The making of Isimba Dam crisis, the ignored red flags
Isimba Hydro Power Plant (HPP) is located 4km downstream of Simba Falls on the River Nile. Photo/COURTESY
What you need to know:
- Last week, the government and the China International Water and Electric Corporation (CIWEC), contractors of the Isimba Hydro Power Dam, agreed to collaborate on fixing critical defects threatening Isimba Dam’s integrity.
- We look back at a cat-and-mouse game that has taken close to four years and only time will tell whether the new agreement will yield results.
“How you do anything is how you do everything,” goes an old saying that carries multiple meanings, including that one’s actions in a particular situation are usually telltale of how one will act in all other situations.
The adage perfectly sums up a lot of things in Uganda. The average construction time for a road project, even those less than 10km, ranges from five years to forever, before it starts crumbling in no time: that is not to mention the absence of proper signage or proper lighting systems. Many high-rise buildings sprouting in and around Kampala are without proper design standards, including flouting the established building code.
Despite repeated warnings about the dangers of the proliferation of fuel stations, many squeezed within human settlements, licences for new others continue to be handed out. Add to the mix, loaded fuel tankers that squeeze within traffic during rush hour.
The occasional landslides on the Mt Elgon range in eastern Uganda that cost lives and property, year-in and out, happen with enough documentary evidence that large swathes of the area are unsuitable for human settlement.
Just like the Kiteezi landfill accident last August, sufficient red flags had been raised as early as 2015 amid non-budget prioritisation by those in charge until disaster struck. This, as plans to establish a modern dumping site in Mukono District that generates waste into either electricity or fertilisers, were thwarted by bureaucracy with an icing of officials seeking kickbacks from investors.
Hydroelectric power dams are designed to run for 100 years. But for the 183megawatts Isimba Dam at the parallels of Kayunga and Kamuli districts, the cacophony of back-to-back inquires, six years after it was commissioned, raises questions about how long it will run while engineering audits point to a deadlier and costlier accident waiting to happen.
During an inspection meeting by the Parliamentary Committee on Environment and Natural Resources last week, MPs were told that a report of the probable impact of the Isimba dam washing away had already been submitted to the Ministry of Disaster Preparedness. The impact would be deadlier, wash away surrounding villages, and be way costlier as there is the 600 megawatts Karuma dam upstream.
Since commissioning of the Shs2.2 trillion dam, a flagship symbol of the Uganda-China bilateral relations, the Engineering, Procurement and Construction (EPC) contractor, China International Water and Electric Corporation (CIWEC) has been locked in a simmering blame game with the project owners, Uganda Electricity Generation Company (UEGCL) and Energy ministry over remedying several defects, some categorised as “high risk” that were identified during the mandatory Defects Liability Period (DLP).
DLP is the period specified in the contract during which a contractor is legally required to return to a construction site to repair any defects. It first expired in 2022 and since then it has been extended episodically to allow CIWE to fix the flagged defects. However, for the most part, and despite several meetings held, including with President Museveni, the contractor, has been brawling with UEGCL.
CIWEC executives previously told this newspaper that besides being vilified by UECGL, they have long desired to undertake corrective works, which is a prelude to receiving their last pay cheque, but the latter denied them access to the plant.
Blame gaming
UEGCL executives, on the other hand, maintain that CIWE, as per the contract, is required to have the Contractors’ All Risk Insurance (CARI) covering the contract amount of $568m (Shs2 trillion), equivalent to comprehensive insurance, and without it, they cannot be allowed to undertake major refurbishment.
“Things are already bad. If anything goes wrong, I’ll be the one blamed. I don’t want to go to Luzira because the contractor did not comply with the terms of their contract,” the UEGCL’s chief executive officer, Mr Harrison Mutikanga maintained.
In a February 24 letter to the Ministry of Energy Permanent Secretary, Ms Irene Bateebe, CIWEC Vice President Wang Yongtian lamented that they posted a CARI of $90m (Shs328b) running from April 1, 2023, to December 31, 2024, which the ministry was agreeable to but was rejected by UEGCL.
“However, through discussion via CIWEC’s broker with different insurance companies in Europe, United States, China as well as Sanlam in Uganda, all insurers responded that providing the CARI for the total contract amount is not acceptable with international standards and practices,” the letter reads in part. This is also in consideration of the fact that the 1 to 2 years of DLP expired.
CIWEC told MPs last week that on September 7, 2023, Ms Bateebe convened a meeting over the matter, attended by her team assigned to the project, UEGCL, and the Insurance Regulatory Authority (IRA), the insurance regulator in Uganda, during which the latter was requested to guide on the matter in writing.
Following IRA’s guidance, Mr Edward Baleke, the Isimba project coordinator in the ministry told MPs, that they wrote to the Solicitor General to amend the contract to allow CIWE to deal with maintenance without a comprehensive insurance policy.
“Our biggest challenge is that even then, when you look at the deployment (by the contractor) is minimal,” Mr Baleke noted.
UEGCL asserts that given the CIWEC’s insouciance and without the CARI, in the likely event that anything goes wrong during the maintenance works, government stands exposed to picking the tab.
At the heart of the defects are both minor and major issues, such as crumbling concrete under the water at the spillway gates that pose a significant risk to the embankment—the large concrete wall barricading the reservoir—on which the spillway gates sit and which forms part of the 10-storeyed dam house that includes the powerhouse and offices.
Isimba Dam has four spillway gates. A spillway gate is a raised adjustable gate to allow the controlled release of water downstream whenever water levels in the reservoir—the large lake behind the dam—increase[s], including the probable maximum flood.
Defects nightmare
During the committee meeting at the dam, there was drama after CIWEC paraded two engineering experts from Germany who argued that the erosion of the concrete beneath the spillway gates didn’t pose an imminent danger to the dam. However, the arguments by the German experts controverted their employer’s—CIWEC— admission. These contradicting statements irked MPs mid-last month and ordered the detention of CIWEC officials while appearing before the committee over the same matter.
According to UEGCL, spillway gates are ordinarily supposed to withstand even the strongest flood expressed in once in 10,000 years scenario. In this case, hydrological studies conducted, MPs were told that the water discharge flow corresponding to the 10,000-year flood event shall not be less than 4,500 cubic meters per second and to a 20-year flood event not less than 2,200 cubic meters per second.
Isimba Dam’s average water flow is 1,375 cubic meters per second. The increase in Laker Victoria water levels in 2020/2021, compounded by heavy rains across the lake basin, necessitated an increase in the water flow to 2,000 cubic meters per second triggering the erosion of the spillway gates concrete due to the heavy water flow velocity.
While CIWEC officials on their part defended they were not “responsible” for the rise in water levels that led to the over-flooding of the reservoir, experts sitting on the opposite side argued that changes in weather patterns ought to have been factored in during the designs. Also considering the one strong flood in 10,000 years scenario, the concrete should not be crumbling in the early years.
One Energy ministry engineer, speaking anonymously, told this newspaper that the dam's problems started at the designing stage.
Before that was the topsy-turvy Engineering, Procurement and Construction (EPC) tendering for the Karuma dam in 2011. The tendering process ensnared officials in several government offices, some highly connected, and commission agents around town to influence the awarding of the tender. Then came bribery claims.
When CIWE, one of the six bidders lost out on the Karuma tender to Sinohydro Corp, it was handed to Isimba as a remedial. No sooner had the construction of both dam projects which cost $2b kicked off than a bruising turf war between UEGCL and its parent ministry broke out over especially supervision. This is because several officials are reported to have picked bribes to close one eye during the supervision of construction works.
Halfway into construction, a litany of defects and claims of shoddy works unfurled pointing to negligence by both the contractors and government officials. UEGCL defends that they were handed supervision of the Isimba project in December 2016 when construction was nearly complete, at 75 percent. This was followed by the firing of the Owner’s Engineer (O.E), Energy Infratech Pvt Ltd, the supervisor of Isimba construction, for sleeping on the job.
The successor O.E, Artelia & Kkatt Consults, has also for the most part been at loggerheads with CIWEC. After putting both CIWEC and Artelia & Kkatt officials in one room and listening to their accounts twice, the chairperson of the Natural Resources Committee in Parliament, Mr Herbert Ariko, recommended the employment of a conciliator.
Divergent opinions
“We need a working group to intermediate on things because each side tends to think a superior view of each other,” Mr Ariko said last Tuesday.
One of the issues on which CIWEC and Artelia & Kkatt have brawled over is the diversion of water from the reservoir—to reduce water flowing through the spillways—to allow dry conditions for corrective works on the surface concrete.
CIWEC argues that: “None of the contract documents including the Tender design and the Employer’s Requirements carry any stipulations for the dry inspection and dry repair conditions for the Spillway, as clear from the scope of the civil works, the hydromechanical works and the electrical works.”
Artelia & Kkatt, on the other hand, maintain that “the spillway is currently not fit-for-purpose” and to allow the CIWEC to resolve the matter, the conditions for dry (re-)construction works apply as they were for the initial construction of the spillway.
The O.E further argues that a roadmap for achieving “such dry (re-)construction work environment, whereby upon such, the contractor has noted it shall perform the works” has to be drawn urgently.
“The design of the dam, civil, and structural features shall provide a 100-year service life, while the electrical and mechanical systems shall be designed for a service life of at least 40 years. The design service life of a structure or equipment is the period for which it is to be used for its intended purpose. Routine maintenance is anticipated but structural reliability and operational integrity shall be maintained. No structural element shall require refurbishment or replacement within the first 40 years,” reads in part a February report prepared by Artelia & Kkatt.
Last week’s conference with the parliamentary committee is one in a series of meetings that have been held since 2021 regarding urgently fixing the identified snags to avert a possible catastrophe. However, after every meeting and a report shared, all parties move on and the blame game begins afresh.
The Artelia & Kkatt’s resident project manager, Mr Marc Davies, indicated without a change in approach all efforts will go to naught.
“No matter how far we go on Isimba, some things have to change like change in approach,” Mr Davies argued.
For instance, despite the urgency of the matter, CIWE had indicated in their plans to embark on corrective works in March 2026 and complete them later in 2027. The company argues that based on engineering practices they have to undertake physical test models—a way of modelling and simulating systems that consist of real physical components—on the new designs for the spillway and further third-party adjudication before UEGCL/Ministry of Energy technocrats can be invited to Beijing for inspection. However, CIWE promised the same in 2022, only to go back in circles.
On Wednesday last week, Mr Ariko flanked by CIWE, UEGCL, Ministry of Energy, and Artelia & Kkatt’s officials gleefully addressed journalists at Parliament and announced putting their differences aside to fix the defects at Isimba. This includes CIWE drafting a schedule by April 20 for fixing the defects non objected to by Artelia & Kkatt.
The cost of fixing the defects including repairing the spillway, it was revealed, as well as securing insurance for the facility, is estimated to be no less than $150m (Shs547b). For CIWE, this is the source of pain. How are they committed this time around after talking about the same for four years, only time will tell. For Uganda, the thought of a dam accident is an unimaginable nightmare.
