A recent view of downtown Waterville. Photo by Charley DiAdamo.WATERVILLE — Facing rising costs and reduced state revenue, the city recently wrapped up the last of four budget workshops as officials work to shape next year’s spending plan. The sessions, along with a public hearing on the budget proposal set for Thursday, May 7, are meant to get Waterville residents more involved in the budget process. City Manager Nick Cloutier is urging taxpaye…