RCW 35.61.110

Every metropolitan park district may contract indebtedness not exceeding in amount, together with existing voter-approved indebtedness and nonvoter-approved indebtedness, equal to two and one-half percent of the value of the taxable property in said district, as the term "value of the taxable property" is defined in RCW 39.36.015, whenever three-fifths of the voters voting at an election held in the metropolitan park district assent thereto; the election may be either a special or a general election, and the park commissioners of the metropolitan park district may cause the question of incurring such indebtedness, and issuing negotiable bonds of such metropolitan park district, to be submitted to the qualified voters of the district at any time.