Karuma dam nears light at the end of dark tunnel

A section of the Karuma Hydropower Dam. PHOTOs/TOBBIAS JOLLY OWINY

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For a project that was first conceived in 1999, emerging fault lines during the last 10 years have delayed completion and lifted the lid on the bureaucratic clumsiness seeping across government, writes Frederic Musisi & Tobbias Jolly Owiny

The construction of the $1.7b (Shs6.2 trillion) Karuma hydropower plant along the River Nile, which is expected to generate 600MW, was flagged off in December 2013 amid fanfare and expectations that the project will be completed within 60 months. The completion of the dam would connect rural communities to the national grid and engender Uganda’s march towards an industrial revolution.  

For a project that was first conceived in 1999, emerging fault lines during the last 10 years have delayed completion and lifted the lid on the bureaucratic clumsiness seeping across government.
By mid-this year, there was hope that the first 100MW turbine of the 600MW Karuma hydropower station, at the edge of Kiryandongo and Oyam districts, would be added to the national grid.

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It is a marvellous feat that both the Chinese contractor, Sinohydro, their employer—Uganda Electricity Company Generation Limited (UEGCL), and the construction works supervisor/Owners Engineer, AFRY Switzerland Ltd, frantically looked forward to. 

After all, the last four years have been strenuous for all parties as experts repaired defective works, especially cabling and corrosion of equipment that posed a threat to the Shs6.2 trillion infrastructure project that continues to lag behind the deadline for completion.
Earlier on, major cracks had emerged in the dam, which were blamed on the quality of water used in mixing concrete and the method in which the concrete was transported. The engineers also grappled with problems that arose as a result of the water pressure, which caused the concrete beneath both the spillways and spill basin to wear off. This led to stoppage of works for eight months in 2016 to establish and enforce corrective measures that lasted nearly a year.

The contractor was buoyant on commissioning the first unit of 100MW by December 2018 as per the project schedule. UEGCL and the Ministry of Energy were on the other hand fretting about the idea amid more glitches relating to electromechanical installations, especially cabling where by the contractor fitted wires not according to design standards or specifications applicable. 
The Covid-19 pandemic slowed progress at the dam in March 2020 and extended into 2021. Lockdowns brought industries to a grinding halt as the supply of several vital machines slowed. Due to the prolonged Covid-19 lockdown in China, engineering experts could not easily fly out to purchase some of these items.

This December Karuma hydro power station entered the ninth year of construction. The project now ranks among Uganda’s inordinately delayed construction projects alongside the 21km Kampala-Northern Bypass whose first phase started in 2004 from Bweyogerere/Namboole through Naalya, Kisasi, Kyebando, Kalerwe, Kawaala, Namugoona en route to Busega, with an initial completion date of 2005 but was completed in 2009.
“As a political appointee who serves a given term in any office. I would have been the first person to push for political commissioning of the dam,” Energy minister Ruth Nankabirwa said. “So, we said we are not going to rush the commissioning; we have to take the dry commissioning and technical commissioning until we are sure we are fully ready.”

Mr Paul Tumwiine, the UEGCL Deputy project manager for Karuma (left), addresses a team from Innovate UK at Karuma Hydropower dam on December 16, 2022. PHOTO/TOBBIAS Jolly OWINY

The technical (dry and wet) commissioning of the first units of the dam have been ongoing since April but failed to pass the litmus test. Dry commissioning deals with system functionality tests and during wet commissioning water is introduced in the turbine chambers to establish whether all integrated systems work flawlessly to generate electricity onto the national grid.
Ms Nankabirwa, who was named Energy minister mid-last year, added “What is true we had planned to bring on board two units/turbines, which means 200MW to the grid, but to do so we must be fully ready. So, when my engineers tell me that even the 200MW are not likely to come on board at the same time I listened.”

Coming apart at the seams
For the most part, it is the electromechanic drawbacks that continue to present challenges for the engineers.
On September 29, engineers at the plant commenced the process for wet commissioning for the first turbine—unit two; filling its chambers with water, which process ran until October 16 after which it was discovered that there were glitches with the tail race outflow tunnel (TRT) gate—the outlet for water from the turbine chamber.
The rise in water levels in Lakes Victoria and Kyoga in 2020 and 2021 flooded downstream with sand and other sedimentary debris that accumulated at the still basin where the TRT gates open. In effect, the gates could not open. A still basin is where the water inside the dam is pumped first to reduce velocity before it joins the Nile waters to flow downstream.

“A gate that weighs 20 tonnes weighed 50 tonnes as a result of sand and silt,” Mr Albert Byaruhanga, the UEGCL Karuma project manager, told Daily Monitor during a visit to the site last Wednesday. “This necessitated dredging and sediment pumping which we thought would take two weeks but took two months (from November into December).”
Another defect was detected during the running of the turbine. Engineers discovered a mechanical glitch with the ring gate— a primary safety feature—that surrounds the turbine runner and shuts off water in case of an emergency. When the ring gate was opened, it was discovered that there was “a synchronisation error” with one of the servo motors which control rotational motion.

This meant that the wet-commissioning process had to be halted and a probe was sanctioned to establish whether the all five turbines were experiencing a similar problem so that it could be fixed.
Last Wednesday, engineers embarked on watering unit two following the recent repair works. Water filling of the chamber to the required capacity ranges from a few days to a week after which it will be determined whether switching on the first turbine next month is possible.
Mr Byaruhanga says there is need for patience as the process of commissioning a dam is complex. 

“It is all about checking the functionality of all systems that make up the dam; be it de-watering, drainage, ventilation, air condition, emergency lighting, communication, data acquisition, et cetera. You need to make sure that all systems are working in an integrated manner,” he said, adding, “If there is a problem you stop, investigate the cause and fix.  The beauty is that the first unit is usually problematic, because you are encountering the problem for the first time. Once you figure out the solution you apply that on similar problems on other units.”
Notwithstanding, both UEGCL and the Ministry of Energy are confident that construction of the project is nearing completion, with current works reported at 98 percent.  They, however, cannot commit on specific timelines for commissioning the power infrastructure that ranks among the flagship projects of Uganda-China friendship.

Painstaking construction 
The reported multiple defects with the plant, and numerous investigations over the last five years by Ugandan experts, have shed light on the quality of works and structural integrity of the dam supposed to last 100 years. 
The defective works occasioned heated discussions that sucked in UEGCL, the Ministry of Energy, the Presidency, and the Chinese embassy in Kampala, and Sinohydro’s parent company, Power China in Beijing. The discussions threatened to strain the good diplomatic ties between Beijing and Kampala.  
Diplomatic sources told this newspaper they were edgy about Ministry of Energy officials and recently Prime Minister Robinah Nabbanja’s attempt to circumvent protocol by directly engaging the Chinese envoy in Kampala.
However, Ms Nankabirwa opines that the government will not cease in demanding for the qualitative completion of the dam.
“It is the name of the Chinese government at stake here if a project they finance fails to perform while we are supposed to pay back the loan,” she noted. “We have met with the ambassador and in each of the meetings agree on some actionable points. We learnt from those challenges and we would be fools not to learn.”

China’s Exim Bank pooled 85 percent or $1.4b (Shs5.1 trillion) of the project financing, following a March 2013 meeting between President Museveni and his Chinese counterpart Xi Jinping although the formal loan agreement was not finalised until mid-2015. 
The Ugandan government topped up 15 percent or $253m (920.8b). The Engineering, Procurement, and Construction (EPC) tender provided for two components; a hydro power station, and all transmission lines with their substations (400kV line from Karuma to Kawanda (Wakiso District), 132kV line from Karuma to Lira and the 400kV line from Karuma to Olwiyo (Nwoya District).
Consequently, in March, Power China buckled under pressure and replaced some of its staff with a new team.

“Our relationship has improved tremendously since and we have managed to overcome the previous challenges,” Mr Byaruhanga added.
Karuma dam construction kicked off in August 2013 but started in earnest four months later as the tendering process for a contractor was rocked by corruption claims and investigations by anti-graft agencies.  China International Water and Electric Corporation (CIWE) which was evaluated best bidder for the Karuma tender was short-circuited and the deal awarded to Sinohydro. 
The government then floated construction of the 183MW Isimba dam at the parallels of Kayunga and Kamuli districts to placate CIWE after it threatened legal action over procurement irregularities in the Karuma tender.

No sooner had construction of both projects at a combined $2b (Shs7.3 trillion) kicked off than a bruising turf war between UEGCL and its parent ministry broke out over supervision.  Three years after construction started, reports emerged of shoddy works by the two contractors as a result of using inferior materials and negligence by government officials supposed to supervise construction works.
In July 2016, the first eight-member ad hoc committee, that investigated claims of shoddy works on both projects, accused the contractors, among others, of using mild steel rod/ties instead of coupling, which are being cut at the concrete surface, and using concrete of inferior class in areas where it is likely to cause cavitation (voids) and scouring (wash-off or erosion of abutments).

Defects galore
About seven years ago, this newspaper published detailed exposés into dog fights between the then Ministry of Energy leadership and UEGCL over the management of the two projects. 
The fights sucked in several officials, including President Museveni, and exposed inaction on claims of shoddy works.
Mr Museveni eventually instructed UEGCL to take over the supervision of the two projects and the ministry remains with the role of oversight. 
He also named former Electoral Commission boss Badru Kiggundu to lead the project steering committee to oversee the construction progress of the two dams.

UEGCL officials inspect the Karuma Hydropower Dam switch yard. 

Since 2016, several independent engineering audits have been undertaken to ascertain the quality of works on Karuma. They unraveled, among others, environmental, health and safety concerns for workers, quality control defects in the concrete mix designs and alignments of some of the tunnels.
“Our principle now is that whenever we encounter a challenge we do not move forward until that snag is fixed,” Ms Nankabirwa said, adding, “when I came here, I found a lot of issues/snags; on cabling for instance, where the contractor was just bundling them together and not going by specification. So, we said we are not going to rush for political commissioning. We decided that we have to go through several takes of technical commissioning until everything is satisfactory.”
Mr Byaruhanga revealed that during the subsequent years they have been fixing all the gaps identified.

In 2021, he said, the government team had engagements with Sinohydro and executives from Power China to address all technical glitches.
“It was agreed that the contractor starts addressing the issues raised. In terms of mechanical work, we have had to do replace about 80km of optical cables and 18km of fibre optics, which is a lot of work but we are now satisfied with what has been done. There were other issues with earthing, oil units, hydraulics, gate structures, among others, which have been addressed and additional remedial works are ongoing.”
Looking back at the last tumultuous years, Mr Byaruhanga said there is good progress registered.

“Back in 2018, the contractor had given the impression that he could continue with the commissioning of the dam and address the problems simultaneously but our view was that that would require extensive shutdown periods of the plant,” he added.
 “Generally, on the defects we look at three things; safety—you have an underground plant with electrical components, transformers, generators, and assuming there was a catastrophe there would be dire consequence but how do you deal with that? Second is operability—you are looking at the operation and maintenance phase; how easy is it to carry our preventive maintenance of the various sections with ease. 

If you don’t have ease, it means having lengthy shutdowns to allow repairs and each piece of work that would take an hour or so would take days and that is not efficient. The third consideration is preventing loss of generation revenue; each time the plant is shutdown you lose revenue and that affects the ability to pay back the loan,” he added.
The flooding incident in August on the Isimba dam after one of the radial gates malfunctioned thrust the supervisors, UEGCL and Ministry of Energy officials into the crosshairs after government borrowed colossal sums of money for the construction of Karuma and Isimba dams on stringent conditions that placed the country under debt bondage.
On a positive note, Uganda Electricity Transmission Company Ltd (UETCL) has completed works on all four power substations and transmission lines before the commissioning of the dam.

 Mr Michael Taremwa Kananura, the UETCL acting managing director said works on the Karuma, Kawanda, Olwiyo and Lira power substations are complete.
 “The moment Karuma Dam is ready to generate, we shall evacuate without delays because Karuma-Kawanda (400KV) and Karuma-Olwiyo (400KV) lines are complete. It is only the Karuma-Lira line that is not yet complete, we are remaining with 2.8km of stringing and which we are confident will be complete by December 15.”
 

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