Blocked Drains in Kew, Barnes and East Sheen: Riverside Clay and Old Terraces

Three Villages, One Set of Drains

Kew, Barnes and East Sheen like to think of themselves as three separate places, and above ground they are. Below ground they share a geology, a housing era and a set of drainage habits, and from the back of our van they are one problem with three postcodes.

If you have found this page because something is backing up right now, call 07700 137648 and we will come. If you want to understand why it keeps happening, read on. We find this stuff genuinely interesting, which we accept is a minority position.

What Is Under the Pavement

All three areas were built out in the decades either side of 1900, on terraces and semis that drain through salt-glazed clay pipe to a sewer under the road. Clay pipe is good pipe. The joints are the weakness: every 600mm or so there is a collar, and every collar is a place the ground can move it.

The ground here does move. Kew, Barnes and the lower half of Sheen sit on low riverside clay inside a bend of the Thames. The water table is never far below the lawn, it rises every winter, and a hundred winters of that rhythm has nudged the joints out of true. A nudged joint does two things: it lets silt in from the backfill, and it lets water out, which is the invitation the trees have been waiting for.

The Trees

Kew has plane trees, Barnes has the common and the willows along the Beverley Brook, and East Sheen has a century of mature gardens full of limes and fruit trees. Every one of them is looking for water, and a weeping clay joint is the warmest, wettest thing underground. Fine roots go in, thicken, catch everything that passes and build a mat. The toilet gurgles, the bath slows, and one morning the gully lifts its lid.

Rodding a root mat clears it for a season. Jetting clears it for a year or two. Cutting the roots and lining the joint clears it for good, and on camera the difference between those three is obvious.

The Shared Run Problem

This is the local speciality. A lot of terraces in all three areas drain through a single run before it reaches the sewer, so your waste passes under next door’s garden, and theirs passes under yours. When it blocks, the house nearest the obstruction floods first and the house that caused it may never know.

The rules are simpler than people expect. A pipe serving only your house inside your boundary is yours. A pipe carrying more than one property, or running outside your boundary, is a lateral drain and belongs to Thames Water, which means they clear it for free. Our guide to whose drain it is, Thames Water or you goes through it with examples, and a CCTV survey settles the question with footage rather than an argument over the fence.

What to Try Before You Call

1. Stop using the affected fixtures. Every flush compacts the blockage.
2. Lift the nearest outside gully grate and clear leaves, silt and grease from the trap by hand. In Barnes after heavy rain this alone fixes a surprising number of calls.
3. Check whether more than one fixture is affected. One slow sink is a trap problem. A gurgling toilet plus a slow bath is the main run.
4. Do not pour chemical unblocker into a clay drain. It does nothing to roots or silt and we would rather not meet it when we open the chamber.

When It Is Time to Call

If the gully is overflowing, foul water is appearing anywhere it should not, or two or more fixtures are backing up, the blockage is in the run and needs jetting from the chamber. Call 07700 137648 at any hour. We arrive with jetting and camera kit on the same van, so if the clear reveals a cracked joint we can show you the footage there and then and talk about lining it.

One more local note. The same riverside ground that moves your drains also lets water into period houses from other directions, and a damp cellar or a wet floor near the river is not always a drain. Our sister plumbing firm Emergency Plumbers TW explain why period homes in Richmond and Twickenham are prone to leaks, and if your problem turns out to be theirs we will say so.