▁from ▁Dur ham , ▁and ▁some ▁stayed ▁on ▁to ▁run ▁the ▁works , ▁including ▁Stanley ▁Ald ridge , ▁who ▁had ▁been ▁the ▁Engine er , ▁and ▁became ▁the ▁General ▁Manager ▁of ▁the ▁L ayer ▁works . ▁ ▁J oint ▁projects ▁ ▁Although ▁the ▁South end ▁Water works ▁Company ▁and ▁the ▁South ▁Es sex ▁Water works ▁Company ▁did ▁not ▁formally ▁un ite ▁until ▁ 1 9 7 0 , ▁they ▁co - oper ated ▁on ▁two ▁major ▁projects ▁prior ▁to ▁that ▁date . ▁These ▁were ▁the ▁construction ▁of ▁H anning field ▁Res er voir ▁and ▁the ▁E ly - O use ▁to ▁Es sex ▁Transfer ▁Sch eme . ▁ ▁The ▁construction ▁of ▁H anning field ▁Res er voir , ▁which ▁was ▁author ised ▁by ▁the ▁H anning field ▁Water ▁Order ▁ 1 9 5 0 , ▁and ▁began ▁in ▁ 1 9 5 1 , ▁was ▁a ▁joint ▁vent ure ▁between ▁the ▁two ▁companies . ▁It ▁was ▁built ▁in ▁the ▁Sand on ▁Valley , ▁to ▁the ▁north ▁of ▁W ick ford , ▁and ▁covered ▁the ▁ham let ▁of ▁Pe as down . ▁A ▁ ▁mass ▁earth ▁dam ▁with ▁a ▁p ud d le ▁cl ay ▁core ▁was ▁built ▁across ▁the ▁north - east ▁edge ▁of ▁the ▁site , ▁and ▁a ▁new ▁ ▁pipeline ▁was ▁built ▁from ▁the ▁Lang ford ▁p ump ing ▁station ▁to ▁supply ▁the ▁res er voir . ▁The ▁main ▁contract ors ▁for ▁the ▁project ▁were ▁W & C ▁French , ▁and ▁it ▁took ▁around ▁ 5 ▁years ▁to ▁complete , ▁with