City of Ames officials say work is near completion on the largest-ever public construction project. Water and Pollution Control Director John Dunn says preliminary testing is being done on a new $51 million water treatment plant. He says construction of the new plant was driven by an aging treatment facility and a consideration of expanding the old facility. Dunn says it's the city's goal to make a transition from the old treatment plant to the new such that the public won't notice. He says they'll host a ribbon cutting and tours of the new facility later this summer.