A short but severe hailstorm in Katoomba on Sunday night created waterfalls inside Blue Mountains Hospital as the ageing roof struggled to cope.
Staff rushed to put buckets underneath some of the worst leaks as whole corridors were awash.
But no patients were affected.
The hospital’s general manager, Andrea Williams, said it appeared the hail had blocked the gutters, letting the rain in. She stressed damage was caused in corridors and in common areas, not wards.
“There was no rain in the patients’ bedrooms. No patients were moved.”
John Hughes, Blue Mountains Local Controller for the SES, said Katoomba had more than 20 millimetres of rain in just 30 minutes.
“It seems that we have had an extended summer storm season,” he said. “The daily storm events are known to hit us in January and February, but never this bad in March”.
The Premier, Barry O’Farrell, and Blue Mountains MP Roza Sage, visited the hospital on Monday morning to see the damage first-hand.
They saw several missing ceiling panels which had come down in the deluge and in the dental ward there were still piles of ice that had not yet melted more than 12 hours after the storm.
Mr O’Farrell praised the work of emergency workers, who had responded with water-vacuum equipment to help clean up.
Staff in the maternity ward joked about “waters breaking” as they continued the mop-up in their area.
The hail also caused havoc at the Sports and Aquatic Centre which will remain closed until further notice while the damage to collapsed ceilings is assessed.
