Gardens & Drainage · Problem & repair
Garden drainage problems and water running towards the house
Water always goes downhill, and in a lot of gardens the lowest point is the back of the house. Once you know where the water is arriving from and where it can legally go, the engineering is usually straightforward.
The two questions that decide every drainage scheme are: what is the catchment area, and where is the outfall?
How to tell this is your problem
- Puddles that persist between rain showers
- Water tracking towards a wall or threshold
- Silt fans on paving showing the flow path
- A soakaway or gully that overflows
- Damp patches on external walls at low level
Repair or replace?
Deal with drainage before any new hard landscaping. Retro-fitting drainage under a finished patio costs far more than designing it in.
Repair options, cheapest first
- 01
Interceptor channel
A linear drain at the top of the fall catches water before it crosses the garden, connected to a suitable outfall.
- 02
Sized soakaway
A crated soakaway designed to the catchment area and sited the required distance from buildings and boundaries.
- 03
Re-grading and swales
Re-shaping the ground so water is directed to a planted or gravelled area that can absorb it. Often the least intrusive option.
- 04
Permeable hard surfaces
Replacing sealed paving with permeable construction reduces run-off at source rather than piping it away.
Why it happens
Levels falling the wrong way
Garden levels raised over time by decking, new patios or added topsoil can end up shedding water back towards the building.
Too much hard surface
Every square metre of paving or roof adds to what the remaining soft ground has to absorb.
Blocked or undersized soakaway
Soakaways silt up and lose capacity. Many were undersized for the area they serve in the first place.
Neighbouring levels
Water arriving from higher adjoining ground has to be intercepted at the boundary rather than dealt with at the house.
Cost and time on site
Indicative cost
Priced by run length, excavation depth and outfall type. Soakaway crates and muck-away are usually the significant items.
Typical duration
Most domestic schemes are two to five days.
Every quote is priced after seeing the site. We survey levels and outfall before designing any drainage - guesswork gets expensive.
Garden drainage problems: common questions
- How far from the house should a soakaway be?
- Guidance generally puts soakaways at least five metres from buildings. Ground conditions and local requirements vary, so confirm before building.
- Can I connect garden drainage to the foul sewer?
- No. Surface water must not go to a foul sewer without the water authority's approval - it causes overload and is not permitted as standard.
- Is water from my neighbour's garden my problem?
- Natural flow from higher ground is generally not something you can simply block, so most solutions intercept and manage it within your own boundary. Take advice on boundary specifics.
- Does a French drain need an outfall?
- Yes - a perforated pipe in gravel only works if the water it collects can get somewhere. Without an outfall it becomes a linear puddle.
Services that fix this
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