In most cases, you must obtain a licence to construct a dam or other works on a waterway and in some cases you will need a licence to construct an off-waterway dam.
You should contact us on 1800 013 357 if you are considering constructing or undertaking works on a dam to discuss your proposal and the potential licensing requirements.
Do I need a licence to build a new dam or construct works?
If you propose to construct a dam (or other structure such as a weir) on a waterway which will be used to take, use, convey or store water you are required by law to apply for a licence to construct works.
A waterway includes a river, creek, watercourse, lake, lagoon, swamp or marsh – but also includes natural channels or dams with a catchment of 60 hectares or greater. The requirement for the catchment area to be 60 hectares does not apply if the feature is supplied from spring activity.
Generally you will be required to make application to GMW for a waterway identification prior to submitting your application for a Works Licence.
Depending on the proposed size of the dam, you may also need a licence to construct and operate a dam which is not located on a waterway if it is considered large or potentially hazardous due to its size or capacity being:
- 5 metres high with a capacity of 50 megalitres or more; or
- 10 metres high with a capacity of 20 megalitres or more; or
- 15 metres high, regardless of the capacity.
You do not need a licence to construct a dam that is to be used only for domestic and stock purposes as long as the dam is not located on a waterway and is below the above height and capacity thresholds.
What should I consider before I decide to construct a new dam?
You should contact GMW if you are considering constructing a dam or undertaking works to discuss your proposal and the potential licensing requirements.
If the dam is to be used for irrigation or commercial purposes, you will be required to apply for a Licence to Take and Use Water whether the dam is on a waterway or not and regardless of its size. The extraction of water from all river basins in Victoria is capped. This means that new entitlements cannot be issued and you will need to transfer entitlement from an existing licence entitlement holder.
In some areas, you may be able to purchase existing entitlements from another licensee who does not wish to utilise their full entitlement volume. Prior to deciding whether or not to construct a dam you should fully investigate the likelihood of obtaining a water entitlement in your area.
The Licence to Take and Use Water and water entitlement must be obtained prior to the construction of a new dam as you may be required to incorporate particular works relating to the take and use of water into the dam’s construction. It is highly recommended that you also contact your local Council to ascertain if you require a planning permit for your proposed dam. All applications that relate to the construction of a new dam, or the alteration of an existing dam will be referred by GMW to the relevant Catchment Management Authority, the local Council, and the Department of Energy, Environment and Climate Action – so potential applicants are encouraged to discuss their proposals with them prior to lodging application with GMW to better understand their requirements.
Applicants will need to engage a suitably qualified engineer to design, supervise and sign off on the dams construction if the dam is located on a waterway, or if the dam meets or exceeds the potentially hazardous dimensions above. The engineer will also be required to prepare a Dam Safety Surveillance Plan and Dam Safety Emergency Plan.
Applicants may also be required to advertise at their cost their intension to apply for a licence to construct a dam, as well as notify neighbours. GMW need to take into account any submissions received as a result of these processes.
Who is responsible for the safety and maintenance of private dams?
Private dam owners are legally responsible for the safety of their dams and any damage the dam may cause if it fails. If you intend to construct a new dam on your property, you will be required to undertake regular inspection and maintenance to keep the dam in good order.
Do I need a Works Licence to carry out maintenance or clean out my existing dam?
You should contact GMW prior to commencing work to ensure the works you are proposing do not require a licence.
You can carry out routine maintenance works on a dam without requiring a licence providing the works are limited to:
- Clearing out weeds
- Cleaning out silt to the original bed level of the dam – but not increasing the capacity beyond that of the original dam
- Removing vegetation from the dam wall
- Minor works to repair erosion damage on the crest, embankment or spillway up to 1,000mm in the dam wall (apart from vertical in the spillway crest) providing the back fill is compacted appropriately.
- Maintenance of the compensation pipe or trickle pipe
- Any works that put at risk the integrity of the dam, weir or other structure will require a works licence and are not considered routine maintenance. This type of work includes:
- Any alteration to the capacity or wall height
- Modification of the crest, spillway, compensation pipe or trickle pipe
- Reconstruction of the dam wall due to damage
- Repairs that result in a disturbance to the embankment – such as removing a section of the embankment to replace or repair a compensation pipe or trickle pipe.
When can I commence construction?
If your application to construct a private dam/ other works is approved, you can commence construction of the licensed works. The construction licence is valid for 12 months from the date of issue, after which it will expire. The proposed dam or other works must be completed before the expiry date.
The licence will include a list of conditions that you and your chosen contractor or engineer must read and be aware of before you commence the works. The licence conditions will vary depending on the proposed use, location, size and type of dam you intend to build.
When construction is complete do I need to obtain an Operating Licence for the dam?
By law, many dams require an Operating Licence. This include dams that are:
- Situated on waterway regardless of size
- 5 metres high with a capacity of 50 megalitres or more; or
- 10 metres high with a capacity of 20 megalitres or more; or
- 15 metres high, regardless of the capacity.
An operating licence requires that dam owners prepare a Dam Safety Surveillance Plan which will usually also require the periodic inspection of the dam by a qualified engineer. In addition, dam owners must hold a Dam Safety Emergency Management Plan to be implemented in the event of a dam failure or other structural deficiency.
Where can I get more Information?
You should contact us on 1800 013 357 to discuss your proposal with one of our Licensing staff or Diversions team members. You can find our Licence to Construct Works at our Forms page.
An excellent source of information for prospective dam owners is the Victorian Government's Your Dam: Your Responsibility document, which can be downloaded from the Dam Safety Guidance webpage.
GMW reference: A3709205