The Blue Nile is a renegade river, according to Sudanese farmer Osman Idris, its unpredictable flooding swallows crops and houses as it crashes through Sudan from Ethiopia on its way to Egypt.
"Tonight, the level of water will be low," said Idris, a resident of Juref Gharb, a small village on the bank of the Blue Nile outside Khartoum.
"Tomorrow, it will swallow all the houses... It's a renegade river, it rises so fast," said the 60-year-old, dressed in a traditional Sudanese robe, AFP reported.
For Idris, Ethiopia's construction of a controversial dam on the Blue Nile is a dream come true, as it promises to regulate the floods that inundate Sudan every rainy season.
This year alone, flash flooding has killed more than 60 and injured dozens in Sudan.
The Blue Nile joins the White Nile in Khartoum and supplies the overwhelming majority of the Nile's water, which runs through Egypt to the Mediterranean Sea.
Construction of the Grand Ethiopian Renaissance Dam began in 2012, but since then Egypt has sounded the alarm that the project would severely reduce its water supplies.
Egypt depends on the Nile for about 90 percent of its irrigation and drinking water, and says it has "historic rights" to the river guaranteed by treaties from 1929 and 1959.
It sees the project as an existential threat, fearing Ethiopia's rapid construction of the dam might lead to water and food scarcity for millions of Egyptians.
- More cash crops -
After several rounds of talks failed to resolve the issue, a new dialogue between Egypt, Ethiopia and Sudan was mediated by the United States in Washington earlier this month.
The three delegations agreed to resolve the dispute by January 15, with ministerial-level talks being held this week in Addis Ababa.
Ethiopia insists the $4 billion hydro-electric barrage is essential for its economic growth given that most of its population still lives without electricity.
And in Sudan, farmers hope the dam will provide predictable flow.
Over the years, farmers like Idris who own farms along the Nile have been forced to change their crops due to flood devastation and tonnes of deposited silt.
Brickmakers fire blocks of mud in riverside kilns, producing smoke harmful to crops.
"I had to shift from cultivating fruits and vegetables to animal feed," Idris told AFP.
Being reliant on flooding for irrigation means only one harvest per year and limits the kind of crops that can be grown.
If the river's flow were regulated, more intensive agriculture could be practised, Idris said.
"We can plant crops through the year. It will be better for the environment and for marketing our products, which means more income for us," Idris said.
Ekram Dagash, a professor at Khartoum's Al-Zaiem Al-Azhari University, agreed that Sudan stands to gain from the dam, which will maintain water levels and block unwanted silt.
"Ethiopia is building the dam for one reason only, to produce electricity and export it, not only to neighbouring countries but to the whole African continent," she told AFP.
- Worried brickmakers -
But one group of Sudanese are concerned about the dam: brickmakers, who depend on the silt for their livelihood.
Dozens of small kilns line the river, providing an income for hundreds of brickmakers like Yakoub Noreen.
"If the dam is built, this won't arrive," the 40-year-old said of the silt he was standing in, as he pressed wet clay into a mould.
Nearby, workers stacked bricks into a kiln belching thick smoke. Later they will be sold for 1,500 Sudanese pounds ($32) per 1,000 bricks, Noreen said.
Professor Dagash said workers can be compensated and provided alternative livelihoods if brickworks close, adding that benefits from the dam outweighed such losses.
Vast areas of land would open up for agriculture as well as industrial projects, she said.
"The dam will provide Sudan with low cost electricity... and low cost electricity means more growth," she said.
