Workers down at the site are busy laying 450-millimetre-diameter pipeline alongside the existing 600-millimetre pipeline which connects to the St John Street sewer rising main.

READ MORE: Two children dead, more hurt in jumping castle accident

The new piping will allow the rising main to divert overflow sewage to the Ti Tree Bend Sewage Treatment Plant.

Previously, during heavy rainfall, the overflow sewage was discarded into the river as the existing pipes were unable to manage the excess volume.

By diverting the sewage, the project is expected to improve the river's water quality.

The upgrade is part of the Launceston City Deal, which has brought together state, federal and council funding to improve the city in a few key areas - including the quality of its waterways under the Tamar Estuary River Health Action Plan.

READ MORE: Man tests positive to COVID after arriving in Tasmania

The pipe laying at the St John Street sewer rising main is estimated to cost $1.5 million and the works are scheduled to be completed in early 2022.

Once up and running, the improvements to the water quality are expected to follow in the coming months and years.

Our journalists work hard to provide local, up-to-date news to the community. This is how you can continue to access our trusted content: