For good drainage on a grassy surface, what is the minimum slope required?

For optimal drainage on a grassy surface, a minimum slope of 2% is necessary to ensure that water flows away from the area effectively. A slope of 2% means that for every 100 units of horizontal distance, there is a 2-unit vertical drop, promoting proper water runoff and preventing pooling or flooding.

A slope of less than 2% may not provide sufficient gravity assist, potentially leading to stagnant water, which can cause various issues such as erosion, soil compaction, and the proliferation of pests and diseases. While steeper slopes, such as 3% or 4%, can offer even better drainage, they may pose challenges for certain land use considerations, like erosion control, maintenance, and the playability of the grassy surface.

Thus, a 2% slope strikes a balance between effective drainage and manageable maintenance for grassy areas.