by Ilan Kelman
Buildings in Moss' city centre in the floodplain (photograph by Ilan Kelman)
Looking back over past centuries, Norway, as with many other countries, has long experienced major river flood catastrophes. Several hundred died along the Gaula River in 1345. In eastern Norway in 1789, flooding killed over 70 people.
Fortunately, river flood deaths have been rarer in contemporary times though threats are still frequent. Most problems are property disruption and damage. Part of the reason is that we own more to be damaged.
Part of the reason is Norway’s tradition of managing rivers by relying on walls–dams, levees, and dikes. When (not if) a wall’s flood design limit is exceeded, the land behind it floods. People are unprepared because they thought that they would be protected.
Instead of forcibly separating people and water, why not let floodplains–called that for a reason–do their job? Let rivers behave as rivers, spreading out when it rains or when the snow melts. Use walls occasionally or as a part of flood risk reduction, but don’t rely on them for everything.
River floods are part of Norway’s environment. They are a natural process. When humans get in the way of floods, then disasters happen. We can stop disasters by permitting floods.
The author: Dr. Ilan Kelman is Senior Research Fellow, Center for International Climate and Environmental Research – Oslo (CICERO).
Kelman I and Rauken T 2012 The paradigm of structural engineering approaches for river flood risk reduction in Norway Area doi: 10.1111/j.1475-4762.2011.01074.x
Sandelson M 2011 Norway storms isolate thousands The Foreigner 27 December