The proposed guidelines for the flood adaptation strategy are illustrated using two European countries, Poland and Norway, as case studies. Poland has followed the EU recommendations on adaptation to floods (European Parliament, Council of the European Union 2007). Norway does not belong to the EU, but has developed a flood adaptation strategy based on the knowledge of the expected effects of climate change on floods and national policy instruments already in place to reduce flood damages. The current flood adaptation strategy in Norway includes guidelines on how to consider the climate change impact on floods. In Poland, according to the Strategic Plan for Adaptation to Climate Change (SPA 2020) created byMinistry of the Environment (IOŚ-PIB and KLIMADA 2013) the frequency, magnitude and extent of the extreme events will increase. However, until present, flood risk management plans do not take into account the impact of climate change on floods in Poland. Moreover, the adaptation policies and laws in Poland have never been assessed from the point of view of their role in a strategy of adaptation to floods in a changing climate.
Flood risk assessment: flood hazard and risk extent in present and future climate conditions (step 1)
The iterative nature, of the directives of European Union in case of flood risk management allows for the updating of flood hazard, flood risk assessment and flood risk management planning in Poland. In Poland, the preliminary flood risk assessment qualify the catchments to more detail analysis. Within this step, base of available at that time data, the choice of 253 catchment has been made. The further analysis result with hazard maps which include flood extent (the area of inundated land), water depth, the elevation of the top-point (crown) of embankments (Fig. 2) and where appropriate, the velocity in a separate map (Fig. 3). The upper and lower parts of presented maps have a different hue (Figs. 2, 3 and 4) which is caused by the difference in lightening of the scanned surface.
Flood hazard maps were prepared for three different flood return periods: short (≥10 years), medium (≥100 years), presented below and long (≥500 years). On the basis of flood hazard maps with addition of adverse consequences for society, economy and environment the flood risk maps were prepared for the same return periods.
Due to the large economic value of highly urbanized and densely populated areas, it was considered that velocity of flood water distribution should be included in separate hazard maps. Additionally, the Polish Water Law requires that areas where there is a danger of destruction or damage of the embankment, dams or protective structure of the technical zone should be included in the flood hazard map.
In Poland flood risk maps are divided into two groups. The first group presents the flood risk in terms of adverse consequences for the environment, cultural heritage and economic activity. The important content of the risk maps in Poland are nature conservation program areas. Nature conservation program areas became a problem for water management decision making bodies because some flood adaptation measures are prohibited in restricted areas. The second type of maps include adverse consequences for people and flood losses. The estimations of flood losses were only carried out in areas where data from the surveys were available. Other areas were classified according to the depth of flood on private residential buildings and buildings of social use.
Norway follows its own approach of flood risk management. Flood hazards and flood risk maps are replaced with a combination of flood hazard and flood risk maps called flood inundation maps (Fig. 5). Maps have been developed for approximately 130 river reaches with a high flood risk. Figure 5 presents an example of a flood inundation map prepared for Naustdal in Norway. The map contains the extent of flooded area with a certain probability of flood occurrence (in our example 0.5%, i.e. area that will be flooded by a 200-year flood), and the value of a depth of water on flooded area. The classes of water depth are classified for each 0.5 m, up to 2 m depth. Norwegian maps also include the buildings that only will have water in the basement and buildings prone to severe damages from floods.
However, calculations of the adverse consequences for the environment, cultural heritage, industrial business and private property of people are not evaluated directly in flood inundation maps, even though the existing buildings and infrastructure are included in the map.
The impact of future climate change is an issue that has not yet been considered on Polish hazard maps or risk maps, but is included in the Norwegian maps. Hydrological projections for floods in Norway under a future climate (Lawrence and Hisdal 2011) and (Hanssen-Bauer et al. 2015), are accomplished by ensemble modelling based on locally adjusted precipitation and temperature data from several regional climate models, in conjunction with multiple hydrological models for more than 115 individual catchments to assess likely changes in river floods.
Flood hazard maps together with flood risk maps provide basis for the proposal of the way to reduce the risk of flooding in Poland, in other words, form a basis for the development of flood adaptation scenarios in a framework of flood adaptation strategy.
Building the adaptation scenarios: methods of flood risk management, application of physical measures and spatial planning (step 2)
Building the adaptation scenarios means preparation of a set of possible scenarios of consecutive adaptation actions regarding control measures and adaptation measures.
Control measures consist of flood water transfer, flood proofing of buildings and technical infrastructure, drainage and pumping systems, flood water storage and channel conveyance and capacity. Adaptation measures include land use and river corridor management. Land use management consists of spatial planning, an infrastructure and a categorization of land cover. The set of criteria for defining the scenarios of adaptation to floods in future climate conditions should be based on future climate projections, economic growth projections, and projected population growth. In particular, under present Polish and Norwegian conditions, not all above listed criteria are introduced to the urban planning and there is a problem of dealing with the uncertainty of flood risk.
The Norwegian Report on Adapting to climate change (NOU 2010) acknowledges that providing too much flexibility allows for appropriate local planning decisions but at the same time allows local planners to ‘opt in or out’ of implementing climate change measures, depending on their willingness or ability.
Unsustainable development of river side areas exists both in Norway and Poland. In Poland, insufficiently balanced planning regulations are one of the reasons of that situation. In addition, audits of Polish Head Audit Office (NIK 2013) have shown that spatial planning has not been sufficiently or effectively used as an instrument to reduce flood risk. Unsustainable development of riverside areas is assumed to result from a lack of:
Inappropriate spatial planning causes the devaluation of private and public property including the national heritage. For this reason, it is important to address methods of protecting existing and planned housing areas in Poland, including infrastructure and the condition of water control structures. Franczak et al. (2016) proposed a method for the preliminary evaluation of flood hazard maps by a comparison of historical water extents and the flood hazard extents which results with the conclusion that the extents for medium size catchments are underestimated. The authors also raise the issue of high vulnerability at local scale (catchments <50 km2) where flood hazard areas are not defined but frequent flash floods increase the risk and possible urban flood losses. IPCC (2013) highlights the importance of increasing frequency of flash flood events in Europe in future climate which leads to the conclusion that also small catchments should be included in spatial plans for the future. This issue raises the following questions:
Because there are no restrictions on building in floodplain zones in Poland and prices of land near river side are competitive, the amount of housing in those areas has increased. With increased housing in inundation areas, the cost of flood losses has also increased and is almost entirely paid by the public because private “insurance in case of flood” is not obligatory and not popular in Poland. In a result, houses are often renovated or rebuilt in the same place where flood occurred.
In Norway, the technical guidelines of the Planning and Building Act (PBA) for new buildings have introduced different safety classes based on flood recurrence intervals; 1-in-1000 year for flood hospitals and schools, 1-in-200 year flood for living houses and 1-in-50 year flood for barns and garages. In addition, it is stated that climate change has to be taken into account in spatial plans. Following these needs, the Norwegian Water Resources and Energy Directorate (NVE) has developed guidelines on how to take into account floods in spatial planning. Due to the uncertainties in the projections for individual catchments and the need to generalise the results to areas outside the calibrated catchments, a pragmatic solution was to propose three categories for use in climate change adaptation: no change, 20% increase and 40% increase. The future climate variability in the example in Fig. 5, is taken into account by increasing the 1-in-200 water level quantiles by 20%.
This also includes streams and rivers where no flood inundation maps exist. A separate chapter of the PBA is devoted to climate change adaptation. To increase the knowledge amongst spatial planners in the municipalities, the regional offices of NVE arrange workshops to inform the municipalities about existing laws and regulations, tools and information that can be used to consider flood risk in spatial planning.
This has raised the awareness and improved spatial planning, including considering the climate change effects on floods. The Norwegian PBA is an example where the technical guidelines state that climate change has to be taken into account in the spatial plans.
Changes of the flood risk in Poland and Norway can be monitored by adaptation measures described in climate change reports (NOU 2010; IOŚ-PIB and KLIMADA 2013). The measures of adaptation in Poland include e.g. the percentage of the country area included in spatial planning (26.4%), the development of flood risk plans, the existence of regional and local weather-agriculture monitoring system, the development of a “vulnerable infrastructure monitoring system” an emergency communication module, participation of national and international funds in the adaptation financial system, and a value for flood losses (in PLN and % of income per capita). The adaptation measures in Norway include the development of local planning capacity, also in financial area, planning with the respect of climate change uncertainty, development of a solid, knowledge based monitoring system, development of knowledge referring to climate change, enhancement of administration capacity, and the improvement of international cooperation and national coordination in adaptation process. Both Polish and Norwegian strategies for spatial planning stress the need of appropriate legal regulations relating to planning and building as one of many steps towards ensuring safety along the riverside and reducing flood losses (NOU 2010; IOŚ-PIB and KLIMADA 2013).
In Norway, both houses and infrastructure have been built on flood prone areas throughout history because of inappropriate laws and regulations in the past, economical reasons or lack of knowledge. NVE is responsible for funding flood safety measures throughout the country. New measures are prioritized based on the cost benefit analysis that also considers flood risk in a future climate. To include climate change impact, each adaptation scenario built within the model led river system will undergo simulations driven by an ensemble of future climate projections.
Choice of scenario: recommendation for the future (step 3)
The choice of scenario of adaptation is an essential point for further implementation. The choice should be done according to the criteria, such as: effectiveness of adaptation, side-effects, cost and benefits, conditions for decision-making. In Polish—Norwegian case study, which focus on spatial planning particular interest should be given to the issue of possible flood losses which can arise because of damages or destruction of water control structures, infrastructure, buildings or other structures near the river or to maintain the water control structures in good technical order.
The objectives of the national authorities may need to be scenarios for individual municipalities to implement climate change adaptation measures.
Each simulation scenario should, therefore, provide estimates of indices chosen for the evaluation of adaptation strategy.
In Norway there are 428 municipalities. Spatial planning management of these units is regulated by the legislative Act for Building and Planning (PBA). It is audited by an appropriate regional unit every four years, even though the continuous procedure for the flood adaptation process is needed (Haasnoot et al. 2014) this adaptation cycle is not sufficient on its own. There is also a need to consider the cases which might not be framed in the procedure, because of extraordinary spatial location or difficult administrative status.
In Poland, which is much more densely populated, there is a four-level territorial administration (national, voivodship, districts and municipalities). At present there are 2478 local level territorial units. Spatial planning management of these units is regulated by two separate legislative Acts for Building and Spatial Planning. These legislative regulations are not sufficient to execute the formulation of local plans in each municipality (NIK 2013) and to the best of our knowledge, based on the Art. 400a of Environmental Law (Dz.U.2017.0.519) and contemporary National Budget there are no national funds allocated for municipalities for climate change adaptation. Flood management strategy does not include plan of adaptation actions and adaptation actions are not followed. Lewandowski et al. (2016) highlight that Polish national and regional strategies of flood risk management do not include in practice spatial planning, urban green infrastructure or flood insurance measures despite of official declarations.
Due to the fact that in both Norway and Poland there is a need for knowledge and competence in the municipalities on how to consider floods, including the climate change effect in spatial planning, the chosen adaptation scenario should contain the strong educational and communication compound which will highlight the spatial planning—climate change relation.
This effect can be obtained by prioritizing in the scenario climate change adaptation in the governmental policy, at each level of public administration and finally, securing additional financial resources both at the national and local levels.
Legal regulations instruments in poland and norway (step 4)
The decision of chosen adaptation scenario is half the success, the second half is the feedback from the legislative instruments. In this sub-section the regulations concerning water management which are in force in Poland and Norway are scrutinised. Legislation related to flood adaptation has a different legal basis in Poland and Norway. Poland, as a member of the European Union follows its internal water management legislation the “Floods Directive 2007” (Directive 2007/60/EC). Its provisions are consistent with the “Water Framework Directive 2000”, officially known as Directive 2000/60/EC of the European Parliament. The fact that flood adaptation is carried out in changing climate conditions creates a need to assess all its components every six years (Directive 2007/60/EC) This is also an opportunity for the development of a single, coherent and multifaceted risk management strategy.
Although Norway has considerable large adaptive capacity, climate change is expected to have high costs, both human and material, if it is not taken into account in planning and decision-making (NOU 2010). A relatively new Planning and Building Act (PBA) of 2008 gives more emphasis on helping the municipalities and regional authorities to incorporate climate considerations into their planning. This act grants the legal authority to define areas acting on buffer zones. This implies that spatial regulations may be introduced to land areas exposed to flooding. In the technical guidelines of the PBA different safety classes based on flood recurrence intervals, are set up for different types of buildings and in addition it is stated that climate change has to be taken into account in their spatial plans.
Strategy implementation: cooperation on scenario (step 5)
In the present study, our illustration is based on the structure of water management systems in Poland and Norway presented in Table 1.
The flowchart (Fig. 6) presents relations between units related with flood risk management and with adaptation to floods. Interactions between units, adequate to the needs of units at different levels of cooperation are shown. Cooperation is understood here as “communication-feedback-action” process between units at the same level and between units at different levels. This approach, by its structure, is an integration of top-down and bottom up approaches and it conforms to the IWRM approach.
However, not all interactions between administrative units are carried out. As far as regional-scale flood adaptation policies for Poland are concerned, the strategy is planned by regional governments (Voivodship governments) and is included in the Voivodship development plan. Regional strategies for flood management are the responsibility of Regional Water Management Boards which are controlled by the National Water Management Authority and are defined for water regions rather than voivodships. The water region strategies are introduced and included in development strategies of voivodships together with guidelines for adaptation actions identified for each voivodship. Boundaries of Regional Water Management Boards are not consistent either with administrative nor with catchment boundaries, which complicates water management in the country.
Local Government units are responsible for climate change adaptation actions identified in the adaptation policy for Poland prepared for the period up to 2020 (IOŚ-PIB and KLIMADA 2013) for the local level. The adaptation actions include implementation of local monitoring and prevention systems i.e. the capacity of sewage system, speeding up the reaction time for the hazardous event, revitalization of the green infrastructure, and adaptation of city plans regarding the use of rainfall water. However, those adaptation actions require the legislative regulations related to local spatial planning in future climate which are still missing in Poland.
The Norwegian white paper on climate change adaptation (Climate change adaptation in Norway — Meld. St. 33 2012–2013) states that the Ministry of Climate and Environment, has the overall responsibility to coordinate climate change adaptation. However, the responsibility to assess climate change vulnerability, adaptation needs and to implement adaptation needs in practice is the responsibility of the individual sectors. The administrative flood management structures have three levels: national, regional (county) and local (municipality) (Table 1). However, in practice it is the Norwegian Water Resources and Energy Directorate (NVE) that is responsible for giving advice to the municipalities on how to reduce flood risks both at present and in the future. This means that NVE has the role of both the national and the regional level authority.
In general, municipality plans in Norway are renewed every four years to provide pathways of behavior and knowledge on possible improvements. The municipality is required to check that measures are implemented in compliance with permits and applicable laws and regulations. The municipality may choose to audit all building activities and in compliance with the building application regulations, prepare a strategy for the control work.
The NVE has a responsibility to follow-up the plans regarding river floods and flooding, including climate change adaptation. The PBA gives the municipality the responsibility to protect and secure the population from flood, but they will receive governmental guidance and assistance in this work. For the river basins most prone to flood damages, NVE has produced flood risk maps and checks that the flood risks have been evaluated in the municipalities’ land-use planning.