Televised ducts under slab floor. Ducts are concrete ducts with metal fitting hat are extremely rusted. There was standing water throughout most the system. There is a sump pit and pump and it appears the drain tile is lower than the heating ducts and plenum. Suggest maybe rodding drain tile to see if that opens it up and reduces the water. If that does not help a possible pit and pump outside to help reduce water level then spin cast mortar and spray line ducts with Duct Armor duct lining material.