Placing flood mitigation on four pillars: Conclusions from 2013 central European floods

In their position paper the flood researchers warn against the illusion that if only sufficient funds are invested, damage caused by flooding could be cut to around zero. Economists, geographers and landscape planners at the UFZ write: "There is no way we can provide blanket protection against flooding. A residual risk of damage will always remain, for instance if the dikes break. The conception of 100% flood protection is just as fallacious as the idea that future damage can be prevented as long as plan approval procedures are expedited and public participation curtailed. We do not need less dialogue, we need more, centring on the question of how we should best prepare for extreme flooding in the future"; they propose that, in future, flood mitigation measures should be based on four pillars to keep damage levels as low as possible and to distribute the burden fairly:

1. Technical flood protection

In Saxony alone, over half a billion euro has been invested in technical flood protection since the catastrophic flooding of 2002. Approximately one billion euro is planned for concrete walls and levees, etc., earmarked for investment by 2020. Local government authorities and residents hope that the areas they live in will be better, perhaps even completely, protected. In a representative survey conducted by UFZ in 2005 among 404 households damaged by the flooding in 2002, over 60% of the inhabitants of three municipalities in the Mulde hinterlands agreed with the statement that levees convey a sense of security. "But this enhanced sense of security comes at a risk. There is more building development than ever before. And if the walls break or overflow, the subsequent damage will just be greater," reports social geographer Dr. Christian Kuhlicke from UFZ, who analysed the consequences of the Mulde flooding in Eilenburg and Grimma. "This is another reason why it is short-sighted to trust only in technical protection."

2. Natural flood protection by providing rivers with more space

Throughout Germany, two thirds of the former floodplains have been lost to dikes and other flood protection measures. The situation along the major rivers such as the Rhine, the Elbe, the Danube and the Oder is in places even more dramatic. Some sections have held onto a paltry 10-20% of their former alluvial floodplains, kept available as flood zones. But in addition to purifying the water, these floodplains fulfil an important role during emergencies: they retain the water for as long as possible within their boundaries, hence alleviating flood peaks. Just a few centimetres can be enough in places to decide whether a protective wall and the built-up area located behind it are flooded or not. If all of the dike relocation projects currently under discussion along the German Elbe were to be carried out, the flood waters would have over 23,000 hectares, or in other words one third more, of additional space to spread across. "Although planning has progressed really quite a long way along the Elbe (approx. 700 hectares have been completed, a further 2600 hectares are in the concrete stages of planning), implementation of these projects have proven exceedingly time-consuming and a drain on resources. After all, the surface availability must be agreed just as much as the new dike lines, and agricultural repurposing in particular needs clarification," explains Mathias Scholz, expert for floodplains at UFZ. The first expansive project of this kind is the dike relocation at Roßlauer Oberluch (City of Dessau-Roßlau) in the Central Elbe Biosphere Reserve. Following over a decade of preparation, the State of Saxony-Anhalt reactivated approximately 140 hectares of floodplain here by relocating the dike in 2006. UFZ provided scientific monitoring for this project, as dike relocation in this manner offers the opportunity of combining sustainable and modern flood protection with nature conservation objectives and hence of safeguarding resources for future generations

3. Private precautionary measures- don't just demand, subsidise also

The Federal Water Law already specifies that those potentially affected (are) "obligated within the framework of what is possible and reasonable to undertake suitable mitigation measures in protecting against the hazards of flooding and to reduce the damage thereof, in particular to design the use of properties to consider the possible deleterious implications that flooding may have on human beings, the environment or material assets." However, this demand will remain nothing other than simple theory without the introduction of concrete obligations or economic incentives. At the same time, technical protection structures reduce the expected damage and hence the efficiency of additional private precautionary measures. "Private mitigation tends to be effective and efficient wherever there is no, or inadequate, protection in the form of technical flood protection," explains UFZ economic geographer Dr. Volker Meyer. If responsibility for flood protection is increasingly reassigned from the public sector to those potentially affected, citizens become managers of their own risks. "How many of them invest in flood protection as a result is not dependent merely on how high they perceive the risk to be, but also on the resources they have at their disposal. Who will be able to afford which (individual) level of protection in the future? What happens to those who are unable to afford protection?" This is why in their statement, the UFZ researchers recommend the subsidisation of private precautionary measures -- for instance in the form of low interest loans, conditional on the building measures, i.e. refurbishments, providing protection against flooding, or in the form of reduced insurance premiums.

4. Mitigation-based, mandatory insurance

Nevertheless, even a combination of technical, natural and private mitigation to protect against flooding will not succeed in preventing all damage -- 'residual risks' remain. And although immediate aid such as the current 8 billion Euro programme by the German Federal and Länder Governments alleviate suffering, they do not help solve the crux of the problem. "Mandatory insurance for all home-owners would reassign the costs for damage within a framework of solidarity, while the premium rebates would create economic incentive for private mitigation measures to tackle elementary damage such as flooding, severe rainfall and snow pressure," prompts Prof. Reimund Schwarze from UFZ as food for thought. The calls for mandatory insurance are not new. The German government considered introducing a mandatory insurance for elemental damage in the wake of the 2002 flooding. Regrettably, this endeavour floundered on the bureaucratic merry-go-round and collective forgetfulness. But this did not provide those worst affected with any sustained alleviation. Although roughly every third house is currently insured against elementary damage, 1.4 percent are located in areas that statistically speaking are flooded every ten years and are hence deemed 'uninsurable'. Accordingly, in the region of one million people have no chance of acquiring regular insurance coverage. Policies are 'reviewed individually' after every major incident -- such as 2002 in Dresden -- often ending up more expensive than they had been before. Climate change places an additional burden on the availability of insurance policies, as additional areas are spreading into 'uninsurable' zones. "It appears appropriate, therefore, that there should be a degree of solidarity in a model of mandatory insurance. In this, a carefully structured, mandatory insurance can assign the costs of actual damage in such a way that the economic incentives for mitigation measures against flooding and heavy rainfall are not lost. A mandatory elementary damage insurance would ensure that extreme, rare or local incidents such as flash floods, earthquakes or land subsidence would become comprehensively insurable," says climate economist Prof. Reimund Schwarze as a summary to his analysis of catastrophe mitigation.

The scientists believe that a public debate is now necessary to determine how much responsibility the state should accept and how much should remain with the residents of areas at risk of flooding. Not only public debates on single local protective measures are needed; what is also needed is a broader societal discussion on the risks that a society and its citizens are willing to carry in connection with flooding and how the costs of mitigation measures should be distributed.