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River Science

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Background
The backbone of sound environmental management is quality information (data). Smartrivers’ believed that the information available at the time the Draft WAMP was being prepared was very poor and any Government decisions based upon it would carry a high level of risk of being wrong. This applied to both hydrology and ecology. Smartrivers undertook reviews of the hydrology and, as no single Government department was responsible for all aspects of river monitoring, Smartrivers decided to undertake their own ecological data collection program.

Hydrology

Smartrivers commissioned Dr John Porter, initially to review the existing hydrological data, and later to review the Integrated Quantity and Quality Model or IQQM. The IQQM is a flow model that looks at how much water is making its way through the river and channels and what water leaves the system. The information gained for the IQQM is vital in the water management decision making process.

Dr Porter concluded that gauging errors related to flood flows resulted in an underestimation of total flow by between 15 and 30%. The report was independently reviewed by Prof Tom McMahon of Melbourne University and Prof McMahon agreed with the finding, suggesting that DNRM needed to adjust their rating curves.

Dr Porter also reported that the IQQM program as it was established for the catchment, contained a number of one-way errors which, when added together, resulted in a significant overestimation of the effect of water extraction on flows within the system.

Ecological Monitoring Program

This program is conducted by Dr Lee Benson of EM (Ecology Management) Pty Ltd. The program aims to sample aspects of the physical, chemical and biological environments at sufficient sites throughout our region to allow us to understand the condition of our rivers and wetlands. The program is entirely funded by Smartrivers and represents:
- the first time that such a broad range of measures have been sampled at each site on each sampling occasion;
- the first time that each river in the region was sampled concurrently and at more than one site;
- the first time that multiple reference sites on adjacent rivers were sampled concurrently;
- the first time the wetlands of the region had been included in a sampling program; and,
- the first time that both the methods and results were independently peer reviewed before reports were released.

Sampling has been conducted many times to date, with two occasions timed to coincide with similar sampling being conducted by DNRM. Future sampling will depend on flows in the river and funding support.

Results
The report of the Technical Advisory Panel (TAP) to the WAMP process claimed that the aquatic environment of the Lower Balonne was severely degraded and that this was a result of water resource development. The Smartrivers program has not supported either part of that conclusion.

The conflicting views were tested in court in the Anchorage V DNRM case in June 2001 and comments by key DNRM witnesses confirmed that the original conclusions of the TAP were incorrect. This is unfortunate because those conclusions have been used as the foundation of many other reports since, including those of the National Competition Council.

All the various data has recently been rigorously reviewed and analysed by an expert panel, chaired by Professor Peter Cullen. The final report finds that the aquatic invertebrates in the river do not at present indicate evidence of human disturbance either moving downstream, or in comparison to adjacent catchments. The Cullen Report when on to find that the rivers and wetlands of the Lower Balonne system are presenting in a reasonable ecological condition.

All the monitoring reports produced to date are available from the library.

Testing the AusRivAS Method
The AusRivAS method of sampling macro invertebrates (bugs) within rivers had been a key component of DNRM’s environmental assessments. This method is generally thought to be suited to broad scale assessments, but because the Smartrivers program was at sub-catchment scale, Dr Benson felt a different method may be more suitable.

Smartrivers funded a detailed experiment which compared the unreplicated qualitative AusRivAS approach with a replicated quantitative approach. The results supported the use of the latter so the Smartrivers program now uses replicated surber samples in the edge habitat. Peer review of the experiment by Dr Bruce Chessman, Principal Aquatic Scientist with the Department of Land and Water Conservation in NSW, supported the result.

Risk Assessment
Smartrivers believes that our aquatic environments should be managed holistically, that is, there is little point managing the volume of water we extract if the cause of any problems is more related to land clearing, or salinity, or some other factor. Smartrivers commissioned Dr Benson to produce a major Risk Assessment report.

The report concluded that land clearing and land use had caused changes to the landscape and waterways, particularly with respect to sedimentation and water quality. To date, impacts of water resource development related to the construction of weirs, dams and levees and there was a significant future potential risk related to the volume of water which irrigators could now extract. The level of risk could not be quantified because the hydrology of the system was not well understood or accurately modelled.

The Future
Smartrivers agrees with Dr Benson’s conclusions regarding risks. We are now investigating ways to address those risks and move toward sustainability. Some risks relate to causes we can address ourselves, while others are catchment related or are the sole responsibility of others. As such, Smartrivers seeks the cooperation of Government at all levels and aims to work with existing catchment management related groups in reducing risks to our aquatic environments.

The Lower Balonne is naturally a highly variable system, a typically Australian boom and bust, flood and drought system. Smartrivers believes that the standard of scientific work we have commenced and funded must continue over an extended period if we are to be confident in our decisions regarding environmental management. We must be able to judge if we are moving in the right direction or if we need to do more. Critical to this ability is the accurate gauging of flood flows.

Good quality science is not cheap and Smartrivers seeks the support of Government and stakeholders, perhaps through commitments under the Resource Operations Plan or the National Action Plan for Salinity and Water Quality, to continue the monitoring program.

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