Delay in Isimba Dam repairs could be catastrophic, UEGCL warns
Isimba Hydro Power Plant (HPP) is located 4km downstream of Simba Falls on the River Nile. PHOTO/COURTESY
What you need to know:
- Dam failure looms if Isimba repairs drag on – UEGCL sounds alarm
Officials from the Uganda Electricity Generation Company Ltd (UEGCL) have warned that the continuous defects at the Shs2.2 trillion Isimba Power Plant, if not handled early, may turn disastrous and lead to the dam's failure.
The UEGCL chief executive officer, Mr. Harrison Mutikanga, told officials from the Inspectorate of Government (IG), led by IGG Beti Kamya, that the contractor’s continuous delays in fixing the dam’s spillway pose a huge risk.
He added that if these issues continue in the next five years, it may result in a dam failure and total power plant shutdown.
“A dam failure would be catastrophic because of the downstream communities, activities happening there. Our appeal is that the contractor needs to carry out effective repairs and maybe look at a long-term solution, which can probably be building a new spillway because there is also an issue with the spillway,” he said.
The dam was constructed by Chinese firm China International Water and Electricity Corporation (CIWEC) at $568 million (Shs2.2 trillion), of which 80 percent was a loan from the Exim Bank of China.
CIWEC was given an Engineering, Procurement, and Construction (EPC) contract to build the dam.
An EPC contract, according to Mr. Herbert Kato, a senior officer at the Ministry of Energy and Mineral Development, is a type of contract where a contractor undertakes the entire project, from design and planning to procurement, construction, testing, and commissioning.
Barely two years after its completion and commissioning by President Museveni on March 22, 2019, officials say the plant developed defects in July 2022, prompting the Energy Ministry to task CIWEC to undertake repairs.
Daily Monitor on September 5, 2022, reported that these defects worsened in August 2022 when a worker opened a wrong gate during maintenance on Unit Three, causing the automated gate to jam and a flood to submerge four floors, including the powerhouse.
This led to a power blackout, and engineers, IT specialists, and cleaners worked frantically to restore operations on August 11.
Each turbine unit has a generation capacity of 45.5 megawatts (MW), but only three have been active since the dam's commissioning.
Officials from the Energy Ministry, led by Minister Ruth Nankabirwa and Permanent Secretary Irene Batebe, pitched camp at the site to supervise repairs.
Mr. Mutikanga told Ms. Kamya, who visited the plant on Friday, that the contractor, upon discovering defects, conducted emergency underwater repairs.
"But you all know that doing reworks underwater helps but is not very effective because subsequent inspections in September and December still indicated that the dam spillway concrete continues to erode, and there are cracks in the joint seal. That poses a serious problem," he said.
He explained that if water leaks into the foundation of the concrete basin, it could lead to hydraulic jerking, lifting the concrete slab and causing backward erosion that could collapse the dam.
"When you have a spillway unlikely to handle flood design capacity and more rains, it becomes a serious worry," he added.
President Museveni officially commissioned the Kayunga-based plant in 2019, with its concrete structural designs expected to last 100 years and electrical designs 40 years.
IGG Beti Kamya
Mr. Kato emphasized that the dam was designed for three purposes: normal operations, longevity, and emergency handling of rising water levels.
He said that while the dam currently generates power, the longevity aspect is now in jeopardy.
Mr. Mutikanga confirmed that despite the defects, all machines are functioning, and the plant is producing enough power to have repaid more than half of the $568 million loan.
However, he stressed that the defects, if not urgently addressed, threaten the plant's lifespan.
The contractor was given two years to fix the issues, but several extensions have been granted without visible progress.
"If the contractor does not fix these defects in time, the functionality of the power plant will be compromised," Mr. Mutikanga warned.
"The major defect is the dam spillway, and it is a dam safety risk which could result in dam failure."
He said UEGCL is considering terminating CIWEC’s contract if no substantial repairs are done.
"They acknowledged the problem but are too slow to act," Mr. Mutikanga said.
Officials from CIWEC did not address the media after a closed-door meeting with IGG, UEGCL, and Energy Ministry officials on Friday.
Earlier this year, four CIWEC officials were arrested by Parliament Police after refusing to accept liability for the defects during an interaction with the Natural Resources Committee.
This contradicted earlier CIWEC reports acknowledging the need for urgent repairs.
It remains unclear what CIWEC officials told Ms. Kamya during the Friday meeting.
She said a detailed report would be produced in three weeks to guide her next steps.
"However, the lesson we learn is about how EPC contracts are awarded. They give the contractor too much power," Ms. Kamya said.
"Personally, I am not impressed by what I saw — a building that is only five years old looks much older."
