It is no longer a question of if, but rather when the next flood will come. That is why low mountain valleys in Germany also have to prepare more for floods and floods. © pixabay – 1923196
Climate change is accelerating and the effects are becoming more and more visible. After the 2021 flood disaster in North Rhine-Westphalia and Rhineland-Palatinate, the question now is how communities in low mountain valleys can better prepare for more frequent and more intense floods. The KAHR project, funded by the BMBF, supports reconstruction and long-term disaster prevention on site with scientific expertise and 13 cooperation partners. The newly published KAHR brochure shows municipalities, electricity suppliers and emergency services how the electricity supply can be protected from heavy rain and floods in the medium and long term. The practical help was created together with the energy supplier Westnetz – including Westnetz employee Fabian Dolfus.
Mr. Dolfus, on over 60 pages you have spoken to other experts from the KAHR
Project a guide with crucial insights and practical tips
compiled. What are the three most important measures for this?
Power supply in the event of heavy rain or flooding and why?
Firstly, the weather situation must be monitored closely in order to obtain a precise overview of the situation and thus be able to react early. This is why an overview of the overall situation is so important so that you can accurately assess what measures need to be taken next. The primary goal is to get the situation under control as quickly as possible.
Secondly, in the event of flooding in flooded power grid areas, the power supply must ideally be switched off in a controlled manner shortly or immediately when the flood occurs. On the one hand, this ensures that no one is injured by an electric shock, for example. And on the other hand, it can be avoided in this way that automatic large-scale shutdowns by protective devices lead to a kind of “domino effect” and unaffected parts are also switched off.
The third immediate measure does not have anything directly to do with protecting the power supply, but is still extremely important: before the flood occurs, detailed warnings must be issued so that the affected people can get to safety as quickly as possible. To achieve this, climate-resilient communication structures must be built that can be supplied with electricity even in the event of a flood.
What advice do you have for municipalities that want to protect their power grids preventively? Where can they start?
In this work, we particularly focused on the Ahr Valley in Rhineland-Palatinate, which, among other things, was so badly affected by the 2021 flood disaster. But not only in the Ahr Valley but throughout Germany the question is no longer whether a flood is coming, but rather when the next big flood will come. It is therefore important to get a precise overview now of which parts of the power grid are in flood-prone areas. The supposedly rarer floods should also be expressly taken into account.
This means emergency plans can be drawn up more precisely and countermeasures can be planned and prepared in advance – as far as possible.
In addition, when planning the power grid, areas at risk of flooding should be avoided as much as possible. It is important to integrate such areas of the network into the rest of the power network in such a way that they can either be easily switched over during floods or can be supplied with electricity for even longer. Even after the flooding has ended, the affected areas should be able to be reconnected to the power grid more quickly.
What new insights have you gained about protection through the KAHR project?
the power grids gain?
The close exchange between science and practice has provided important new insights and the different approaches have shed light on the challenges from several sides. This has resulted in simple but very effective measures that make it possible to protect power grids from flooding in the long term. When installing cables, for example, they can be provided with an additional shrink tube so that less water penetrates the cable and thus reduces operational problems after a flood.
