(1) In any county that has a population of one hundred seventy-five thousand or more and has an interstate highway within its borders, except for any county having a population of more than one million or a county that has a population more than four hundred thousand and is adjacent to a county with a population of more than one million, transit agencies may elect to establish high capacity transportation service. Such agencies shall form a regional policy committee with proportional representation based upon population distribution within the designated service area and a representative of the department of transportation, or such agencies may use the designated metropolitan planning organization as the regional policy committee.
Transit agencies participating in joint regional policy committees shall seek voter approval within their own service boundaries of a high capacity transportation system plan and financing plan. For transit agencies in counties adjoining state or international boundaries where the high capacity transportation system plan and financing plan propose a bistate or international high capacity transportation system, such voter approval shall be required from only those voters residing within the service area in the state of Washington.
(2) Transit agencies in counties adjoining state or international boundaries are authorized to participate in the regional high capacity transportation programs of an adjoining state or Canadian province.