KITUI SAND DAMS

avoid filling the reservoir upstream. If on rock, it is advisable to cut a groove on therock to make good jointing of the rock and mortar. Investigations should be carried toavoid fractures and areas of weathering. This can be done by poring water on thesuspected weathered zones . The rock surface should be cleaned to avoid missing thefractures and areas of weakness. If clay or marrum is discovered, it should be dug intofor about 0.5 m to avoid seepage. After these conditions are met, the trench is readyfor dam setting and construction.Dam setting.This is done simultaneously with hydraulic design as earlier discussed .The followingdam parameters are determined and marked appropriately.H s , H d; Gf ; R ww; L ww; R dsb; L dsb; L d; L bf; W bf .CONSTRUCTION PROCESS.Construction starts with putting in place the reinforcement columns vertically in thetrench, which are followed by laying the foundation blinding slab. After this thesecond horizontal reinforcement layer is placed. This is flowed by the secondfoundation blinding slab and then the actual masonry structure comprising hard coreand mortar starts which what makes the dam.Proceedure.i) Placing Reinforcements.These are placed Vertically across the entire length of the dam at an interval of 2.5m.They are round bars of diameter of 12.5 mm and the length depends on the height ofthe dam. They consist of: -Their number in a dam is detertemined as follows,LdNo of columns = 12 −10E.g. If L d =10, Then No of columns = − 1 = 4 .2Marking the positions of the columns then measure the vertical depths and recordthem as follows.No 1 =2.5m, No 2=2.0m , No 3 = 3.0m.Marking of the reinforcement columns along the building line in the trench.0.40m2m 2m 2m 2m45