CAIRO (Reuters) – Ethiopia has accused Egypt of trying to maintain its grip over the waters of the Nile with a proposal it says would imperil a giant hydropower dam under construction on Ethiopia’s Blue Nile, in a growing diplomatic spat.

The comments highlight the difficulties finding a compromise between the two countries over the Grand Ethiopian Renaissance Dam (GERD). Two rounds of talks over the past month in Egypt and Sudan failed to produce progress.

Egypt relies on the Nile for up to 90% of its fresh water, and fears the dam, which is being built in Ethiopia close to the border with Sudan, will restrict already scarce supplies.

After talks had stalled, Egypt had submitted a proposal on Aug. 1, including conditions over filling the reservoir, that Ethiopia rejected.

In an explanation for its decision, Ethiopia said the Egyptian plan was “one-sided”, flawed, and would ultimately hamper its economic development.

“Egypt’s proposal is an effort to maintain a self-claimed colonial era-based water allocation and veto power on any project in the Nile system,” the Foreign Ministry said in an Oct. 1 note circulated to embassies, a copy of which was seen by Reuters.

The Egyptian Foreign Ministry could not be immediately reached for comment.

The $4 billion dam is designed to be the centerpiece of Ethiopia’s bid to become Africa’s biggest power exporter, generating more than 6,000 megawatts, and is seen by Addis Ababa as a step toward redressing a historic imbalance in the exploitation of the Nile’s waters.

Ethiopia said at the start of the year that the dam should be fully operational by 2022.

FILLING PROCESS

Both sides agreed on a five stage process for filling the reservoir behind the dam. Ethiopia says that while it could fill the reservoir in 2-3 years, it made a concession by proposing a 4-7 year process.

Egypt did not mention a timeframe for filling the dam’s reservoir in a diplomatic note last month that acknowledged Ethiopia’s rejection, but said it was requesting that the initial, two-year stage could be extended in conditions of “severe drought”.

“Meeting this demand is tantamount for Ethiopia to agreeing to make the filling of the GERD subject to Egypt’s approval at any stage,” the Ethiopian note said.

“Ethiopia, therefore, finds this ‘proposal’ a non-starter on technical, economic, and national sovereignty grounds.”

After the first stage of filling, Egypt’s proposal requires a minimum annual release of 40 billion cubic meters of water from the GERD.

Ethiopia said such an amount was unrealistic in years of drought, and that in 1984 the flow had reduced to less than 30 BCM, and that Egypt wanted to “protect itself by putting the burden of coping with extreme drought years entirely on Ethiopia”.

Egypt’s proposal to link water levels in the GERD dam to those at its own High Aswan Dam (HAD), “puts the GERD hostage to the HAD”, the note added.

Ethiopia denied Cairo’s assertion that it had held up talks, pointing instead to what it called Egypt’s “unfortunate smearing effort”.

“Despite the negative diplomatic and media campaign that is coming out of Cairo, Ethiopia was forthcoming to the resumption of tripartite talks,” the note said.