Adaptation: Field of Action Spatial, Regional and Urban Development Planning

Bird's eye view of geometrical arranged, colourful fields and settlementsClick to enlarge
Climate change also affects spatial and land use planning.
Source: Lukas Pollmüller/photocase.com

Due to the cross-cutting nature of spatial planning, it can take the consequences of climate change into account across sectors. Spatial planning must reconcile or weigh up different demands and place spatial precautionary concepts at the beginning of risk prevention chains.

Importance of spatial, regional and urban land use planning for climate adaptation

Spatial planning has an important role to play in climate adaptation. Due to the very different sectoral climate impacts with their interactions as well as their spatial diversity, which continues down to the local level, there is a need for interdisciplinary and inter-area coordination in the assessment of spatially relevant risks and opportunities as well as the identification of possible adaptation measures. In this respect, spatial planning in Germany has an established planning system in which overall planning and sectoral planning can work together.

Climate adaptation is anchored at the federal level in the German Spatial Planning Act and in the guiding principles of spatial planning. The concrete planning consideration of the requirements of climate adaptation takes place regionally and communally at the level of land and regional planning or urban land use planning. At these different planning levels, as well as in the context of close coordination with the respective spatially relevant sectoral planning (e.g. water management, landscape planning, nature conservation, transport), spatial planning has numerous opportunities to influence adaptation to climate change.

Indicator from the DAS monitoring: Land used for human settlements and transport infrastructure

Contributions of regional planning to climate adaptation

Regional planning, as a link between different levels, (specialised) departments and public and private actors, is suitable for developing and implementing regional action strategies for climate adaptation. In this way, it can concretise federal and state requirements in a region-specific and cross-sectoral manner and bring them together with the interests of the municipalities. In principle, regional planning contributes to climate adaptation by determination (e.g. designation, clearance, securing) areas for uses that reduce climate risks and damage potential. Relevant fields of action for climate adaptation in regional planning are considered in many regions: Preventive flood protection in river basins, reduction of hazards in coastal regions, protection against heat and heavy precipitation in settlement areas, conservation and protection of water resources and preservation of biological diversity.

Flood protection: Large-scale retention areas can be secured for flood hazards (e. g. through dyke relocations). For this purpose, regional planning can define priority areas for preventive flood protection in which flood protection has priority and must be observed as a binding requirement. Other spatially significant uses (e. g. housing development, commercial development) that are not compatible with the objective of flood protection are excluded or can be subject to restrictions on use. When defining a reserved area, flood protection has a special weight in the balancing of competing interests. It does not completely exclude the admission of conflicting uses such as residential development if the construction method is adapted to the existing flood hazard (e. g. stilted construction, "floating houses").

Indicators from the DAS monitoring: Priority and restricted areas for (preventive) flood control | Settlement use in flood-risk areas – case study

Coastal protection: Coastal protection endeavors to adapt the technical protection facilities (e. g. dikes) along the coast to sea-level rise and rising storm surge levels in terms of construction and technology. Regional planning can support coastal protection in this respect by defining the areas required for the upgrading of dikes to prevent changes in use. Furthermore, it can secure the sand and clover extraction sites necessary for dike construction. In order to reduce the potential for damage in coastal regions, regional planning can designate safety areas along coastal sections that are threatened by erosion. With regard to building development, specifications can be formulated for areas protected from storm surges as well as for areas not protected.

Protection against heat stress in urban regions: The protection and designation of climate-active open spaces such as cold-air production areas (e. g. meadows, farms) and fresh-air production areas (e. g. forests) as well as cold-air and fresh-air corridors in densely populated areas by regional planning contribute to ensuring sufficient ventilation of the settlement structure and to minimise or completely avoid climatic stresses for the population in urban regions. Accordingly, cold and fresh air production areas are to be kept free of settlement. Crosswise large buildings, dense plantings as well as afforestation or fillings, which impair the transport of cold air, should be excluded by specifications on the respective areas.

Indicator from the DAS monitoring: Priority and restricted areas for special climate functions

Protection of water resources: With regard to the conservation and protection of water resources, spatial planning can support water resource management. To this end, land and regional planning can define priority and reserved areas for drinking water and groundwater protection in order to secure water resources in planning terms. This concerns both the protection and conservation of groundwater resources and the use of groundwater. Specifications for controlling water consumption can exclude water-intensive uses (e. g. commerce, industry, settlements) in areas that are particularly affected by drought. In the future, another task of spatial planning could be to secure suitable areas for precautionary measures against water scarcity by means of priority or reserved areas, and to reserve these areas in the long term, which (could) be needed for the following measures, among others: the expansion or new reservoirs for (drinking) water supply or the construction of polders and rainwater retention basins for the temporary storage of water surpluses for delayed use as industrial water, for agricultural irrigation or for the renaturation and rewetting of bogs and floodplains.

Indicator from the DAS monitoring: Priority and reserved areas for groundwater / drinking water

Protection of biodiversity: By designating priority and reserved areas for nature and landscape, regional planning can contribute to the establishment of an ecological network (biotope network). In this way, it can secure or impose restrictions on the use of areas that are important for the adaptation of animal and plant species to climatically induced changes, e. g. the climate change-induced migration of species due to range shifts. As a supplement, regional green corridors can be secured as priority areas.

Indicator from the DAS monitoring: Priority and reserved areas for nature and landscape

green landscape
Regional planning can designate priority and reserved areas for climate adaptation measures.
Source: Peter H / Pixabay

Contributions of urban land use planning to climate adaptation

Within the framework of urban land use planning spatial planning can also contribute to reduce the sensitivity of settlement structures to climate change at the municipal level. Urban land use planning is organised in a two-stage planning procedure; a distinction is made between preparatory urban land use planning (land use plans) and binding urban land use planning (development plans). Urban land use planning derives its scope of action from the German Federal Building Code (BauGB). With the amendments to the Building Code (BauGB) in 2011 and 2013, the federal government has given climate adaptation a higher priority by giving it additional legal weight in the consideration of planning law. The amendment in 2013 also laid the legal foundations to ensure that climate adaptation goals are also taken into account in urban redevelopment and rehabilitation measures. Contributions of urban land use planning to climate adaptation come in particular from the possibilities of representation and specification in land use and development plans.

The following starting points are presented in the areas of action: flood protection, coastal protection, protection of settlement areas from extreme weather events, protection of water resources and precautionary measures for biodiversity and nature conservation.

Flood protection: Flood protection concerns are anchored in the BauGB as a planning guideline to be observed when drawing up urban land use plans. Areas necessary for flood protection, the construction or expansion of flood protection facilities, and water runoff can be shown or specified in the land use or development plan. The designation of new building areas in flood plains established under water law is only permissible under strict conditions.

Coastal protection: In view of rising sea levels and an increased risk of flooding, consideration of coastal protection requirements in urban land use planning is particularly important in settlement areas with limited spatial conditions. Within the framework of urban land-use planning, land-use and development plans can show or determine separate areas for flood protection and flood protection facilities in order to secure the necessary areas for the widening or relocation of dykes. In addition, restrictions on use and development can be formulated for low-lying areas behind dykes in order to reduce the potential for damage and to concentrate residential development in areas that are less at risk.

Protection of settlement areas against extreme weather events: In order to adjust the settlement and open space structures, land use planning can make representations or specifications in land use or development plans or in local building regulations and statutes in order to counter increased heating of densely populated settlement areas and the resulting heat stress on people as well as heavy rain events and the associated risk of flooding.

Protection against heat stress: With regard to the issue of heat, there are opportunities in particular to implement measures to protect green and open spaces that are important for the settlement climate and to ensure sufficient ventilation of the settlement structure. Keeping areas that are important for the urban climate free can be ensured through appropriate land-use designations and specifications in urban land-use plans (e. g. as green spaces). Ensuring better ventilation of an area can be achieved in the development plan by specifying the minimum size of building plots, the height of buildings and the orientation of buildings. There are also possibilities in urban land use planning to implement measures for the greening and shading of traffic areas and properties to improve the microclimate by specifying plantings in development plan areas. Furthermore, it is possible to stipulate green roofs and façades in the development plan in order to reduce urban climate deficits.

Protection against heavy rainfall: With regard to the issue of heavy rainfall, measures can be taken up in land use plans that primarily serve to secure and reclaim communal retention areas, reduce the degree of sealing in settlement areas and protect buildings and infrastructure from the negative effects of heavy rainfall events. Specific measures for water-sensitive urban development can be stipulated in development plans. These include, for example, restrictions on soil sealing and unsealing measures, near-natural rainwater management (e. g. surface infiltration in troughs, infiltration trenches and cisterns), determination of green roofs and water-permeable surfaces for rainwater retention, determination of emergency waterways and specification of multifunctional land uses (e. g. green spaces with retention function). Flood-adapted construction methods can be ensured in endangered areas through urban land use planning, for example through a stilted construction method, minimum heights of (ground floor) floors, use of water-resistant materials or specifications for backwater systems in sewer networks.
Protection of water resources: Urban land use planning can support climate change-adapted water management and the protection of water resources, in particular through decentralised rainwater management measures and by reducing the degree of sealing in settlement areas. Both can contribute to the local infiltration of precipitation water and to groundwater recharge.

Protection of biodiversity: Biodiversity is an environmental issue to be taken into account in the preparation of urban land use plans. The integration of its concerns can be achieved in the land use plan in particular through the representation of open and green spaces (e. g. parks, allotments, cemeteries) for the protection, maintenance and development of soil, nature and landscape. Their designation lays the foundation for urban biotope networking. By linking regional green corridors with inner-city green areas, urban land use planning can enable animal and plant species to move to climatically more suitable areas if habitats are endangered as a result of climate change. In addition, there are control options within the framework of development plans by specifying permissible plant species for new and compensatory plantings, which can be considered a measure against the spread of invasive species. This also applies to the selection of climate-adapted plant species.

Further measures

Improving the data basis and guiding principles: In order to adapt land use to the changing climate, the data and knowledge basis for planning must be improved. The vulnerability of individual areas must be identified in a targeted manner and, based on this, guiding principles and requirements for climate-adapted spatial structures and development must be developed.

Designing an open and participation-oriented adaptation process: In an adaptation process, open communication about climate change, climate impacts and adaptation strategies and measures is a central task. To this end, various actors from politics, administration and civil society must be involved. This is particularly important when climate change-related adaptation needs are accompanied by land use conflicts. Timely involvement of the actors enables their respective interests to be taken into account at an early stage. In addition, a broad range of expertise and experience can be utilised and the acceptance of the results developed can be increased as well as their implementation promoted. Due to its cross-sectoral perspective, spatial planning is fundamentally suited to take on the task of the "promoter" of a spatial adaptation process. As a cross-sectoral actor, it has the necessary prerequisites to activate networks, to stimulate, coordinate and moderate the cooperation of different actors and to act as a mediator between different interests.

Flexibility of plans: Decisions on climate adaptation planning have to be made under high uncertainty and long-term foresight. Therefore, planning is needed that is able to react flexible to changing circumstances. A comprehensive plan with definitive statements should therefore not be drawn up from the outset, but rather a chain of successive strategic decisions should be made, each offering differentiated solutions at its level. A static allocation of spatial functions should therefore increasingly be replaced by dynamic spatial development with reversible spatial functions. To ensure this, a time limit on spatial uses would be necessary. One possibility would be to apply interim uses, i. e. uses of space that are only permitted for a limited period of time. Another instrument to increase flexibility could be target agreements that specify the result to be aimed for, but not the way to achieve it.