What's this project all about?
TasWater has made a commitment to reduce our environmental risk at sites across the state.
The outfall will be relocated from the Kermandie River to deeper water of the Huon River, where there is better dilution and dispersion and ultimately, better environmental outcomes.
The treated
effluent outfall from the Geeveston Sewage Treatment Plant is currently
situated in the Kermandie River. Due to poor dilution and dispersion in the
Kermandie River the outfall needs to be relocated to deeper water with better
dilution and dispersion and ultimately, better environmental outcomes.
The outfall will be moved to a location in the Huon River, 260 metres offshore, south of Shipwrights Point, at a depth of 13 metres. This location has been selected due to the optimal dilution and dispersion.
As part of the project an 80kL storage tank will be installed at the upgraded pump station. This emergency storage will help to reduce the frequency and volume of overflow events.
Stormwater entering our sewerage network is the main contributor to sewerage overflows. We are currently delivering a project to 'Keep stormwater out of sewer'. Flow monitoring has been completed in Geeveston and a number of areas have been identified as having stormwater inflow and infiltration issues. Investigations will continue over the coming months on both our own infrastructure which may need repair, and private properties which may be incorrectly plumbed to the sewerage network. We will then work to rectify these issues.
The relocation of the outfall is step change to improve environmental outcomes for the region, with Master Planning currently underway for additional long-term improvements.
Following recent community consultation, we will now work to finalise design for the project, with construction due to commence in late 2024.
Alternate Investigations updates
Concerns on the proposed outfall relocation site have been raised and we are currently undertaking further investigations to determine if we can achieve the best environmental outcome at an alternate site.
Investigations continue into alternate outfall locations. Two locations in the Huon River off Whale Point have indicated that a good environmental outcome can possibly be achieved.
We are now working through land-based investigations and should construction be deemed feasible on land approximately 12 months of further environmental assessments will be required.
We are in the final stages of options analysis. A multi criteria options assessment and risk assessment has been undertaken for five options. Options include both Shipwrights Point and Whale Point.
Early in the new year we will re-engage with the local community to discuss the outcomes of the option assessments.
Following 12 months of investigations which were focussed on alternate options to construct the outfall off Whale Point. We assessed an option to lay a submarine pipeline from the Kermandie River or options to trench a pipe through land. We have undertaken marine studies, assessments of threatened species and Aboriginal heritage, analysis of engineering options and a multi criteria options assessment that considers the environment, community and constructability.
Our investigations have recommended that to achieve the best outcome for the environment the outfall should be constructed off Shipwrights Point, however the recommended outfall location has changed from the original and is now in deeper waters and further offshore, south of the recreational area.
The recommendation presented to the community in January 2024 was approved by the TasWater Board in April 2024.
This discussion is being communicated with the community throughout the month of May.
