Mountainous areas are typical water sources for lowlands. These areas are also described as headwater areas or water tower (e.g. in East Africa). In general, they do not underlay any specific protection laws despite the scientifically proven fact of providing most of the fresh water.
The effect of headwater areas are:
- rainfall increase due to raising altitude
- mountainous areas are rarely used for agricultural activities; rainwater easily infiltrates and percolates – contribution to groundwater recharge
- surface runoff is collected by stream and rivers; due to little population density, the collected water is of good quality
- mountains release the water permanently throughout the year and thus contribute to water security downstream
These effects are only persistent as long as the natural environment of headwater areas are not changes and do not underlay anthropogenic and unsustainable activities. However, in Kenya the headwater areas are accepted as the most value water resources and are protected by law (Kenyan Water Act 2003).