▁a ▁group ▁of ▁ill ust ri ous ▁Milan ese ▁citizens ▁led ▁by ▁Cat ell ano ▁C otta , ▁the ▁du ke ' s ▁administrator ▁for ▁the ▁salt ▁mon opol y . ▁The ▁project ▁a ims ▁to ▁devi ate ▁the ▁River ▁Add a ▁and ▁thus ▁build ▁a ▁canal ▁for ▁ir rig ation ▁and ▁to ▁feed ▁up ▁to ▁ 1 6 ▁mill ▁whe els . ▁The ▁design ▁included ▁a ▁water ▁int ake ▁position ed ▁just ▁below ▁the ▁castle ▁of ▁Tre z zo ▁sull ' Add a , ▁where ▁the ▁natural ▁course ▁of ▁the ▁river ▁narrow s , ▁therefore ▁producing ▁a ▁current ▁sufficient ▁to ▁guarantee ▁a ▁constant ▁flow ▁of ▁water . ▁The ▁canal ▁was ▁to ▁run ▁alongside ▁the ▁river ▁until ▁Cass ano ▁d ' Add a , ▁where ▁it ▁would ▁curve ▁away ▁in ▁a ▁south - w ester ly ▁direction ▁towards ▁Milan , ▁then ▁h ug ▁the ▁town ▁walls ▁of ▁In z ago , ▁turn ▁towards ▁Tre cel la ▁and ▁Mel zo , ▁and ▁finally ▁end ▁up ▁in ▁the ▁River ▁Mol g ora . ▁▁ ▁Because ▁of ▁the ▁political ▁situation ▁of ▁the ▁time , ▁nothing ▁happened ▁until ▁ 1 4 5 7 , ▁when ▁Francesco ▁S for za ' s ▁ed ict , ▁under written ▁by ▁Cic co ▁Simon etta , ▁marked ▁the ▁start ▁of ▁design ▁work . ▁The ▁project ▁was ▁seen ▁as ▁being ▁of ▁great ▁public ▁benefit : ▁since ▁the ▁war ▁between ▁Milan ▁and ▁Ven ice , ▁S for za ▁had ▁real ised ▁the ▁military ▁and ▁economic ▁potential ▁of ▁a ▁navig able ▁canal ▁in ▁an