Gotland – Sweden’s largest island
Gotland is Sweden’s largest Island, located in the Baltic Sea about 100 km from the mainland. Gotland is one of the least populated regions of Sweden. However, the island is a popular summer destination for tourists and therefore the population increases vastly during summer months. The island is originally a coral reef based on limestone and large parts of the island have thin soil layers which limit the volumes of groundwater and the possibility to store water for long periods without rain (summer season). The region is covered by 31% arable land (mainly growing crops for cattle and pastureland) and 40% forest (mainly smaller independent patches).
Tourism and agriculture are important
Tourism (approx. 700,000 visitors/year) and agriculture are the main economic activities in the region, apart from lime and cement mining (which are not included in the case study), and the food industry. Agriculture in Gotland employs around 10% of the workforce (and almost 30% of the workforce including agriculture dependent industries). Most farms in Gotland are small, often maintained by farmers who are mastering multi-tasking skills, although there are some large-scale agricultural facilities, too.
Apart from lamb meat production, grain and vegetable cultivation represent the most important agrarian industries on the island. Gotland’s grain production is dominated by wheat, followed by barley. Compared to other parts of Sweden, there is a clear difference in land use when it comes to pasture. 23% of total agricultural land on Gotland is pasture, compared with 15% for the rest of Sweden. This is due to the large proportion of sheep as well as dairy and beef cows.
Other big economic players on the island are the concrete industry and the limestone quarries that have a big impact on the island. These industries are a complex issue in themselves with several national actors and stakeholders and will not be included in the case study.
Water shortage is a problem
In recent years, Gotland has on several occasions suffered from severe water shortages. The area is probably one of the areas in Sweden with the lowest groundwater levels and is fed with potable water from a desalination plant. As an island, Gotland will suffer from sea level rise that could lead to land loss and groundwater salinisation. The transformation of wetlands and raising the groundwater levels are the two main challenges for the region.
The annual precipitation on the island is approximately 550 mm. However, thin soil layers, extensive drainage, and a lack of coherent reservoirs in the sedimentary limestone bedrock lead to a high precipitation run-off. Furthermore, the peak tourist season is during the summer, resulting in a large seasonal variation in water demand with the highest demand occurring when water supplies are at their lowest. The number of people who live in Gotland permanently is about 58,000, just a fraction of the number of visitor in the summer.
The precipitation is highest during the autumn months, while the biggest outtake of water is during the summer. With the thin soil layers there is nowhere for the ground to retain the water in natural aquifers; the water must therefore be collected, stored, and reused. Due to the past years of drought, there is a rapidly increasing need for irrigation of crops and pasture. The current water shortage for irrigation, which is predicted to become somewhat permanent with climate change, calls for reformation of the land use and efforts from several different private and public bodies.
Unlike other parts of Sweden, the water supply system of Gotland is built on a large proportion of private solutions, with only 67% of the households connected to the public water supply system. Around 65% of the public water supply system relies on groundwater. The remaining 35% of the water comes from lakes and one desalination plant (Sjöstrand et al. 2019).
Because of Gotland’s relatively thin soil layers that have been intensively drained, the island can only retain a small portion of the infiltrating rainwater as groundwater. In addition, the landscape is mostly flat which doesn’t favour water storage. An uneven precipitation over the year makes parts of the island dependent on long distant piping from a centralised water supply, including desalination plants. Recent dry summers, on-going climate change and the increasing water demand due to a growing population and tourism have been a wake-up call.
Potential solutions (LAMS)
The most important potential Land use-based Adaptation and Mitigation Solutions (LAMS) in Gotland are linked with tourism and agriculture, because these are important for the Gotland economy. Both these sectors are highly dependent on water supply which has already started to be a big challenge for the island. These LAMS may directly impact agriculture (e.g. reduced tillage, optimised fertiliser application rate, improved agricultural irrigation efficiency) or have a more indirect effect through behavioural change (a shift in people’s diet, per capita reduction of domestic water use).
Furthermore, many LAMS (e.g., wind power plants and agro-voltaic energy) are also relevant due to the ongoing energy and sustainability projects that have started in Gotland in recent years. The region and its authorities are all arguing for using fresh water in a wiser and more environmentally sustainable way. As such, Gotland is an ideal arena for the development of new policies, methods and technologies to collect, store and reuse water.
One example of this is the on-going development of complementary systems for the water supply for the future, and for the vision of a circular society that has been initiated at the most southern part of the island. Here, the so-called Testbed Storsudret for a sustainable water supply, is developed and managed by Region Gotland and IVL, together with academic partners, NGOs and SMEs.
Stakeholders in Gotland
Stakeholders involved in this case study are represented by the public sector (regional government and municipality), associations (NGOs, and farmers organisations) and the private sector (farmers and households). Several factors affect the region. Climate risks increase year-by-year and intensify problems related to water scarcity and droughts (especially in high tourist seasons). At the same time, the effects of climate change could induce a shift in the destination for several vacationers, impacting the local economy.
