▁allowed ▁for ▁the ▁sale ▁of ▁the ▁Canadian ▁Ent it lement ▁to ▁down stream ▁U . S . ▁power ▁authorities ▁( B PA ). ▁ ▁Inst ru ments ▁of ▁rat ification ▁were ▁ex changed ▁and ▁the ▁treat y ▁was ▁implemented ▁on ▁ 1 6 ▁September ▁ 1 9 6 4 . ▁ ▁United ▁States ▁ ▁Starting ▁in ▁the ▁ 1 9 3 0 s , ▁the ▁United ▁States ▁constructed ▁d ams ▁on ▁the ▁lower ▁Columbia ▁River ▁for ▁power ▁generation , ▁flo od ▁control , ▁channel ▁navigation , ▁and ▁ir rig ation ▁in ▁Washington ▁as ▁part ▁of ▁the ▁Columbia ▁Bas in ▁Project . ▁Dam ▁construction ▁on ▁the ▁American ▁side ▁of ▁the ▁border ▁thus ▁began ▁prior ▁to ▁the ▁entry ▁into ▁force ▁of ▁the ▁Columbia ▁River ▁Tre aty . ▁There ▁were ▁various ▁plans ▁put ▁forward ▁in ▁the ▁early ▁ 2 0 th ▁century ▁for ▁major ▁d ams ▁on ▁the ▁Columbia , ▁many ▁focused ▁on ▁ir rig ation , ▁but ▁development ▁did ▁not ▁begin ▁in ▁earnest ▁until ▁the ▁ 1 9 3 0 s . ▁During ▁the ▁Great ▁De pression , ▁the ▁US ▁Federal ▁Government ▁provided ▁the ▁imp et us ▁for ▁construction , ▁as ▁part ▁of ▁the ▁New ▁De al ▁make - work ▁program . ▁Const ruction ▁on ▁the ▁B onne ville ▁and ▁Grand ▁Cou lee ▁D ams ▁began ▁during ▁this ▁period , ▁but ▁government ▁invol vement ▁in ▁Columbia ▁dam ▁construction ▁has ▁continued ▁through ▁to ▁the ▁present . ▁ ▁The ▁long ▁range ▁plans ▁for ▁American ▁development ▁of ▁the ▁Columbia ▁for ▁hydro elect ric ity ▁came ▁together ▁in ▁the