Operations planned for Monday morning at hospitals in Manchester have been cancelled due to a mains leak affecting the water supply.
Cancer and any urgent operations will still go ahead, the Manchester University NHS Foundation Trust said.
The hospitals affected are the Royal Infirmary, the Royal Eye Hospital, Saint Mary’s Hospital and Royal Manchester Children’s Hospital.
The water supply was restored earlier and operations will take place later.
Anyone with an outpatient appointment should still attend hospital as planned, the trust said.
It added that operations scheduled for Monday afternoon would take place, and cancelled operations would be rescheduled as soon as possible.
One patient tweeted about the affects on the patients the water outage had on Sunday evening, calling it a “shocking situation”.
Prof Cheryl Lenney, director of infection prevention and control for the trust, said: “Our sterile services require a significant amount of water to sterilise instruments, so it’s really important that we knew that the water supply to that department was functioning properly.
“We’ve got the all-clear this morning so our operations will go ahead this afternoon.”
She said on Sunday water tanks “had reached critical levels” and the hospital implemented water-saving actions including using hand washing gel and wipes and asking patients not to flush the toilet for a short time.
Writing on Facebook, Anne Marie O’Toole said: “I was at children’s a & e this evening, the staff were professional, courteous, apologetic and very kind.
“They were extremely busy and stretched during this major incident, but standards never slipped, heartfelt thank you to all I came in contact with.”
United Utilities said it worked urgently through the night to repair a leak on Oxford Road, before a further “smaller scale” leak was found on Monday morning at Moss Lane East.
“We are currently in the process of repairing the main,” a spokesperson said.
He added that none of the hospitals were without water during the repairs.