Televised ducts under slab floor. Ducts are PVC with metal connections and fittings that are rusting. Downspouts in back of house are run out but are not pitched so water is frozen in downspouts not allowing water to flow properly. Suggest reconfiguring downspouts so there is more pitch so water will not freeze in them. This will reduce the amount of water accumulating next to the house which causes water to enter into the ducts. Once the water issue is resolved the ducts should be spray lined with Duct Armor duct lining material.