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How to look after your septic tank to prevent pollution

05 March 2024 9:22

 | NI Water News

If your house is not connected to an NI Water sewer it is most likely discharging wastewater into a septic tank. It is important to look after your septic tank to ensure it is operating correctly to prevent pollution to the water environment. It can be costly to repair a failed septic tank, so good ongoing maintenance is essential. Below are some tips to help you maintain your septic tank.

Firstly, you will need to register your septic tank with DAERA if you have not already done so. To ensure your septic tank is in good working order, perform these checks regularly:

  • Check the drains around your house. Are they slow at clearing or are toilets blocking up? This could indicate your septic tank is full or the soakaway is blocked.
  • At the tank, make sure the cover is accessible. There should not be a smell from the tank. If the tank needs to be emptied, it may start to leak.
  • Check the discharge pipe for appearance and odours. A smelly or dark discharge pipe indicates a likely problem. I This could be caused by a build-up of sludge, blocked pipes, or too many chemicals being added to the tank which have killed the bacteria required for the treatment process. Get it checked by a specialist if you see any of these problems.
  • If you find fungal growth such as slime in the watercourse or smell odour coming from a nearby watercourse, it may be that your septic tank is releasing untreated sewage. Check the tank and pipes for any signs of damage and contact a plumber to fix the problem.
  • Plant trees and shrubs well away from your septic tank, as the roots can block up soakaways and drains.

If you have not emptied your septic tank in the last year, perform the above checks immediately. If the sludge level in it is too high, it will cause leaks and a risk of poor quality discharge to enter the environment near your house. If you are in any doubt, get your tank de-sludged. NI Water provides this service for free (1 free de-sludge per year, subject to access to septic tank) and will carry out the de-sludge within 12 working days of the request. This is not a full empty of the tank but will remove 4500 litres of sludge from the base of the tank. It is important not to fully empty older tanks as the scum layer could be disturbed. Some sludge should remain so that the waste treatment process can continue.

There are also ways to maximise the life of your septic tank and reduce its effect on the environment:

  • Have your septic tank emptied regularly - record any dates of maintenance/ emptying
  • Don’t drive over the soakaway or build anything above it (concrete or tarmac)
  • Only use household cleaning products labelled as  ‘suitable for septic tanks’, ‘environmentally friendly’ or ‘low phosphate’
  • Use a sink strainer to stop solids going down waste pipes
  • Use less water by flushing less or using a dual flush toilet
  • Only flush the 3 P’s (pee, poo and paper) down toilets
  • In the kitchen, do not pour grease or cooking oil down the sink

For more information or to book your de-sludge go to:

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