Water isn't yet flowing this year from one of several culverts at the Prairie Creek treatment train site along the south side of Grand Lake. Workers on Wednesday put two pumps in place and will change some wiring before beginning operations this year, according to local lake advocate Milt Miller. When the pumps are up and running again, a portion of the water from nearby Prairie Creek will be diverted and filtered through retention ponds, wetland cells and natural wetlands before entering the lake. Miller said he expects the process to be even more effective this year due to the growth of new vegetation. It is estimated that up to 200,000 tons of sediment enter Grand Lake each year. The Army Corps of Engineers and Ohio Environmental Protection Agency cite sedimentation, phosphorus and nitrogen as primary contributors to the decline in lake water quality.