Residents in a block of flats have claimed to be living without running water for hours on end.
Occupiers at Caerau Court in Caerau, Cardiff, have resorted to showering in the early hours, storing water in containers to wash and cook and buying bottled water.
Some residents said the long-running issue had been going on for 20 years, but has worsened in recent years.
Wales & West Housing, which manages the flats, blamed the issue on a reduction in water pressure in the area which it aims to resolve with a water storage and pump system.
Welsh Water said the pressure in its water network was "well above the required operating standard".
"You won't get a drop through the tap for 10 or 12 hours through the day," said resident Richard Tobin, 75, speaking about the weekends with more residents at home compared with the rest of the week.
"When it does come on, the pressure is so low that it won't heat the boiler or the shower.
"It has just got to a point where it is ridiculous now."