2017-09-13 WATER SAVING CHALLENGE Field Study 5: Vis Figure 1. The Adriatic Sea with Vis in the middle. Photo courtesy of Samantha Cristoforetti/NASA 1 (24) WATER SAVING CHALLENGE Christian Pleijel [email protected] Tel +358-457-342 88 25 FIELD STUDY: VIS Content 1 Summary 2 2 Introduction 3 The assignment The client Study objects The three levels of an island Methodology 3 The water of the island 6 Location Geology Hydrology and climate Vegetation 4 The water of the islanders 8 Human pressure Virtual distance Water consumption 5 The water of the community 14 Governance Water procurement Wastewater Water quality Cost and taxes Future plans 6 Water saving 22 Benchmark #1 Benchmark #2 Benchmark #3 7 References 23 2 (24) WATER SAVING CHALLENGE POGREŠKA! IZVOR REFERENCE NIJE PRONAĐEN. FIELD STUDY: VIS 1 Summary Vis is a Croatian island in the Adriatic Sea, 55 kilometers from the mainland, with an area of 90 km2. 3,460 persons live in the island’s two municipalities. Ten times the population comes to visit every year = 36,750 tourists, spending some 200,000 days on the island. The pressure on the islands' freshwater system (as well as energy distribution, sewage and waste recuperation and treatment, roads, ports, telephones, internet, transports, postal services, healthcare and fire brigade) from tourism is not so high. The water supply system of the island uses its own sources of drinking water from two lo- cations: Korita (drilled wells) and Pizdica (fresh water spring). The pumping station Korita is located in the interior of the island above five drilled wells containing water at depth of approximately 160 meter. Water is pressured into a pumping pool from where it is distrib- uted to consumers (20 l/s). The amount of water needed for the island can be estimated to 139,000 m3 (139 million liters). To manage the water scheme, Vis has a company owned by the two municipalities to- gether, which uses an impressive IT system to guard, calibrate and manage water supply on the island. To save water, there was a household water saving campaign by SUNCE (needs to be de- scribed), there are public announcements and there are limitations in water use for tour- ists (yachts). The island would like to get through this summer season without having to turn off the water supply. There is an interesting idea of engaging school kids in water sav- ing. Vis, May 2017 Christian Pleijel 3 (24) WATER SAVING CHALLENGE FIELD STUDY: VIS 2 Introduction 2.1 The assignment The Vis study is part of an assignment to search for, find, describe and share good exam- ples of water saving practices on eight European islands, islands who do not solve water scarcity just by bringing more water through pipelines, desalination plants and tankers, but are making efforts to save water. The project is looking for best practices within four areas of water saving actions: 1 Training: Information, good examples, schooling, campaigns, understanding that water has different qualities which can be used for different purposes. 2 Engineering: Technologies for reducing water consumption in households (water taps, showerheads, toilet sinks etc), for reducing leakages in mains and pipes, for more effi- cient desalination/reverse osmosis processes, treatment of wastewater etc. 3 Billing: Differentiated pricing of (municipal) water that lead to water saving. 4 Cutting: Switching off the (municipal) water: mostly for shorter periods of time. Obstacles to save water can be found in governance (water saving is not a political issue), regulations, cost, taxes and financial obstacles (the water company does not earn money by saving water), no ‘sense of urgency’, sustainability indicators are underdeveloped or inexistent, management (saving is not an objective), human behaviour, business threats (water saving might ruin the visitors’ experiences and damage the island’s brand), tech- nology and over-capacity (the island has a system which procures more water than the is- land needs, even in peaks). 2.2 The client The assignment has been given to the Royal Institute of Technology (KTH) in Stockholm by MEP Tonino Picula from Croatia, the Hellenic Small Islands Network, l'Association des îles du Ponant, the Irish Islands Federation/Comhdháil Oileáin na hÉireann and ESIN – the European Small Islands Federation. 2.3 Study objects Eight islands are included in the project: Tilos and Ithaka in Greece, Lastovo and Vis in Croatia, Sein and Houat in France, Inisheer and Cape Clear in Ireland. They have been cho- sen because they (a) all have a scarcity of freshwater, (b) represent different sizes, seas, hydrogeology, climate, size of population and remoteness, (c) have what seems to be inter- esting solutions for saving water, and (d) have been in previous contact with us which makes it easy to obtain true data within a limited time and budget. 4 (24) WATER SAVING CHALLENGE POGREŠKA! IZVOR REFERENCE NIJE PRONAĐEN. FIELD STUDY: VIS Figure 2. The eight islands in the study 2.4 The three levels of an island The freshwater system of an island can be described as three interlinked levels: a The water of the island This is the basic geophysical system level which encompasses the physical geographical conditions on the islands no matter if people live there or not: geology, oceans, skies, hy- drology, meteorology, flora and fauna. This is the physical landscape. b The water of the islanders At the next level, humans move in and make their human footprints: they build houses and villages, till the soil and water, eat, drink, walk, arrange their social life with children, schools, elderly care, health care and security. This is the cultural landscape. c The water of the community At the top level, the humans build a common infrastructure of roads, water, sewer, tele- phone, broadband, fossil and renewable energy sources, ports and ships. Water is pro- duced, distributed, managed, financed and administrated; This is the technical landscape. 5 (24) WATER SAVING CHALLENGE FIELD STUDY: VIS 2.5 Methodology Data about the islands has been collected through desktop research and field studies, dur- ing which we made make semi-structured interviews with politicians, technicians and citi- zens, investigated technical installations, took part of documents, plans, studies, maps and earlier research. This field study on Vis was undertaken by Christian Pleijel and Ivan Matic on the 28th, 29th and 30th of May, 2017, under supervision of professor Anders Nordström from the Univer- ity of Stockholm and professor Sara Borgström at KTH. We are most thankful to the water manager Slaven Kevo and the mayor of Komiza Tonka Ivcevic for their time and efforts to answer our questions and guide us around the island. Figure 3. Ivan Matic Figure 4. Slaven Kevo Figure 5. Tonka Ivčević 6 (24) WATER SAVING CHALLENGE POGREŠKA! IZVOR REFERENCE NIJE PRONAĐEN. FIELD STUDY: VIS 3 The water of the island 3.1 Location Vis is a Croatian island located in the Adriatic Sea 55 km from the mainland. The surface of the island is 90 km2. It is surrounded by numerous smaller islands: Biševo, Budikovac, Brusnik, Jabuka, Ravnik and Svetac. Figure 6. Vis and its neighbouring islands 3.2 Geology Three hill chains and two valleys containing several smaller karst fields are well distinguished. The highest point of the island is Hum 587 m abobe sea level. Rock composition: cretaceous limestone and dolomite; Triassic and clastic rocks. 7 (24) WATER SAVING CHALLENGE FIELD STUDY: VIS Figure 7. Schematic hydrogeological map of Vis1 Figure 8. Schematic hydrogeological map of Vis2, section A – B. Note how low the groundwater surface is. Not far above sea level, which means great difficulty in getting fresh water from the wells. 1 Kapelj, Terzij, Kapelj and Dolij: Recent hydrogeologic study of the Vis island (2002) 2 Kapelj, Terzij, Kapelj and Dolij: Recent hydrogeologic study of the Vis island (2002) 8 (24) WATER SAVING CHALLENGE POGREŠKA! IZVOR REFERENCE NIJE PRONAĐEN. FIELD STUDY: VIS The groundwater formation is estimated at approximately 400 mm and takes place almost completely during the winter. The groundwater flows quickly into the limestone that dom- inates the island's bedrock. Figure 8 clearly shows that the groundwater surface is very close to the sea level, which is not usually normal in, for example, granite bedrock. This indicates big problems in getting freshwater from the island's groundwater. 3.3 Hydrology and climate Vis has a Mediterranean climate with long and hot summers. The yearly sunny hours are above 2,600 hours, the average summer humidity is 64% and the average yearly tempera- ture is 160C. Very high medium air temperature in August (260C) and droughts during sev- eral months. Years without rain for 3-4 months are not rare. The winters are soft (medium air temperature in January is 100C). The average yearly rainfall of 800 mm (not confirmed). There are no surface waterflows except after heavy rainfall (typical for Adriatic islands). 3.4 Vegetation Mediterranean evergreen vegetation of low bush type is dominant. Olives, lemon, manda- rin and vines are cultivated. Figure 9. View of Komiza 9 (24) WATER SAVING CHALLENGE FIELD STUDY: VIS 4 The water of the islanders There are two villages on Vis: Vis and Komiza, located on each end of the island. The dis- tance between the villages by the old road which passes south of the island is 20 km over the pass Sveti Mihovil. During Austro-Hungary times, the island had three times more inhabitants than today. There are numerous causes of such demographic decline: the first disease of the vines, the First World War (which led numerous Komižaans to emigrate to America), the Second World War, the harsh military isolation of the island, coupled with the associated eco- nomic downturn, led to a large outflow of young people who went looking for a job.