Oxfam said on Friday that at least 16 refugees have died of hepatitis E in the past few weeks, and aid workers fear the figure could rise in the coming months.
Conditions in Yusuf Batil camp are especially dire, the International Committee of the Red Cross (ICRC) said on Thursday.
"Owing to the lack of clean water, people are drinking contaminated surface water," Melker Mabeck, head of the ICRC delegation in South Sudan, said in a statement. "Children are especially vulnerable to death from water-borne diseases such as diarrhoea."
Oxfam said new, safe locations should be identified urgently for thousands of the refugees, to ease the burden on Maban's four overcrowded camps. It also called for more funding for humanitarian operations in the area.
During a year of conflict in Sudan's Blue Nile state, 109,000 people have fled across the border to the four camps in Maban in the northeast of South Sudan, which are threatened with recurrent flooding from heavy rains, Oxfam said. After the rainy season ends in November, another 60,000 people could arrive once movement becomes possible again, the charity warned.
"These refugees have struggled to survive a year of hell. The Maban camps alone are not an answer to the crisis – there is simply not enough groundwater to sustain so many people, and now heavy rains have left people wading through mud to get basic services," said Pauline Ballaman, head of Oxfam's emergency response in Maban.
The ICRC is installing pipes, tanks, tapstands and pumps to provide enough water for half the population at Yusuf Batil camp, and distributing jerrycans and buckets so people can collect and store water, it said. And in nearby Jamam camp, which also suffers from very limited access to water, the agency is close to completing a 15 km distribution pipeline to serve the 30,000 refugees there.
Oxfam is providing clean water and sanitation, and running public health campaigns for around 28,500 people in the Jamam and Gendrassa camps, while also running a long-term programme to provide water to local villages and host communities.
'EXPENSIVE' AID RESPONSE
Aid agencies have so far managed to prevent a major crisis during the rainy season, Ballaman said. But if the refugees stay where they are, hundreds of millions of dollars will be needed to keep assisting them with food and water, she added.
During the rainy season, aid can only be brought into Maban - one of South Sudan's most remote and least-developed areas - by air or boat. Combined with the high cost of fuel and a scarcity of supplies due to the country's conflict-driven economic crisis, the humanitarian response is one of the world's most expensive, Oxfam said. Its response alone needs at least $5 million for the next six months.
"It's likely to be several years before refugees feel safe to return home, and people need to be given the choice of moving to more appropriate camps outside Maban,” Ballaman said.
Growing competition over scarce water and trees cut down for construction at refugee sites is likely to exacerbate tensions between the newcomers and impoverished local communities, the agency warned.
Sudan's state media reported this week that President Omar Hassan al-Bashir is due to hold a summit with his counterpart from South Sudan, Salva Kiir, in Ethiopia on Sunday to wrap up two weeks of talks to end hostilities.
According to Reuters, diplomats said there has been progress after the two weeks of talks but no breakthrough yet on setting up a demilitarized buffer zone at the unmarked border, much of which is disputed.
Oxfam called for an immediate end to fighting in the Sudanese border states of Blue Nile and South Kordofan, and for aid to be urgently allowed into the region, where tens of thousands more people are estimated to be displaced or severely affected by the conflict.