Short answer: In most cases, small farm dams that capture rainfall runoff fall under harvestable rights in NSW and don’t require a water access licence. However, council planning rules are separate — whether you need a development application depends on your Local Environment Plan. The safest first step is to check with both your local council and WaterNSW before you break ground.
If you’re a new dam owner (or you’ve just bought a rural block), the approval side can feel like a maze. One person says “no worries, everyone builds dams“, another says “you’ll get fined. The truth is: both can be right — because NSW rules change based on location and the type of dam.
This guide is written for beginners. No legal jargon, no assumptions. Just a practical checklist you can follow before you spend money on an excavator.
Two different “approval systems” can apply
In NSW, there are usually two buckets to think about:
- Planning approval (council) — this is about land use and development rules in your local area.
- Water approvals/licences (state water rules) — this is about whether you’re allowed to build a structure that captures or stores water from a water source.
You might need one, both, or neither — depending on your situation.
The simplest question to start with: is it a harvestable rights dam?
In plain English, a harvestable rights dam is usually a small farm dam that captures rainfall runoff from your own property (not water pumped from a river), within NSW’s harvestable rights rules.
NSW water rules generally allow landholders to capture and store a portion of rainfall runoff under harvestable rights without needing a water access licence or water supply work approval, as long as you meet the harvestable rights requirements.
Important: “No water approval needed” does not automatically mean “no council approval needed”. Council planning rules are separate.
Council approval: it depends on your Local Environment Plan (LEP)
NSW guidance is very clear that the need for planning consent for a dam can vary between council areas depending on the local planning rules in the Local Environment Plan (LEP).
In some areas, a dam may be allowed without development consent if it qualifies as exempt development — and the “exempt” criteria can vary (it might consider wall height or thickness, not just volume).
What to do: ring your local council (or check their website) and ask: “Is a farm dam on my property exempt development, or does it need a DA?
Beginner checklist: what you need to know before anyone can answer you
When you talk to council or WaterNSW, they’ll usually ask the same core questions. Here they are in a simple table.
| Question | Why it matters | What you can do today |
|---|---|---|
| Where is the dam (property address + GPS pin)? | Different councils and different water rules apply in different areas. | Drop a pin in Google Maps and write down the coordinates. |
| Is it capturing rainfall runoff, or pumping from a creek/river? | Harvestable rights is typically about rainfall runoff; taking from a water source can trigger licences. | Write down where the water will come from in normal rain and dry periods. |
| Is the dam on a gully or on a bigger watercourse? | Some exemptions depend on stream type. | Mark the flow path on a map and take photos after rain. |
| What size are you planning (approx. capacity and wall height)? | Planning exempt development rules can depend on wall height; water rules can depend on allowable capacity. | Ask your dam builder for a rough concept size and wall height. |
| What is the dam for (stock, house, irrigation, firefighting)? | Purpose can change which rules and exemptions apply. | Make a short list of your intended uses. |
Water approvals in NSW: when you might need them
NSW’s water approvals framework is separate from council planning. If your dam is not exempt, you may need approvals such as a water supply work and/or water use approval, and in some cases a water access licence.
If you’re not sure whether your dam is exempt (for example, whether it qualifies under harvestable rights rules), it’s worth confirming before you build.
Other approvals that can apply even for harvestable rights dams
Even where harvestable rights rules apply, NSW guidance warns you may still need approvals under other legislation depending on your site and impacts — including planning rules, fisheries impacts, crown land, biodiversity, and coastal management.
A quick call to council and WaterNSW is cheaper than hoping for the best.
Key takeaways
- In NSW, dam approvals can involve both council planning rules and state water rules.
- Whether you need council approval often depends on your LEP and whether the dam counts as exempt development in your area.
- Many small rainfall-runoff dams may fit harvestable rights rules, but you still need to meet the requirements.
- If your dam isn’t exempt under water rules, you may need water approvals or licences before construction.
- Other laws can still apply (biodiversity, fisheries, coastal), so checking early avoids expensive rework.
FAQ
Do I always need a DA to build a dam in NSW?
No. Whether you need development consent can differ by council area and the rules in your Local Environment Plan (LEP). Some dams may qualify as exempt development depending on the criteria your council applies.
If my dam is harvestable rights, does that mean I don’t need any approvals?
Not necessarily. Harvestable rights can mean you don’t need certain water approvals, but council planning rules may still apply. You may also need approvals under other legislation depending on location and impacts.
Who do I call first: council or WaterNSW?
Call both. Council can advise on DA/exempt development under your LEP, and WaterNSW can help you confirm if the dam is exempt under water rules.
What if I build first and ask later?
That can get expensive quickly. If the dam needs approval and you didn’t get it, you may be required to modify it, reduce its size, or even remove it. It’s worth confirming first.
For technical guidelines on farm dam design and water management in Australia, the NSW Department of Primary Industries and Agriculture Victoria publish authoritative reference materials.
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