Rainfall Type

Drainage Massiveness

On the other hand, drainage basins with penetrable rock and soil types are likely to have lower drainage density. The drainage density index, which is a measure of total extent of watercourses as seen on aerial pictures per unit area, was evaluated for multiple watersheds in a bid to relate land-use alterations and hydrologic and water quality reactions to drainage patterns.

Soil Variety

Clay soils and silts have small porous areas allowing but just a little seepage while sandy soils have fairly larger voids or air spaces between individual particles allowing higher seepage, additional drainage advice from Drainage Hull (drainagehull.uk).