Dam safety regulations now in force

The regulations have been made to increase the resilience and safety of Aotearoa/New Zealand’s dams, protecting people, property and the environment from the potential impacts of dam failures.

Only classifiable dams are impacted by the regulations. Dams are classifiable if they are 4 or more metres in height and store 20,000 or more cubic metres volume of water, or other fluid.

Immediate steps for dam owners:

1. If you are the owner of a water retention structure, you need to determine if your structure meets the definition of a dam.

   The definition of a dam in the Building Act 2004(external link) — New Zealand Legislation
   
   If yes, go to step 2.
   If no, no further action is required under these regulations.

2. Determine if you have a classifiable dam (that is, if it meets the height and volume threshold stated above).

   How to measure and calculate your dam [PDF 7.9MB](external link) — Building Performance
   
   If you have a classifiable dam, go to step 3.
   If you do not have a classifiable dam, no further action is required under these regulations.

3. Determine your dam’s potential impact classification (PIC).

   Determine a dam’s PIC(external link) — Building Performance(external link)
   
   Go to step 4.

4. Have the PIC audited and certified by a Recognised Engineer. 

   Find a Recognised Engineer(external link) — Building Performance(external link)
   
   Go to step 5.

5. Submit your dam’s classification certificate to the relevant regional authority by 13 August 2024.

   Dam classification certificate template [PDF 68.5 KB](external link) — Building Performance

In addition to these steps, owners of dams with a medium or high PIC have further actions they need to take.

The only additional requirement for owners of dams with a low PIC is to review their dam’s PIC within 5 years of the regional authority approving it.

Background to the regulations

The regulations were made by the Government in May 2022 and provide a nationally consistent approach to dam safety. Having a dam safety framework brings Aotearoa/New Zealand in line with most other countries in the Organisation for Economic Co-operation and Development (OECD).

The 2-year timeframe between the regulations being made and their commencement, was to allow time for dam owners, technical practitioners, Recognised Engineers and regional authorities to understand and prepare for the regulations.

Since May 2022, the Ministry of Business, Innovation and Employment (MBIE) has been working with industry groups and regional authorities to ensure dam owners are aware of the regulations and provide them with information and resources to support them.

Further information and resources

Read more about the regulations, and find resources to support you, on MBIE’s Building Performance website.
Dam Safety(external link) — Building Performance(external link)

This includes:

• a resource to help dam owners calculate the height and volume of their dam to see if they are impacted by the regulations
• information on the actions dam owners need to take if they are impacted, and
• a recording of the webinar MBIE hosted in April 2024, which includes a question and answer session.

Dam safety requirements(external link) — Building Performance

Implementation timeframes(external link) — Building Performance  

Resources(external link) — Building Performance

Building (Dam Safety) Regulations 2022(external link) — New Zealand Legislation