Vulnerability of Water Resources

Summary

Water is a critical natural resource. It is used for drinking water, agriculture, wetlands services, and the production of hydroelectric energy, amongst others. Croatian fresh-water resources are abundant - indeed they are among the richest in Europe. Therefore, water resources are not considered a limiting factor for development in Croatia.
However, while there is no shortage of water per se for use in Croatia, problems do exist.
- First, a large amount of pumped water is wasted, which leads to lost revenue of up to EUR 286 million (0.9% of GDP) per year and increased GHG emissions resulting from the additional use of electricity for pumping.
- Second, farmers often face water shortages at certain critical times of the year’s growing season and, in general, the soil lacks moisture.
Croatia uses a small fraction of the water resources available (about 1%). However, climate change may stress some of the systems that depend upon freshwater. This may be especially important in terms of wetlands services and hydroelectric generation. Wetlands services include nutrient and pollutant removal from water, providing habitat for biodiversity, providing timber and providing hunting areas.
During 2000-2007, 50% of all Croatian electricity production was from hydropower. The Croatian energy sector is potentially vulnerable if climate change results in reduced river flows – which is likely given the predictions of climate models simulating a drier Croatia. Reductions in hydroelectric generating capacity would thus reduce the nation’s level of energy security. For example, in 2003 and 2007, droughts caused significant losses in production compared to the average. This resulted in increased costs for electricity production of perhaps EUR 39-46 million in 2003 and EUR 102-120 million in 2007. Future decreases in hydroelectric production due to reduced runoff and river flows may require lost production to be offset by domestic or imported electricity. Both of these options are more costly than hydropower. It is important to note that increases in costs for electricity production would have multiplier effects throughout the economy.
Climate change is likely to have impacts on the water cycle in Croatia. This could include more droughts, which will affect agriculture and natural environments – especially wetlands. It could also result in decreased river flows, and perhaps even lower levels of ground water, which is used for drinking. Flood severity and drinking water quality/ quantity may also be affected by climate change, though more research is necessary to investigate these possibilities.
Wetlands are particularly important component of water regime in Croatia. They provide a variety of ecosystem services: fishing, forest management, grassland farming, recreation, flood protection, carbon storage and regional climatic stabilization, water regime regulation and habitat for a number of plant and animal species, etc. Aquatic and wetland habitats providing important ecological services are particularly vulnerable to changes in the quantity and distribution of precipitation. Climate change is most likely to negatively affect these services.
Ecosystem services, while ubiquitous, are very hard to value without undertaking original research. In particular, it is difficult to measure the economic value of biodiversity – which is an important aspect of Croatia’s environment. One ecosystem service – nutrient removal – can give us some idea about the magnitude of the economic importance of wetlands. This service involves wetlands and floodplain areas assimilating pollutants (for example Nitrates and Phosphates) and rendering them relatively harmless to the environment. The value of this service can be determined either by analysing the type of pollutant damage avoided, or the costs saved by not having to remove these pollutants by waste treatment. Using the results from a WWF study (1999) the average value of the nutrient removal service (i.e. waste assimilation) of the floodplain and wetlands area of the Danube basin is EUR 250 per hectare per year. Using this estimate, the annual value of the nutrient removal service of 391,000 hectares of wetland habitats in Croatia would be EUR 98 million (1999 EUR value).
The value of other ecosystem services – and possibly the damages caused to them by climate change– could also be substantial. These other services include timber production, hunting land and grassland production. These three services total approximately EUR 1,000 per hectare per year (though this amount still does not include all ecosystem services, such as landscape values, GHG mitigation, fishing, etc.). Depending on the scenario of sustainable land use, the payment that society should provide for the ecosystem services of the Lonjsko Polje Nature Park wetlands was estimated at EUR 20-600 per hectare per year. Assuming that the value of these three services is about EUR 1,000 per hectare, per year for all Croatian wetlands, the value of these services at the national level would be EUR 391 million. Adding the previous value of EUR 98 million for nutrients removal, the total value of the combined ecosystem service would be about 2.36% of the average annual GDP in the period 2001-2005 (EUR 488 million).