Science Supports Cooperation, Not Compensation Claims

By: Abebe Sine Gebregiorgis, PhD, PE, CFM

On January 19, 2026, Egypt Independent published an article titled “Grand Ethiopian Renaissance Dam Must Pay Compensation to Egypt and Sudan.” While the headline is striking, the article itself fails to present any verifiable scientific or hydrological evidence to substantiate such a claim.

On the contrary, a more compelling argument can be made that Ethiopia has long been denied the right to utilize its own natural resources, constrained for decades by colonial-era treaty arrangements to which it was never a party. These outdated frameworks lack legitimacy and cannot credibly govern equitable water use in the 21st century, when principles of fairness, sustainability, and shared benefit define modern transboundary water governance.

If downstream countries choose to frame the Nile debate in terms of payments, it is equally conceivable - under contemporary resource-management principles - that Ethiopia could, in the future, consider charging for regulated releases exceeding agreed environmental thresholds, particularly during drought mitigation or flood-control operations. Such discussions, however, fall outside the scope of this article and will be addressed separately with supporting technical analysis.

The purpose of this response is more immediate and practical: to examine and rebut the claim that GERD must pay compensation, using basic hydrological principles, observed flow data, satellite observations, and internationally recognized water-law norms.

The Claim of “Unilateral Action”

The assertion that the Grand Ethiopian Renaissance Dam (GERD) was constructed through “unilateral action” is not supported by historical or technical evidence. Since 2011, Ethiopia has undertaken sustained diplomatic and technical engagement, including:

• Conducting multiple rounds of tripartite negotiations with Egypt and Sudan;

• Signing the 2015 Declaration of Principles (DoP), which explicitly recognizes Ethiopia’s right to utilize the Blue Nile while committing to cooperation, data exchange, and the principle of equitable and reasonable utilization;

• Allowing international expert panels to review dam safety, hydrological modeling, and reservoir-filling scenarios.

International water law does not require prior consent from downstream states for upstream development. It requires notification, consultation, and the avoidance of significant harm -obligations Ethiopia has demonstrably pursued in good faith.

The Alleged Reduction of 38 Billion Cubic Meters

The claim that GERD has reduced Egypt’s annual share by 38 billion cubic meters (BCM) is hydrologically untenable. GERD is fundamentally a hydropower project, not a consumptive water-use scheme. It does not divert water for irrigation, export, or permanent storage. All inflows continue downstream after turbine passage, subject only to temporary regulation for energy generation.

The only period of reduced downstream flow occurred during the initial reservoir-filling phase, which:

• Was conducted incrementally over multiple years;

• Coincided largely with above-average Blue Nile inflows, mitigating downstream impacts;

• Resulted in no statistically detectable long-term reduction in Nile flows at Aswan.

No peer-reviewed hydrological study or observed discharge record supports a permanent loss approaching 38 BCM. Such a reduction would require massive consumptive abstraction or evaporation far beyond physical limits—neither of which applies to GERD.

Lake Nasser Water Surface Elevation Variability: Observational Evidence

Independent satellite altimetry observations of Lake Nasser water surface elevation (WSE) provide direct empirical evidence that downstream water levels during the GERD filling period (2020–2024) remained within natural historical variability.

Long-term altimetry records show that Lake Nasser has experienced pronounced seasonal and multi-year fluctuations for decades, well before the construction and filling of GERD. Critically, water-level variations observed during the GERD filling period are neither unprecedented nor anomalous when compared to earlier periods driven by natural hydrological variability, basin-wide rainfall patterns, and reservoir operations.

During the GERD filling years, Lake Nasser did not exhibit abrupt, sustained, or irreversible declines that would indicate permanent water loss. A reduction on the order of 38 BCM would have produced a clear and persistent drop in reservoir elevation far outside historical norms—an effect that is absent in the observational record. These satellite-based observations confirm that GERD’s role has been one of temporary flow regulation, not permanent abstraction, and they directly contradict claims of measurable downstream damage requiring compensation.

Figure 1. Lake Nasser satellite altimetry–derived water surface elevation (WSE) from the early 2000s to 2025. The shaded region denotes the GERD reservoir filling period (2020–2024). Observed fluctuations during this period remain within historical variability, with no evidence of unprecedented or permanent decline attributable to GERD operations.

Reservoir Size, Storage, and Evaporation

GERD’s reservoir capacity of 74 BCM represents storage, not loss. Annual evaporation losses from GERD are estimated at 1.5-2 BCM, significantly lower than Lake Nasser’s approximately 10-12 BCM, due to GERD’s higher elevation and cooler climate. Over time, this difference reduces total basin-wide evaporation, benefiting all downstream users. The reservoir was filled gradually in five stages by 2024, with releases carefully adjusted to avoid critical downstream shortages. From a basin-wide perspective, GERD improves hydrological efficiency rather than diminishing available water.

Rising Water Demand and Scarcity in Egypt

Egypt’s water stress is understandable and deserving of serious attention. However, attributing it to GERD is scientifically incorrect. Primary drivers include:

• Rapid population growth;

• Expansion of water-intensive agriculture in arid regions;

• Inefficient irrigation practices;

• Climate-change impacts and internal system losses.

GERD does not reduce Egypt’s allocation under the 1959 agreement. Instead, it exposes the structural mismatch between fixed colonial-era allocations and modern demand growth. Egypt’s increasing reliance on water reuse, desalination, and efficiency improvements—acknowledged by its own authorities—confirms that scarcity is largely endogenous, not caused by upstream storage.

Claims of Flooding in Sudan

Assertions that GERD caused uncontrolled flooding in Sudan lack hydrological substantiation. Flooding along the Blue Nile is seasonal and historically recurrent, predating GERD by centuries. Available discharge data indicate that GERD operations have reduced flood peaks, stabilizing flows near the Roseires and Sennar dams and enhancing operational safety.

Any short-term operational misalignment does not constitute “damage”; rather, it underscores the importance of real-time coordination, which Ethiopia has repeatedly proposed. Sudanese technical institutions have previously recognized GERD’s benefits in flood control, sediment reduction, improved irrigation reliability, and enhanced downstream dam safety.

Compensation Claims under International Law

International water law does not recognize compensation claims without:

1. Proven significant harm;

2. A clear causal link between the project and the harm;

3. Failure to exercise due diligence.

To date:

• No independent, peer-reviewed assessment demonstrates measurable, attributable harm caused by GERD;

• Downstream flow volumes remain within historical variability as presented above;

• Ethiopia has complied with the “no significant harm” principle while exercising its legitimate right to development.

Accordingly, demands for compensation lack both legal foundation and scientific credibility.

Conclusion

The Grand Ethiopian Renaissance Dam has not caused permanent water loss to Egypt or Sudan, nor has it violated international legal norms. Claims of massive reductions, unilateral action, or compensable damage are inconsistent with hydrological data, dam-engineering principles, and observed system behavior.

Rather than a threat, GERD represents a transformative opportunity for:

• Basin-wide flow regulation;

• Reduced evaporation losses;

• Enhanced drought resilience;

• Cooperative Nile Basin management.

A sustainable future for the Nile will not be built on unfounded claims, but on data sharing, coordinated operation, and regional cooperation guided by science and international law.

Cooperation - not compensation claims - is the evidence-based path forward.