ADVANCE FOR USE SATURDAY, SEPT. 26, 2015 AND THEREAFTER - In this Thursday, Sept. 17, 2015, photo, a worker sweeps gravel on the construction site of the new water treatment plant in Ames, Iowa. The largest federal aid program for improving the nation?’s crumbling drinking water infrastructure has struggled to spend money in a timely fashion despite demand that far outpaces the amount available, a review by The Associated Press shows. The program does the most for small and mid-sized systems that need capital for projects, such as the $76 million loan for the plant being built in Ames. (AP Photo/Charlie Neibergall) ORG XMIT: NY321