Located on the Macquarie River, the picturesque city of almost 40,000 people is also home to the Taronga Western Plains Zoo and the Old Dubbo Gaol. Some of its more unique attractions include Terramungamine Reserve, which features about 150 grooves created by Aborigines who once used the hard stone to sharpen their stone axes. With more than 8.3 kilometres of off-road cycle paths and close proximity to surrounding towns, Dubbo is also a city for cycling enthusiasts. Effective maintenance of the city’s underground infrastructure ensures the comfort of Dubbo’s permanent residents and many annual tourists.
Having recently been named a finalist in the Local Government and Shires Association Excellence in Environment Awards for its water-saving initiatives, Dubbo has every right to be proud of its advanced infrastructure development and maintenance. Trenchless techniques play an important role in achieving water-saving initiatives such as reducing infiltration and exfiltration.
Importance of trenchless
Thanks to the continually developing nature of construction and rehabilitation techniques, Mr Reynolds enjoys working with a variety of rehabilitation and maintenance projects. Other key people responsible for the delivery of essential services are Director Technical Services Stewart McLeod, Manager Water Supply and Sewerage Geoff Bellingham and Asset Planning Engineer Steve Carter.
During his ten years as Infrastructure Engineer Water and Sewerage with Dubbo City Council, Mr Reynolds has at times faced challenges. One of the greatest challenges that the Council faces is finding the right contractor to undertake the work. “In order to provide the best contractor for each project, suppliers are sourced through open administration on an individual project basis [and subject to thorough examination before being awarded the tender]”, said Mr Reynolds.
Finding the right contractor is of the utmost importance so that other peripheral challenges such as “sprawling urban development, remote villages and water security will be handled effectively”.
Dubbo City Council is responsible for the maintenance of a significant amount of Dubbo’s underground infrastructure, including 309 kilometres of gravity sewer, 468 kilometres of water reticulation and 164 kilometres of stormwater drains.
Dubbo City Council inspects approximately 20 per cent of its assets and needs to repair or replace less than that each year. CCTV technology plays an important part in the inspection process, as all sewers that encounter a choke are subject to inspection via CCTV. In addition to the ongoing inspection work, approximately $A600,000 is spent annually on sewer rehabilitation and approximately $A500,000 on the replacement of water mains, the majority of which is undertaken using Trenchless Technology. The Council uses Pipepak and Maintenance Reporting systems Water/Sewer/Plant to keep track of the asset management program.
The decision of which method of technology is utilised depends on a number of factors, including the geographic location, the effect on residents, and the depth and cost of the project. The main trenchless techniques used by the Dubbo City Council include relining, pipe bursting, HDD, thrust boring and CCTV.
On the cards for Dubbo City Council
Dubbo has implemented a long-running schedule, which will account for the next 20 years of inspection and repair. Mr Reynolds said there is also an upcoming project that may require microtunnelling – stay tuned for more information.
