Representatives from 22 countries are meeting in Alice Springs this week to discuss water quality in small communities.

WHO spokesman Professor Jamie Bartram says 50 per cent of the world's population does not have access to safe water.

He says governments, especially in wealthy countries, should help improve that statistic.

"In part because of the huge contribution this can make to poverty, so it's an ethical question as well as a simple economic one," he said.

Professor Bartram says halving the number of people who do not have access to safe water would cost $1.8 billion.

But he says quality water could help save the 1.6 million children who die each year from diarrhoeal disease and would also shave billions of dollars off health budgets worldwide.