At the European Union level, there is a strong policy coherence between water policies and those on land, agriculture, energy and climate. More advantage could be taken of synergies between these policies in implementation on national, regional and local levels. Coherence between these policies, therefore, needs more attention, during their planning and implementation
Policy coherence results from systematic efforts to reduce conflict and promote synergies within and between individual policy areas. Synergy is achieved when the combined efforts of two or more policies accomplish more than the sum of the separate results from each policy. Policies, thus, reinforce each other. Conflict arises when the goals and instruments of one policy impede those of another. When conflicts arise, choices should be made about the related trade-offs.
The SIM4NEXUS project mapped and analysed the policy coherence between the current European, national and regional policies on water, land, agriculture and food, energy and climate, in nine case studies. Water objectives are predominantly synergistic with the objectives for the other sectors, as they support the sustainable use of resources, economic activities, climate change resilience and the provision of ecosystem services. The other way around, numerous policies for the other sectors positively influence the water objectives. However, some policies in the nexus may negatively affect water objectives. For example, the production of biofuel crops may cause water pollution and scarcity, hydropower may impede a good ecological status of rivers, economic policy for the agricultural sector may negatively affect water objectives if environmental standards are not met. In these cases, progress in achieving energy, agriculture and climate objectives comes at the expense of water objectives. These conflicts are not always mentioned in policy documents at EU or national level, but emerge during implementation.
Common interests and shared goals are important enabling factors to develop arrangements for cross‐sectoral coordination and cooperation and assess and reach policy coherence. Reaching an understanding and agreement on shared interests and goals is time-consuming and requires a great deal of manpower and funding, which, however, pays off in terms of avoided deadlocks and conflicts in the implementation of policies.