A grassed waterway is a wide, shallow grassed channel that can carry a large volume of water quickly down a steep slope. It can be crossed by lifting tillage equipment. The size of the waterway depends on the size of the area to be drained. Side slopes usually rise about 1 m for every 10 m horizontal distance. The waterway should follow the natural drainage path if possible.
Grassed waterways are shallow and easy to cross.
Some landowners produce hay on their waterways. Cross-section of a typical grassed waterway. The grass cover must be well established to handle high flows without erosion. A fast-growing cover crop, such as oats, provides initial, temporary protection for the waterway until the grass cover is established. Steeper portions of the waterway which are very susceptible to erosion can be protected by bio-degradable erosion control mats until the grass is established.