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Guidelines for referable dams

Failure impact assessment

Guidelines for failure impact assessment of water dams (PDF, 389.5KB) have been developed to help owners comply with dam safety conditions and legislation. The assessment identifies:

  • dams with a Category 1 failure impact rating: these put between two and 100 people at risk, or
  • dams with a Category 2 failure impact rating: which put more than 100 people at risk.

A dam with a Category 1 or Category 2 failure impact rating is classed as 'referable' under the provisions of the Water Supply (Safety and Reliability) Act 2008 and the Water Act 2000.

If a dam is assessed as not having a population at risk, it is not subject to the referable dam provisions.

Category 1 dams, and non-referable dams that exceed the size criteria (requiring them to be failure impact assessed) must be re-assessed at intervals of no less than five years.

A dam meets the size criteria if it’s either: 

  • more than 10 metres high and has a capacity of more than 1500 megalitres
  • more than 10 metres high, has a capacity of more than 750 megalitres and a catchment area more than three times its maximum surface area at full supply level.

A failure impact assessment will also need to be carried out if the owner of a non-referable dam either:

  • proposes to carry out works that will mean the dam meets the above size criteria
  • has a dam which meets the above criteria, and increases the storage capacity of the dam by more than 10 per cent.

Important documents for dam owner/operators

New referable dams

Under the Sustainable Planning Act 2009 a development permit is required for all new dams that require a failure impact assessment due to the proposed size and all modifications to existing referable dams which increase storage capacity by more than 10 per cent.

Development permit applications must be made using the forms required by the Integrated Development Assessment System (IDAS) process of the Sustainable Planning Act 2009.

If you have problems downloading any of these documents please contact:

Queensland Water Supply Regulator
PO Box 15456
City East Q 4002
Email: ewswsssqwsr.corro@dews.qld.gov.au

Related information

Last updated
28 January 2014