New pipeline supports health of the Kanamaluka/ Tamar estuary

Vinidex supplied a large-bore HDPE pipeline solution for a major TasWater project – including tailored resin selection, large wall thicknesses, and carefully coordinated logistics across road and sea – supporting a seamless installation and long-term environmental outcomes for the Kanamaluka/Tamar estuary.

About the project

As part of the ongoing Tamar River Health Action Plan (TERHAP), a major milestone was reached in 2024 with the completion of a new 3km underground sewer pipeline in Launceston. The project scope included:

• DN1000 open trench installed pipe, 1130m
• Two DN900 Horizontal Directional Drilling (HDD) sections, 650m and 1,100m

The construction works involved installing the large pipes through a combination of land-based trenching and drilling beneath the estuary riverbed, with some sections reaching depths of up to 45 metres. The pipeline was one of the largest infrastructure projects of its kind in the Southern Hemisphere.

The pipeline will improve TasWater’s capacity to transfer sewage and stormwater, helping to reduce the frequency and volume of overflow events significantly. In turn, it is anticipated to support improved health outcomes for the Kanamaluka/Tamar estuary and the surrounding environment.

Delivering long term benefits to Launceston

The TERHAP project is designed to improve the operation of Launceston’s combined system, which manages both sewage and stormwater. With an estimated flow capacity of around 900 litres per second, the upgraded infrastructure will divert sewage and stormwater flows away from the Kanamaluka/Tamar estuary, reducing the frequency and volume of overflow events.

The completion of the TERHAP projects will see a 70 per cent reduction of nutrients discharged to Kanamaluka/Tamar estuary, providing improved environmental outcomes for the estuary and surrounding areas.

Key project challenges

• Two HDD river crossings – 650m and 1,100m in length – were installed 45m beneath the riverbed through challenging geotechnical conditions.
• The pipe was manufactured in Toowoomba, QLD, and delivered to Launceston via road and sea – requiring detailed logistics planning to manage the journey down the east coast and across Bass Strait.
• The large bore pipeline required on-site large-scale welding equipment, careful planning, and efficient utilisation of trench space.
• Installation took place in a residential area with high public exposure.

The Vinidex solution

Vinidex provided support to the final pipeline design to minimise cost and optimise flow. Even after the contract was signed, Vinidex continued working closely with TasWater’s Capital Delivery Office project team to accommodate changes to fitting requirements.

“Supplying this project gave us the opportunity to showcase the strength of our products and the depth of our technical capability. From resin and fitting selection to logistics, we worked hand in hand with the project delivery team to ensure a seamless installation that will support Launceston’s wastewater management and health of the Kanamaluka/Tamar estuary for decades to come.”

Joe Barresi, Technical Sales Engineer, Vinidex

The large pipe sizes and pressure requirements for the pipeline necessitated large wall thicknesses. To ensure uniformity, a unique low-slump resin was specially sourced for the project to achieve a consistent wall thickness around the pipe’s circumference.

Vinidex produced one of the largest wall thickness pipes ever made by an Australian manufacturer. The DN900 SDR9 pipe featured a minimum wall thickness of 100mm, while the DN1000 SDR11 had a minimum wall thickness of 90.2mm. The consistent wall thickness achieved with the low-slump resin supported efficient welding and provided for a seamless installation.

The 3km of large-bore pipe was manufactured at Vinidex’s world-class extrusion facility in Toowoomba, QLD. Transporting the pipe down Australia’s east coast and across the Bass Strait required careful logistics planning – including safe loading and restraint of the pipe, and coordination of two transportation companies using a single trailer to minimise handling.

Vinidex also provided specific pre-slinging of the pipes, as requested by the welding contractor, to assist with unloading on-site. Deliveries were tightly scheduled to meet project milestones, in close coordination with TasWater.

Further information

You can find more details about PE Pressure Pipe on the product page.