The timely removal of excess water following heavy rainfall or local floods is important to avoid crop damage and build-up of water logging. The inability to remove excess rainfall runoff can be problematic in low lying areas or areas with a particular flat gradient.

In storm water drainage, before constructing dedicated storm water drainage systems a number of aspects should be considered:

•         Priority should be given to unblocking natural drains closed by roads and residential areas and make adequate cross drainage on new and old infrastructure compulsory.

•         Retaining runoff at source or diverting excess water where the gradient allows to recharge areas will have a double benefit: the runoff will be used beneficially and no downstream flooding problems will occur.

•         Besides capturing storm water, local dugouts in some cases may (in drier periods) also serve to lower groundwater tables and provide local freshwater storage.

Additional information

(semi) Natural unused areas

(semi) Natural unused areas

Agriculture

Irrigated