program (Paddock to Reef program) started in 2009 as a joint initiative of the Australian and Queensland governments to report on water quality improvement resulting from investment in improved land management practices. Improving the quality of water leaving properties by reducing pollutant run-off is critical to build the health and resilience of the Great Barrier Reef (GBR). The program brings together industry bodies, government agencies, natural resource management bodies, landholders and research organisations.
The program provides a framework for evaluating and reporting progress towards the Reef 2050 Water Quality Improvement Plan targets. It integrates monitoring and modelling information on management practices, catchment indicators, catchment loads and the health of the Reef at the paddock, sub-catchment, catchment, regional and whole GBR scales (image below). The program evaluates management practice adoption, management practice effectiveness (in terms of water quality benefits and economic outcomes), catchment condition, pollutant run-off and marine condition.
How does Source support the program?
The catchment modelling for the program is based on the Source platform, with customised plug-ins developed by the Queensland Government to provide additional water quality functionality. A range of other purpose-built data collection and reporting tools have also been built to support the program. These include interactive maps to show pollutant generation rates and priority investment areas.
The models are primarily used to report on annual progress towards the reef water quality targets as a result of investment in improved land management practices. Model outputs are also used to determine priority areas for investment and to assess possible outcomes from different scenarios such as different rates of adoption of improved practices. The catchment models also provide inputs for the marine models.
Many of the actions required to achieve the water quality targets need to be undertaken by farmers and other land managers. To support greater uptake of the required actions, the Paddock to Reef program has been designed to share technical information in a way that can be easily understood and used. It also incorporates the local knowledge of land managers. Program features include:
Multiple lines of evidence to inform progress towards the targets.
Technical experts are based in the regions, giving them a good understanding of the local environment, issues and the effectiveness of management actions. This also helps build relationships with local land managers.
Ongoing refinement of the models and other tools to incorporate new knowledge, data and methods.
Results are presented online through an interactive reporting system to cater for the broad range of stakeholders interested in the results from the general public to scientific experts.
Data is made available to support other programs, for example regional report cards and regional natural resource management body and local government investment decisions.
‘Cut down’ models provide locally specific tools to assess individual projects and prioritise local investment.
Peer review, continual improvement and validation are critical elements for any modelling program. The Paddock to Reef catchment modelling program undertakes an external review every three years. The program is supported by a GBR-wide pollutant loads monitoring program which provides data to calibrate and validate the catchment models and increase confidence in the models over time.
This case study was prepared in collaboration with the Queensland Department of Environment and Science.
How Source supports the management of the Murray-Darling Basin
The Murray–Darling Basin is the largest and most complex river system in Australia. It runs through four States and one Territory and has a river network of 77,000 kilometres.
The Basin is home to more than 2.6 million people and has significant economic, cultural, social, and environmental values. Agriculture in the basin produces $24 billion annually, its waterways provide clean drinking water to 3 million people and its unique environment is home to 120 species of waterbirds and 46 species of native fish.
Modelling plays an important role in supporting the management of the Murray-Darling Basin. The need for a modelling platform that could be used across the basin’s diverse river systems was a key driver behind the National Hydrology Modelling Strategy. This case study highlights some of the ways Source models are used by the Murray-Darling Basin Authority (MDBA).
Water resource planning
The MDBA, in partnership with the River Murray States, have built a Source model to support water resource planning in the River Murray and lower Darling river systems. The Source Murray Model (SMM) is based on a daily timestep and includes:
flow routing and losses
irrigation, stock and domestic, town water supply and environmental demands
inter-state water sharing, allocation and ownership
definition of State Water access rights, allocation and accounting
water ordering and the operation of dams and infrastructure
The SMM allows the MDBA and Basin States to test policy and management options and observe the likely impacts changes may have on the system, such as possible changes to State water shares or the reliability of supply to water users, compliance with the Basin Plan or to manage river salinity levels. Options can be compared against four standard planning scenarios:
Without Development – removes consumptive diversions and regulating infrastructure (dams, weirs, offtake regulators etc.) to estimate what might have happened without regulation
Baseline Diversion Limit – represents the best estimate of conditions at June 2009, this scenario is used to define the Baseline conditions under the Murray-Darling Basin Plan (Basin Plan)
Current Conditions – represents the best estimate of the current management and operation of the Murray and lower Darling rivers
BSM2030 – represents the process used to calculate and maintain the salinity registers, which are central to the joint management of salinity in the River Murray system under the Basin Salinity Management 2030 strategy.
The MDBA is responsible for managing the River Murray and lower Darling rivers in accordance with a long-standing agreement between the Australian Government and the Basin states. As part of this, the MDBA implements water sharing arrangements, manages water infrastructure and delivers water to meet irrigation, stock and domestic, urban water supply and environmental demands.
To do this, the MDBA must understand:
how much water is in the systems dams
current and forecast river flows
inflows from tributaries, including water trade
how much water will be lost to evaporation and seepage
demand for water along the length of the river system
system constraints and operating rules
For many years the MDBA has used a spreadsheet model to support its river operations. Together with eWater, the MDBA has built a Source operations model to replace these spreadsheets. This source model is currently being tested before adoption. On completion of this testing, the model will give river operators a much more powerful management tool, allowing them to readily plan for operations under many different scenarios and to simulate the potential impacts of different operational decisions, on a daily and seasonal basis.
Environmental flow modelling
Over the last decade, significant volumes of water in the Murray-Darling Basin have been set aside for environmental purposes. Managing and delivering this water provides a range of new challenges for water managers.
The MDBA, Commonwealth Environmental Water Holder, then New South Wales Office of Environment and Heritage, Victorian Department of Environment, Lands, Water and Planning, and the South Australian Department for Environment and Water collaborated with eWater to better enhance environmental water modelling functionality in Source, through the:
environmental flow node – defines environmental flow demands based on a range of criteria, such as frequency, duration or magnitude of flows or event triggers
environmental water manager – to compare and prioritise different environmental demands, both spatially and temporally, subject to environmental water allocations.
This functionality allows river operators and environmental water managers to model different flow scenarios, to compare potential environmental benefits, understand the possible impacts on river operations and identify opportunities to boost environmental outcomes by combining with other water deliveries.
Large areas of the Basin are underlain by ancient marine sediments. Land clearing and water intensive farming has brought saline groundwater closer to the surface and into the river system. Increased water use has reduced river flows, resulting in less water to dilute the salt or flush it out to sea.
High salt levels can have serious implications for water quality, plant growth, land productivity, biodiversity, and the supply of water for human and animal needs. Managing the impacts of salinity is one of the most significant challenges in the Basin. Since the 1960s, governments and communities have worked to manage salt through improved land management practices and infrastructure. In 2015, the MDBA and Basin States launched the Basin Salinity Management 2030 strategy, which sets out how governments are working to address salinity and meet agreed targets.
Modelling underpinned the development of the strategy and will be a key part of its implementation. The SMM was used to understand baseline flows and to set agreed salinity targets. The model can also be used to test different management actions and how these might affect salt loads and salinity, and achieving the aims of the strategy. Using the SSM, baseline salt loads can be determined and to assess how these might be affected by different flow regimes or management actions. Figure 2 provides an example of the model outputs, it compares historic, current and benchmark salt loads.
This case study was prepared in collaboration with the Murray-Darling Basin Authority
Customising Source to manage blackwater risks
Construction of dams, weirs and use of water for irrigation, industry and towns has meant that many aquatic and floodplain ecosystems don’t get the water they did naturally.
One way of addressing this is to construct infrastructure, such as regulators and embankments that allow water managers to simulate natural watering regimes with lower flows.
While inundation brings a range of ecological benefits, it also has the potential to cause hypoxic blackwater (low dissolved oxygen) events. Blackwater events occur when inundation washes organic material from the floodplains into waterways leading to a rise in dissolved organic carbon in the water. This causes the water to turn a dark colour. The increased bacterial activity breaking down the carbon consumes oxygen, which causes a drop in levels of dissolved oxygen. In some circumstances, levels can drop so much that fish and other aquatic organisms do not have enough oxygen and die.
Blackwater can also create challenges for downstream water use, such as increasing treatment costs for drinking water supplies.
Blackwater events are a natural feature of many river systems. However, when natural flood patterns are changed and there are longer periods between overbank flows, the amount of organic material can be substantially increased, exacerbating the risk.
As part of the South Australian Riverland Floodplain Integrated Infrastructure Program (SARFIIP), the South Australian and Commonwealth governments have invested in major infrastructure upgrades to provide water to the Pike and Katarapko floodplains. The infrastructure allows the Department for the Environment and Water (DEW) to create higher water levels to inundate the wetlands, improving watering frequency and the ecological health of the floodplains.The project includes a number of initiatives to manage potential blackwater risks. This has included developing a model to help understand and predict dissolved oxygen responses to different inundation events, giving DEW important information to design watering events with reduced risk of blackwater events occurring.
Spreadsheet models were previously used to help understand blackwater risks (Howitt et al. 2007, Whitworth and Baldwin 2016, known as the Blackwater Risk Assessment Tool – BRAT). While effective for non-complex situations, DEW was unable to represent realistic hydrology, such as events where water flowed into and out of different floodplains along the river. A more sophisticated approach was required. DEW determined the best approach to be to develop a Source plugin to model blackwater processes on the floodplains.
DEW and the Murray-Darling Basin Authority use the Source modelling framework to help manage the River Murray System. The Source framework uses “plugins” as a flexible way to build additional modelling capability into model. Combined with the South Australian Source Murray Model, the new Blackwater plugin allows DEW to model interactions between the river and floodplains and the different processes that contribute to the risk of blackwater events.
Conceptually, the model is based on the original spreadsheet models and represents the key influences on the generation of blackwater events (from SMEC 2015):
time period since the last inundation
the duration and rate of inundation
water exchange during inundation
area of inundation
depth of inundation
influence of floodplain creeks on dilution
river dilution flows and proximity to environmental values
In addition, the model includes location specific information such as elevation, floodplain area and litter accumulation (from vegetation type), to understand the extent of inundation and litter accumulation.
The blackwater plugin is set up to represent all of the River Murray in South Australia, to consider interactions between the river and floodplains, as well as cumulative effects from multiple operations being inundated at the same time.
Model performance was tested in two ways. Firstly, simple floodplain scenarios were run through the Blackwater Risk Assessment Tool (BRAT) and the plugin. The results were comparable.
Secondly, a natural high flow event that inundated the Pike Floodplain in late 2016/early 2017 provided an opportunity to compare the model performance against observed DO data. The model compared well with the measured DO trends and magnitude but further testing under a wider range of scenarios is required to fully test the model. Notably, the event shows the importance of interactions with the river during blackwater events, as the majority of the DO decrease on the floodplain during Oct-Nov 2016 appears to relate to the low DO in the inflow water.
The model supports DEW to:
understand the potential DO changes associated with different environmental watering actions on the floodplains
adjust proposed watering actions to reduce the risk of blackwater events
forecast potential DO changes and blackwater risks from floods, and to identify potential river operations to minimise forecast blackwater events.
The figures below are two examples of the blackwater plugins outputs. The first shows the range of floodplain inundation under five different scenarios. The second shows forecast dissolved oxygen levels for each of the scenarios.
This work forms part of the $155 million South Australian Riverland Floodplains Integrated Infrastructure Program (SARFIIP) to improve the health and resilience of Riverland floodplains. SARFIIP is funded by the Australian Government through the Murray–Darling Basin Authority and implemented by DEW in partnership with SA Water.
The Blackwater Plugin was developed for DEW by the University of Adelaide and Flow Matters Pty Ltd. eWater was engaged by DEW to further develop functionality and modify the plugin to better work with improvements made to the Source platform after the plugin was developed.
Howitt JA, Baldwin DS, Rees GN and Williams JL (2007). Modelling blackwater: predicting water quality during flooding of lowland river forests. Ecological Modelling 203 (3–4):229–242. doi:10.1016/j.ecolmodel.20
SMEC (2015). SARFIIP Blackwater Risk Assessment: Stage 1. Report to the Department of Environment, Water and Natural Resources. SMEC, Adelaide in association with Natural Logic (Karla Billington) and University of Adelaide (Luke Mosley)
Whitworth KL, Baldwin DS (2016). Improving our capacity to manage hypoxic blackwater in lowland rivers: the Blackwater Risk Assessment Tool. Ecological Modelling 320, 292–298. 06.11.017
This case study was prepared in collaboration with the SA Department for Environment and Water and Murray-Darling Basin Authority.
Using Source for water and catchment management in the Australian Capital Territory
Source models support strategic planning, policy development, catchment and water resource management in the Australian Capital Territory
The models underpin the Australian Capital Territory (ACT) Water Strategy 2014-44 – Striking the Balance and support the ACT Government to meet its obligations under the Murray-Darling Basin Plan 2012.
Together with eWater, the ACT Environment, Planning and Sustainable Development Directorate (the Directorate) have embarked on a series of initiatives to upgrade the ACT’s Source models.
Audit of water models
The Directorate use several different Source models to inform strategic planning and decision-making regarding land use planning, urban development and climate change on water quantity and quality and the operation and maintenance of water infrastructure.
eWater was engaged to audit the Directorate’s existing Source models to ensure they were fit-for-purpose and could address emerging needs, including the ability to:
explore different policy, planning and management actions and assess potential impacts on the natural environment and water resources
predict impacts of land development decisions on water resources and assess mitigate measures
test new ways of operating water infrastructure
predict future environmental states to inform policy and management decisions, such as environmental condition and future water supply/catchment yields.
The audit identified several issues with the existing models that limited their ability to meet the current and future needs of the ACT Government. eWater recommended a substantial rebuild of the models, including:
Consolidating the existing nine models.
Utilising human-readable input sets and data sets to run scenarios, rather than individual models.
Reconfiguring storages and lakes in the catchment model to better represent how they operate.
Reconceptualising and recalibrating the rainfall-runoff models.
Incorporating the ACT water supply system.
Establishing a current conditions baseline case for scenario assessment.
Preparing and justifying a baseline scenario for the comparison of land use change scenarios.
Following on from the audit, eWater was engaged to rebuild the ACT’s catchment and planning models.
eWater built two new Source models for the ACT, a catchment and a planning model. Model performance has been improved by reducing the number of sub-catchments outside of the ACT. The new models use LASCAM (Large-Scale Catchment Model) rainfall-runoff models, allowing for physically based assessments of hydrological impacts of land use change. The catchment model now incorporates Canberra’s water supply system, including storages. The consolidation of the models allows for different policy and management options to be implemented by Scenario Input Sets.
In addition to the model re-build, the project also included collaborating with the ACT Office of the Chief Digital Officer to the integrate Source models with the ACT Government Water Data Management System. This brings two main benefits, it streamlines the transfer of data and model outputs and adds dashboarding capabilities to improve the presentation of model outputs. Integrations was achieved through a customised plug-in, developed by the eWater Software Development Team.
eWater also provided customised training to Directorate staff, to ensure they understood the Source model and were able to support its future development and application.
The Directorate is using the models to inform a wide range of water and catchment management activities, including to:
support investment in catchment remediation and
investment, by helping identify which areas will lead to the greatest
improvements in water quality and/or water yield
investigate Integrated Catchment Management
options across the ACT and the greater region
understand stormwater and flooding risks in
forecast future water supply and demand
compare likely outcomes from different water
investigate alternative water supply options,
such as treated effluent, grey water and stormwater for consumptive and
test different options to improve the management
of rivers and lakes, to promote recreational use and reduce risks to public
This case study was prepared in collaboration with the ACT Environment, Planning and Sustainable Development Directorate.
Melbourne Water – Improving water security with Integrated Water Resource Management
For 130 years Melbourne’s catchments and water infrastructure have provided for the water needs of Melbourne’s growing population and industry.
Population growth and climate change are putting increasing pressure on Melbourne’s traditional water supplies. Melbourne Water is working with retail water company customers to adopt a more integrated approach to delivering water services, with the aim of a city that is water sensitive, sustainable and liveable.
By adopting an Integrated Water Resource Management (IWRM) approach, Melbourne’s water companies are investing in a range of present or future innovative water management options, at the household, street, and suburb development scale, including:
recycling and reusing wastewater for things like agriculture, firefighting and dual-pipe systems that provide recycled water to homes and businesses for non-potable use like toilet flushing and watering gardens
recycling wastewater on site
capturing more stormwater for watering parks and sporting fields
refilling groundwater aquifers with stormwater or recycled water, for later extraction and use or to support natural environments
The IWRM approach requires a complete rethinking of the analysis of water system management. Traditional water system models are limited in their ability to analyse IWRM. Recognising this, Melbourne Water, with the support of eWater, has undertaken significant work to modernise their water resource models and to develop new tools to assess the benefits of IWRM.
A new approach to water resource modelling
Work has focused on three key areas:
upgrading the bulk water supply infrastructure (headworks) model
integration with local water supply and demand models
new tools for improving model performance.
Source Headworks Model
For the past 25 years, Melbourne Water has used the REALM (REsource ALlocation Model) Headworks System Simulation Model. The REALM model runs on a monthly time step and is used mostly for long-term water planning. Traditional monthly timestep water resource models like REALM focus on the behaviour of the centralized bulk water supply system and have limited ability to address emerging modelling needs, such as:
To what extent can small scale alternative water sources, such as greywater, recycled water or stormwater, be utilized?
What is the best mix of centralized and decentralized supply options?
How will water use change with different policy options or new approaches?
Where are the best locations for, or uses of decentralized systems?
How to leave more water for healthy river flows and reduce stormwater pollution ?
Working with eWater, Melbourne Water is in the process of replacing the REALM model with a Source model. The new model can run on both a monthly and a daily time step and includes headworks infrastructure and water supply catchments. Catchments have been added to give a better assessment of both the amount of water flowing into the reservoirs and the quality of that water. This will be important for understanding the impacts of changes in the catchment, for example after bushfires or how climate change might impact runoff and streamflows.
The monthly time step mode has been kept to support long-term water management decisions, with important improvements, including customised water allocation rules to determine allocations for primary entitlement holders, such as the water retailers and new optimization tools help assess operating strategies, to find the optimal trade-offs for different management objectives, such as cost and security of supply.
The daily time step mode supports Melbourne Water to manage environmental water in the regulated streams and to meet streamflow requirements in unregulated streams. It also facilitates smaller scale IWRM modelling and helps to better understand the potential risks to water quality. Importantly, the model has been designed to easily switch from a monthly and daily time step, allowing for better integration between short, medium and long-term operating plans.
Headworks models are designed to find the best way to meet water demands and inform the reliability of water supply. As such the representation of demands in the model is equally as important as the representation of water supplies. An innovative feature of the new model is the incorporation of spatial geographic data to better understand demand. Spatial data includes population data, dwelling types and land-use. Ultimately, it will help estimate changing water demand and the potential impact of alternate water supplies at the suburb scale.
Urban Developer in Source
The upgrades to the headworks model bring a wealth of new features to support IWRM but they do not fully take into account potential alternative water supplies, such as rainwater, stormwater and wastewater, or localized demands. A second component of the project has been to incorporate eWater’s Urban Developer tools into the Source platform. This allows local small scale water sources and demands to be considered in the context of overall large scale supply options.
Urban Developer can now estimate urban water demands based on a suburb’s characteristics and how they might change, for example with population growth, dwelling type, the adoption of Water Sensitive Urban Design approaches or alternative water supplies like rainwater tanks. The approach was tested across four catchments and the model calibrated for the Melbourne region. The Urban Developer plugin to Source was developed to feed the outputs of the Urban Developer demand model into the Source Headworks Model.
An important aspect of the work was looking for more sophisticated ways to estimate demand and to differentiate between indoor/outdoor water use, and commercial and industrial water use. For example, we can now test if including information on household income or lot size provides more accurate water use estimates.
Improving model performance
Running large, complex models for different scenarios takes a lot of computing power and time. Melbourne Water uses optimization tools to inform water resource decisions by assessing how to maximise the reliability of supply and reduce delivery costs. With the enhanced model functionality, it would take a month to process Melbourne Water’s optmisation runs on a standard computer, even longer if new requirements, such as environmental flow delivery and integrated demand management options were included.
Working with eWater, a cloud-based run manager was set up to enable large numbers of simulations to be run across hundreds of virtual machines. A common web browser interface gives access to different run locations, including a local (single PC) and the Cloud (hundreds of virtual machines). Run times have been reduced to a number of hours.
In addition to saving time, the system is easy to install and use, does not require specialist knowledge and reduces the costs associated with owning and maintaining significant amounts of hardware. A particular advantage is that jobs can be tested locally before launching on the cloud, reducing the risk of minor errors negating the final results and the modellers can continue working on other projects while the simulation is being run.
Following the initial success, work is underway to expand the type of jobs that can be run on the cloud and to make Source and the optimisation tool, Insight, more cloud friendly.
The project has delivered significant improvements to Melbourne Water’s modelling tools. Innovative projects like these require flexibility, new ways of thinking and a high degree of collaboration. eWater and Melbourne Water have worked closely together throughout the process, proposing and testing different methods, refining and adapting along the way. A key aspect was including Melbourne Water in the software development process and allowing them to work directly with eWater to scope and prioritise software improvements.