- larg est ▁trib ut ary ▁to ▁the ▁L ack aw anna ▁River . ▁ ▁Spring ▁Brook ▁begins ▁near ▁Y ost ville , ▁Pennsylvania ▁and ▁flows ▁ ▁to ▁its ▁confl u ence ▁with ▁the ▁L ack aw anna ▁River ▁in ▁Mo os ic , ▁Pennsylvania . ▁ ▁The ▁waters hed ▁of ▁ ▁Spring ▁Brook ▁waters hed ▁has ▁nine ▁named ▁trib ut aries ▁of ▁its ▁own , ▁counting ▁subt rib ut aries . ▁ ▁In ▁ 2 0 1 2 ▁Pennsylvania ▁American ▁Water ▁completed ▁improvements ▁cost ing ▁$ 2 7 . 4 ▁million ▁to ▁the ▁dam ▁which ▁contains ▁the ▁ 1 . 3 ▁billion - g all on ▁res er voir . ▁ ▁White water ▁ra ft ing ▁is ▁done ▁from ▁the ▁res er voir ▁to ▁Mo os ic . ▁It ▁is ▁a ▁medium ▁difficult ▁level ▁for ▁p add ling ▁for ▁those ▁who ▁are ▁not ▁ready ▁for ▁the ▁ro aring ▁rap ids ▁but ▁not ▁quite ▁a ▁beginner . ▁ ▁It ▁is ▁no ▁longer ▁accessible ▁to ▁the ▁public ▁since ▁the ▁res er voir ▁was ▁purchased ▁from ▁PA W C . ▁ ▁Before ▁that ▁time , ▁there ▁was ▁a ▁nature ▁trail ▁that ▁included ▁s ights ▁of ▁cre eks , ▁the ▁stream , ▁falls , ▁de er ▁and ▁other ▁small ▁animals ▁of ▁nature . ▁ ▁References ▁ ▁External ▁links ▁http :// www . lr ca . org / pages / n orth po cono / pages / spring bro ok fact sheet . htm ▁ ▁Category : Res er voir s ▁in ▁Pennsylvania ▁Category : Pro te