Recurring pipe problems – why a pipe keeps blocking up


Causes of a blocked drain

If there are ongoing issues with your pipes and you are experiencing symptoms such as a gurgling toilet, slow draining sinks, odours, the toilet not flushing or if sewage is backing up, have a plumber use a drain camera to inspect the pipe to determine the cause. Some possible reasons may include:


  • Tree roots inside the pipework
  • A dislodged joint where one section of pipe meets the next
  • Broken pipe
  • A belly in the line (sunken line) caused by ground movement or incorrect installation
  • A foreign object in the pipe, for example a child’s toy or nappy
  • ‘Flushable’ wipes
  • Fat or grease build up or food scraps


These will all catch debris such as toilet paper, as sewage waste flows down the sewerage line.



Tree root blockages will cause ongoing issues with drains and pipes. Pipe relining is a permanent way to stop tree root infiltration.


How to solve recurring pipe problems

Depending on the source of the problem, your pipes may need relining or they may simply need a good clean with a high pressure jet rodder.


Tree roots are able to enter sewerage and storm water pipes through any gaps such as a breakage or loose joints. The roots seek out moisture and nutrients to live and unfortunately sewer and stormwater pipes have favourable conditions they thrive on. Once they enter through a crack, they grow and can cause further damage.


A specialised plumber is able to fix broken sewerage and storm water pipes where tree roots have entered by relining it (a no-dig pipe repair option). First the pipe needs to be cleaned so the extent of the damage can be assessed and the tree roots removed. Relining involves inserting a large sock coated with resin inside the damaged area/s of pipe. The sock is then inflated inside the pipe and the resin sets hard and forms the new pipe work. This means the tree roots are no longer able to penetrate the repaired pipe, which means no more blocked drains.


This method is extremely practical as it does not require your landscaping or concrete driveway to be dug up. It is a minimal disruption alternative and it can usually be completed in a day. It is often a better alternative to excavations as they can be costly both financially and time wise. Relining is also a better fix than digging a pipe up. Tree roots will always find their way back into a pipe which has been dug up and repaired as the old and new pipe are joined with a flexible joint that is easily penetrated by tree roots.


If there is a belly in the line, the pipe will need to be dug up and replaced for a permanent fix. Instead of the pipe being straight, it dips down and back up again, making it hard for anything to pass through without becoming stuck. Pipes are laid falling downhill; they are not made for waste to travel back up a dip in the line. Relining takes the shape of the existing pipe so unfortunately it is not suitable to be used in this case. Regular flushing of the line may assist in keeping them clear. This can be done by filling the bathtub for instance and then letting it drain out.