One of Coe’s most recently completed projects (August 2006), was on behalf of the Priority Sewerage Program Team Alliance Team (PSPAT) in Sydney.
The alliance, consisting of Sydney Water Corporation, John Holland, MWH Australia, United KG and Manidis Roberts was commissioned to improve the sewerage services in Mulgoa, Wallacia and Silverdale. The project is part of Sydney Water’s Priority Sewerage Program.
By connecting to the now-completed scheme residents will be helping to protect this environmentally sensitive area, as well as helping to reduce public health risks by reducing the runoff of partially treated wastewater into the Hawkesbury Nepean River.
Coe Drilling’s scope of works was to install two directional boreholes. The first bore was 890 m of DN 250 HDPE 100 PN 12.5 pipe as part of the Warragamba Transfer Main. This section was completed by HDD utilising the CoeDrill l80 spread.
The borehole was drilled in Hawksbury sandstone using a 6¾ inch Wenzel Mud Motor and was ultimately opened up to a final diameter of 16 inches to accommodate the HDPE pipe.
The second bore hole was for the Treated Effluent Discharge Main. This part of the works was subcontracted to Perry Infrastructure who used a 450 vacuum microtunnelling system to drill the 230 m bore to accommodate the DN 400 HDPE product pipe.
Current projects
Coe Drilling is currently nearing the completion of another HDD project for Sydney Water consisting of two rising main 300 m bores as part of the Holsworthy Sewerage Scheme Transfer. These works are part of the South Western Sydney Sewerage Scheme, which will meet the needs of population growth in southwest Sydney.
The pipe installed for the first rising main, completed in August 2006, was DN 710 HDPE 100 PN16 and the pipe for the second rising main is DN800 HDPE 100 PN16. Completion of the second bore was scheduled for September.
Drilling for the first main was through shale using a 6¾ inch Wenzel Mud Motor and the pilot holes were opened up to a final diameter of 36 inches for the first bore and 38 inches for the second bore to accommodate the HDPE pipe. Both bores were completed using the CoeDrill 680 spread.
Future projects
Coe Drilling’s experience in the lucrative drilling conditions of the Sydney basin has been once again acknowledged with the recent award of another major HDD contract.
On this occasion Agility Management has engaged Coe Drilling to install four river crossing using HDD for the 20 inch Sydney Primary Gas Loop Project. Mobilisation for the project is currently underway.
Other company news
Coe Drilling has recently appointed Dimce Sijakovski in the role of Business Development Manager. Dimce is a qualified Civil Engineer with 15 years of postgraduate experience, of which the last seven have been in the Trenchless Technology industry.
