Podeli

Time to rethink water management

The full extent of catastrophe that overcame Serbia and Bosnia recently is only now becoming apparent. Apart from the tragic loss of life there is huge damage to real estate, infrastructure, agriculture and industry. Serbs came together and made huge effects to prevent further damage and to save and help the victims.

The damage to the economy and society will probably amount to hundreds of millions of Euro. The rains that preceded the floods were of biblical proportions. Month’s worth of rains fell in several days. Dikes that were poorly maintained broke and constructions that were behind these dikes were submerged. Water runoff from hillsides unhindered due to soil erosion turned into devastating mudslides taking everything in their paths with them. Although this is considered a ‘once in a thousand years’ event, I think that the region due to climate change can expect more of this kind of extreme weather events in the future.

My country has a long history of devastating floods. The last major flood was in 1953 when a big storm combined with high tide caused dikes to break and the sea flooded a large part of country leading to 1,835 casualties and huge damage. Ever since then the focus was on keeping the sea out for once and for all and major fortifications were built. In the meanwhile, attention to the other traditional threat to the land –the rivers- was neglected until 1995 when the Rhine overflowed and 250,000 people needed to be evacuated. The system of dikes was weak and badly maintained. But that was not the only reason for the floods. One cannot continue to build dikes of ever increasing size. There is a limit to the capacity of what dikes can hold back. For centuries the country had relied on building bigger and stronger dikes and on straightening the rivers. The rivers needed to be tamed; side rivers needed to disappear. This was also done to create more land designated for settlement and agriculture. Swamps, peat land and marsh lands were dried and converted into agricultural land. These were major technological achievements and worked preventing floods and saving lives and livelihoods. Also Serbia has a history of straightening rivers, building dikes and converting marshlands into other land uses.

But it seemed that that system had reached its limits. Realizing these restrictions, the management policy of the national water boards regarding the rivers has shifted. While a system of dikes is maintained, rivers are now given space to expand. Rivers are made wider and flood plains are designated that in time of high water can be flooded by breaking the dike in order to take pressure of the river and protect urbanized areas elsewhere. Often these flood plains are on agricultural land and farmers are either compensated or their land is acquisitioned and permanently converted into flood plains and wetlands. Wetlands have important functions and provide important ecosystem services such as storm breakage and flood prevention, next to providing water purification, water storage and habitat for biodiversity. Not only is this a functional system; it is also more cost effective than building ever bigger and stronger dikes which are also expensive to maintain.

The recent events should be carefully analyzed but Serbia should rethink its management of the rivers and give the rivers ‘space’ by giving rivers room to expand and manoeuvre; by recreating side rivers and allowing these to meander; and by creating flood plains that in times of high water can be flooded in order to take pressure of the river and protect urbanized areas. A ‘once in a thousand years’ event is not to be allowed to happen every year.

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