1. if you are considering installing a drainage scheme in your garden the first item to address is how you remove the water from the garden. Its a point not many people consider or they figure they can get away by installing a soak away. A soak away is OK were the soil or sub soil is of such a structure were water will soak away over a few hours but in the case of a clay soil or a garden that floods its not going to help. The only choose is to connect your drainage system to an effective ditch or into the properties roof drainage system connecting to one of the houses down pipes through a silt trap to help prevent the system becoming blocked with silt.
2. The second key is that most garden drainage schemes are designed on an agricultural drainage system which are designed to allow the farmer to plough the area every year. In a garden situation with borders and lawns the drains often become capped and the water cannot reach the drain through an impervious soil layer often created by compaction. The answer is often to install sand slits which are designed to connect the surface with the drain even when the soil over the drain becomes compact.
For further advice on designing and installing a garden drainage scheme contact the GardenAdvice Team for advice and further information click here