Most lifestyle blocks in Nelson–Tasman rely on on-site wastewater systems. Looking after yours protects your property, your waterways, and your wallet.
How often should you pump out?
As a general guide, most septic tanks need pumping out every 3 to 5 years. The exact interval depends on tank size, household size, and what goes down the drains. If you have a secondary treatment system, it may need more frequent servicing — check the manufacturer schedule.
Warning signs to watch for
- Slow drains or gurgling sounds from pipes
- Damp patches or unusually green growth near the tank or disposal field
- Sewage odours inside or outside
- An alarm sounding from your treatment system
- Overflow or ponding at the disposal field
If you notice any of these, call a septic contractor promptly. Delaying can lead to more expensive damage and potential health risks.
What not to put down the system
- Wet wipes, sanitary products, or nappies (even those labelled flushable)
- Cooking fats, oils, or grease
- Harsh chemicals, bleach, or paint
- Food scraps in quantity
These can clog the system, kill the beneficial bacteria, or damage the disposal field.
When to call a professional
You should call a septic contractor if:
- It is time for your scheduled pump-out
- You notice any of the warning signs above
- You are buying a property and want the system checked
- You are installing a new system or altering an existing one (council consent is required)
Questions to ask a septic contractor
- How often should my specific system be pumped out?
- Can you locate and access my tank if I am not sure where it is?
- Do you service the brand of treatment system I have?
- What records do you provide for council compliance?
- What warning signs should I watch for between services?