The water and wetlands assets as referred to in the Regional NRM Plan include the surface water and ground water systems, and artificial waters. Floodplain management is not included in this section as it is considered in within the ‘Land and Soils’ section of the Plan.
A key concept which underpins all considerations of water assets in this Plan, is the acknowledgement of the connectivity of surface water and ground water systems and wetlands and artificial waters within the landscape. This connectivity includes production systems, ecological systems, infrastructure and people.
For management and planning purposes the asset is divided into the sub-themes of:
- water – being the quantity and distribution of H2O across and underneath the region, and
- wetlands – being the riverine and non-riverine systems dependant on water (quantity) but also on other habitat features such as water quality, shelter, nutrients, fish passage, weeds and pests.
Water is an issue of great importance and controversy to the NRM Plan area. The NRM Plan area is reliant on the continued capacity and quality of water resources to sustain and enhance social and economic wellbeing, as well as providing environmental stability and health. Management of water harvesting/extraction and use is critically important for the health of our aquifers and water systems. Ensuring that adequate water remains in aquifers and enters water systems is vital to ensuring long term economic and environmental viability (QMDC 2004).
There has long been an awareness of the need to manage water diversions from natural flow systems for ongoing benefit of human needs, agriculture, industry and environmental needs. Historically this was managed by state governments based on the constitutional rights vested in water resting within each state. However, with evolving realisation of the impact of diversions for human and agricultural use on downstream users and systems, increasing levels of interstate dialogue have been undertaken. A key outcome of such dialogue was the 2005 ‘Cap on diversions’ in the Murray-Darling Basin agreed to by all state governments. For Queensland this required ongoing Water Resource Planning under state legislation to comply with the Cap stipulation:
“Long term diversion cap for Queensland – The Government of Queensland must ensure that diversions from each designated river valley in Queensland does not exceed diversions under baseline conditions in that designated river valley.” (MDBC 1995; MDBA 2012b)
Within the confines of this Cap and guided by the Queensland Water Act 2000, Water Resource Plans and associated Resource Operations Plans (QDNRM 2013a) have been developed for the parts of the Condamine and Balonne (QDNRM 2004), Moonie (QDNRM 2014) and Border Rivers (QDNRM 2003) catchments that lie in Queensland. (It should be noted that as a community-based, not-for-profit, QMDC does not have a role in the setting of water-use limits. QMDC is focussed on the sustainable use of resources and works with stakeholders to achieve that goal.)
One of the most valuable attributes of groundwater is that it can usually be relied upon during periods of drought when surface water is limited or non-existent. Consequently, groundwater has been heavily relied upon by urban communities, grazing enterprises, intensive livestock holdings, industrial, mining and the irrigation sector(QMDC 2004).
In terms of significance of groundwater storage volumes, the Great Artesian Basin (GAB) aquifers that underlie the vast majority of the Queensland Murray-Darling Basin are in a class of their own. Their availability for development has been tempered over time by the inherent costs associated with establishing a controlled bore into pressure aquifers at depths in excess of a thousand metres and temperatures up to 100°C. A common feature of GAB aquifers is a tendency for high levels of sodium bicarbonate making the water unsuitable for irrigation. While GAB aquifers have significant storage by virtue of their size (area and thickness), recharge is quite limited (QMDC 2004).
Groundwater aquifer systems of any significance in the region in terms of quantity and quality may be categorised according to their geological association. These being:
- unconsolidated aquifers associated with alluvial deposits, and
- consolidated sedimentary aquifers associated with the GAB (QMDC 2004).
Diversions in the unconsolidated aquifers are managed through the Water Resource Plans while GAB waters are managed under a separate multijurisdictional Water Resource Plan. This GAB Plan aims to ensure sustainable levels of take to secure future water access for towns and agriculture as well as for Groundwater Dependant Ecosystems (QDNRM 2006).
Healthy systems are essential to meet both community and ecosystem demands on the region’s water environments. This is established in many historic documents and collated in the 2004 version of this Plan (Rivers Floodplains and Wetlands section) and in the Draft Environmental Values and Community Consultation Report (QMDC 2012a).
The majority of the Queensland Murray-Darling Basin lies in Australia’s subtropical climate zone with only the New England Tablelands in the Condamine-Balonne and Border Rivers catchments experiencing a temperate climate. There is a general east-west decline in annual rainfall and an increase in rainfall variability. The topography of the Plan region as a whole is generally very flat. The average elevation of river channels in the region is about 250 metres above sea level, and the average slope of river channels is very low, at about 0.5 metres per kilometre. This low slope results in a relatively slow movement of water down river channels, allowing the accumulation of fine sediments. Most of the waterways of the region are naturally turbid (Fielder et al. 2011a).
In the NRM Plan a list of threats to aquatic ecosystems was developed and these included direct threats of:
- nutrients, pesticides, sedimentation and suspended solids, gross pollutants,
- cultivation, grazing, unstable banks, sand and gravel extraction,
- shallow groundwater, salinity,
- cleared vegetation,
- changed flow regime.
The NRM Plan also lists associated threats due to community capacity including:
- capacity to change to sustainable practices, and
- lack of riparian management and water quality knowledge and information (QMDC 2004).
In the QMDC Regional Caring for Country Plan 2008-2011, Traditional Owner Group representatives in the region indicated that “the waterways, rivers and riparian zones of the region are considered to be the lifeblood of Country” (QMDC 2008). Furthermore this group identified the following existing or potential environmental issues relating to aquatic ecosystems more broadly:
- declining river health including native fish populations due to increasing carp,
- contamination of water, rubbish along banks, dams and weirs, sand dredging/extraction,
- poor water management resulting from high volumes of water used for irrigation, water stealing, open bore drains, high underground water usage, illegal dams, sleeper licences, water trade,
- clearing of native vegetation, loss of habitat and biodiversity along river networks,
- pest and weed control within river systems and other wetlands,
- soil erosion increasing stream sediment loads, and
- increased salinity levels reducing water quality standards.
Traditional Owner Groups also identified the community and cultural issues of:
- inappropriate location of reserves and picnic areas for tourists,
- loss of traditional medicines and food,
- lack of access to rivers, and
- the need for an Indigenous allocation of water, or monetary compensation (QMDC 2008).
Coal and coal seam gas pollutant and aquifer integrity issues have emerged since the 2004 NRM Plan version but were discussed at length in consultation meetings and in feedback from community consultation on the QMDC Mining Policy (Fletcher et al. 2011).