Dam safety in the spotlight

8 Jul 19

The Ministry of Business, Innovation and Employment has opened consultation on proposed safety regulations for New Zealand’s large dams. The regulations would bring into effect the framework for dam safety, which could see a raft of new monitoring and compliance requirements for dams across New Zealand. Dam safety regulations were developed in 2008 but were revoked before coming into force in 2015. If you own a large dam or are a regional authority, these regulations propose potentially onerous obligations that you have the opportunity to have a say on.

Concern regarding dam safety in New Zealand has mounted due to the proliferation of agricultural dams, the age of many of New Zealand’s dams, the scale of hazards that dams are exposed to (such as earthquakes, floods and storms), and as new infrastructure is being developed downstream. In addition, a number of large dam failures overseas have brought the consequences of dam failure into the spotlight (for example the Brumadinho dam disaster in Brazil earlier this year and fatal dam failures in Kenya, Afghanistan, Laos and Myanmar in 2018).

The proposed regulations include a national safety framework for “classifiable dams”, those being:

  • at or above 4 metres in height and 20,000 cubic metres in volume; or
  • less than 4 metres in height, but at or above 30,000 cubic metres in volume.

Of the approximately 3,284 dams across New Zealand, at least 903 will meet this threshold, while 1,562 are too small and the balance of 819 will probably have to be assessed for classification. The threshold is likely to be met by dams used for a range of activities, including hydro, mining, water supply and farming.

The owners of classifiable dams will be required to engage a Recognised Engineer to assess the potential impact classification (PIC) of the dam. The PIC is based on the estimated consequences on downstream populations, property, and the environment, if a dam were to fail. If the PIC of a dam is assessed as “low”, the dam owners will have limited regular ongoing obligations. As set out in the Building Act, if the PIC is assessed as “medium” or “high”, dam owners must:

  • develop a dam safety assurance programme (DSAP) (to be audited and certified by a Recognised Engineer) to monitor the safety of their dam, and undertake periodic reviews of their DSAP;
  • take actions identified as necessary in the DSAP to maintain the safety of their dam, such as regular monitoring, or the inspection and maintenance of appurtenant structures; and
  • report compliance with the DSAP to their regional authority through an annual dam compliance certificate (which must include confirmation from a Recognised Engineer that, except for identified, minor items of non-compliance, all procedures in the DSAP have been complied with)

The onus will be on dam owners to provide the correct information to regional authorities. However regional authorities will be required to:

  • establish and maintain a register of dams;
  • approve, or refuse, DSAPs for medium and high PIC dams;
  • develop dam safety policies for dangerous dams, earthquake-prone dams and flood-prone dams; and
  • enforce compliance with the proposed regulations and the Building Act.


Want to know more?

More information on the proposed regulations is available here. If you have an interest in submitting Anderson Lloyd can provide specific advice on how the proposed regulations may affect your assets and whether changes are required to the regulations to make them more workable.

Submissions are due 6 August 2019


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