Many have been forced to set up shelter on the edges of the nearby Dagahaley camp.
It is one of three refugee camps in Dadaab in northern Kenya, where aid agencies are struggling to provide water and toilet facilities for its soaring population.
Nearby, a new camp that can house 40,000 people and boasts some of the best facilities in the area, including six schools, stands empty.
A group of aid agencies finished building camp Ifo II, last year but Kenya’s government won’t open it.
Political leaders are worried that opening such a well-equipped camp will only encourage more people to cross the border into the East African country. More people flooding into the country could create a security threat, they say.
Kenya’s Prime Minister Raila Odinga, promised 11 days ago that Ifo II would open within 10 days. But on Sunday, the gates were still locked.
"People are already here so they need to be served properly,” said Magdalen Nandawula, from Oxfam, which is one of the aid organizations that helped set up Ifo II. “Outside the main camps there's no infrastructure, no latrines or water. At Ifo II we have water from four boreholes, it's all finished. The crazy thing is that water from these boreholes is now being trucked to supply tanks elsewhere," she told the Independent newspaper.
Fatima Aden Mohammed, 30, is one of estimated 12 million people on the brink of starvation. She and her family walked for 25 days from Somalia's Juba valley to get to Dagahaley camp. Her youngest daughter, Habiba died of malaria and malnutrition before they had crossed the border.
They’re most likely to end up staying on the cramped edges of Dagahaley camp, said aid worker Shueb Mohamed Hassan. "Most people who leave this reception centre end up there. Ifo II is very nice but it is not open. They have nowhere else to go."
To avoid landmines, armed rebels and to get to hard to reach, parts, The World Food Programme is planning air-drops.
The World Bank today pledged more than £300million in emergency aid to help the starving. It is important to “act fast to reduce human suffering,” said World Bank President Robert Zoellick. The cash will help pay for both short- and long-term aid in East Africa including Ethiopia, Djibouti, Kenya and famine-struck Somalia.