Dams, safety & consents

The Taranaki Regional Council transferred its Building Act responsibilities to Waikato Regional Council in 2008 for efficiency reasons.

Initial enquiries about dams can be made to the Director — Resource Managment, Taranaki Regional Council. The Taranaki Regional Council still deals with resource consents for dams under the Resource Management Act. There are few existing or expected large dams in the region required to be consented under the Building Act.

Building a dam

This page provides initial information to all those who own a dam or canal, or are planning to construct, modify or remove a dam, canal or a structure associated with a dam. All dams must comply with the NZ Building Code, and all large dams (over 4m in height and retaining more than 20,000 cubic metres of water or other fluid) require a building consent. Medium to large dams are also likely to require a resource consent under the Resource Management Act.

A dam's safety is dependent on its design, construction and how it's managed, operated and maintained so there are a number of requirements to take into account.

Large farm dairy effluent storage and treatment facilities that are more than 4m high and hold more than 20,000 cubic metres of waste water will also need a consent under the Building Act. Contact this Council for further details.

Applications forms, brochures and checklists

Downloadable documents from the Waikato Regional Council website can be accessed via links on this page. These are subject to change from time to time, so if you print a hard copy please check that it’s up to date.

Farm dams

Small dams do not require a resource consent. Bigger dams do.

• Small farm dams, not designed for river or flood control or to drain land or wetlands, are generally allowed without a resource consent if certain conditions are met.
• An exception is the Stony River catchment, where any damming is prohibited.
• The conditions are to protect the waterway ecology and the stability of the streambed.
• If the dam is more than four metres high and stores more than 20,000m³ you need a building consent from the Regional Council (see above).

What you need to ensure

• The catchment area upstream of the dam is less than 25 hectares.
• The dam is no more than three metres high.
• You are not damming water outside of your own property or causing a buildup of water on neighbouring properties.
• The dam can let floods pass, via a proper spillway, and does not alter the natural course of the river.
• You are not restricting anyone else's water supply or resource consent.
• No significant environmental effects, including scouring, erosion, or restriction of fish passage is occurring.
• No contaminants from equipment are being allowed to enter the river (make sure you do not refuel any equipment in the riverbed).
• The dam does not restrict fish passage.
• Construction does not take place between 1 May and 31 October in areas covered by water, due to fish spawning during this time.
• The Council is informed that you are going to dam the stream, at least two working days before you start work.

If you cannot meet all of these requirements, you may still be able to construct the dam but you will need a resource consent.

Dams register

The Taranaki Regional Council and other Regional Councils are required under the Building Act to maintain a register of all dams no matter their size for their respective regions.

The register enables Councils to contact dam owners on matters of importance to them, such as new regulations and guidance material on dam safety. If you own a dam, then you should check with the Council whether your dam should be on the register.