Dam Development

Do you need to build, deepen or enlarge a dam, or remove an existing one? These works are considered to be a Water Affecting Activity (WAA) and require a permit.

The development of a new dam can impact existing water users and the environment and must be managed in a way that balances existing and future needs.

Regulating the development of dams means that we can manage and prevent:

• reduced flows to downstream users
• reduced flows or changes to the timing of flows to ecosystems that depend on a certain flow regime
• erosion and sedimentation, and
• increased salinity.

This approach is needed to ensure water is shared equitably between all users and the environment.

Permit Requirements

Before constructing, modifying or removing a dam, you will need to get approval under either the Landscape South Australia Act 2019 via the Murraylands and Riverland Landscape Board or under the Planning, Development and Infrastructure Act 2016 via your local council.

The criteria for determining which act your dam works falls under are:

• If the dam is smaller than 5 megalitres (ML) and has a wall height less than 3 metres, you will need to apply for a permit for a water affecting activity (WAA) through the landscape board.
• If the dam is bigger than 5ML, or has a wall height greater than 3 metres you must apply for development approval from your local council (development applications will be referred to the Murraylands and Riverland Landscape Board by the council for direction).

How long does it take to get a water affecting activity permit?

The exact time taken to process the application depends on the nature of the activity, the time of year and the information provided in the proposal. You will need to apply for your permit at least two months in advance of scheduled construction works. Permits are usually valid for one year from the date of issue.

Definitions of dams to help you with your Water Affecting Activity permit

What is an off-stream dam?

An off-stream dam refers to a dam, wall or other structure that is not constructed across a watercourse or drainage path and is designed to hold water diverted, or pumped, from a watercourse, a drainage path, an aquifer or from another source. Off-stream dams may also capture a limited volume of surface water from the catchment above the dam.

An off-stream dam that will not capture any surface water (often referred to as a turkey nest dam) and will not sit in a drainage path may not require a WAA permit. It is recommended that you contact the Water Planning and Assessment Officer to discuss your proposal in the first instance.

What is an on-stream dam?

An on-stream dam is a dam, wall or other structure placed, or constructed on, in or across a watercourse or drainage path for the purpose of holding and storing the natural flow of that watercourse or the surface water.

What is a low flow bypass?

A low flow bypass is a structure, such as a small weir, used to direct low stream flows around dams and back to their normal course of flow. Low flow bypasses ensure some water is retained in the stream so that downstream environments, which may include fish, frogs and riparian vegetation may receive water to survive. A low flow bypass is one of many conditions that may be enforceable on your permit to construct an on-stream dam.

Criteria for issuing permits

The Murraylands and Riverland Water Affecting Activities Control Policy and water allocation plans for prescribed surface water areas set out the criteria by which any application for a dam will be assessed. Policies and principals may vary between landscape board regions and water allocation plans. We recommend you review the Murraylands and Riverland Water Affecting Activities Control Policy and appropriate water allocation plan to be clear about the principals that apply to your circumstances.

These principles cover criteria including (but are not limited to):

• local soil conditions and salinity
• impacts on downstream users
• remnant vegetation
• protection of aquatic ecosystems
• dam construction and design
• the number and size of dams
• the need for low flow bypasses
• protection of habitat for threatened species
• special criteria relating to on-stream dams

A Murraylands and Riverland Landscape Board officer may undertake a site inspection to determine if the site of the proposed dam is ecologically sensitive or prone to erosion and salinity.

Taking water from dams in prescribed areas

WAA permits do not allow for the taking of water in prescribed areas. This is dealt with separately by the issuing of a water licence. A water licence may be needed to use your dam water for activities such as irrigation, industrial use, commercial use, stock and domestic use and managed aquifer recharge.

For information in relation to water licensing please contact the regional water licensing branch of the Department for Environment and Water on 8595 2053 before constructing a dam or taking water.

Penalties may apply

Please ensure you are not in breach of the Landscape South Australia Act 2019.

Undertaking a water affecting activity without a permit or, in breach of the permit conditions is an offence under the Act. If you are unsure whether the works you are proposing will require a permit, call the Water Planning and Assessment Officer for advice before undertaking any works.

The serving of protection orders or criminal/civil enforcement notices may be undertaken by the Murraylands and Riverland Landscape Board or the Department for Environment and Water for breaches of the act. Financial penalties or prosecution may also apply.