The Environment Protection Authority (EPA) has concluded its assessment of a proposal by TasWater for the proposed replacement and expansion of Selfs Point Wastewater Treatment Plant in New Town.
The proposal is for a new larger wastewater treatment plant (WWTP) to accommodate predicted flows from both the existing Selfs Point WWTP and those currently treated by Macquarie Point WWTP. The treatment capacity of Selfs Point WWTP will be increased from 10.4 ML/day to 24.9 ML/day to provide adequate treatment capacity for anticipated catchment growth over the next 30 years.
Discharge from the upgraded Selfs Point WWTP will be predominantly through the existing outfall located at Blinking Billy Point. During infrequent high-intensity wet weather events and other abnormal operating scenarios, discharge will be allowed to occur from a new outfall at Selfs Point.
The Chair of the EPA Board, Andrew Paul, said that the Board concluded that the proposed development can be managed in an environmentally sustainable and acceptable manner, with certain conditions. The Board requires these conditions to be included in any permit subsequently granted by Hobart City Council.
“Various environmental issues were considered in the assessment, particularly water quality impacts on the Derwent Estuary from the changed treated effluent discharge regime, potential for nuisance odour impacts and construction noise," Andrew Paul said.
“The proposal is for a new wastewater treatment plant using membrane bioreactor technology and will result in significant improvements to the quality of effluent discharged to the Derwent Estuary compared to the current arrangements. Discharge will be predominantly to the existing outfall located off Blinking Billy Point at 32 m depth where it will be quickly diluted and dispersed.
The proposed design includes measures to collect and treat air emissions from the most odorous components of the wastewater treatment plant through an odour control system and dispersed through a 14 m stack. Modelling in the Environmental Impact Statement indicates that under normal conditions odour should not be detectable. Permit conditions require odour emissions to be controlled, for the model conclusions to be validated and if necessary, for further odour treatment to be installed to prevent environmental nuisance.
Early construction works, due to the site conditions, will require 24 hour drilling and piling works to occur over several months with potential noise disturbance for nearby residents. Permit conditions restrict construction activities outside of daytime hours and require a construction noise management plan to determine appropriate mitigation measures to reduce the impact of drilling and piling works.
Public consultation was open for 28 days from 9 May 2024. No representations were received in relation to the proposal.
The proposal was considered by the Board in the context of the sustainable development objectives of the Resource Management and Planning System of Tasmania (RMPS), and in the context of the objectives of the Environmental Management and Pollution Control System (EMPCS) established by the Environmental Management and Pollution Control Act 1994 (EMPCA).
The functions of the Board are to administer and enforce the provisions of EMPCA, to further the RMPS and EMPCS objectives and, in particular, to use its best endeavours to protect the environment of Tasmania.
The Board undertook assessment of the proposal in accordance with the Environmental Impact Assessment Principles defined in Section 74 of the Act.
The environmental assessment report, including the environmental conditions, has been issued to TasWater and Hobart City Council.
The decision in relation to TasWater's proposed expansion of Selfs Point Wastewater Treatment Plant can be viewed on this website.
Published on:
31/07/2024