i much materials i need for a french drain?

[dale]

hi there i need to put in a french drain to stop water flowing over a large tarmaced area. and i haveing problem working out how much materials i need to order .the trench is going to be 75m long x1.5 wide x1.5 deep aprox.going to 2 soak awys at each end as there is a high water table i was thinking of makeing it realy wide to compansate the lack of depth i was thinking about 5m x 5m x 2m.if any one can help me i would be gratefull ..thank you..[/list]

[TheDoctor4]

Please see our drainage projects section. It includes a couple of French drain-related articles as well as a number of related guides.