Can I drain my pool to the sewer in NSW?

Can I drain my pool to the sewer in Sydney?

Yes, and in Sydney it is the instruction rather than a permission. Sydney Water's connections and disconnections page, under ‘Drain a pool or spa’, says:

“Pool and spa water must not enter the stormwater system, as it's chlorinated and needs to be treated. Always discharge chlorinated water to the wastewater system.”

It gives two ways to empty a pool or spa: discharge the water to the wastewater system using the pool's pumping system and a backwash hose, or siphon the water from the pool and drain it to the wastewater system. The only size trigger it names is a 50 metre pool, the equivalent of an Olympic pool, which needs an application through Sydney Water Tap in to discharge trade wastewater.

In Sydney, pool water belongs in the sewer: Sydney Water says chlorinated pool and spa water must not enter stormwater.

Refilling is a separate question with its own history; see whether you need a permit to fill your pool and what it costs to empty and refill a pool. Pool builders covering the area are listed under Sydney.

Hunter Water's five conditions for pool backwash

Hunter Water, whose area of operations includes Newcastle and Lake Macquarie, publishes its position in a technical document rather than a household page: section 5.9, ‘Swimming Pool Backwash Discharge’, of its Standard – Wastewater Connections (Version 4, March 2024). Residential pool backwash may go to sewer, but only if:

1. it is connected by a designated sanitary drainage fixture trap and air gap;
2. the discharge pipe is at most 50mm;
3. it discharges at no more than 1 litre per second;
4. it is not carried out during rain;
5. the connection work is done by a licensed person.

The standard practice is to extend the backwash delivery pipe to an existing overflow relief gully, or a new one installed for the purpose, without blocking the gully grating (Standard Drawing TSS-007). Direct connection to the sewer or to the property's sanitary drainage is prohibited.

Hunter Water allows residential pool backwash to sewer only through an overflow gully with an air gap, from a pipe of at most 50mm, at no more than 1 litre per second, and not while it is raining.

The standard deals with backwash. It does not set a separate procedure for emptying a whole pool, so ask Hunter Water before draining the full volume. Because the connection is plumbing work, see whether pool pipework is plumbing work. Builders in the area are listed under Newcastle and Lake Macquarie.

Where the sewer is closed to pool water, even in NSW

The NSW answer has an exception. Hunter Water's standard states that residential swimming pool backwash discharge to sewer is prohibited in vacuum sewer system areas and in all pressure sewer system areas.

Hunter Water's vacuum sewer page puts the vacuum case slightly differently: swimming pool water and filter backwash “shall not discharge to a vacuum system without prior written approval”. We are showing both wordings because they are not identical. The practical reading is the same: on a vacuum or pressure sewer, do not send pool water to the sewer unless Hunter Water has told you in writing that you may.

How to tell which you have: the same standard lists Hunter Water's vacuum sewer areas as Dora Creek in Lake Macquarie and Sandgate in Newcastle, and describes a pressure sewer as a holding well with a grinder pump on the property that pumps wastewater to the sewer. If you have a sewage well and pump in the yard, assume the exception applies and ask.

Commercial, industrial and recreational properties are outside the residential rule altogether and must apply individually for pool backwash connections.

In Hunter Water's vacuum and pressure sewer areas, residential pool backwash to sewer is prohibited.

If you are building, the backwash route is worth settling in the quote rather than after handover: ask each builder where the backwash will discharge and whether a new overflow gully is included. You can compare pool quotes with that line in the brief, and how the pump and filter work explains what backwashing is.

NSW, WA and SA: three instructions for the same pool water

The table above completes a comparison that shows why national advice about pool water fails. Read at each utility's or regulator's own page:

• New South Wales: Sydney Water says always discharge chlorinated pool water to the wastewater system; Hunter Water allows backwash to sewer on conditions.
• Western Australia: Water Corporation states that backwash and drainage from domestic swimming pools and spas “are not considered as trade waste and are not permitted to be discharged to sewer”, and refers owners to their local government.
• South Australia: the SA EPA's information sheet says that in sewered areas backwash from all swimming pools can go to a sewerage drainage point, that new pools should be connected to the sewer with SA Water approval, and that South Australian legislation prohibits backwash to stormwater.

The same bucket of pool water is sent to the sewer in Sydney and kept out of it in Perth.

One rule held in every source we read that addresses it: not to stormwater. Sydney Water says pool water must not enter it; South Australia prohibits it. The WA position is in draining a pool to the sewer in WA.

Before you drain a pool in NSW

A short check, in order:

1. Who runs your sewer? The name on your water and sewer bill is the authority whose rule applies. Sydney Water and Hunter Water are the two covered here; if your bill comes from someone else, ask them.
2. What kind of sewer? In Hunter Water's area, a vacuum or pressure sewer closes the sewer to pool backwash.
3. Where will the hose go? Sydney Water names the wastewater system; Hunter Water names an overflow relief gully, via an air gap, never a direct connection.
4. Is it raining? Hunter Water says not during rain, and its standard separately says stormwater must not be discharged to its sewer.
5. Is it backwash, or the whole pool? Emptying a pool is a bigger job with a structural risk; read why a pool can lift out of the ground before you drain it completely.

Before draining a pool in NSW, check who runs your sewer, because Sydney Water and Hunter Water publish different conditions.

If you are weighing up renovating the pool you are draining, what a pool renovation costs sets out the published ranges.

Common questions

Sources

• Sydney Water — Connections and disconnections: Drain a pool or spa
• Hunter Water — Standard: Wastewater Connections, Version 4, March 2024, section 5.9
• Hunter Water — Vacuum sewer systems
• Water Corporation — Swimming pool discharge regulations
• SA EPA information sheet 181/04, Disposal of swimming pool backwash water, as published by Yorke Peninsula Council

General information only, current at 2026-09-28. Pool rules differ by state and by council, and penalty amounts are updated regularly. Confirm your own obligations with your council or a registered inspector before acting.