aleksandr chistya kov has been monitoring the dnieper in ukraine for years.owing us what's known as blooming. it's when too many nutrients get in the water, triggering a rapid, lurid green growth of algae. outside the cities, the run—off from fertilisers used in farming is also a big part of the problem. as is untreated waste. of course, if fertilisers and waste is dumped in the rivers, it means pollution when those rivers then flow into the black sea. three rivers provide the bulk of the black sea's pollution — the dnieper, the dnister and the longest of them all, the danube. back injune, the water quality reached the headlines in ukraine. a combination of rain and hot weather near odessa was turned into a nutrient rich pea soup. anything that swam in it turned green. these women work for odessa's sanitation department and test the black sea every monday. this year, they advised holidaymakers not to swim through most of the peak month of august. not that it put many people off. you're not worried the water is not clean? no. and when the authorities say the w