UPPER TSIHALIS UPPER CHEHALIS - UPPER CHILTS - UPPER CHILTZ : Click for LOWER CHEHALIS or STO:LO   Upper Chehalis Territory: Western Washington State.   Portals .   The Confederated Tribes of the Chehalis Reservation : part of whose membership is Upper Chehalis Oakville, Washington Upper Chehalis Population United States (2010) - 250 S A L I S H TSAMOSAN