Many elderly people and children in the Marshall Islands north are suffering from severe diarrhoea, fever, hepatitis and other water borne illnesses as a result of a severe drought.
The government's National Water Advisor, Tom Vance, says he visited Ailuk atoll, which is now struggling with social problems as people on one side of the island have been forced to move because of the lack of fresh water.
He says one island he visited had communities struggling with health issues after drinking water from wells became brackish and undrinkable.
He says the government is grateful for overseas help, including a team that arrived this week from the New Zealand Red Cross.
"We assessed the condition of the wells and also the health of the people. On Mejit they had more diarrhoea amongst children and the elderly and they seemed to be having more health affects so that's where we also really appreciate the New Zealand Red Cross for coming up."
Tom Vance says trees and plants on the islands have also been destroyed by the lack of rain, affecting people's food sources.