The Natural Resources Access Regulator (NRAR) sent officers to Dubbo this week as part of its statewide check on bores flagged as possibly drawing more groundwater than permitted.
They also travelled to Narromine and Hillston as part of Operation Drawdown.
The officers were investigating "11 potential instances of excess water extraction" on the Macquarie Groundwater Source and Hillston, and the Lower Lachlan Groundwater Source.
A NRAR spokeswoman said the Macquarie Groundwater Source included the Upper Macquarie Alluvial Aquifer, extending from Wellington to east of Narromine.
The on-site investigations followed a desktop audit of 226 approvals for bores across the two groundwater sources.
Licence holders were sent letters advising them of the NRAR's intention to "visit for further assessment".
The NRAR reports that the use of modern technologies and intelligence streams like drones, satellite imagery and water accounting, allows it to detect non-compliance "quickly and efficiently".
Operation Drawdown began earlier this year with the inspection of bores on properties on the Lower Murrumbidgee Groundwater Source in the Griffith district.
The NRAR's manager compliance monitoring and audit (West-Murray Darling) Dr Tara Schalk said the major goal of the audit was to determine rates of compliance with bore extraction limits on the groundwater sources.
"Extraction limits are applied to bore licences to ensure fair sharing of what is a limited water resource," she said.
"This protects the water source, the rights of other water sources and any dependent ecosystems."
Earlier this year the NRAR penalised Tamworth Regional Council for taking water it was not entitled to from the Scott Road drift wells.
The Northern Daily Leader reported on September 9 of the events leading up to an investigation by the NRAR.
It told of two $1500 fines being imposed on the council after the NRAR concluded total extraction was 375.67 megalitres (ML), an over-extraction of 310.59ML.
The NRAR has been established to be an "independent, transparent and effective regulator with total carriage of the compliance and enforcement of water management legislation in NSW".
Before the establishment of the NRAR, regulation of water in NSW was the responsibility of the Department of Industry and WaterNSW.
To make a confidential report on suspected water misuse, call the NRAR hotline on 1800 633 362 or email email@example.com.
For more information about the NRAR, visit industry.nsw.gov.au/nrar.