. A . ▁County ▁flo od ▁control ▁was ▁first ▁founded ▁in ▁an ▁effort ▁to ▁control ▁the ▁wild ▁waters ▁of ▁the ▁Ar roy o ▁Sec o ▁and ▁Charles ▁L umm is ▁founded ▁the ▁Ar roy o ▁Sec o ▁Foundation ▁in ▁ 1 9 0 5 ▁for ▁the ▁purpose ▁of ▁pres erving ▁recre ational ▁use ▁and ▁habitat , ▁residents ▁in ▁Los ▁Angeles ▁and ▁Pas ad ena ▁contributed ▁gener ously ▁to ▁efforts ▁to ▁buy ▁up ▁open ▁space ▁in ▁the ▁great ▁can y on ▁to ▁protect ▁for ▁future ▁gener ations . ▁ ▁There ▁has ▁been ▁a ▁series ▁of ▁studies ▁conducted ▁to ▁assess ▁and ▁improve ▁the ▁management ▁of ▁the ▁Ar roy o ▁Sec o ▁W aters hed . ▁ ▁These ▁include : ▁ ▁Rest oration ▁goals ▁ ▁Rest ore ▁full ▁flo od ▁control ▁functions ▁in ▁the ▁Ar roy o ▁Sec o ▁area . ▁ ▁Better ▁manage , ▁optimize , ▁and ▁con serve ▁water ▁resources ▁while ▁impro ving ▁water ▁quality . ▁ ▁Im pro ve ▁regional ▁park ▁recre ational ▁opportun ities ▁and ▁enh ance ▁nature ▁reserve ▁open ▁space . ▁ ▁The ▁rest oration ▁efforts ▁are ▁being ▁carried ▁out ▁by ▁the ▁County ▁of ▁Los ▁Angeles ▁and ▁local ▁cities , ▁primarily ▁the ▁City ▁of ▁Pas ad ena . ▁ ▁Jet ▁Prop ulsion ▁Labor atory ▁- ▁NASA ▁Early ▁ro cket - engine - testing ▁began ▁in ▁the ▁Ar roy o ▁Sec o ▁in ▁ 1 9 3 6 ▁and ▁this ▁led ▁to ▁the ▁establishment ▁of ▁the ▁Jet ▁Prop ulsion ▁Labor atory ▁( J PL ) ▁at ▁the ▁mouth ▁of ▁the ▁Ar roy