Our River. Our Future

Revitalising kanamaluka/Tamar estuary

The kanamaluka/Tamar estuary is a special landscape that connects our community. We appreciate its importance to Launceston and the wider community, which is why we are making investments today to ensure its health for future generations.

As part of the Tamar Estuary River Health Action Plan (TERHAP), we are delivering new sewerage infrastructure for the city to improve the health of kanamaluka/Tamar estuary and the environment that surrounds it.

What's this project all about?

The Ti-Tree Bend Sewage Treatment Plant Covered Storage Project will involve the construction of a new network storage tank that has two compartments, an overflow tank, and a balance tank, with a combined capacity of 10 megalitres.

The future flows to these new storage tanks will be transferred via the New Sewer Pipeline we are currently building 40 metres under the estuary riverbed between our Margaret Street Pump Station and the Ti-Tree Bend Sewage Treatment Plant.

Once completed, this new storage capacity will enable us to temporarily store and buffer any incoming flows from the combined Launceston sewer system before we then transfer these flows to the existing plant for the final phase of treatment.

Project update

Over the past few months we have been continuing with site ground improvement works in preparation for the construction of a new 10 megalitre covered storage tank.

The ground improvement works, including the excavation of well over 12,000 tonnes of materials, is to make sure that we have a strong and solid base to build the new tank on.

To support this important ground preparation work for the new tank we are utilising a technique called Mass Soil Mixing (MSM).

MSM involves mixing the existing soil with grout, to form something resembling wet concrete. Once hardened it will provide a solid, firm surface for construction, as well as help to prevent ground water infiltration.

We have a large excavator equipped with a hydraulic rotating mixing head that is attached to a 7-metre arm. The grout material is being pumped out through the mixing head while it rotates to liquify the soil to create the hardened base panels, which are 3 metres squared and up to 7 metres deep.

We have completed roughly 85% of the MSM.

As well as carrying out the MSM works, we will also be undertaking Continuous Flight Auger Pilling. This form of piling is a relatively quiet technique in comparison to noisy pile driving and will give us a firm foundation to build the tank upon.

Towards the end of the year, we expect to complete the foundation works and then begin constructing the new 10 megalitre covered storage facility and supporting infrastructure.

The new storage tank is designed to take the flow from the New Sewer Pipeline, meaning less overflow events into the kanamaluka/Tamar Estuary.

The project is expected to be completed during 2026.

Construction Images

The Tamar Estuary River Health Action Plan (TERHAP or the Plan) is an initiative of the Tamar Estuary Management Taskforce (TEMT) and the Launceston City Deal, to improve the health of kanamaluka/Tamar Estuary.

TERHAP is jointly funded by the Australian and Tasmanian governments, the City of Launceston and TasWater.

Tamar Estuary River Health Action Plan Projects