Drainage systems for waterlogged gardens and lawns

What's the best garden drainage system?

I have described the main Garden drainage systems here, the links are safe to use and do not lead to annoying adverts, but to my articles with more detailed information. 

For waterlogged lawns or flooding problems, the drainage systems described on this page or a combination will drain the water away. 

To have the work done for you see our services by clicking here   garden drainage 


Here are some of the more common reasons you may need to install a drainage system to drain the water away from your home or garden. Or in extreme cases protect your property from flooding.

  • Underground springs causing waterlogging  in the garden, 

  • Surface water draining into your garden from higher ground,

  • Rainwater lies for several hours in pools on the surface,

  • The ground or lawn is always soggy.

  • Footings for extensions redirecting water.

  • A neighbour is directing rainwater into the garden.

  • Flooding from a river.

French drain drainage system being laid under a lawn
French drain drainage system being laid under a lawn

Some drainage systems will be as simple as aeration of compacted ground. Aeration is simply forking over the surface of the compacted lawn to allow surface water to drain from the surface into the soil below. It's worth trying this before calling in the experts.  How to aerate 
 
Flowing water from a spring, rainwater flowing from higher ground or lying on saturated ground for more than three days will almost certainly need a garden drainage system installation that intercepts the water and directs it away into a  soak-away,   sump pit  or into the rainwater drainage system.  

Drainage system that is laid under the lawn and garden can typically be built using plastic drainage pipe, gravel French drains or a combination of gravel and pipes.
French drain system. 
Over the years, when they are installed correctly, a  gravel drainage system (French drain) installed below the surface, last longer and is the most effective drainage system laid under grass and is the land drainage method I use.  
French drainage takes about three days to install and the area will be usable within a few days. The gravel is laid into lined trenches dug in a "herring-bone" pattern to drain the complete area.
 
The French drain gravel drainage system is described here lawn and garden drainage.
After the French drain system has been installed the area is covered with grit sand and aerated and can be seeded or returfed. More information about this simple drainage system and DIY tips can be found on my   D.I.Y. drainage pages. 

Sump and Pump method.
When using plastic pipes or  French drainage  to drain a wet soggy garden, the water needs to be  dispersed away from your garden. Providing the slopes are all flowing in the right direction this can be a soak away, ditch or the surface water drainage system. 
 
Tempting as it may be, surplus water should never be channeled to terminate in your neighbours garden.  If the slopes are flowing in the wrong direction you will need to install a Sump and Pump  systems, that works by collecting and pumping the water to a discharge point.  How to install the sump and pump is explained on my drainage sumps and pumps page.
 
A BUND defense for gardens at risk of flooding.
Flood barriers can be constructed to stop or at the very least slow down flood water flooding your garden.  The Bund described in this article is made from clay based soil forming an embankment, acting as a flood defense to protecting domestic gardens from flooding. More here constructing a bund

For small localised wet patches and soggy areas, these drainage tips may help

  • Puddling. When rainwater water lies on the surface of a lawn for more than a couple of hours  after rain its probably caused by compacted soil or clay, made worse by dips and humps in the surface of the lawn. Compacted soil puddling is fairly easy to sort out by digging holes with a garden fork or even a crowbar over the whole of the affected area and filling the holes with coarse sand or gravel. If the problem is caused by clay, this wont work, check out these pages,  improving clay soil 
  • Soggy area or spongy lawnIf you have a soggy area that is permanently wet it can nearly always be dried out by digging out a soak away 1m square and depending on the severity up to 1m deep or if the sogginess is spread over a wider area, dig a soak away trench through the area about 18 inches wide and as deep as you can. Half fill the trench or soak away with clean rubble topped with 20 to 30ml gravel and finished with about 6 inches of top soil.  You will end up with quite a lot of surplus soil, if its clay you will need to get rid of it, if its good loamy soil use it to raise your borders.
  • Leveling dips that catch surface waterIf your lawn has good drainage properties but puddles on rainy days, mark out the dips with bamboo canes, wait until the lawn dries out, fork over the area and fill the dips with Grit sand. Its important not to smother the grass, so leave the tips of the grass poking through the sand. This process can be repeated over the growing season, until the whole lawn is level and free of hollows and dips.
  • Raised beds for small soggy areas. If the wet soggy area is limited to a small part of the garden, raising the area by adding topsoil can work. Raised beds are the best way and can be made from almost any material available, my raised garden bed explains how. If the whole garden is waterlogged, raising the level with soil does not work you would be creating a swamp. raising the whole garden can work if done correctly Before getting talked into creating one big bog read this  Raising flooded garden
  • Bog gardens for low wet areas.Turning the unusable swamp in a low part of your garden into a colourful bog garden planted with Bog plants that actually thrive in soggy soil works and is explained on my bog garden page.
  • Using permeable paving. Permeable paving allows water to drain through and back into the ground instead of diverting it to where it will cause a wet soggy area or as with tarmac driveways that slope away from the house, onto the road causing dangerous ice traps in winter, not very neighborly. Block pavers are a good example of permeable paving.
Linear Drainage channels
 
Linear drainage channels are the best rainwater drainage systems to protect garages situated at the bottom of a sloping driveway, they catch rainwater and direct it away from the garage to a drainage point. 
Linear drains are made from polymer concrete or plastic and fitted with plastic or metal grating over the top. I use the Aco channels available from most builders merchants or now from amazon.
Linear drainage systems  are easy to fit into existing driveways and patio paving by cutting out a gully large enough to fit the channels in. Corner units and other fittings including T-junction units are available with most makes of linear drainage systems.

Perforated plastic pipes for laying underground drainage system.

 
Modern plastic land drain pipes are installed in much the same way as gravel drains. The perforated pipes are laid, on a bed of gravel in trenches that slope to a soakaway or drain system and covered in gravel.  Soakaways do not work in heavy clay and should be connected into the rainwater drainage system, not terminating under your neighbours fence.

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