Groundwater is the water beneath the earth's surface which filters through and is held in rock, gravel or sand. Groundwater can be found in all areas of NSW, although its quantity and quality vary widely. An aquifer is a geological formation such as permeable rock or unconsolidated material (gravel, sand silt or clay known as alluvium) which can hold groundwater.
An important natural resource in NSW, groundwater is a source of drinking water for many rural towns and is used for industrial needs such as mining. It also supports the domestic and stock requirements of farms or remote households and communities, and can be used for irrigation. While water availability in a river can change very quickly because of rainfall or dry conditions, groundwater availability is more stable.
Groundwater is most commonly accessed by bores or wells. Of all water use in NSW, 11 per cent is sourced from groundwater. The Office of Water is responsible for the management of groundwater resources in NSW.
Until relatively recently, management of the state's groundwater resources was generally focused on investigation and subsequent development. Little attention was paid to the impacts that extraction might have on its continuing availability and the possible impacts on the environment.
The NSW State Groundwater Policy Framework Document (PDF 2 MB) highlights the need to manage the access to groundwater within the sustainable yield of a system so that the availability of the resource is sustained for all consumptive uses as well as the dependent ecological processes. Sustainable groundwater management also requires the protection of water quality and groundwater dependent ecosystems.
Most groundwater in NSW is sourced from groundwater systems covered by water sharing plans. Partly or fully buried groundwater sources have little or no surface expression (outcrop), and therefore have very little or no water available for extraction based on rainfall recharge. The NSW policy for managing access to buried groundwater sources (PDF 2 MB) presents a framework for allowing access to a small percentage of groundwater storage in specified porous rock groundwater sources, subject to certain criteria being met.
Groundwater trading rules are established by the relevant water sharing plan in areas covered by the Water Management Act 2000. For access to new licences for groundwater in areas still under the Water Act 1912, a licence application under may be lodged, subject to any embargo order applying to that area.
- For information on applying for a transfer in areas under the Water Act 1912, visit Licensing under the Water Act 1912
- More information on Groundwater licences under the Water Act 1912 – Frequently asked questions
- More information on Embargo orders applying to groundwater outside water sharing plan areas in NSW.
The NSW Office of Water undertakes drilling to investigate the states' groundwater resources. The Office of water has more than 3000 monitoring bores and uses computer-based groundwater modelling to better understand groundwater flow systems.
Broken Hill groundwater bore drilling project and town water supply
The NSW Government is making provisions for further water supply by establishing a groundwater program to be used only when there is insufficient surface water.
The NSW Office of Water will continue undertaking a groundwater investigation to find water to secure an 'emergency town water supply' for Broken Hill to be used during times when there is insufficient surface water to meet that need.
- Broken Hill-Menindee Groundwater Bore Drilling Project - Update 5 (PDF, 234.49 KB)
- Securing an emergency town water supply for Broken Hill (PDF 49 KB)
- Broken Hill Water Supply Investigations. Groundwater bore investigations - review of environmental factors (PDF 8.3 MB)
- Broken Hill-Menindee Groundwater Bore Drilling Project (PDF 366 KB)
- Broken Hill-Menindee Groundwater Bore Drilling Project - Update 2 (PDF 132 KB)
- Broken Hill-Menindee Groundwater Bore Drilling Project - Update 3 (PDF 131 KB)
- Broken Hill-Menindee Groundwater Bore Drilling Project - Update 4 (PDF 131 KB)
Expanding our networks
The Office of Water is increasing the spatial coverage of our monitoring bore network through the drilling of new groundwater bores in key areas of NSW between August 2013 and August 2014. The three areas of construction are Gunnedah to Spring Ridge, Broke-Bulga and Merriwa. Download the factsheets below for more information:
- Groundwater Monitoring Bore Drilling Project at Narrabri: Review of Environmental Factors Addendum (PDF, 2641.16 KB)
- Groundwater Monitoring Bore Drilling Project at Narrabri: Review of Environmental Factors Addendum Appendix A - Biodiversity Assessment
(PDF, 3222.93 KB)
- Groundwater Monitoring Bore Drilling Project at Gloucester: Review of Environmental Factors (PDF 5.39 MB)
- Coal Seam Gas Groundwater Monitoring Bore Drilling Project: Gloucester and Narrabri (PDF 42 KB)
- Groundwater Monitoring Bore Drilling Project: Broke-Bulga (PDF 709 KB)
- Groundwater Monitoring Bore Drilling Project: Broke: Review of Environmental Factors (PDF 4.65 MB)
- Groundwater Monitoring Bore Drilling Project: Gloucester (PDF 392 KB)
- Groundwater Monitoring Bore Drilling Project: Gunnedah to Spring Ridge (PDF 702 KB)
- Groundwater Monitoring Bore Drilling Project: Gunnedah to Spring Ridge: Review of Environmental Factors (PDF 8.36 MB)
- Groundwater Monitoring Bore Drilling Project: Merriwa (PDF 378 KB)
- Groundwater Monitoring Bore Drilling Project: Merriwa: Review of Environmental Factors (PDF 4.23 MB)
- Groundwater Monitoring Bore Drilling Project: Merriwa: Review of Environmental Factors: Addendum (PDF 962 KB)
- Groundwater Monitoring Bore Drilling Project: Narrabri (PDF 242 KB)
- Groundwater Monitoring Bore Drilling Project: Narrabri: Review of Environmental Factors (PDF 1.2 MB)
- Groundwater Monitoring Bore Drilling Project: Narrabri: Review of Environmental Factors: Appendix B (PDF 4.1 MB)
As of May 2014, the NSW Office of Water has completed six new monitoring bores, with four in the Broke-Bulga area and two west of Gunnedah. The drilling at Broke-Bulga is complete with groundwater monitoring bore fixtures yet to be installed. West of Gunnedah, two deep monitoring bores have been completed and the Office of Water's drilling rig has now moved south of Gunnedah to the Spring Ridge area where work is ongoing. In addition, a second drilling rig will be mobilised to the Merriwa area in May 2014, where a monitoring bore is to be drilled.
NSW groundwater work details provide preformatted reports (borehole logs) containing information about licensed water bores, wells and excavations. Please note there is a slight delay while this application is loading.
For information about obtaining a licence for a groundwater works (licensed water bores, wells and excavations) please go to Licensing under the Water Act 1912.
The Office of Water is producing a series of status reports on the state's groundwater resources. These reports describe the physical state of the resources for different areas, provide information on groundwater licensing and use, and discuss the response of the groundwater system to variability in groundwater use and rainfall.
- NSW Border Rivers Alluvial Groundwater Sources - Groundwater Status Report 2015 (PDF, 1791.5 KB)
- Billabong Creek Alluvium - Groundwater Status Report 2012 - Groundwater Management Area 014 (PDF 6 MB)
- Lower Gwydir Groundwater Source: Groundwater Management Area 004. Groundwater Status Report – 2008 (PDF 1.7 MB)
- Lower Murray Alluvium: Groundwater Management Area 016 – Groundwater Status Report 2010 (PDF 3 MB)
- Lower Murrumbidgee Groundwater Sources: Groundwater Management Area 002. Groundwater Status Report – 2009 (PDF 4.6 MB)
- Lower Namoi Groundwater Source Groundwater Management Area 001. Groundwater Status Report – 2008 (PDF 2 MB)
- Mid Murrumbidgee Alluvium: Groundwater Management Area 013. Gundagai to Narrandera. Groundwater Resources Status Report 2007 (PDF 2 MB)
- Peel Valley Catchment Groundwater Status Report 2010 (PDF 1.9 MB)
- Upper Lachlan Alluvium – Groundwater Management Area 011. Groundwater Status Report – 2010 (PDF 2 MB)
- Upper Macquarie Alluvium: Groundwater Management Area 009. Groundwater Status Report – 2010 (PDF 4.2 MB)
- Upper Murray Alluvium: Groundwater Management Area 015. Albury to Corowa. Groundwater Resources Status Report 2008 (PDF 1 MB)
- Upper Namoi Groundwater Source – Status Report 2011 (PDF 6 MB)
- Western Murray Porous Rock and Lower Darling Alluvium Groundwater Sources - Groundwater Status Report 2011 (PDF 3 MB)
- Young Granite Groundwater Source - Status Report 2012 (PDF 3.8 MB)
The Office of Water is producing a series of annual summary reports on the state's groundwater sources describing water sharing plan provisions, available water determinations, account management rules and groundwater trading. These reports will include up to date information on access licences, water account information, trade statistics, groundwater extractions and water levels.
- Lower Lachlan groundwater source summary report 2008-2015 (PDF, 512.17 KB)
- Lower Gwydir groundwater source summary report 2006-2015 (PDF 750 KB)
- Upper Namoi Zone 3 groundwater source summary report 2006-2015 (PDF 635 KB)
- Upper Namoi Zone 2 groundwater source summary report 2006-2015 (PDF 454 KB)
- Upper Namoi Zone 5 groundwater sources summary report 2006-2015 (PDF 1.1 MB)
- Lower Murray groundwater sources summary report 2006-2014 (PDF 1.1 MB)
- Upper Lachlan groundwater sources summary report 2012-2015 (PDF 1.3 MB)
- Lower Murrumbidgee groundwater sources summary report 2006-2014 (PDF 1.4 MB)
- Lower Namoi groundwater sources summary report 2006-2013 (PDF 812 KB)
The Office of Water undertakes risk assessments following the implementation of a water sharing plan.
- Lower Murrumbidgee Groundwater Sources – Resource condition assessment report – 2010 (PDF 2 MB)
- Upper Namoi Groundwater Sources – Resource condition assessment report – 2010 (PDF 3.4 MB)
These reports provide information on trade assessment rules, established local impact areas and in-house tools developed to manage groundwater extractions at a local level.
- Groundwater trading and management of local impacts report – Lower Murrumbidgee Deep Groundwater Source (PDF 2.1 MB)
The NSW Office of Water has undertaken an assessment of the possible causes of water level decline reported for Thirlmere Lakes in recent times.
Various lines of evidence have been considered to establish the likely cause of the reported water level decline. These have included consideration of Tahmoor Colliery operations, long-term rainfall records, broader catchment river flow data and regional groundwater levels.
No hydrology data exists for the lakes themselves, however the local and region hydrology data that is available indicates that the most likely cause of the reported water level declines in Thirlmere Lakes is due primarily to the prevailing climatic conditions. Specifically the continuing declining trend in rainfall, established during the recent severe drought, appears to be affecting on surface water runoff and recharge to groundwater. This trend needs to be reversed by extensive and protracted rainfall events before recovery in flows and lake levels can be observed.
As a result of this investigation, there was no evidence to suggest that mine fracturing or subsidence has affected the water levels in Thirlmere Lakes in any substantial way.
Read the full report: Thirlmere Lakes groundwater assessment (PDF 7.4 MB).
The NSW Office of Water has completed the drilling of four groundwater monitoring bores in the vicinity of three of the five Thirlmere Lakes at the Thirlmere Lakes National Park. Drilling was undertaken to address one of the data gaps identified by the NSW Office of Water in a groundwater assessment report published in December 2010. The lack of a groundwater monitoring record in the vicinity of the lakes has been a significant missing element in understanding the Thirlmere Lakes hydrogeologic environment.
The results of the completed drilling project have been documented in the Thirlmere Lakes drilling report (PDF 8 MB. Please note this will take 19 minutes to download at 56 Kbps). The report details the drilling and construction of the monitoring bores completed during May and June 2011. About 190 linear metres of drilling was successfully completed, of which samples have been collected for future research projects. A copy of the report was provided to the Thirlmere Lakes Independent Inquiry Committee.
The drilling will not result in immediate answers to the problem of declining water levels in the lakes, but the monitoring bores will be used to collect long-term information for future interpretation.
Additional works relating to the monitoring of lake levels and rainfall within the lakes catchment will be needed to complete the picture. The monitoring bores will provide evidence of groundwater level trends over the long-term as a progressive record of automatic data is gathered.
Groundwater review of Ashby Quarry
DPI Water has undertaken an review of the groundwater conditions at Ashby Quarry (PDF, 118.14 KB) near Maclean in northern NSW.