Televised ducts under slab floor. Ducts are galvanized and are heavily rusted with gravel and standing water. Work needs to be done on gutters and dwnspouts to control water in ducts. If work on the gutters does not solve water issue then a sump pit and pump is suggested in the backyard. After the water is controlled the ducts should be spin cast mortared then spray lined with Duct Armor duct lining material.