Water Pooling on Your Driveway: Why It Happens and How to Fix It

Water pools on a driveway for one of four reasons: the surface was laid without enough fall, part of the base has sunk, a drain or soakaway has blocked, or the surface is sealed and the water simply has nowhere to go. Most of them can be diagnosed in ten minutes during heavy rain. A blocked channel is a quick clear; a sunken base or the wrong falls usually mean cutting out and relaying the affected area.

The likely causes, most common first

1. Not enough fall, or the fall goes the wrong way

A drive needs a gentle slope so water runs off it. Pavingexpert recommends a minimum fall of 1:80 on tarmac, with 1:40 to 1:60 preferred. In plain numbers, 1:80 is 12.5mm of drop for every metre, and 1:40 is 25mm per metre. Drives laid dead flat, or "by eye" without levels, hold water in shallow sheets after every shower, and the levels are the first thing we check when asked to look at driveways in Wolverhampton that hold water. A drive that falls towards the house is worse, because the water ends up against the wall or under the front door.

2. A sunken patch in the base

A low spot that was not there when the drive was new almost always means something underneath has moved. The usual culprit is a sub-base that was too thin or not compacted in layers, so the wheel paths settle under the car. Soft spots over old trenches, tree roots that have since died back, and clay that shrinks in dry summers all do the same. On tarmac you see a shallow dish where the car parks; on concrete, a crack with one side lower than the other.

The sub-base is the part of a drive you never see, and it decides whether this happens. Our guide to MOT Type 1 sub-base explains what a proper one involves.

3. A blocked channel drain, gully or soakaway

If the drive has a channel drain across the entrance or by the garage, leaves, silt and moss will fill it eventually. Water then sits along the line of the drain instead of in it. If the channel is clear but still backs up, the problem is further down: a blocked pipe, or a soakaway that has silted up or sits in clay that no longer takes water.

4. A sealed surface with nowhere to drain

Standard tarmac and pattern imprinted concrete are not permeable. If the falls take the water to a kerb with no drain, or to a corner bounded by walls, it pools there. The same happens when resin is laid straight over old tarmac or concrete: the resin layer is porous, but the dense base underneath is not, so water passes through the top and then sits.

Permeable surfaces can also slowly lose their drainage if soil and silt wash into them. The government's front garden guidance recommends brushing permeable surfaces and keeping soil and garden run-off off them for that reason.

What you can check yourself

Go out during heavy rain and watch where the water goes. You will learn more in five minutes than from a dry drive.

• Where does it collect? One dish-shaped patch points to settlement. A strip along the house or a wall points to falls.

• Is the drain working? Lift the channel grating and look. If it is full of leaves and silt, clear it with a trowel and flush it with a hose.

• Where do the downpipes go? A downpipe discharging straight onto the drive can overwhelm a small channel.

• How deep is it? Lay a long straight timber or spirit level across the low area. A few millimetres of film that dries in an hour is a nuisance. A puddle you have to step around, or ice that forms in the same place every winter, needs fixing.

Fixes, from cheapest to most involved

Clear the drains. If the channel or gully was blocked, clearing it may solve everything. Do it each autumn after the leaves fall.

Add a channel drain. Where water gathers at one edge, a channel drain across the low point can collect it and carry it to a soakaway or an existing surface water drain. One of our own projects, a tarmac driveway with new drainage in Finchfield, involved fitting a new drainage system where there had been none, alongside 16 tonnes of Type 1 MOT sub-base.

Cut out and relay the low area. A sunken patch on tarmac or resin can be cut out, the base made good and compacted, and the surface relaid to the right level. The repair will show as a join, so on a large or prominent area it is sometimes better to resurface the whole drive.

Regrade or relay. If the whole drive was laid with the wrong falls, no patch will fix it. The surface has to come up and be relaid on new levels, sometimes with a permeable surface such as resin bound on a new porous base so the water goes down rather than across.

When the drive slopes towards the house

This is the case to deal with first. Water standing against a wall can push damp into it, and pooling at a door threshold can get inside. Pavingexpert's guidance is that paving next to a house should sit at least 150mm below the damp proof course, with no surface water left to lodge or run against the masonry. Where the levels cannot be changed, a channel drain along the front of the house, falling to a soakaway or drain, is the usual remedy.

If water runs off your drive and over the pavement, the council can also step in: section 163 of the Highways Act 1980 lets the highway authority or local authority serve notice requiring you, within 28 days, to install channels, gutters or downpipes to stop surface water flowing from your property onto the footway, so far as is reasonably practicable.

Fixing pooling on driveways in Wolverhampton

With an existing drive we always start with the drainage, a habit from over 25 years of drives around Wolverhampton and the Black Country. On a visit we check the levels, lift the drains and tell you whether it is a clear-out, a channel, a patch or a relay. If it does turn into a new drive, our driveway cost guide explains what moves the price, and you can book a free visit whenever suits.