Dams

Water assist

Not sure where to start with your water licence or approval enquiry?

Water Assist is an easy step-by-step tool to help you find the information and support you need for water licensing and approvals.

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About dams

People construct and use dams for several reasons, including:

large scale water supply
supply farm stock and irrigation water
environmental management and erosion control.

Dam regulation and management

The construction and use of dams is regulated under the Water Management Act 2000 and managed by the department, WaterNSW and Dam Safety NSW.

The role of the department includes issuing licences and approvals for

government agencies – local, state, and Australian
water utilities, water supply authorities and licensed network operators under the Water Industry Competition Act 2006
mining activities
irrigation corporations
public schools and hospitals
Aboriginal communities and businesses
State significant development and infrastructure

The role of WaterNSW includes:

issuing licences and approvals for all other people constructing farms dams. See: WaterNSW water supply works and water use approvals
managing the complex network of dams, storages and pipelines to supply water to its customers across Greater Sydney and Regional NSW. See: WaterNSW dams in NSW

The role of Dam Safety NSW includes:

ensuring the safety of all declared dams in NSW - structures that Dams Safety NSW consider to be dams in accordance with the Dams Safety Act 2015 and the Dams Safety Regulation 2019. More information at: Dams Safety NSW

Find more information about what each agency does at: Water agencies

Exemptions

Not all dams need a licence or approval under the Water Management Act 2000. You do not need a water supply work approval in these circumstances:

Dams for specific purposes located on a ‘minor stream’, and constructed and used for one of the following purposes:
- control or prevention of soil erosion
- flood detention and mitigation
- capture, containment and recirculation of drainage and/or effluent to prevent the contamination of a water source
- specific environmental management purposes that are approved in writing.
Stock and domestic dams
- constructed under section 7 of the Water Act 1912 before 1 January 2001
- constructed before 1 January 1999, on a minor stream, in Western Division
Harvestable rights dams
Exemptions also apply for dams approved for State significant development and State significant infrastructure. Further details are provided below.

Before undertaking any works, check if an exemption applies to your dam at: Water licence and approval exemptions

If your dam isn’t exempt, you’ll need:

a water supply work and/or water use approval
a zero share access licence.

Types of dams requiring a licences and approvals

Dams that are not exempt need a water supply work and/or water use approval and a water access licence.

Information on how to apply for this licence and approval are available below:

Dams constructed as part of a State significant development and infrastructure project

When a dam is identified and the impacts are assessed as a part of a state significant development or infrastructure (SSD/SSI) project a water supply work and/or use approval is not required.

However, a water access licence with sufficient entitlement to account for the water take is still required unless an exemption under the Water Management (General) Regulation 2018 applies.

Find more information about water requirements for state significant development and infrastructure at: Major projects

Harvestable rights dams

Harvestable rights dams allow landholders (owners or occupiers of land) to capture and store a proportion of the rainfall runoff from their landholding in one or more harvestable rights dams without a water supply work and/or water use approval and a water access licence. Harvestable rights dams can be used for any purpose.

See: Harvestable rights for detailed information on:

harvestable rights rules
areas
maximum harvestable right dam capacity (MHRDC)
calculator for maximum harvestable right dam capacity
harvestable rights orders

WaterNSW provides support to landholders relating to harvestable rights dams. Find more information on constructing harvestable rights dams, water licences and approvals at: WaterNSW Basic landholder rights

Related guides and resources

Use these resources to help you determine if you need a water supply work and use approval to construct and use a dam, and a water access licence: