Dam safety scheme
Part 2, subpart 7 of the Building Act 2004 and the Building (Dam Safety) Regulations 2008 set the framework for the Dam Safety Scheme. The dam safety scheme applies to existing large dams and new large dams once they have been commissioned.
The dam safety provisions of the Building Act 2004 come in to force on 1 July 2010.
Potential Impact Categories
Owners of large dams are required to prepare a Potential Impact Category (PIC) for their dam. A PIC classifies the potential impact of a failure of a dam on persons, property and the environment according to criteria set in the Building (Dam Safety) Regulations 2008. A detailed description of how to calculate a dam’s PIC can be found in the document Dam Safety Scheme - Guidance for regional authorities and owners of large dams: Navigating the Dam Safety Scheme
PIC must be submitted to Greater Wellington by 1 October 2012 for dams commissioned prior to 1 July 2012. For dams commissioned after 1 July 2010, owners have three months from the date that the dam was commissioned, to provide classification information to Greater Wellington.
Each PIC submitted to Greater Wellington must be accompanied by a certificate from a recognised engineer that:
- states the PIC accords with the prescribed criteria and standards for dam safety; and
- states the engineer is a recognised engineer; and
- has attached to it evidence the engineer is a recognised engineer.
Recognised Engineers
A recognised engineer is an engineer who:
- has no financial interest in the dam concerned; and
- is registered under the Chartered professional Engineers of New Zealand Act 2002; and
- has the prescribed qualifications and competencies.
The Institution of Professional Engineers New Zealand (IPENZ) is the professional body which represents professional engineers from all disciplines in New Zealand.
Greater Wellington recommends that dam owners look through the IPENZ website listing of recognized engineers to check that the engineer they have chosen to make the classification of their dam has a current CPEng.
High impact dams must be assessed by a Category A Recognized Engineer listed on IPENZ website.
Low impact dams can be classified by either a Category B or Category A Recognized Engineer.
We suggest that the dam owner asks their selected engineer to answer the minimum of these two questions in writing:
- does the engineer have ability and experience in general civil engineering?
- is the engineer a CPEng and competent to perform the work involved?
This is because a dam owner may not be highly skilled or knowledgeable in the dam safety scheme and may need some advice.