Wash. Rev. Code § 47.17.285
A state highway to be known as state route number 150 is established as follows: Beginning at Manson, thence southeasterly to the north of Lake Chelan to a junction with state route number 97-alternate at Chelan. Also beginning at a junction with state route number 97-alternate at Chelan southerly to a junction with state route number 97 in the vicinity of Chelan Station.
[ 1987 c 199 s 13; 1970 ex.s. c 51 s 58.]