As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMBOUT, FA STATED WATER PRESSURE IN LAVS AND WATER DISPENSED WITH COFFEE MAKERS LOW PRESSURE, THROUGHOUT AIRCRAFT. ACFT GROUNDED. AIR TURNBACK. OPENED THE WATER SERVICE PANEL, CYCLED WATER DRAIN VALVE OPEN THEN CLOSED. WATER PRESSURE & FLOW NORMAL FROM ALL LAVS, TOILETS AND SINKS.