As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON DESCENT AT 19000 FEET HEARD A LOUD BANG. *S/D* AFTER INSPECTION A DENT WAS FOUND ON THE NR 1 RT SLAT DUE TO THE BUILD UP OF ICE ON THE POTABLE WATER SYSTEM DRAIN PORT. REPLACED DRAIN VALVE AND TESTED SYSTEM FOR LEAKS. CONFIRMED CONFIGURATION AND PERFORMED OPERATIONAL CHECK.