The work consisted of a concrete pre-ozonation contractor, including plant inlet flow metering and control. The project included two concrete pretreatment basins, with a common rapid mix system, flocculation equipment and clarification equipment. Filtration improvements included two gravity filters in concrete structures, two concrete washwater recovery tanks and associated pump room, wet well sumps and tank equipment. The existing pre-treatment basin was converted to a building housing ozone generation and off-gas destruction equipment, polymer blending, an engine generator and future sludge dewatering equipment. A chemical storage building included indoor and outdoor chemical storage tanks and outdoor liquid oxygen (LOX) storage on a concrete slab. Overaa retrofitted four existing gravity filters with new under drains and media. Overaa also retrofitted existing wash water reclamation basins with new pumps. An electrical building houses a new electrical service.