Welsh Water has said that it hopes to restore water supply to about 4,500 affected homes by the end of Tuesday.
In Ceredigion homes were left without little or no water. A period of cold weather appears to have taken its toll on supply pipes.
Schools across the county have been forced to close. Welsh Water have apologised and say their efforts have been hampered by heavy rain.
“Due to the incredible efforts of the curator and museum volunteers, most of the priceless regimental artefacts were recovered, but significant damage was caused,” a spokesman said.
People have been forced to get water from distribution centres
The following schools were closed on Monday due to the water shortage:
Ysgol Ciliau Parc
Ysgol Gynradd Aberteifi
Ysgol Gyfun Aberaeron
Ysgol Bro Teifi
Canolfan Aeron, Ceredigion Pupil Referral Unit (PRU)
Areas of Carmarthenshire were also left without water. Cynwyl Elfed has been without water for almost two days. There have also been intermittent power cuts.