Tumut
Indicator: Groundwater
Results for this indicator are also available for [an error occurred while processing this directive]
What the results tell us for Tumut
Groundwater in the Tumut Shire is of moderate quality (DLWC 1999), with a steadily decreasing water table (DWE 2008). Groundwater quality is not considered suitable for human consumption, but can be used for some livestock, domestic and limited industrial uses without treatment.
Groundwater supplies
Groundwater flow in the Shire is mostly from local/intermediate flow systems in a variable geological environment consisting of sedimentary, intrusive and extrusive Palaeozoic rock (DPI 1998). Bore hydrograph data indicates a consistent seasonally adjusted drop in water levels for the reporting period 2004 to 2008, continuing a trend observed since 1991. A low natural rainfall is likely to be the most significant factor which is further compounded by an increase in extraction (Beale et al. 2004).
Groundwater use
Total groundwater extraction in the Tumut Shire is less than 10 GL/yr compared with a natural recharge of more than 500 GL/yr (AWR 2000). This is considered a low level of extraction (extraction is 0 to 29% of recharge), and sustainable for the entire Shire. The Department of Water and Energy has rated the threat to groundwater as generally low. An exception to this is the immediate area around Tumut township, and the north-east region of the Shire where groundwater quality is considered at threat (DLWC 2001). Tumut Shire Council does not extract groundwater as part of its water supply.
The State Water Corporation (SWC), on behalf of the Department of Water and Energy, (DWE) administers much of the water allocation in rural NSW. To recover the cost of administration, infrastructure and future investment SWC charges each licensed user a base charge, either $51.46 for non-monitored or $118.56 for monitored areas plus a per megalitre access charge. As part of the Murrumbidgee groundwater area, Tumut is charged a $1.03/ML access charge and $0.51/ML usage charge. Although base charges are consistent throughout the state, access and usage charges are the lowest in the state (SWC 2008).
Groundwater quality
Groundwater salinity in Tumut Shire is moderate (1,000-3,000 mg\L) (DLWC 1999) with little variation throughout the region. Water is considered suitable for livestock and limited domestic and industrial use only. Groundwater in the area is unsuitable for human consumption without treatment.
A project of significance to the local region was the Urban Salinity project. This was funded by the Murrumbidgee Catchment Management Authority which saw the installation of 10 bores in Tumut and three in Adelong to measure the extent of salinity found in urban areas groundwater. Monthly samples were analysed from December 2006 up til March 2007 at each site when water was available. The results demonstrated that the region involved in the project had no issue with salinity. As groundwater levels were also recorded we also have this data for the period December 2006 - March 2007 for the sites chosen for the sampling bores.
Managing groundwater demand
Water conservation measures
Tumut Shire is covered by the Murrumbidgee Catchment Management Authority (MCMA). The CMA was established to guarantee the protection and sustainable development with in its area of administration, including impact on water quality and use. At the time of writing, the MCMA’s Action Plan was not readily available for reporting on the CMA’s water management targets in the Tumut Shire (MCMA 2007).
Laws and policy
Outside of regional CMA policies, the use and treatment of groundwater is generally the same throughout New South Wales (NSW). Specifically water management and use in the Gundagai Shire is covered under:
- NSW Water Extraction Monitoring Policy (2007): Designed to increase the extent of active monitoring of water extraction to cover 90% of the total volume of water extracted for each water sharing plan.
- NSW Water Extraction Monitoring Standards (2005): Designed to increase the quality of groundwater extraction monitoring.
- National Water Initiative (2004): NSW is a party to the National Water Initiative (NWI), a national initiative to coordinated Australia's water supply to guarantee the greatest possible social, economic, and environmental benefits.
- NSW NWI Implementation Plan: Addresses the initiatives set out in the NWI specific to the State of NSW.
- Living Murray and Snowy Initiatives (2002): Initiative between Federal and State governments concerned predominately with surface water, however, may indirectly impact on groundwater.
- Water Management Act 2000 (NSW): Aim is to protect the supply of water to the environment and water users. Its introduction has been gradual and once fully implemented will largely supersede the Water Act 1912.
- NSW Groundwater Quality Protection Policy (1998): Aim is largely to protect groundwater resources against pollution.
- Local Government Act 1993(NSW): Covers the quality of water supplied for human consumption by local Shire Council, including groundwater as a source.
- Water Act 1912 (NSW): Largely superseded by the Water Management Act 2000 but some provisions still apply.
- Australian Constitution (1901): Section 100 of the Constitution outlines the States primacy over the Commonwealth in terms of laws and regulations affecting the use and conservation of water.
About the data
Data was supplied by Tumut Shire Council and DWE. Threshold salinity values of 800 µS/cm and 1,600 µS/cm were used for water quality assessment. They represent the maximum desirable water standard set by the World Health Organisation for human consumption (800 µS/cm) and a threshold at which adverse environmental changes can be expected (1,600 µS/cm) (NHMRC and ARMCANZ 1996).
Groundwater with less than 1,000 mg of salt per litre is also considered good quality and suitable for drinking water and most uses; groundwater with 1,000–3,000 mg of salt per litre is considered fair to poor and suitable for livestock, some domestic and limited industrial uses (DLWC 1999).
mg/L = milligrams per litre
References
Australian Water Resources (2000) National Land and Water Audit.
Beale G, Miller M, Barnett P, Summerell G, Gilmore R and Hoey D (2004) NSW Coastal Salinity Audit, Department of Infrastructure Planning and Natural Resources, Sydney, online at http://www.dnr.nsw.gov.au/salinity/science/pdf/coastal_audit1.pdf.
Department of Land and Water Conservation (NSW) (1999) Groundwater Quality Protection Policy, Department of land and Water Conservation, Sydney, on line at http://www.dnr.nsw.gov.au/water/pdf/nsw_state_groundwater_quality_policy.pdf.
Department of Land and Water Conservation (NSW) (2001) Groundwater Vulnerability Map and Explanatory Notes, Department of Land and Water Conservation, Sydney, on line at http://www.dnr.nsw.gov.au/water/pdf/lachlan_vulnerability_map.pdf.
Department of Primary Industries (NSW (1998) Geological Map of New South Wales (1:250000 scale)
Department of Water and Energy (NSW (2006) 2005/06 Water Supply and Sewage Benchmarking Report on line http://www.deus.nsw.gov.au/Publications/dwe_nsw_water_supply_and_sewerage_
benchmarking_report_2005-06.pdf
Department of Water and Energy (NSW (2008) – Bore Location Information supplied in GIS format.
DLWC - see Department of Land and Water Conservation
DWE - see Department of Water and Energy
Murrumbidgee Catchment Management Authority (NSW) (2007) SRCMA Annual Report 2006/2007 online at
http://www.murrumbidgee.cma.nsw.gov.au/uploads/media/Annual_Report_06-07_Section_1_01.pdf
NHMRC and ARMCANZ (1996) Australian Drinking Water Standards, National Health and Medical Research Shire Council & Agricultural Resources Management Shire Council of Australia and New Zealand, Canberra.
State Water Corporation (NSW) (2008) Water Management Charges for Licensed Water Users on line http://www.statewater.com.au/watdel/water_mgt_charges_for_licensed_water_20080124.pdf
Tumut Shire Council 2007 (NSW) (2007) Annual Report, online at
http://www.tumut.nsw.gov.au/
