Samoa's Electric Power Corporation has started to ration power supply to most parts of Upolu island.
Power was switched off from 10 o'clock yesterday morning until 6 in the evening, and will continue to the end of the week.
However power users have criticised the Corporation for not warning them of their decision.
While there has been no immediate explanation from the corporation, a source has revealed that the hydro power stations at Ta'elefaga and Lalomauga were shut down because of low water supply from local dams.
The same source has also said that two of the three main diesel generators at Tanugamanono were shut because of technical faults.