Shared Drain Blocked in Penge or Beckenham? Who Pays

If the blocked drain is shared by two or more houses, or lies outside your property boundary, it has been Thames Water’s responsibility since 1 October 2011, and you can report it to Thames rather than pay for it. If the drain only serves your house and the blockage is inside your boundary, it is yours. The quickest way to tell is to lift your inspection chamber cover: whether it is full or empty tells you roughly where the blockage is.

What changed in 2011?

Until October 2011, the drains behind a row of houses were a grey area. A pipe that ran behind five back gardens before reaching the public sewer belonged, in law, to the five owners jointly, and getting five neighbours to agree to pay for a drain clearance was nobody’s idea of a good evening.

On 1 October 2011 that changed across England. Drains that serve two or more properties, and drains that serve one property but run outside its boundary, were transferred to the water and sewerage companies. In Penge, Anerley and Beckenham that company is Thames Water. A drain that serves only your house, and stays inside your boundary, is still yours.

Why is this such a common question in Penge?

Penge and Anerley are full of Victorian terraces, and many of the larger houses along Anerley Road were converted into flats from the early 1900s onwards. The area has been part of the London Borough of Bromley since 1965. Victorian builders routinely ran one drain behind a whole terrace, picking up each house in turn before turning out to the sewer in the road. Then the conversions came, and a house that was one household became three or four, all on the same old pipe.

So in SE20, and in the older parts of Beckenham, a lot of drains are shared, and a lot of households are sharing them. The more people on a drain, the more likely it is that something goes down it that should not.

How can I tell whose blockage it is?

Thames Water’s own guidance gives the rule of thumb:

• It is likely to be yours if only your home is affected, your property does not share a drain, and there is no other flooding in the area.
• It may be Thames Water’s if the problem is outside your property boundary, or more than one property is affected.

Then there is the inspection chamber test. Most houses have at least one inspection chamber (a manhole with a metal or concrete cover) in the front or back garden, or under a path.

• Chamber full of water or waste: the blockage is downstream of it, between the chamber and the sewer. If that stretch is shared or runs outside your boundary, it is probably Thames’s.
• Chamber empty, but your toilet or sinks will not drain: the blockage is between your house and the chamber. That is usually your own drain.
• Your neighbour’s chamber is also full: strongly suggests a shared section, so ring Thames.

Thames adds a useful clue for houses converted into flats: if the upstairs is affected but downstairs is fine, the blockage is probably inside the building, not in the drain.

What should I do, step by step?

1. Stop using water in the house: no flushing, no washing machine, no showers.
2. Lift your inspection chamber cover carefully, using gloves, and look at whether it is full or empty.
3. Ask your neighbours whether their toilets and sinks are draining, and check their chamber if you can.
4. If the drain is shared or the blockage is outside your boundary, report it to Thames Water through its website or call Thames Water on 0800 316 9800.
5. If it is clearly your own drain, call a plumber or drainage engineer to clear it.
6. If sewage has come into the house, keep children and pets away from it, wear gloves, and photograph it for your insurer before you clean up.

What if Thames says it is mine?

It happens, usually when the blockage turns out to be on the single-property branch before it joins the shared run. A drainage engineer with a camera can show exactly where it is, and that footage is what settles a disagreement. If you have had the drain cleared privately and the camera shows the problem was on the shared section, keep the report.

How do I stop it happening again?

Thames Water’s advice is blunt: bin anything that is not pee, poo or toilet paper. That includes wet wipes marked “flushable”, cotton buds, sanitary products, kitchen roll and fat. In a converted Penge house, that message needs to reach every flat on the drain, not just yours. Fat poured down a kitchen sink sets hard in a cold Victorian clay pipe, and wipes catch on it.

If the same drain keeps blocking, it may be cracked, sagging or invaded by roots, which a camera survey will show.

What about Welling or Swanley?

The 2011 rule applies everywhere in England, so the same test works across our whole patch. Our guide to whether a blocked drain in Welling is yours or Thames Water’s walks through a 1930s semi rather than a Victorian terrace, which changes where the shared run tends to be.

Need a plumber now?

If your drain is yours and it is blocked, or a toilet is overflowing, Call 07868 281022. Tell us your postcode, which fittings will not drain, what the inspection chamber looks like, and whether the water is off. We clear blocked drains in Beckenham, Penge and Anerley, deal with overflowing toilets, and we agree the price with you before any work starts. More on our blocked drain service.