“Dams played a decisive role in containing the floods,” says Mokhtar Bzioui

    Strong wind gusts, torrential rains, and sudden floods: Morocco has recently experienced severe weather conditions that disrupted daily life across many regions of the Kingdom. Are these exceptional climatic events, or do they signal deeper structural climate transformations? These phenomena raise pressing questions about their intensity, frequency, and underlying causes.

    To better understand the mechanisms behind these disturbances, Walaw spoke with a leading specialist in the field, Mr. Mokhtar Bzioui, President of the Scientific Committee of the Mediterranean Water Institute. Mr. Bzioui has also served as Governor, Treasurer, and Advisor to the President of the World Water Council; Advisor to AMCOW; Advisor to the IAEA for nuclear applications in water resources management; and President of the Scientific Committee of the National Center for Scientific and Technical Studies in Nuclear Energy.

1. How do you analyze the recent heavy rains that affected northern Morocco and the Gharb region, particularly Ksar El Kébir?

    The heavy rainfall that affected these regions resulted from two exceptional meteorological systems caused by the convergence of two air masses over the Atlantic Ocean, off the coasts of Morocco, Spain, and Portugal. One air mass was cold and came from the north. The other was warm, highly humid, and came from the south.

    The interaction of these two air flows produced the weather systems known as Leonardo and Marta. They moved successively eastward, two days apart, generating intense rainfall. In some areas, the amount was equivalent to two to three months of precipitation within just 24 hours.

    These rains were far too intense for runoff to be absorbed or drained by river systems without causing overflow. This occurred despite the crucial role of dams, which significantly contributed to reducing flooding caused by this heavy rainfall.

2. Can you explain this unusual phenomenon to Walaw readers?

    To understand these exceptional climatic events, it is useful to follow rainwater from the moment it falls on the ground until it returns to the sea. This analysis is best conducted at the scale of a watershed. A watershed is bounded by ridgelines, which are its highest points, and slopes downward toward the sea, which is its lowest point. This description applies to the basins concerned here.

    Rainwater partly infiltrates the soil and partly evaporates, while the remainder flows downhill due to gravity. In the Loukkos and Sebou basins, the adverse weather persisted over time, leading to soil saturation and therefore reducing infiltration. In addition, low temperatures reduced evaporation. As a result, nearly all precipitation turned into surface runoff, which is a major aggravating factor in flood management.

    Under these conditions, the successive systems Leonardo and Marta generated exceptionally large floods that required mitigation through preemptive water releases in order to reduce downstream impacts. The case of the Makhazine Dam is particularly significant. Within just a few days, the volume of floodwater reaching the dam represented twice its normal storage capacity. Without anticipatory releases, downstream flooding would have been far more catastrophic.

3. What role do dams play in reducing the impact of such extreme weather events?

    Dams are designed with designated flood-control storage volumes. This is empty capacity deliberately maintained within reservoirs in order to absorb excess water during heavy rainfall.

    However, when these flood-control reserves become filled, their flood mitigation capacity decreases. In the Loukkos basin, this reached 100 percent in nearly all reservoirs. In the Sebou basin, it ranged between 85 percent and 100 percent.

    If these volumes begin to fill, even without official flood warnings, dam managers must immediately release water to restore storage capacity. If the reserves are fully saturated, spillway systems are activated to manage excess flow. When severe weather is forecast, preventive releases are carried out as soon as alerts are issued, generally several days before the flood peak reaches the dam.

    These preemptive releases are conducted through bottom outlets and through turbine operations in dams equipped for hydroelectric power generation. This includes the Makhazine and Al Wahda dams.

    In conclusion, dams played a decisive role in containing the floods.

4. What is the current state of dams in Morocco, and how secure are they?

    Morocco’s dams are continuously monitored through embedded instruments that track settlement, displacement, drainage, and structural performance. During the recent storms, hourly readings were taken at the Makhazine and Al Wahda dams.

    To date, the dams have behaved in full accordance with their design specifications.

    It is important to note that design floods for dams are calculated based on return periods of 1,000 years for concrete dams and 10,000 years for earthfill dams. This applies to the Makhazine and Al Wahda dams. For example, the design flood for Makhazine Dam is set at 3,730 cubic meters per second, while the flood observed during the recent storms remained significantly below that threshold.

5. What lessons should be drawn, and what measures are needed for the future?

    Morocco’s management of the recent severe weather has received international recognition. Major global media highlighted the effectiveness of proactive intervention by Moroccan authorities, noting that without such measures, the toll of the February 2026 floods would have been far heavier. They also praised the professionalism of evacuation operations, described as one of the largest civilian logistical efforts in the history of the region and the continent. The accuracy of forecasts issued by the Moroccan General Directorate of Meteorology and the effectiveness of preventive dam releases were equally praised.

    The recent storms are part of broader climate change patterns observed globally, and they require urgent adaptation measures. Three priorities must guide future action. These are deepening scientific knowledge, integrating adaptation methodologies into planning frameworks, and strengthening monitoring and early warning systems.

    It is equally essential to promote a culture of risk at national, regional, and local levels among all stakeholders. This includes the State, elected officials, experts, NGOs, businesses, banks, and insurance companies. Risk awareness must become an integral component of environmental and sustainable development education. It should be incorporated into school curricula, continuing education programs, and non-formal learning.

    Climate change must also occupy a central place in public communication. The media should be provided with reliable indicators and analytical tools that help inform public opinion about climate-related public policies.