What slope percentage is denoted by medium surface drainage without cover?

The designation of medium surface drainage without cover corresponds to a slope percentage that typically ranges between 2-9%. This range indicates that the land has a gentle to moderate incline, which is significant for surface drainage characteristics. At this slope percentage, water moves relatively slowly across the surface, allowing for effective drainage while still retaining soil moisture levels that are usually favorable for plant growth.

In contrast, slopes categorized as lower or higher than this range would reflect different drainage conditions. For example, a slope of 0-5% would indicate very gentle drainage, while slopes of 5-14% or 9-12% would suggest more rapid drainage, which can lead to different soil moisture retention and drainage dynamics. Therefore, the 2-9% range describes a condition where medium surface drainage is most applicable, making it the correct choice.