Isimba Hydropower Dam at risk

Structural defects and contractor delays now threaten Uganda’s energy future
Kampala, Uganda | JULIUS BUSINGE | The Isimba Hydropower Dam, a flagship project in Uganda’s energy sector, was envisioned as a cornerstone of the country’s long-term development goals. Commissioned in 2019, the 183MW facility was meant to provide affordable and reliable electricity, strengthening the national grid and fostering economic growth.
However, mounting structural issues and the persistent reluctance of the contractor, China International Water and Electric Corporation (CIWEC), to carry out necessary repairs now threaten to undermine this critical investment.
President Yoweri Museveni, the Ministry of Energy and Mineral Development (MEMD), Uganda Electricity Generation Company Limited (UEGCL), and CIWEC are facing mounting pressure to address the worsening state of the dam.
The delays in resolving critical defects have raised concerns among stakeholders that Uganda could suffer a total loss of this multi-million-dollar project, burdening taxpayers with an expensive but non-functional infrastructure.
Multiple sources have confirmed that CIWEC has continuously refused to execute essential repairs without providing concrete reasons. Some speculate that the contractor may be financially constrained, making it difficult to complete the outstanding work before receiving the project’s completion certificate. The primary repairs involve diverting the river to facilitate concrete restoration, reinforcing the spillway, and addressing structural weaknesses that threaten the dam’s integrity.
Key interventions
In a high-stakes meeting held on March 4 at the Isimba Dam site, Members of Parliament, UEGCL, MEMD, the Owner’s Engineer (Artelia & Kkatt Consults), and the Dam’s Steering Committee convened to find a way forward. The meeting resulted in several resolutions:
An urgent stakeholder meeting was scheduled to outline the spillway rehabilitation process and river diversion. The Minister of Energy , Ruth Nankabirwa,was cleared to appoint a mediator to resolve any disputes during the execution of the repair plan.
CIWEC was instructed to deploy a competent Planning Manager on-site to oversee the work. It was agreed that all stakeholders, including the Insurance Regulatory Authority (IRA), would discuss modalities for securing a separate insurance cover for the spillway repairs and maintenance of the dam’s outstanding works. MEMD was tasked with guiding the project’s implementation to ensure compliance with national safety standards. All these measures must be executed before the end of April this year to prevent further damage and safeguard the dam’s future.
Urgent concerns
The crisis at Isimba Dam was brought to Parliament’s attention last month, where CIWEC officials were handed over to the Criminal Investigations Department (CID) for presenting contradictory and unconvincing plans to address defects identified in 2022.
UEGCL Chief Executive Officer, Harrison Mutikanga (an engineer by profession) has warned that the dam’s spillway is rapidly deteriorating. Underwater inspections have revealed significant erosion of the spillway’s baffle blocks, he said, exposing critical reinforcement damage. If these issues are not resolved urgently, more than 2,000 people living downstream could be at risk.
“Our concern is that these deficiencies were discovered in 2022, and we had a clear schedule for the contractor to fix them,” Mutikanga explained. “Our recent inspections show that the concrete forming part of the spillway continues to degrade, and the riverbed is undergoing erosion. If we delay further, backward erosion could extend to the dam’s foundation, potentially leading to catastrophic failure.”
Despite clear evidence of structural concerns, CIWEC officials have continued to resist corrective measures. In response to directives from the Minister of State for Energy, Okaasai Opolot Sidronius, the company insisted on conducting a Physical Model Test (PMT) before commencing any work—a move that officials fear could lead to further delays.
CIWEC’s President, Prod Wanga, has even claimed that the dam is free of defects, contradicting the company’s own December 2024 report, which acknowledged the need for urgent Level-2 repairs to prevent further deterioration.
Members of Parliament have expressed deep frustration over CIWEC’s lack of commitment.
“We were alarmed by the contradictions between the Owner’s Engineer and the contractor. The contractor has failed to demonstrate a clear commitment to resolving these defects,” said Committee Chairperson Herbert Edmund Ariko. “This project is crucial for Uganda’s energy stability, and we cannot afford further delays.”
Minister Okaasai echoed these sentiments at the March 4 meeting: “We cannot continue delaying what must be done. This dam is critical to ensuring a stable electricity supply in the country. The time for discussions is over—we need action and results.”
A flagship project at risk
The Isimba Dam was built for $570 million (Shs2.2 trillion), largely funded through a loan that Ugandan taxpayers must repay. Yet, nearly five years after its commissioning, less than 50% of its generation capacity is being evacuated to the national grid partly due to unresolved structural problems.
Uganda’s long-term development strategy relies heavily on stable and affordable electricity to drive industrialization and economic growth. Isimba Dam was meant to play a crucial role in this vision, helping to achieve national electrification goals and reduce reliance on expensive thermal energy sources. However, the persistent failure to enforce contractor accountability now threatens not only the dam’s lifespan—meant to be at least 100 years—but also the country’s broader development objectives.