The Floods Directive calls for integrated plans, but we also found various other examples of integrated flood risk management planning in the analysed countries. The first thing that needs to be done is to determine the objectives of flood risk management. Objectives may be expressed in a joint vision of the future situation, minimum safety standards, or a certain risk reduction to be achieved. Questions that can be raised include: What level of risk is acceptable? To whom? And who is responsible for achieving this safety? Should the government protect citizens or should everybody protect themselves?
In all countries analysed in STAR-FLOOD public authorities have some role or responsibility in dealing with flood risk and in providing safety to their citizens. Yet, there are also large differences. One extreme is the Netherlands, with a government that is responsible for achieving high legal flood defence standards (applicable to areas that are protected by primary embankments from flooding by large rivers and sea). In most other countries citizens and businesses have more responsibilities themselves.
Figure 4.1: The adaptive management cycle (Pahl-Wostl 2007)
The challenge of selecting strategies and developing an integrated approach that avoids fragmentation is already introduced in Section 2.4 and the introduction of this chapter. This section provides some good practices on how to prioritise strategies and measures in integrated planning. Good practices on selecting the most effective and efficient measures for the phase before a flood are elaborated in Chapter 5.
A related challenge concerns complexity and uncertainty. We do not know the exact current flood risk nor how it will develop in the future. We also do not exactly know the effects of different measures, and their exact costs. Knowledge on these aspects is crucial for the planning process. A final dimension to consider is time. What measures should be taken when? Adaptive management (see Textbox 4.2) can help to deal with these challenges.
Textbox 4.2. Adaptive management as a way to deal with complexity, uncertainty and change
Adaptive management is a concept that has been proposed as a way of dealing with system complexity, uncertainty and change. It acknowledges that current knowledge will never be sufficient for future management. Therefore, policies are treated as hypotheses and their implementation as experiments to test them. Adaptive management requires a process of active learning by all stakeholders, and continuous improvement of management strategies by learning from the outcomes of implemented policies (Raadgever et al 2008; and see Figure 4.1).
Adaptive management may help in selecting and planning measures, and preventing under and over investments. It aims at developing robust and flexible management strategies that perform well under different possible futures and can be modified if necessary. This means starting with no regret measures and waiting as long as possible with measures of which the necessity and/or effects are uncertain. For more information on adaptive management, see also The Adaptive Water Resources Management Guidebook.
 The Adaptive Water Resource Handbook: http://www.newater.uni-osnabrueck.de/index.php?pid=1052
The good examples below describe how Sweden used climate change as a way to get flood risk management on the political agenda and to incorporate change; how French regions develop their own flood risk management plans; how the Netherlands and Belgium bring the concept of adaptive management to practice in their policies and how London prepares the Thames area for the future.
Sweden is a relatively low densely populated country with a low risk of flooding, at least for flooding that causes severe impact to the society. Although in recent years no serious or high impact events have occurred, the climate change threat creates public awareness. Authorities on the national and more decentralized levels assign money and other resources to plan more sustainably and resilient.
As a consequence of expected climate change impacts, new mandatory national standards for designing housing and infrastructure related to possible flood situations with higher return periods have been implemented. The use of BREEAM certification triggers this even more. It is a rating-system that gives lower ratings when a building is built in a flood prone area (in an unsustainable location). Predictions of what can happen visualised on maps are enough to influence economic investments and trigger more sustainable / resilient planning in Sweden.
Other countries can use the Swedish case as a good example. Providing information through mapping risks of climate change on a local and national level can improve awareness and trigger changes resulting in resilience through flood prevention (STAR-FLOOD Deliverable 3.5, see §8.2.1)
Figure 4.2: Flood depth at a modeled pluvial flooding before preventive measures in Södertälje at the 1/100 – year event (flood depth varies from 0 m to 3 m).
PAPIs (Programmes d’Action de Prévention des Inondations or Action plans for flood risk prevention) have been created in France since 2002 (Ministère de l’Écologie, du Développement durable, des Transports et du Logement, 2003). The aim of the innovative programme is that local authorities reduce flood risks by combining structural measures, like flood retention and flood defence, and non-structural measures like mitigation and preparation. More specifically, the programme’s objective is the implementation of a cross cutting flood risk strategy including the 7 following directions:
- Improvement of knowledge and risk awareness
- Monitoring and flood forecasting
- Flood warning and crisis management
- Integration of flood risk concern in urbanisation
- Actions for assets and people vulnerability reduction
- Flood retention actions
- Protection infrastructures management
The programme started with a first call for projects directed at all local authorities (municipality, intercommunality, ‘département’, region, and river basin authority) and based on the willingness of authorities to participate. Proposals for projects were validated using a list of criteria, and when approved by the ‘Mixed Flood Commission’ (Commission Mixte Inondation, a gathering of State, local authorities and civil society representatives) received the PAPI label. This label opens up the possibility for these projects to receive funding from the National Fund for Major Natural Risk Prevention. This contribution ranges from 20 to 50 percent of the required investment, depending on the nature of the operation. Each labelled project can also be funded by the Ministry of Environment. Every year the PAPIs are granted 300 million Euros for flood management measures. Each PAPI project is based on an assessment of the territory’s vulnerability for flooding. The results of the assessment are shared among and agreed by the involved stakeholders. Each PAPI is developed in partnership between the State and local authorities, led by a local authority and implemented by a broad range of stakeholders (State, local authorities, representatives of companies, farmers, NGOs). The PAPIs do not cover all areas with a potential significant flood risk identified during the first round of implementation of the Floods Directive. Yet, it is likely that the PAPI programme will be used in the future as a way to finance the measures required where possible. Initially the approach was designed for fluvial flood risk reduction only, but the measure was renewed in 2011 and extended to marine submersion too. Since 2011, the selection of the projects is done in the frame of a permanent call for projects. Proposals are checked by the State services and validated by the ‘Mixed flood commission’. Another authority (the Basin Comity) may do this validation for proposals requesting less than 3 million Euros.
Today more than 100 PAPIs are implemented in France. This demonstrates the success of this programme in encouraging additional action in a bottom-up and collaborative process. New measures are being implemented, preventing further development and preventing increase of risk in flood prone areas (STAR-FLOOD Deliverable 3.7, see §8.2.1).
Predictions of the consequences of climate change inherently contain uncertainties. To deal with such uncertainties, the Dutch Delta Programme has adopted an adaptive approach. An adaptive approach prevents over-investments and is based on no-regret measures.
Research done within the framework of the Delta Programme has shown the bandwidth of potential future peak discharges through the main river systems in the Netherlands. In the Delta Programme areas have been identified that are protected using regular spatial planning instruments. To be able to take measures in the future to deal with more extreme climate change impacts, certain areas should remain free of major developments. An example is the Rijnstrangen area in the east of the Netherlands that is reserved as it is possibly required after 2050 as additional retention area. Identifying these areas was done through scenario analysis.
Another example of adaptive planning can be found in the coastal village of Petten. Two alternatives to strengthen an existing coastal defence in Petten were possible: 1) strengthening the existing concrete dike; or 2) developing a flexible dike with loose sand. The latter option was chosen as it was more flexible compared to the concrete dike. In a scenario where sea level accelerates, additional sand can be supplemented in a cheap and easy manner. In a scenario where the sea level rises less quickly, overinvestment in a concrete dike is prevented. Another benefit of the flexible “soft” dike was the ability to create ecological habitats and opportunities for coastal recreation. Such Building with Nature solutions – of which the Sand Engine near The Hague is an even more knowns example – are more and more applied worldwide as flexible solutions (STAR-FLOOD deliverable 3.2, see §8.2.1).
Flood defence in the Scheldt estuary is mainly determined by the Sigma Plan of the Flemish government. The Sigma Plan combines three goals: accessibility of the river, flood protection and nature development. When fully implemented it is calculated that the basin will be protected against a 1/1,000 up to a 1/4,000 storm, depending on the location.
The plan involves a set of actions to be taken to reduce the risk of flooding. It include both local dike elevations (for example 90 cm in Antwerp) and room for the river measures. Some areas are de-poldered in order to give more room for the river. In addition, flood control areas that can be flooded in a controlled manner are developed. The measures combine flood protection with estuarine nature development. The plan makes use of existing spatial planning instruments
The Sigma plan is based on an expected sea-level rise of 0.60 m by the year 2100. Yet, it is uncertain if this expectation will become reality. Thus, when necessary the Sigma plan will be adapted by 2050 (STAR-FLOOD Deliverable 3.4, see §8.2.1).
Adaptive capacity in flood risk governance is necessary to ensure the continuation of effective flood risk management under uncertain environmental, climate and socio-economic conditions of the future in the scheme. In terms of flood defence, managed adaptive approaches are increasingly advocated for large-scale schemes. This requires the identification of trigger points and managing risk through pre-determined interventions, whilst instilling a degree of flexibility to adjust responses according to changes in conditions; the implementation of the Thames Estuary 2100 project is a good example of such long-term and multiscale planning.
Future concerns are also integrated within Catchment Flood Management Plans that support strategic decision-making over a 50 to 100 year timescale. This decision making is separated into three time horizons with their own themes:
- The first 25 years (2010-2034), which involves the continuation of maintenance, creating new habits – with a look towards the future and safeguarding space for future developments;
- The middle 15 years (2035 – 2049), which includes the raising and major refurbishment of many existing embankments, walls and smaller barriers;
- To the end of the century (2050-2100). The decisions in this stage will be adapted to the actual situation and the further future, using climate projections and expectations in that time period (see Figure 4.3).
Figure 4.3: Time horizons and themes in the Thames 2100 Scheme (EA, 2012)