garden drainage?

patmac1974

Hi all.
Was hoping to get some advice on an gffective way to drain my garden.
About 4 years ago i installed a very large deck and since then each winter my garden turns into a marsh land. I understand that since installing the deck the rain water has nowhere else to go except onto the lawn.
The main problem is that i have very heavy clay soil which never seems to dry out ,and when it does it forms cracks all over. Its a pretty small garden, modern semi d, about 20 feet wide by 20 ft long. Am at the end of my rope here, please help.

gollyitsolly

I dont think decking should cause the garden to flood. Is there plastic sheeting or a weed barrier under it? Perhaps it needs to be punctured with holes as the water might be sitting on it. Is your garden on a slope ? Are you living in known flood area? You can install rainwater gullies around paving which run into a drain but Im not sure if you can do them around a lawn.

patmac1974

The spacing between my decking boards has closed up tight so all the water runs off the end of it onto the lawn. the garden slopesdown slightly but the clay soil is so heavy cater just lodges and takes ages to drain. dug a 2x2x2 hole to plant a tree and its still full of water 1 week later

k123456

Try a French Drain, or might be a case of digging in lots of gravel into earth
http://www.gardenadvice.co.uk/howto/garden-build/frenchdrain/

If the deck boards are butted up against each other, can you remove boards and rescrew with correct gap (5mm)

gollyitsolly

Yeah, the boards swell when wet. People forget to leave an expansion gap. Is it possible to lift all the boards and reset them? A long and tedious job but worth it in the end. Maybe you could get some friends to help you. Also if you can get a few trees to grow round the garden the roots will help to soak up some of the water.