Environment Canterbury is responsible for issuing building consents for large dams, as well as ensuring large dams are well constructed, regularly monitored and that the potential risks to people and property are minimised.

A building consent is required for all structures that meet the definition of a large dam, including flood control dams, significantly modified natural features and canals, as well as structures that form part of large dams, such as appurtenant structures.

A large dam is defined in the Building Act 2004 as a dam that has a height of four or more metres and holds 20,000 or more cubic metres of water.

Environment Canterbury is a Building Consent Authority (BCA) accredited with International Accreditation New Zealand and also registered with the Ministry of Business, Innovation and Employment(external link).

You can find a brochure about the consenting process for large dams here and answers to some common questions below.

Common questions

Use the drop-down menus below for answers to some common questions and email our Building Consent Authority co-ordinator for further information — or ring customer services on 0800 324 636.

How do I apply for a building consent to build a dam?

A building consent allows you to carry out building projects in accordance with the consent and associated plans and specifications.  Applications for building consent must be submitted on the prescribed form (Form F002), in accordance with the Building Act 2004 and Building Regulations, which is also available for download at the bottom of this page.

You will need to provide all information requested in the form, including two sets of drawings, two specifications and a Certificate of Title.

Once you have submitted your application, it will be vetted for completeness to ensure that enough information has been supplied.  If there is information missing you may be asked to resubmit the application when the missing information is available.

When all required information is provided the application will be formally received for processing. You will be advised of this in writing.

An application may be put on hold until sufficient information has been received.

You can make your application via post or by delivering it personally to Environment Canterbury’s customer services counter at 200 Tuam Street, Christchurch or 75 Church Street, Timaru.

Do I need a Project Information Memorandum (PIM) to construct a dam?

Although not mandatory, we strongly recommend you obtain a Project Information Memorandum (PIM) from Environment Canterbury, as well as the relevant district or city council, before submitting a building consent application.

Information contained in these PIMs may be critical in the processing of your building consent, such as:

  • details of any stormwater systems which relate to your proposal
  • potential natural hazards
  • any land classifications imposed on your property by organisations such as the Department of Conservation or the Historic Places Trust
  • any resource consents that already apply to the property.

If applications are made without a PIM, it is likely that further information will be required. This can result in an increased processing cost and timeframe.

You can apply for PIMs at any time and should consider this information during your building design.

Do I need resource consent to construct a dam?

Resource consents may be required under the Resource Management Act 1991 when taking, using, damming and diverting water is anticipated.

Works associated with dam construction may also trigger the requirement for a resource consent, for example carrying out earthworks.

Obtaining a building consent does not preclude anyone from needing resource consent.

Resource consents must be approved before dam construction commences.

How is a building consent for a large dam processed?

Environment Canterbury must decide whether or not to grant your application within 20 working days from receipt of all required information.

We will initially vet your application for completeness to ensure that sufficient information has been provided.  This part of the process can take up to five working days. If accepted, the regulatory time clock starts.

We will contract expert consultants to assess your application to make sure that the completed dam, when constructed, will comply with building code. 

If we refuse your application, you will be advised in writing and reasons will be given for the decision.

If your application is granted, we will advise you by letter. The letter will include a set of conditions that must be complied with. The consent itself will be issued only upon payment of fees incurred during processing.

The time frames for the building consent process are:

  • 20 working days to grant or refuse a building consent
  • 20 working days to grant or refuse a Code Compliance Certificate
  • 12 months to start work from the date the consent was issued
  • 24 months limitation period, to complete work.
Can I start building work on my dam before I have all of the necessary consents?

Generally no building work may start without building, subdivision or resource consent; however, there are some situations where building work may proceed after obtaining permission from the council. This must be discussed with our BCA co-ordinator, who will need to see details of your plans prior to any decision-making.

What are the ongoing responsibilities of the landowner/applicant after a building consent is issued?

Once a landowner has secured the necessary building consents and resource consents to construct a dam and has been issued with the Code Compliance Certificate, the Building Act 2004 requires them to:

  • confirm classification of their dams against regulatory standards as having low, medium or high potential impact (potential impact categories are outlined in the Building Act 2004), which refers to the impact of a failure of the dam on persons, property or the environment
  • register the dam and its classification with the appropriate regional council
  • provide an annual dam compliance certificate, if the dam is classified as having medium or high potential impact.

The landowner/applicant must submit this information to a recognised engineer for audit, who will then provide a Code Compliance Certificate to Environment Canterbury for approval.

The Code Compliance Certificate provides a record of completed building work and is intended as written evidence that the work is legal. It will be approved if Environment Canterbury is reasonably satisfied that the building work complies with the New Zealand Building Code and engineering standards.

Landowners/applicants of dams with a classification of medium or high must prepare and submit a dam safety assurance programme and provide an annual dam compliance certificate. A recognised engineer must undertake this work on the applicant’s behalf.

The classification must be reviewed within five years after the regional council approves it and at intervals of no more than five years after that.

The owner must also review the dam’s classification if, at any time, building work that requires a building consent is carried out on the dam and the building work results in, or could result in, a change to the potential impact of a failure of the dam on persons, property or the environment.

Existing dam owners must also review the information they supply to the regional council to determine whether it will meet the requirements of the Building Act 2004.

Landowners/applicants must meet the costs of engaging recognised engineers to audit and prepare documentation. You must ensure the engineer you engage is competent and has the necessary experience and qualifications relating to dam engineering and safety assurance. Links to helpful contacts are provided at the bottom of this page.

How do I make a change to the building consent for a large dam?

In any building project it may not be possible to comply with the approved consent documentation. In these circumstances, amendment may be required.

We will consider whether any variations materially affect the approved building consent documentation and, in consultation with a consultant, decide if the proposed changes can be processed as a minor variation or if an amendment to building consent application is required.

You can find an amendment to a building consent form using the document search button at the bottom of this page. You must also supply two copies of supporting documentation.

Why has my building consent been suspended?

It is not unusual for additional or amended information to be needed to confirm compliance with the Building Act 2004.

In such cases, we will request further information by telephone, fax, mail or email and the consent will be suspended.

The suspension effectively stops the 20 day process period. It will be lifted once a satisfactory answer has been received.

How much does it cost to get a building consent for a large dam?

The cost of processing a building consent is generally time-based, so the quality of the information provided with your application will affect the overall fees (i.e. poor quality drawings and details will take longer to process and will cost more).

Environment Canterbury also requires to receive building levy and BRANZ levy with the building consent fee and forward levies to the government. 

Payments are to be paid before consent is issued and before CCC is issued.

Costs are set out in the Schedule of Fees in our Annual Plan.

How much time do I have before I must start building?

You must start building work within 12 months of the date of issue of your consent otherwise it will lapse automatically — unless Environment Canterbury has already agreed in writing to an extension of time.

An extension of time must be obtained from Environment Canterbury prior to the 12 month lapse date. It cannot be approved retrospectively. Beyond the lapse date, you will need to apply for a new consent.

How long after starting my building project do I have to complete the work?

Building work must be completed within two years of the granting of the building consent — unless an extension is agreed by Environment Canterbury.

If all building work is not likely to be completed within the two years, you must send a written request to extend the consent before the two-year period is up.

How is a project inspected and certified?

When a building consent is granted, you shall be advised of any conditions and expectations. There will be a number of site inspections during construction and a final inspection will be required on project completion. This will be arranged by our BCA co-ordinator.

The dam owner is required to apply to Environment Canterbury for a Code Compliance Certificate as soon as practicable after all building work is completed. The certificate will be issued if we are satisfied that building work has been completed in accordance with the granted building consent.

The Code Compliance Certificate also confirms that the project has been legally constructed in accordance with the Building Code.

What is a Notice to Fix?

A Notice to Fix is a statutory notice requiring a person to remedy a breach of the Building Act 2004 or the Building Regulations. It can arise from identification of illegal building work or from work not undertaken in accordance with an issued building consent.

What is a Certificate for Public Use?

Environment Canterbury may, as a regional authority, allow public use of a dam before it has been issued a Code Compliance Certificate (section 363A of the Building Code 2004).

Those who own, occupy or control a dam may apply to Environment Canterbury for a Certificate for Public Use for the dam, or part of the dam, if it has building consent, and if Environment Canterbury is satisfied on reasonable grounds that members of the public can use it safely.

What are producer statements used for?

Producer statements have no specific status under the Building Act 2004; however, they can be used as a mechanism for helping establish compliance with the Act and the Building Code.

Environment Canterbury and external consultants acting for Environment Canterbury must have confidence that people providing producer statements have appropriate experience and competence in their field and must assess the content and accuracy of each producer statement that is supplied.

What is a Certificate of Acceptance?

A Certificate of Acceptance may be issued by Environment Canterbury for work that required a building consent, but was carried out without consent. It allows for certification of work that has, for example, been carried out urgently because of safety issues.

How do I make a complaint about my building consent?

As a building consent authority, we take all complaints seriously. All complaints are recorded and actioned promptly. To make a complaint please phone Customer Services on 03 353 9007 or 0800 324 636 or email ecinfo@ecan.govt.nz

We require the following information:

  • Date incident occurred
  • Nature of complaint (vetting, lodgement, inspection, notice to fix, code compliance certificate or compliance schedule)
  • Copies of any supporting information (if applicable)
  • Name and contact details – to enable us to respond to you

Your complaint will be responded to within 5 working days of receipt of your complaint, where you may be asked for further information to allow us to investigate your complaint through a fair review process. We will keep you informed of progress during any investigations if required.

Our aim is to resolve complaints within 20 working days. There may be situations where your complaint needs to be directed elsewhere, in which case we will let you know and point you in the right direction. 

If you are unhappy with the outcome of your complaint, you have a right to appeal and request a review of the decision. All appeals must be made in writing setting out the reasons why you disagree with the decision.

The BCA's complaint policy and procedures ensure appropriate levels of objectivity and fairness to all parties, enables complaints to be prioritised and provides remedies proportional to the issue raised. 

If you disagree with the technical decisions made in the consent, inspection/certifying process, there is a determination process available through MBIE.

Useful websites


Environment Canterbury and contractors engaged to undertake regulatory review work are not able to provide design or technical advice. Dam owners and building consent applicants should seek their own technical advice. This may include obtaining a peer review of the proposed design of the dam. The applicant has the responsibility to make sure enough detail is provided in the plan of the proposed building work, the specifications and other documentation.