Plastic pollution clogs hydropower dam in DR Congo

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"At the bottom end of Lake Kivu in the Democratic Republic of the Congo, a layer of plastic waste has gathered to the point of blocking the turbines of the east's largest hydroelectric power station. Thousands of bottles, cans and other rubbish thrown into the lake which stretches for 90 km along the border with Rwanda gather at the Ruzizi Dam causing problems for its operators. "

Every body of water has plastic garbage. But why is this the only dam in the world that has this problem?

But why is this the only dam in the world that has this problem?

Plastic garbage clogging Serbian dam threatens hydroelectric plant
Plastic waste has a volume of nearly 20,000 cubic metres
Thomson Reuters · Posted: Jan 06, 2021 6:09 PM ET | Last Updated: January 7, 2021

The floating landfill in Bulgaria has finally been cleaned up. A giant mass of rubbish clogged a dam on the Iskar river near the capital, Sofia, over two weeks ago. Nearly 600 tonnes of garbage and debris were discovered at the site.
Torrential rain carried rubbish from the capital and other nearby towns to a hydroelectric dam located 40 km away.

But today, fishermen in boats on the basin’s rivers are more likely to be foraging for garbage to sell, as the fish have long gone. Over the past 20 years, water quality in the Citarum region has been decreasing rapidly as pollution squeezes the life from the waterways. Every day thousands of tons of household garbage and untreated industrial waste contribute to this enormous drifting mass of rubbish, completely obscuring the river in many places.
The toxic waste kills the rivers, fosters disease, and clogs hydroelectric turbines.

Evaluation of Clogged Hydropower Plant Trash Rack Losses
Aleš Hribernik*
University of Maribor, Faculty of Mechanical Engineering, Slovenia
A trash rack is applied in front of the turbine to restrict the entrance of significantly sized material present in the water. It obstructs the free flow, and produces energy-losses by generating eddies induced partially by the trash rack bars and partially by the debris collected on it. While the additional static forces due to debris accumulation are considered in the trash rack design process, the debris caused energy losses taking place during plant operation are usually neglected, although a rather simple model was developed to account for them. However, the long term application of this model demands an extensive set of trash rack clogging data and, therefore, no such application has been documented so far. Thus, an analysis was performed to acquire the debris accumulation intensity with time and to evaluate the extra energy losses they caused. Data on one year operation of a hydropower plant aggregate i.e. flow rate and trash rack head losses measured at 15 minute intervals, were acquired and used to build a rack clogging model. Using this model, it was possible to distinguish clearly between debris and rack structure caused head losses, and to analyse different cleaning strategies. It was shown that cumulative debris contributed to almost one half of head losses although the rack was cleaned frequently. This shows clearly that debris caused head losses may not be neglected, moreover, debris removal has to be planned carefully and carried out efficiently. Analyses of acquired data confirmed that incomplete debris removal increased head losses by 18 %, and proved how important regular and thorough rake cleaning is. Moreover, it was found out that the actually applied periodical rake cleaning was not optimal, and that the circumstances required cleaning strategy performed much better. It resulted in similar head losses, while the number of rack cleanings was reduced by 60 %

Bureau of Reclamation
Technical Service Center
Design Standards No. 6
Hydraulic and Mechanical
Equipment
Chapter 12: Trashracks and Trashrack Cleaning
Devices
DS-6(12): Phase 4 (Final)
December 2016
Chapter 12 – Trashracks and Trashrack Cleaning Devices is a new chapter within
Design Standards No. 6. “Trashracks” was an existing subsection within
chapter 1 of Design Standards No. 7 and was revised by adding:
 Updated trashrack design process (last update was 1956)
 Trashrack cleaning devices

From what documentation did you draw the conclusion that the Congo dam is the only one?

you're projecting reams of text into what I wrote that are not there,

But why is this the only dam in the world that has this problem?

Indeed, the article authors should have provided this context. Otherwise, it's misleading.
Though, based on sheer size of Congo River, I suspect the problem is huge even compared to the precedents...