Comments by "N Velsen" (@nvelsen1975) on "Storing Freshwater In The Salty Sea" video.

Also it matters when we're talking. In the 1970's the rivers were absolutely putrid from industrial pollution, but manure-dumping by rich farmers hadn't really taken off yet. In the 1990's manure-dumping by rich farmers is a huge problem, with layers of 10 - 15 cm deep being dumped just to get rid of it and the water bears it all in the end, but anti-pollution measures for industry were beginning to work. Around now there has been another 30 years of manure pollution build-up, but at the same time, reduction in industrial pollution has fully filtered through the system. So the water changed over time. This is very important as the horrible water quality in many lakes is a direct result of the farmers dumping excess manure. Stuff like Cyanobacteria (Blauwalg) was never a problem in the early 1990's, that's only now because of farmers poisoning the rivers.
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