▁the ▁United ▁States ▁Census ▁Bureau ' s ▁ 2 0 0 8 – 1 2 ▁American ▁Community ▁Survey , ▁ 1 1 . 2 % ▁of ▁workers ▁in ▁Cor v all is ▁b icy cle ▁to ▁work . ▁ ▁The ▁city ▁of ▁Cor v all is ▁is ▁ranked ▁third - high est ▁among ▁' small ' ▁U . S . ▁cities ▁( with ▁populations ▁under ▁ 2 0 0 , 0 0 0 ) ▁for ▁b icy cle ▁commut ers , ▁behind ▁Key ▁West , ▁Florida ▁( 1 7 . 4 ) ▁and ▁Davis , ▁California ▁( 1 8 . 6 ). ▁ ▁Air ▁ ▁Cor v all is ▁Municipal ▁Airport ▁serves ▁private ▁and ▁corpor ate ▁aircraft . ▁The ▁closest ▁commercial ▁air ▁service ▁is ▁available ▁at ▁Eug ene ▁Airport , ▁, ▁or ▁Port land ▁International ▁Airport , ▁. ▁ ▁Br id ges ▁ ▁Van ▁Bur en ▁Street ▁Bridge ▁ ▁Util ities ▁ ▁Water ▁ ▁The ▁city ' s ▁water ▁system ▁has ▁two ▁water ▁treatment ▁plants , ▁nine ▁processed ▁water ▁res er voir s , ▁one ▁raw ▁water ▁res er voir , ▁and ▁some ▁ ▁of ▁pipe . ▁ ▁The ▁system ▁can ▁process ▁up ▁to ▁about ▁ ▁of ▁water ▁per ▁day . ▁ ▁The ▁Rock ▁Creek ▁treatment ▁plant ▁processes ▁water ▁from ▁sources ▁in ▁the ▁ ▁Rock ▁Creek ▁Municipal ▁W aters hed ▁near ▁Mary s ▁Pe ak . ▁ ▁The ▁three ▁sources ▁are ▁surface ▁streams , ▁which ▁are ▁all ▁trib ut aries ▁of ▁the ▁Mary s ▁River . ▁ ▁Rock ▁Creek ▁has ▁a ▁processing ▁capacity