Fertile Floods - Croatia's Wetlands of the Save

Every year, in the middle of Croatia, it's the same story: after the annual snowmelt, a huge flood wave spills out of the Alps toward Zagreb and Belgrade. This leads to an increase in the River Sava's water levels of some ten me-tres. The contents of more than ten billion bathtubs floods an area the size of Lake Constance, often for months on end.