KOSTI, Sudan (Reuters) - Four months after Paula Lodo left her Khartoum slum to head back to South Sudan, she finds herself in yet another makeshift home south of the Sudanese capital.
"I am stuck on the way home for four months, can you believe this?" Lodo said, sitting with her six daughters in a dusty tent camp near this northern White Nile city.
Like tens of thousands of other southerners, Lodo packed up and left Khartoum in anticipation of the coming split between Sudan and South Sudan, catching a truck to Kosti to continue southwards by barge.
But the barge to bring her home never showed up and she is now stranded with 17,000 others in a camp originally built for 1,200. Heavy rain has created a large pool in the middle of the facility, filled with garbage and attracting scores of flies.
Lodo has put up a tent made from the same plastic sheets, blankets and wood branches used to build her home in Khartoum where she lived for 32 years after fleeing the civil war.
"We were promised boats to continue but we are still here. I don't know why. It's very bad," Lodo said, seeking relief from the scorching sun under the shade of a large tree.
The United Nations has estimated that more than 342,000 people have made the move southward since October, a few months before the independence referendum in January set July 9 as the date when South Sudan would become independent.
Khartoum has given the more than one million southerners who still live in the predominantly Muslim north until spring to either leave or get residency and work permits -- a complicated process.
Mostly Christians or people who follow traditional beliefs, and facing legal or employment uncertainties, many southerners can't wait to leave.
But many are also somewhere stuck on the way home -- at railway stations, major roads or in Nile ports like Kosti.
The delays are partly to do with a lack of coordination among the two governments and partly to do with the financial difficulties of South Sudan, which cannot provide sufficient transport. Non-governmental organizations are trying to help.
"We want to go to our home village. We don't know why we can't go on," said Samira Otsmu, who has been waiting in the Kosti camp since July for a barge to bring her family and few belongings to the southern capital of Juba.
Experts mostly blame the shortage of barges on the Juba government which started a program to bring southerners home but is running out of funds. More barges are being rented with the help of United Nations and NGOs but many more is needed.
Much poorer than the north, South Sudan is facing a myriad of challenges from setting up state institutions and building infrastructure to ending widespread tribal and rebel violence.
"The situation is improving now but we need more efforts," said Sultan Ali Kanji, an official in South Sudan's relief commission who is trying to coordinate travel.
He said the key problem apart from finding funds was a lack of coordination between north and south on how to organize the return of southerners and accommodate them in transit camps.
"What we want from the NGOs and the Republic of South Sudan and this government is to agree on one thing. They should bring the returnees to their home villages," he said, standing in front of a rusty barge being loaded with luggage.
Many thousands have gone home by trains or made the arduous journey by bus or lorry. But those like Lodo coming from eastern regions often have no choice but to go by barge as their villages lie by the Nile and are not serviced by good roads.
More than 18,000 southerners are stuck in Renk, the first southern port on the White Nile after Kosti, the United Nations said on Monday.
One big obstacle is that many are bringing with them their entire household belongings and even, as in Lodo's case, the branches and corrugated iron they used to build their slum homes.
"Twenty-six river barges now left of which 15 were loaded only with luggage and nine with passengers," said Mohammed Abdul Raziq, a senior northern relief official working in the camp.
"If it hadn't been for the luggage it would have been possible to transport all the returnees," he said, speaking as a truck from Kosti town prepared to distribute water in the camp.
But for poor southerners like 34-year-old Charles Nelson, leaving behind furniture is out of question.
"It's impossible, nobody can leave his luggage behind," he said, sitting with his family in front of a tent they live in.
With nothing to do, a group of young men nearby play dominoes at a plastic table, their main activity for months.
"It's the unemployment that makes us play dominoes," said Yaqoub Agolav, who also came from Khartoum. "If we go to the south we will find work, but we have been here for three months unable to go to the south and we don't know why."
Editing by Sonya Hepinstall