As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED. EMERGENCY DECLARED. NRT-DFW FLIGHT RETURNED TO NRT ACCOUNT NO POTABLE WATER IN THE MID GALLEY AND MID LAVATORIES. OVERWEIGHT LANDING UNEVENTFUL. FOUND WATER LEAK FROM FORWARD CARGO WATER DRAIN LINE. REPLACED RETAINER AND REINSTALLED CAP. LEAK CHECKED NORMAL IAW AMM 38-10-00.