Police in Lata, Temotu Province are monitoring the Tinakula volcano and the situation in the province with reports the volcano has contaminated water supplies on some nearby islands.
Reports from the Reef Islands have suggested that people only have a few days worth of fresh water and coconuts to survive on as heavy rain over the past few days has washed toxic ash into waterways and storage tanks.
Authorities have said fresh drinking water was on the way and should arrive today (Wednesday).
Temotu provincial police commander Temotu Province Frank Menesa said police rescued three people over the weekend who had gone to the uninhabited Tinakula island to check on their gardens and pigs.
Mr Menesa said another team of police and agriculture officers visited the island on Monday to monitor the volcano and check on the thirty residents of the nearby Niupani island.
Authorities in Lata continue to monitor the situation and have advised people in Santa Cruz and the Reef Islands to be careful as drinking water in the area has been affected by ash from the volcano.
A no-fly zone meant there had not been an aerial assessment of the eruption.