Isimba staring at Shs5b error

Monday’s flooding of the Isimba hydro-power dam leading to its temporary shutdown was as a result of “human error”, Saturday Monitor has learnt.

The flooding, multiple sources confirmed to this newspaper, happened when an absent-minded Uganda Electricity Generation Company (UEGCL) engineer inadvertently opened the radial outflow gates instead of the inflow gates, causing water to spurt inside the powerhouse to near submersion.

The powerhouse—that houses generators and turbines and other electro-installations requisite hydro-mechanical and electro-mechanical equipment for electricity generation—is laid in the riverbed.

Isimba is a run-of-river type dam. It harvests energy from flowing water from the adjoining 170 million cubic metres reservoir to produce electricity.

The UEGCL’s engineers were undertaking routine maintenance on Monday when possibly one of them opened the wrong gates, leading to a gush of water submerging machines.

“It was slip in procedure[s] that led to the flooding,” one source intimated, adding that the lapse could cost upwards Shs5b.

On Thursday, Ministry of Energy officials dashed to the site of the stricken dam to assess the full impact of the accident. A joint technical team was established to look into, among others, the probable cost of machine repairs.

It was also decreed that only Energy minister Ruth Nankabirwa shall respond to all external inquiries. She was not readily available by press time.

The 183 Megawatts Isimba dam, located at the parallels of Kayunga and Kamuli districts, was commissioned in March 2019. The dam has four Kaplan axial flow turbine generators that were submerged, each with a capacity of 45.8 Megawatts.

It remains unclear when the technical glitch will be addressed, but the monopoly distribution service provider, Umeme, warned early this week that areas around greater Kampala Metropolitan, as well as parts of the eastern and western Uganda, could be hit with power blackouts of up to eight days.