Emptying Septic Tanks and Waste Water Systems.

Our vehicles are clean and well maintained and our operators are helpful and professional.

Discover why we've earned the loyalty of thousands of customers. We offer septic tank services to suit everyone. 

Call our Freecall Number on 0800 725 326 (Option 2), or send us an email to sonia@nmwaste.co.nz 

We are always running specials on Domestic Septic Tanks , please take a look at our Facebook Page for specials we are currently offering in your area.

Waste flows into your septic tank where it settles and is partially broken down by bacteria. Your tank may have one or more chambers. The diagram below shows a two chamber tank.

Fats and solids remain in the tank. Liquid, which has separated from heavier particles, flows into the disposal field whenever new raw effluent enters the tank. In the disposal field, the separated liquid continues to be treated by natural processes.

The type of disposal field depends on soil type, the slope of the section, vegetation and underlying rock.

Your septic tank is a living ecosystem where bacteria do the work of digesting and treating waste.

The contents of a healthy septic tank form 3 layers:

  • Heavy, solid particles settle at the bottom of the tank forming a layer of sludge.
  • Light materials, including fat and grease, float to the surface forming a layer of scum.
  • Raw effluent containing large amounts of dissolved pollutants including salts and nutrients, nitrogen and phosphorus are sandwiched between the sludge and the scum. Raw effluent contains disease causing pathogens such as viruses, bacteria and worms.

Bacteria break down some organic solids, which helps reduce the build-up of sludge.

Scum helps prevent odors escaping and stops air entering the tank.

Active Waste Water Treatment Systems

In active new style wastewater treatment systems, the separated liquid flows into an additional aerated or other treatment chamber before entering the drainage field. Systems are more effective at turning the separated liquid into usable waste water because of the aerobic bacterial activity in this extra step. Consequently you should be able to use waste water from wastewater treatment systems in irrigation drip lines, if desired.

Signs of a Problem

You may have a problem with your septic system when:

  • There is a bad odor coming from your septic system;
  • Toilets and plugs drain very slowly;
  • Waste water is pooling on the drainage field;


These problems can be caused by any one or more of the following factors:

  • A sludge build up in the tank caused by infrequent emptying;
  • Non-biodegradable chemicals being put down the drains, killing the useful bacteria required to make your septic tank system work efficiently;
  • Other unsuitable items such as fats and grease are being disposed of into the system, this can clog the gravel in the disposal field;
  • There is damage to the pipes, either by tree roots or by fractures in the pipes;
  • The disposal field is water-logged (either through heavy rainfall or too much water going to the system at once e.g. shower/bath water and washing water).

Septic Tank Maintenance

To maintain and protect your septic tank system, we recommend the following:

  • Clean (empty) your septic tank regularly, at least once every three years;
  • If you have a waste-disposal unit for food scraps, your septic tank should be cleaned out annually, as sludge will build up rapidly;
  • Use only toilet cleaners and other detergents suitable for septic tank systems (i.e. avoid using and disposing of bleaches, whiteners, nappy soakers, stain removers & disinfectants (in large amounts);
  • Do not use disinfectants to clean the toilet bowl, as disinfectants will kill the useful bacteria in the tank;
  • Do not dispose of anything, other than effluent and toilet paper in the toilet (i.e., avoid disposing of baby wipes, cigarette buts, sanitary pads, tampons, disposable nappies, condoms in the toilet);
  • Do not dispose of anything, other than water and system friendly detergents down drains (i.e. avoid disposal of grease, chemicals, pesticides and oils, paints, varnishes & paint thinners, cold water soap powders);
  • Protect the drainage field by avoiding driving vehicles or grazing stock on it and divert storm-water away from the area;
  • Do not allow deep rooting trees or shrubs to grow over drainage pipes or the disposal area.

Septic Tanks Terms & Conditions of Trade

At Nelson Marlborough Waste we provide professional, reliable and tidy services to all our domestic customers. Servicing all areas at the Top of the South and available to you 24 hours a day 7 days a week every day of the year. Please see below our Terms & Conditions with regards to your Septic Tank.


We are committed to giving our customers a professional and reliable service at a highly competitive price.

Our standard prices for Septic Tanks includes the following:

  • Our operator and truck on-site for 1 hour;
  • Disposal fees for up to 3,000 Litres (an average tank holds 2,500 Litres);
  • All prices are inclusive of GST.

Additional Labour Charges:

Most septic tanks take between 30 and 45 minutes to empty.  In the event that our operator is working at your property for longer than 1 hour then $70.00/Hour will be added to your account (Only for the extra time).

Factors, which can affect the time it takes to empty your Septic Tank include:

  •  Where the Septic Tank lid is difficult to expose because its deep under-ground;
  •  If we can’t park close to your Septic Tank and have to lay-out lots of hoses (the additional distance slows pumping);
  • The sludge is exceptionally thick because the Septic Tank is overdue for an empty.

Additional Disposal Charges:

Our allowance of 3,000 Litres is more than ample for most Septic Tanks but if your Septic Tank holds more than this then we’ll charge the additional disposal fees at 10% on the quoted price per 1,000 Litres.

Health & Safety:

Our Operators require safe access to your Septic Tank, so please consider this and tell us about any potential hazards on your property (tricky driveways, pets, extra heavy Septic Tank lids etc.).  Also, our trucks carry 30 metres of hose, so please let us know if you think we’ll need more to reach your Septic Tank. Our operators are experienced and careful but occasionally pathways, driveways, underground services, lawns and gardens can be damaged by the weight of the truck.

Please note that this type of damage is at the customer’s own risk.

After Hours Call-Outs:

Emergency Work carried out outside normal working hours of Monday to Friday 7:30 am – 5:00pm, weekends or public/provincial holidays will incur an additional call-out fee. Please contact us to enquire about the charges.


Invoices are emailed to you after completion of the job. Payment in full is required within 7 days after completion of work.

Payment can be made via direct credit to our bank account. Cheques made out to Sepclean Ltd or Nelson Marlborough Waste can be posted to PO Box 3389, Richmond 7050.

Any account queries please contact our office or email our Accounts Mailbox on accounts@nmwaste.co.nz

Nelson Marlborough Waste


01 0702 0278672 00         Nelson Area

01 0702 0278672 01         Blenheim Area


We really appreciate you using our services and genuinely value your loyalty and feedback.