The Victorian Government has released the findings of an independent review into water quality issues in the Anglesea River.


The review, conducted by Professor William Maher, found low pH and elevated metal levels resulted from natural sources in the catchment.


The findings follow an investigation by then Environment Protection Authority (EPA) that linked fish deaths to low pH levels and elevated metals in the river system.


The Victorian Government responded by commissioning Professor Maher to conduct a review into:


  • the history of acid events in the Anglesea estuary;
  • sources of acidic water and metals to the estuary;
  • the role of specific factors such as land-use in the catchment, licensed discharge into the river and water extraction; and
  • options for remediation


Professor Maher concluded:


  • Low pH waters resulted from natural processes in the catchment in which sulphides in coal and other pyritic materials are oxidized
  • There is no evidence of any significant input of acid from oxidation of sulphur dioxide emitted from Alcoa's coal-fired power plant.
  • A flush of acid occurs after prolonged periods of low rainfall, followed by soaking rain.
  • Large amounts of aluminium, iron, boron and probably associated trace metals are generated and transported naturally during acid formation.


As a result of the review, a 24-hour monitoring station will be installed to measure real-time water quality data and to support the estuary's management.


Corangamite Catchment Management Authority will review the current Anglesea River Estuary Management Plan with other key agencies and input from the local community.

The EPA will develop an Anglesea River Response Plan with assistance from Surf Coast Shire and other relevant agencies. This plan will outline roles and responsibilities of all agencies in the effective management of the Anglesea estuary in the event of future incidents in the river.


The release of the findings came two days before the Victorian Government announced it had approved the 50 year extension of Alcoa's coal mining lease at Anglesea. The extended lease will require Alcoa to submit a map of planned mine activities, potential environmental impacts and how they will be managed.  Future expansion of the mine will be limited to three per cent of its 7145 hectares lease area, and be subject to a new environmental process.

New environmental controls over processes at the coal mine will be established through legislation to be introduced to Parliament next week.