Government in Mattawa, WA Mattawa Town Hall521 Government RdMattawa, WA, 993495099324037City HallGovernment City Village TownshipMarriage LicenseUnion Gap City HallUnion Gap Water Dept Mattawa Town Office710 N Portage AveMattawa, WA, 993495099329304Government City Village TownshipMarriage License Show MoreSee AlsoCity, Village & Township GovernmentCommunity Services