External drains carry water and waste away from the building. They include gullies, manholes and the pipes that run under your garden or drive, while leaves, silt, fat and tree roots are the usual causes of blocks. Each kind of block needs a slightly different fix.
Signs include water pooling around a gully, a manhole that fills or a smell near the drain. Yet often the first sign is a slow drain inside the house. For that reason, check the outside drains whenever indoor fixtures run slowly.
Ownership matters before you pay for work, since the owner pays for the fix. Read the section below, then see drain unblocking and drain cleaning for the wider picture. If the pipe is badly worn, a CCTV drain survey shows why.
Since ownership decides who pays, start there. The Sewerage (Scotland) Act 1968 defines a drain as a pipe inside the boundary that serves one building, while a pipe that serves more than one property is usually a sewer. Citizens Advice Scotland says Scottish Water maintains and repairs public sewers, and owners pay for their own drains.
Shared pipes need care because two views exist. Citizens Advice says owners of a shared pipe are jointly responsible, and the title deeds usually set out how to split costs. However, Scottish Water guidance says a drain that leaves your boundary, or joins drains from another property, becomes a public sewer.
So check your deeds first, then ask Scottish Water about any pipe beyond your boundary. If you rent from Dundee City Council, the council says to report a blocked or defective drain to its Customer Service Team or any Housing Office. Ask the council which route suits your tenancy.
Jobs usually start by lifting manhole covers and following the water. The first full chamber shows where the block begins. As a result, the search narrows to one stretch of pipe.
Leaves and silt come out by hand or with a tool. This step often restores the flow in a simple gully, although a long run needs more. Gloves and a hose are common.
Longer runs may need rods or a high-pressure jet, while a jet also cleans the pipe walls. See drain jetting for how it works. Ask which method suits your pipe.
Running water through the drain shows whether it flows freely. Roots, cracks or a sagging pipe may show up here, and these still need a camera check. Ask whether the engineer saw any sign of damage.
The engineer who takes your job runs a separate business, so the engineer sets the price, the arrival time and any guarantee. Use these questions to compare quotes, since answers differ from one engineer to the next. Write the answers down, because a written note helps if the job changes.
MyJobQuote lists outside drain unblocking at £80 to £150. Fantastic Services gives £80 to £250 for most unblocking jobs outside London. These are UK guide ranges, not Dundee quotes, so real prices may still differ.
Costs rise with a long run, a deep manhole or a hard block, so ask whether the price covers the whole run. Ask for the quote in writing before work starts, since the scope changes the price. Compare two quotes if the job looks large.
You are responsible for a drain that serves only your property. Scottish Water looks after public sewers, while a shared pipe depends on where it runs, so check your title deeds. Ask Scottish Water where the public sewer begins.
A gully is the grated drain at ground level that takes water from a downpipe or a yard. Leaves and silt fill its trap. Lift the grate, wear gloves, scoop out the debris and rinse with a hose. However, if water backs up in a manhole, stop and ask for help.
Yes. Roots seek out water while they grow, so they can enter through cracks and loose joints. They then grow inside the pipe until it blocks. A CCTV drain survey shows whether roots are the cause.
No fixed rule fits every property. Drains with trees nearby, or that have blocked before, may still need regular checks. Ask the engineer for advice after the first visit.