Clear a blocked outside drain safely: locate it, lift the cover, rod the blockage, flush it, then know when to call your water company.
OD-01Work out which drain is blockedLook for the symptom first: a gully that won't drain, water backing up in a sink or toilet, or a bad smell outside. Follow the pipe run from the fixture to the nearest gully or manhole cover in the garden or path. Knowing which drain serves which fixture saves you lifting the wrong cover.
OD-02Get set upPut on rubber gloves — drains carry waste water and you don't want that on bare skin. Line a bucket with a bin bag for the sludge and debris you'll pull out. Keep a hose or tap nearby for flushing later.
OD-03Lift the manhole or inspection coverFit a manhole key into the lifting holes and pull straight up, bending your knees rather than your back. If it's stuck, work a spade gently around the edge first — don't lever hard on plastic covers, they crack. Set the cover down away from the hole so you don't trip over it.
OD-04Find where the blockage actually isIf you have more than one manhole, lift the next one down the line towards the street. If the chamber nearer the house is full but the next one is empty or low, the blockage is between the two — that's where you need to work. This saves you rodding the wrong stretch of pipe.
OD-05Clear the gully or chamber by hand firstScoop out leaves, silt, fat and other debris from the gully grid or the bottom of the chamber before you rod anything. A lot of blockages clear at this stage alone. Bag the waste as you go rather than leaving it on the path.
1 each · Small trowel or scoop OD-06Rod the drainScrew a plunger or corkscrew head onto a rod and feed it into the pipe, adding rods one at a time as it goes further in. Push and turn each rod clockwise only — turning anticlockwise unscrews the joints and can leave a rod stuck in the pipe. Work it back and forth gently rather than forcing it.
1 each · Drain rod set (with plunger and corkscrew attachments) OD-07Flush it throughRun a hose or tap into the gully and watch the water level at the manhole or gully. If it drains away freely, the blockage has cleared. If it's still slow, go back and rod again — don't move on until the flow looks normal.
OD-08Clean up and put covers backRefit the manhole or gully cover firmly. Hose down the rods, trowel and bucket before you put them away, and give your gloved hands a good wash with soap afterwards even though you wore gloves. Bag any solid waste for the general bin — never the recycling.
OD-09Know when it's not your jobIf the blockage is beyond your boundary, or the drain is shared with a neighbour on its way to the public sewer, it's a 'lateral drain' — your water company is responsible for these, not you, since private sewers and laterals transferred to water companies in October 2011. Call them free rather than paying someone privately. If rodding hasn't shifted it and it's clearly on your own pipework, a professional with high-pressure jetting equipment is the next step.
RULESKNOW THE RULES
Shared drains and lateral drains connecting to the public sewer became the water company's responsibility under the 2011 transfer of private sewers — you don't need to fix or pay for these yourself.
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