While water is a critical resource for the economic and social sustainability of the nation, the sustainable supply of river water itself is dependent on the ecological balance between environmental flow and desirable allocations at all points from source to termination.
The National Water Initiative “aims to strike a balance between the consumption use of water and environmental health.”
It is intended, in its maturity, this will be a flagship environmental project born in a sense of balanced and responsible decision making, highlighting:
– sustainable healthy rivers.
– water services to Australian inland communities, industries, environmentally aligned enterprises, research and development.
– a river based wildlife corridor stretching the length of Australia – featuring native riparian plantings.
– healthy connected wetlands.
– river aligned carbon farming and sequestration programs.
– communities (farming and townsfolk) engaged in local water resource management and monitoring, rewarded as guardians of the resource and the landscape.
– water plans specific to identified outcomes in individual catchments.
– water dependent industries contributing to the whole and engaged in carbon off-setting.
There is an emerging view in the scientific community, if we remove more than 66% of the natural flow from rivers we will cause obvious and significant damage to river health
Through this preliminary study we intend to test the following environmental criteria and ideals:
(1) Extraction from any river source not to exceed 25% of monsoon season delivery ensuring environmental flow to the river/s is assured, including estuarine and near shore marine systems. To this end each river catchment should be considered and managed as a single resource with planning based on hydrological boundaries.
Early indications are, there is significant safety margin in current extractions from rivers both east and west of the Great Dividing Range to accommodate our proposals (current water allocations from Gulf rivers are noted to be less than 1%).
(2) To design a scheme having no apparent impact on the Great Barrier Reef or Gulf of Carpentaria fishing industry.
(3) Control of water near the source to ensure a release regime geared to seasonal cropping needs, native fish breeding cycles, wetland replenishment for migrating birds, vegetation needs along flood plains and minimal impact on river structure and biodiversity. Intermediate detention holdings may assist this function.
(4) Creation of a network of limited impact / smaller footprint dams located west of the Great Dividing Range, harnessing a percentage of surface run-off for injection into chosen storage aquifers. These dams to be spread across various catchments and therefore varying climatic events, drawing smaller volumes of water from any one location while safeguarding the environmental flow at the source.
(5) Extraction from aquifers chosen for storage will not diminish the natural level of the aquifer during dry seasons or impact adversely on dependent spring fed systems.
(6) Water supply and allocations will be provided in a manner guaranteeing environmental flow to inland rivers within the system. Base line and historic monitoring of river health and environmental flow is imperative.
(7) Water will be stored near the source in such a manner to control regulated reliable flow while minimising river impact during normal delivery and also natural flood and weather events.
(8) Water storage impact on existing quality farming lands is to be minimised.
(9) Evaporation of both storage and moving water will be considered and minimised as a commitment to resource management efficiency.
(10) Primary water courses will be profiled and audited in an effort to quantify the projected allocations of water in the system, environmental flows, evaporation rates or other natural losses. This will assist in resolving the desired allocation levels and supply limits at the source, so avoiding the conflicts now apparent in the Murray Darling Basin.
(11) Possible cultural sites and species at risk are to be identified.
(12) Wetlands of national and international (Ramsar) interest are to be identified.
(13) Channel construction will be needed to connect rivers and agricultural hubs in the system and as a means of filtering inter-basin feral species transfers (Cane toads and Tilapia fish having already reached SE and SW Queensland waters).
Also to be identified in the study are the likely impacts relating to construction, any downstream, surface or ground water impacts, flooding regimes, existing degradation or environmental issues that might be rectified by the project, possible flood mitigation solutions in the form of temporary detention holdings on public lands prior to re-release of waters to the river system.