by Ensures the drainage of every single drop of extra water from the system.
Drainage refers to the process and practices used to remove excess water from the soil surface and from the soil profile.
For the purpose of preventing surface water ponding and controlling runoff without causing erosion, surface drainage is the cheapest and easiest option in some cases. In this system, excess water from the soil surface is removed by flowing over the naturally or artificially sloping ground toward surface inlets, shallow ditches and grassed waterways.