On a NSW rental property that runs its own septic tank or AWTS rather than town sewer, the landlord is responsible for keeping the system compliant and properly maintained, scheduled pump-outs, AWTS service contracts and any structural repair, while the tenant is responsible for how they use it day to day, not overloading it, not flushing things that damage it, and reporting problems promptly. Confusion usually comes from treating septic like any other appliance in a lease, when it’s closer to plumbing infrastructure the landlord owns and must keep compliant with council approval conditions, alongside a genuine expectation that tenants use it reasonably.
This guide sets out how that split typically works under the Residential Tenancies Act 2010 (NSW), where costs commonly land when something goes wrong, and where a dispute is actually settled if landlord and tenant disagree. It’s general information rather than legal advice; a specific lease, property condition report or NCAT matter should be assessed on its own facts.
Why septic maintenance sits differently to a normal rental repair
Most rental maintenance questions are simple: something breaks, the landlord fixes it, unless the tenant broke it through misuse or neglect, in which case the tenant can be asked to cover the cost. Septic and AWTS systems follow the same basic logic, but two things make them a bit more involved than a broken tap or a faulty light fitting.
First, an onsite sewage system in the Port Macquarie-Hastings LGA operates under a council approval to operate, issued to the property, with conditions around servicing frequency and standards. That approval sits with the property owner, not the tenant, so meeting it is squarely a landlord obligation regardless of what the lease says. Second, a septic system’s condition is genuinely affected by how it’s used, more people, more water, or the wrong things going down the drain, which means tenant behaviour has more influence over septic system health than it does over most other rental infrastructure.
What the landlord is responsible for
Under the Residential Tenancies Act 2010, a landlord must provide and maintain the premises in a reasonable state of repair, and for a septic or AWTS property that generally includes:
- Scheduled pump-outs. A conventional septic tank on its normal 3-5 year cycle is routine maintenance, the landlord’s cost, the same as servicing a hot water system.
- AWTS service contracts. Aerated systems need scheduled servicing, commonly quarterly in NSW, by an appropriately accredited provider, and keeping that contract active is a compliance obligation tied to the property’s approval, not something a tenant can be expected to arrange or fund.
- Structural repairs and system age. A collapsed baffle, a failed pump, or trenches that have simply reached the end of their working life are landlord costs, the same as any other ageing infrastructure a tenant didn’t cause.
- Council compliance. If PMHC issues a notice relating to the system, responding to it is the landlord’s obligation as the approval holder, even if a tenant is living there at the time.
What typically falls to the tenant
A tenancy agreement generally expects a tenant to use the premises, and anything connected to it, in a reasonable manner and not to intentionally or negligently cause damage. For a septic-connected rental, that ordinarily covers:
- Not flushing anything other than toilet paper and human waste. Wet wipes, sanitary items, nappies, cooking fat and chemicals down a septic-connected toilet or sink are a common, avoidable cause of blockages and system strain.
- Reasonable water use. A tenant isn’t expected to ration water, but sustained excessive use, for example running multiple long showers and a washing machine constantly for a household well beyond what the system was sized for, can genuinely shorten the time between pump-outs.
- Reporting problems promptly. Slow drains, odours, or a beeping AWTS alarm should be reported to the landlord or agent as soon as they’re noticed. A tenant who ignores an alarm or a backing-up toilet for weeks can be found to have contributed to a worse, more expensive outcome.
- Not interfering with the system. Lifting tank lids, tampering with an AWTS control panel, or attempting a DIY fix is a tenant risk, not a landlord expectation, and any damage caused this way is generally the tenant’s responsibility.
When a tenant’s actions cause damage or a blockage
If a septic or AWTS problem is traced to tenant misuse, wipes causing a blocked outlet, an AWTS alarm ignored until the blower burned out, or a system clearly overloaded by more occupants than the tenancy agreement disclosed, a landlord can seek to recover the reasonable cost of the repair from the tenant, generally starting with a bond claim and, if that’s disputed, an application to the NSW Civil and Administrative Tribunal (NCAT). The practical difficulty in these disputes is usually evidence: a written service history, photos from the pump-out or service technician, and a record of when the fault was first reported all matter far more than assumptions about “wear and tear” versus “damage.” A septic inspection carried out when a problem is first suspected, rather than after the tenancy has ended, produces exactly that kind of documented evidence for either side.
Holiday and short-term rentals are a different case
Where a rental is let short-term, an Airbnb-style holiday letting rather than a standard residential tenancy, the equation shifts further toward the owner’s responsibility, because the owner (or their managing agent) controls occupancy and turnover directly rather than a single tenant controlling day-to-day use. PMHC has flagged that an approved system’s capacity must reflect maximum likely occupancy, not just a nominal household size, which puts the onus squarely back on the property owner to size servicing around actual guest numbers and turnover, not to treat a holiday house’s septic system the same as a quiet permanent rental.
What does this typically cost, and who pays?
| Scenario | Typically the landlord’s cost | Typically the tenant’s cost |
|---|---|---|
| Routine pump-out on schedule | Yes | No |
| AWTS quarterly service contract | Yes | No |
| Blockage from wet wipes flushed by tenant | Sometimes (if repeated/clear misuse, may be tenant’s) | Often, if traced to specific misuse |
| System reaching end of life (age-related failure) | Yes | No |
| Ignored alarm leading to worse failure | Case by case, depends on evidence | Possibly, if delay is documented |
| Overloading beyond disclosed occupancy | Case by case | Possibly, particularly in short-term lets |
Our full septic pump-out cost guide sets out indicative pricing for the routine work landlords are generally responsible for arranging, and what pushes those numbers up.
Practical steps for landlords and property managers
- Keep a documented service history from day one, so any dispute over misuse versus normal wear has evidence behind it rather than opinion.
- Disclose the system type and its basic expectations to new tenants, a short note on what not to flush and how the system works reduces avoidable problems far more cheaply than any dispute afterwards.
- Act on tenant-reported issues quickly. A prompt pump-out or service call-out is nearly always cheaper than the emergency call-out that follows an ignored problem.
- Confirm council approval conditions are current, particularly at the start of a new tenancy or after a change of ownership, so the landlord’s compliance obligations are clear from the outset.
Frequently asked questions
Can a landlord charge a tenant for a routine septic pump-out?
Generally no. A routine pump-out on the normal multi-year cycle is ordinary maintenance and a landlord cost, in the same category as servicing a hot water system, not a tenant expense.
What if the tenant flushed something that blocked the system?
If a blockage or damage is clearly traced to specific tenant misuse, wipes, sanitary items or similar, a landlord can generally seek to recover the reasonable repair cost, usually via the bond and, if disputed, through NCAT. Documented evidence from the technician who did the work matters a great deal here.
Does the tenant have to arrange AWTS servicing themselves?
No. AWTS service contracts are tied to the property’s council approval, held by the owner, so arranging and paying for scheduled servicing is a landlord responsibility, not something delegated to a tenant.
What should a tenant do if the AWTS alarm goes off?
Report it to the landlord or managing agent immediately. A prompt report protects the tenant from any later suggestion they contributed to a worse outcome by ignoring it, and gets the system serviced before a minor fault becomes an expensive one.
Who is responsible if the system fails simply because it’s old?
Age-related failure, a tank or trenches reaching the end of their working life, is a landlord cost. Tenant responsibility generally only comes into play where misuse or clearly unreasonable use can be shown.
Get a septic system properly assessed before a dispute starts
Whether you’re a landlord wanting a clean service record before a new tenancy begins, or trying to work out whether a current problem is wear-and-tear or tenant misuse, a documented septic inspection is the practical way to get an independent, written answer. Get a free quote and tell us the property’s situation; the right assessment can be lined up from there.