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Drain problems

A blocked drain is not a pleasant thing to wake up to. What’s worse is the realisation that it’s something that can generally be avoided by doing what I’m always talking about: maintenance.

The drainage system is easily forgotten because much of it is hidden away underground but, as with any element of a building, it should be checked at least once a year and, if necessary, flushed through. Any persistent problems should be throughly investigated.

Drains carry foul wastewater or rainwater or sometimes a mixture of both. They get blocked for all sorts of reasons but the most common are tree roots growing into them and inappropriate items being flushed away.

The first signs of trouble can be an unpleasant smell, an overflowing inspection chamber or gully, or a lavatory that doesn’t empty. If problems become severe and drains are fractured, damp may occur in the fabric of the building or there may be subsidence.

Small blockages inside the house can often be cleared by using a plunger. If you don’t have a plunger, and it’s the sink or bath that’s blocked, try repeatedly cupping your hand over the waste outlet and pressing up and down to create suction. It helps first to stick a piece of duct tape over the overflow outlet. Another option is to unscrew and clean out the waste trap; if the blockage is further down the pipe try ‘rodding’ it using a length of old electrical cable.

Outside, gullies may need to be bailed out and cleared by hand or with a plunger. Blockages in underground drains are frequently cleared by using a set of rods and the various attachments that come with them. These can be bought from a builders’ merchant or hired.

Once an inspection chamber is open it’s usually relatively easy to insert the rods and gently feed them along the pipe until the blockage is reached, at which point a hard prod may be required to shift the obstruction.

More difficult is the inspection chamber nearest the public sewer. Here there’s likely to be an interceptor trap; the cleaning ‘eye’, above the trap, will be sealed with a stopper which will have to be dislodged before the drain can be rodded to the sewer. Once blockages have been cleared, flush the system through thoroughly to check the water is flowing freely.

There are a number of important points to bear in mind when clearing drains:

  • Wear gloves and other protective clothing
  • When using rods, always remember to turn them in the direction that they screw together. If you don’t, they’re likely to become detached within the drain and you risk a much bigger problem
  • Think how you’re going to clean up afterwards. Have buckets of clean water and preferably a hose to hand
  • If you suspect there may be more serious problems, consider calling in a specialist company to carry out a survey of your drains using a CCTV camera to pinpoint blockages or damage

Image: Drain rods ©Roger Hunt