Nairobi, July 17 -- The Aberdare Range is one of five water towers which are the single largest such sources for direct human consumption and industrial activities. It is situated in central Kenya on the Equator, stretching over 125km from Nyahururu in the north to Limuru in the south. At Limuru, subterranean tributaries converge to form Manguo Swamp which in turn feeds Ondiri and Rungiri wetlands further south in Kikuyu. Tributaries from both wetlands meet to form what becomes Nairobi River after Kikuyu Springs which was the first source of water supply to Nairobi Municipality in 1906.

Last week I was invited to a tree planting activity at Rungiri Dam which was created inadvertently in 1992 during the construction of the Uthiru-Rironi Roa...