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
Tel +358-457-342 88 25
FIELD STUDY: VIS
Content
- 1
- Summary
- 2
- 3
- 2
- Introduction
The assignment The client Study objects The three levels of an island Methodology
- 3
- The water of the island
Location
6
Geology Hydrology and climate Vegetation
4
5
The water of the islanders Human pressure Virtual distance Water consumption The water of the community Governance
8
14
Water procurement Wastewater Water quality Cost and taxes Future plans
6
7
- Water saving
- 22
23
Benchmark #1 Benchmark #2 Benchmark #3 References
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 locations: 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 distributed 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 together, 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 described), there are public announcements and there are limitations in water use for tourists (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 saving.
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 examples 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 efficient 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 island 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 chosen 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 interesting 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, hydrology, 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, telephone, broadband, fossil and renewable energy sources, ports and ships. Water is produced, 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, during which we made make semi-structured interviews with politicians, technicians and citizens, 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 dominates 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 temperature is 160C. Very high medium air temperature in August (260C) and droughts during several 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, mandarin 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 distance 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 economic downturn, led to a large outflow of young people who went looking for a job.
In the 19th century and the first half of the 20th century there were well developed fisheries and a fish processing industry mostly in Komiza (seven factories), while Vis and the villages in the interior of the island were more oriented to viticulture.
Figure 10. Komiža’s fish processing factory
closed down in 2012 after years of struggle
In socialist Yugoslavia, for the sake of its strategic position, Vis was closed to foreigners (the ban on the arrival of aliens was abolished only in 1989) and it was completely converted into a great military fort. More than 30 military facilities were located here, including an underground military hospital and a naval shelter tunnel. The consequence of the half-century isolation was an economic downturn and inability of tourism development, associated with a massive emigration of the population.
After the independence of Croatia and the departure of the army from the island (on 30 May 1992, almost six months after Croatia's international recognition), migration stopped and tourism development began. In the 1990’s, the municipalities of Vis and Komiza were rebuilt and received the status of cities in 1997.
Today the economy of the island is directed towards forestry and fisheries (22%), services for accommodation and food service (20%), wholesale and retail trade, repair of motor vehicles and motorcycles, manufacturing (5%) and administrative services (2%).
10 (24)
WATER SAVING CHALLENGE
POGREŠKA! IZVOR REFERENCE NIJE PRONAĐEN.
FIELD STUDY: VIS
- 4.1
- Human pressure
Today, Vis has a lucrative nautical tourism sustained by two large anchorages in Komiža and Vis. There are 4 hotels, several thousand beds in private accommodation and one undeclared camp.
Vis and Komiza have 3,460 permanent residents together (2011), 36,750 tourist arrivals and 213,894 overnight stays (2015), most from June to October.
The human pressure on the islands' infrastructure including freshwater, energy distribution, sewage and waste recuperation and treatment, roads, ports, telephones, internet, transports, postal services, healthcare and fire brigade, can be calculated as follows:
Residents Visitors
365 days
5-6 days
3,460 1,262,900 man-days
- 36,750
- 213,894 man-days
- 1,476,794 man-days
- Sum of man-days
Table 1: Human pressure on Vis
The human pressure on the island is thus about 1,5 million man-days. If divided by 365 days, it is equivalent to a resident population of 4,046 inhabitants.
The pressure from humans is very uneven, peaking in the four summer months when water is most scarce, the population rises approximately 2.8 times. A hot day in August, 6,000 visitors plus 3,500 residents are on the island = 9,500 p/90 km2 = 108 p/km2.
- 4.2
- Remoteness
Vis is situated 55 kilometres from the mainland. It is connected by ferry line Split-Vis-Split. In addition to the ferry line there is also a fast-shipping line that connects the island of Vis once a week with Split and Hvar.
Through the town of Komiža passes the state road DC 117 Komiža-Podhumlje-Vis. State Road D117 is a total of 19.9 kilometers long. It connects Komiža with Podhumlje, Podšpilje, Dračevo, Plisko Polje and Vis. The city passes along the county road ŽC 6212
Komiža-Vis overall length of 9.9 kilometers. From the local roads in the city area there is LC 67216 Women Head linking to state road D117.
There is a bus line Vis-Komiža-Vis.
The town of Komiza is also connected to the island Biševo, which is 5 nautical miles from Komiža.
The air traffic is directed at the Split airport, and the railway to the Split railway station.
11 (24)
WATER SAVING CHALLENGE
FIELD STUDY: VIS
- 4.3
- Water requirement
CONSUMER’S PERSPECTIVE
In Europe, the average daily water consumption rate per capita varies between 40 and 150 litres per day. In Croatia, it is 120 liters / person and day according to Eurostat3, whereof 8 litres for food and drinking, 48 litres for bath and shower, 20 litres for dishes, 12 litres for washing, 8 litres for other purposes and 26 litres for flushing the toilet.
The darker the colour of the water in the diagram, the less purified does it need to be. It is perfectly sound to flush your toilets with rainwater (dark blue) but many people buy bottled water to drink (light blue).
From earlier studies of small island water consumption4, it is reasonable to assume that resident islanders use 75% of the national average 120 litres/day = 90 l/d and tourists the Croatian average = 120 l/d.
Based on the calculation in table 1, the yearly water consumption on Vis can be estimated to 51 million litres:
- Category
- Man-days Consumption
litres/day
Total consumption
Residents (365 days) Visitors
- 3,460
- 90
120
133,661 m3
25,667 m3
139,328 m3
36,750
Total water consumption
Table 2: Calculated yearly water use on Vis
Given the average water consumption of Croatian people (120 litres according to Eurostat5), the island would need 139 million litres (139,238 m3) of freshwater per year.
Of this, 10 million litres are used for drinking and cooking, 56 million litres for showering and bathing, and 28 million litres for flushing toilets.
3 http://ec.europa.eu/eurostat/statistics-explained/index.php/File:
Total_freshwater_abstraction_by_public_water_supply,_2013_(m³_per_inhabitant)_YB16.png
4
http://www.stromstad.se/byggaboochmiljo/vattenochavlopp/vakosteroarna.4.fc6ae6c153c5fdf8ad127e2.html
5 Geology of the Ionian Islands, Higgins & Higgins (1996)
12 (24)
WATER SAVING CHALLENGE
POGREŠKA! IZVOR REFERENCE NIJE PRONAĐEN.
FIELD STUDY: VIS
PRODUCER’S PERSPECTIVE
Figure 11: Water production 2016
Figure 11 shows the islands total water production in 2016, peaking early August and distinct low water consumption July 14-19 when it was raining with no people bathing, no showering at beaches and hotels.
The consumption of water per capita for household purposes in the previous year was 67 m3, for industry purposes 26 m3.
13 (24)
WATER SAVING CHALLENGE
FIELD STUDY: VIS
- 5
- The water of the community
- 5.1
- Governance
Croatia has 452 municipalities (they were 200 in former Yugoslavia) with Vis island and its two self-governed municipalities Vis and Komiža belonging to the Split-Dalmatia County. Taxation is solely managed by the state and partly reversed to the municipalities.
The two municipalities have a joint owned water management company based in Korita on the municipality border. In Croatia, water management is entirely under municipal jurisdiction while building permits are issued by the County.
Figure 12: Municipalities in Split-Dalmatia county. Observe the size of Vis and Komiza, when the sea is included
14 (24)
WATER SAVING CHALLENGE
POGREŠKA! IZVOR REFERENCE NIJE PRONAĐEN.
FIELD STUDY: VIS
Both Vis and Komiza have recently passed Strategic Development Plans for the period 2015-2020.
It is the opinion of Komiza mayor Tonka Ivčević that the island shuld have a joint strategic plan with a common structure6.
The two municipalities do not want to merge for identity reasons, although it is said to give huge savings. Well-functioning cooperation such as water management could be extended to other areas.
In 2009, the municipalities service/infrastructure company was restructured and water management was made into a separate company “Vodovod Otoka Visa-Komiza”. Leakages were 70%, constant interruptions, no one knew how many water meters were installed, bad billing system, the clients were not paying – big challenges!
Water investments have been 280 million kuna (~38 million euro) from 2011 to 2017, funded by Croatian Water by 80 percent, and by 10 percent from the two municipalities respectively.
- 5.2
- Energy
In winter time the water system is only pumping at night, when electricity is cheap. Water reservoirs are run on photovoltaic and wind energy.
Figure 13: Water reservoir with solar panels and wind turbine
6 Interview with Tonka Ivčević May 30, 2017