Construction Underway on Major Water and Waste Pipelines


​​24 May 2019

Construction is underway to build two major pipelines from Clyde to Alexandra — one that will bring an improved water supply to Alexandra and Clyde, and the other that will transport Clyde's wastewater to the Alexandra Wastewater Treatment Plant.

Contractor Fulton Hogan started work on the project this week in the Alexandra area.

"This is an exciting time getting the construction phase of these significant district projects underway. Once completed, they will bring major environmental and well-being benefits to the Clyde and Alexandra communities and to Central Otago," says CODC Capital Projects Programme Manager Patrick Keenan.

Initial work has begun on the outskirts of Alexandra where the pipeline will connect with the town's northern reservoir and follow a route adjacent to the Otago Central Rail Trail to Clyde.

In this first phase a water pipeline will be laid from the site of the main line up to Alexandra's northern reservoir. On the main line, work will begin to lay two pipes – one for water and one for waste - in a trench that runs parallel to the Otago Central Rail Trail between land adjacent to the Alexandra netball courts and Clyde. The pipes will be laid one metre apart in a trench.

"Our goal is to minimise disruption to the community as much as possible and our contractors will do their best in this regard, however it is inevitable there will be some in places. While crews are working on this part of the pipeline construction there may be limited access to the berm between Dunstan Road and the Otago Central Rail Trail. Car parking in front of the Alexandra netball courts could also be affected while crews are working in the adjacent area," says Mr Keenan.

A key part of early work on the project is welding lengths of 450mm PE pipe together to create 120m lengths (see photo below). Each weld is a process of aligning, blading, heating and hydraulic force to connect pipes together. The licensed welders who undertake this work mark each weld with a unique serial number as quality assurance.

The project to lay the two pipelines is expected to be completed around the middle of next year. The pipelines will predominantly run along the Central Otago Rail Trail corridor and for short lengths along the edge of State Highway 8.

Cost and disruption to the community is reduced by constructing both the wastewater and water supply pipelines at the same time.

One pipeline will take water from bores at Lake Dunstan and transport it to the Alexandra reservoir before it is distributed from Alexandra's northern reservoir via existing pipelines to the Alexandra community. It will also deliver water to the Clyde community, linking up with existing water pipelines.

The other pipeline will transport waste from Clyde's new reticulated wastewater system to the Alexandra Wastewater Treatment Plant. The reticulated system will replace the town's septic tanks and disposal fields, significantly improving the quality of Clyde's urban discharges.

The $13.6 million Stage 1 of the Clyde Wastewater Project includes both installing the pipeline, a pump station and the new reticulated wastewater system in central Clyde, with work planned to begin in autumn 2020. Over the coming year, the Council will provide more information to the Clyde community on how Stage 1 will be implemented.

The cost of the water supply pipeline and bore work for the Lake Dunstan Water Supply project is $9 million.

Regular project updates

In the next few weeks the Council will begin publishing a monthly update In the Pipeline to keep the community informed about the project. People who are interested in the project's progress will be able to sign up to In the Pipeline on the CODC website at:​​

In the Pipeline will also be available in print at key locations in Alexandra and Clyde.​

Page reviewed: 24 May 2019 4:17pm