Joseph Lokapel, quenches thirst from Mworwongar water pan in Kacheliba constituency. [File, Standard] In many neighbourhoods in Nairobi, you will hardly fail to come across the ubiquitous yellow 20-litre jerricans stacked high on a pushcart operated by water vendors. Water vendors have become a vital part of life in such neighbourhoods where taps run dry more often than not. As Nairobi continues to experience rapid population growth, it is struggling to keep up with the increasing water demand. Water rationing has become the norm in many parts of the city. In some estates, residents go for days without running water.…