: V eh icles ▁introduced ▁in ▁ 2 0 1 0 <0x0A> </s> ▁Gast ine au ▁Channel ▁is ▁a ▁channel ▁between ▁the ▁main land ▁of ▁the ▁U . S . ▁state ▁of ▁Al aska ▁and ▁Douglas ▁Island ▁in ▁the ▁Alexander ▁Arch ip el ago ▁of ▁sout he astern ▁Al aska . ▁It ▁separ ates ▁June au ▁on ▁the ▁main land ▁side ▁from ▁Douglas ▁( now ▁part ▁of ▁June au ), ▁on ▁Douglas ▁Island . ▁The ▁first ▁European ▁to ▁sight ▁the ▁channel ▁was ▁Joseph ▁Wh id bey ▁early ▁in ▁August ▁ 1 7 9 4 , ▁first ▁from ▁the ▁south ▁and ▁later ▁from ▁the ▁west . ▁It ▁was ▁probably ▁named ▁for ▁John ▁Gast ine au , ▁an ▁English ▁civil ▁engineer ▁and ▁survey or . ▁ ▁Character istics ▁The ▁channel ▁is ▁navig able ▁by ▁large ▁ships , ▁only ▁from ▁the ▁sout heast , ▁as ▁far ▁as ▁the ▁Douglas ▁Bridge , ▁approximately ▁. ▁Between ▁the ▁bridge ▁and ▁June au ▁International ▁Airport , ▁approximately ▁, ▁it ▁is ▁navig able ▁only ▁by ▁smaller ▁craft ▁and ▁only ▁at ▁high ▁t ide . ▁ ▁The ▁channel ▁is ▁becoming ▁increasing ly ▁un n avig able ▁due ▁to ▁shall ow ▁water ▁depth s . ▁ ▁The ▁two ▁principal ▁causes ▁for ▁this ▁are : ▁ ▁Is ost atic ▁re bound ▁following ▁the ▁retre at ▁of ▁gla cial ▁ice ▁sheets ▁ ▁Sed iment ation ▁and ▁inf illing ▁of ▁the ▁Gast ine au ▁Channel ▁by ▁sil ty ▁sed iment ▁produced ▁by ▁the ▁M enden hall ▁Gla cier ▁and ▁M enden hall ▁River . ▁If ▁current