Pilot Project Den Helder
A dyke collapsing near the Helderse Zeewering sea wall will cause the entire city centre of Den Helder to become submerged under two metres of water within 12 hours. A collapse near Huisduinen will cause slightly less damage because of the more shallow depth. The Security Region does not have a flood evacuation plan in place, because the number of variables is too large.
This multi-layer flood risk management pilot project has explored options for linking up dyke improvement with other policy fields. In the majority of cases, this has yielded area-specific solutions that call for a tailored approach. The phased realisation of a climate dyke, with residential and storage functions in Den Helder, will enable the water tasking to hook up with the improvement of spatial quality.
Results
The dyke on the north side of Den Helder carries the highest flood risk. The main insights from the pilot project provide the following picture:
- Short-distance evacuation offers the best chance of success;
- Factoring in flood risk management in spatial developments; the multi-layer flood risk management tool provides insight into costs and benefits;
- Utilities are not water-resilient;
- Knowledge of “vital and vulnerable” is still limited; policy is required;
- Mindset: redundant emergency network and water-resilient distribution stations;
- Attention to self-sufficiency; importance of water-awareness and coping capacity;
- Long-term vision calls for other administrative culture (timeline approach);
The study into multi-layer flood risk management requires attention to be paid to expanding the options for preventive evacuation and the (spatial) options for the coping capacity of individuals. The essential distribution stations would need to be made water-resilient. The municipality and its residents should be provided with options for self-sufficiency with respect to energy and drinking water. Assessment procedures for essential facilities need to be developed, as do plans for the recovery phase.
The Nieuw-Den Helder district plans to create new structures for public spaces in elevated and dry areas, such as the edge of the dunes and the forts. Undesirable (visual) barriers must be removed. In the city centre, attention also needs to be paid to the accessibility of elevated locations and storied new urban development to enable vertical evacuation.
A timeline needs to be drawn up showing already scheduled activities and measures, in order to map out opportunities for linkage with other relevant domains in the area-based processes. The Measures Matrix must be used as a source of inspiration for the joint design explorations, rather than as a checklist for measures.
The municipality, district water board, and the province must set down administrative agreements, in collaboration with the Security Region, to substantiate policy – including for the long term. As yet, the regional parties are still insufficiently familiar with multi-layer flood risk management: communication, jointly developing strategies, and sharing responsibilities is essential.
Residents must also be made aware of the possibilities of multi-layer flood risk management. They may be involved in the creative process. National and regional policy must be elaborated for the vital functions, in collaboration with the utility companies, directed by an independent body, with an independent evaluation of interests, and with insight into the costs and benefits. The Province will ensure that the results of the pilot project are incorporated into the Environmental Vision. The city of Den Helder aims to include multi-layer flood risk management in its planning; the Woningstichting housing organisation wishes to factor in the ideas from the pilot project into the Nieuw-Den Helder restructuring, providing architects with preconditions. The district water board is using the insights gained in the implementation of the Water Review, and plays an active role in the discussion on multi-functional and regional flood defence systems. At the regional level, a long-term strategy is needed to foster the coping capacity of individuals and an adequate approach to vital and vulnerable functions. External incentives, from policy or the Delta Decisions, are needed to encourage all the parties (such as KPN telecommunications and Liander power company) to actively participate. Attention needs to be paid to complete the information and make it accessible; for example, the exposure map and the risk map. Increasing the coping capacity of citizens requires instruments other than risk maps.