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Geographic information systems in mountain risk and disaster management
Applied Geography 63 (2015) 212e219
Contents lists available at ScienceDirect
Applied Geography journal homepage: www.elsevier.com/locate/apgeog
Geographic information systems in mountain risk and disaster management Ehrenfried Lepuschitz Scientific Staff Member of the Institute of Mountain, Risk Engineering at the University of Natural Resources and Life Sciences, Vienna, Austria
a r t i c l e i n f o
a b s t r a c t
Article history: Received 23 March 2015 Received in revised form 26 June 2015 Accepted 26 June 2015 Available online xxx
Mountain risk and disaster management (MRDM) and natural hazards are in alpine countries a national task. Natural hazards in alpine spaces are represented by floods, avalanches, landslides, rock falls and debris flows. MRDM is a very complex system which includes many technical and administrative components. MRDM is based on legal acts and regulations enforced by different federal political levels and departments. A big desire of all involved participants in MRDM is to get simple solutions in this complexity. Austrian Service for Torrent and Avalanche Control has to keep a TAC. With the support of geographic information systems (GIS) it was possible to create a digital TAC. The digital TAC is diverted into different modules: torrent areas, avalanche areas, hazard zone maps, etc. Each module has its own character, but act also interactive. In view of data security TAC has no public access. For public information supply objects can be exported from digital TAC. Only when technical and legal work of an object is correct it can be send through a data tunnel to WebGIS portals with permanent public access for further public use. This paper gives a basic insight into digital TAC supported by GIS which is used in the offices of Austrian Service for Torrent and Avalanche Control. © 2015 Elsevier Ltd. All rights reserved.
Keywords: Mountain risk and disaster management Natural hazards Torrent and avalanche cadaster Hazard zones Geographic information system Digitizing
1. Introduction The risk resulting from natural hazards can be derived from the combination of parameters of physical processes and the damage potential (Keiler, 2004). The damage potential or vulnerability is also influenced by the development of the society. The alpine society has undergone enormous socio-economic changes; the shift from an agricultural society to a modern service industry and leisure oriented society is reflected by an increasing usage of the Alps as an area of settlement, economic activities and leisure (B€ atzing, 1993). The quality of the buildings and their equipment has increased significantly, mainly in order to meet the demands of the tourism industry, reinsurance companies have been pointing out the worldwide trend of increasing damage sums caused by natural hazards. Even though the damage potential has been taken into account more frequently (Keiler, 2004). Controlling natural hazards is a national task of paramount importance to ensure maximum safety, through sustainable strategies in the integrated risk management of natural hazards in mountainous watersheds (Turconi, Nigrelli, & Conte, 2014).
E-mail addresses: [email protected], [email protected]. http://dx.doi.org/10.1016/j.apgeog.2015.06.014 0143-6228/© 2015 Elsevier Ltd. All rights reserved.
Mountain risk and disaster management (MRDM) works mainly with natural hazards in alpine regions comprising flooding, avalanches, landslides, rock falls and debris flows. In the mountains torrents and avalanches become strengthened in catchment areas and cause hazards which threaten urban areas with flooding and avalanche impacts (Graphical Abstract, Fig. 1). Fig. 2 describes a comprehensive circle of disaster, risk and crisis management (FAO, 2004). One half reflects crisis management after disaster and the second half shows risk management before next disaster. The head of the crisis management is mostly the municipal council supported by firefighters and if necessary by volunteers and army. The period of mitigation and prevention pursues the aim to reduce the risk of damage by disaster. It comprises analysis of past disaster, creation of concepts by research and development, project planning and realization, identification of vulnerability with the help of hazard zone maps and financial planning. 2. Austrian approach to MRDM In Austria MRDM is based on federal law, regulations and ordinances. Austria is politically divided into federal provinces and municipalities. Each federal political level has its own legal acts and
E. Lepuschitz / Applied Geography 63 (2015) 212e219
Fig. 1. Torrents and avalanches become strengthened in catchment areas and cause hazards which threaten urban areas, Graphical Abstract.
Fig. 2. Disaster, risk and crisis management circle; crisis management happens after disaster, risk management before next disaster (FAO, 2004).
regulations which are equally applied and complement each other (Table 1). Based on these regulations, Austrian Ministry for Agriculture, Forestry, Environment and Water Management is in charge of strategic steering in MRDM. In Austrian water bodies exists a separation in torrents and rivers. This has mainly a historical reason but which is still existing. On the one hand, in the federal Water Act, legislated in 1959 and adapted to the European Water Framework Directive (Directive 2000/60/EC), the administration for river management is delegated to the federal provinces. Each Austrian federal province has own Technical Water Engineering and Water Management Offices. On the other hand, in 1884, when Austria was still part of the AustrianeHungarian monarchy Austrian Service for Torrent and Avalanche Control was founded by a torrent regulation law to act against natural hazards caused by torrents. The main mission was to plan, develop and finance constructions. Today torrents are together with avalanches regulated by the federal Forest Act, legislated in 1975. Hence, Austrian Service for Torrent and Avalanche Control and Technical Water Engineering and Water Management Offices of the Provincial Governments administrate together with municipalities MRDM.
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Technical terms are defined and described by Austrian federal Forest Act of 1975. A torrent is a permanent or temporary water body which takes and carries dangerous amounts of sediments from the catchment area and its river bed with a strong rise in the water level within a short period of time and stores these sediments inside or outside the river bed or in another water body € (Republik Osterreich, 1975). This characteristic can happen only in mountainous regions, therefore torrents exist only there. Lowlands are mostly free of torrents (see Figs. 2 and 3 in Lepuschitz, submitted for publication). An avalanche consists of huge snow masses which causes hazardous situations and damage because of its kinetic energy or air pressure gained from steep slopes and trenches (Republik € Osterreich, 1975). For better administration the Forest Act defined in Austria the first time that Austrian Service for Torrent and Avalanche Control had to keep a torrent and avalanche cadaster (TAC, Republik € Osterreich, 1975). Already in the 80's and beginning 90's a research group started the realization of a TAC but first only in an analog way. Another field of work is to develop hazard zone maps for each village which is affected by torrents or avalanches. Each torrent and avalanche has a catchment area which causes red and yellow hazard zones in settlements. Other hazard zones which are caused by rock fall, erosion or landslips are shown as brown hazard zones. Furthermore, it's possible to include other colored hazard zones for future measures. Future measures can be active or passive. Active measures are e.g. retention basins in torrents (blue zones) and passive measures are e.g. natural areas where shape and quality of the soil shall not be changed (violet zones). The areas of hazard € zones are to be held free from other buildings (Republik Osterreich, 1976). A hazard zone map has to have a map part and a text part, the map part includes maps for hazards and for hazard zones. The text part describes contents of the maps and all official steps of the developing process. An Austrian statutory technical ordinance defines the design of hazard zone maps in Austria (Republik € Osterreich, 1976). To develop a hazard zone map is a complex process, it includes also the collection of statements of inhabitants living in respective village. It is the hydrologists who more and more seek to collect
Table 1 Austrians regulations about MRDM (Leitgeb & Rudolf-Miklau 2004). Politcal level
Law
Federal level
Federal State level
Local level (municipalities)
Water Act Forest Act Torrent Control Act Water Construction Financing Act Disaster Relief Fund Act Ordinance on Hazard Zone Mapping Guidelines on Hazard Zone Mapping Technical Directive for Torrent and Avalanche Control Directive for Cost-Benefit-Analysis on Torrent and Avalanche Control Measures Civil Protection Acts Areal Planning Regulations Building trade Acts Hazard Zone Maps of Torrents and Avalanches Area planning scheme Local development concepts Development scheme Planning and building permissions Alarm and action plans for catastrophes
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historical information, especially where modern science has not been able to provide them with sufficient data (Barnikel & Becht 2003). The final hazard zone map is a combined result of engineering, modern hydrological and hydraulic analysis programs and statements of inhabitants respected by a technical commission. The commission decides if statements are strong enough to change parts of the hazard zones. After the commission agreed the correctness of the hazard zone map it gets a public document. The municipalities have to respect their hazard zone map and have to adapt their spatial planning. From 1975 until the middle of the 90's hazard zone maps were made by hand and many times on oversized and inconvenient to use big plans. With colored pencils different hazard zones caused by torrents and avalanches were drawn on actual plans of the land register. For the first time in the middle of the 90's the computer with qualified CAD programs changed the way of planning projects and hazard zone maps. Already in 1996 an Austrian journal published that there will be a need for newer planning instruments in the nearest future (Seewald, 1996). With a new revolution in IT world arose a change from analog to digital TAC in the end of the 90's. GIS made it possible to develop digital TAC. Digital TAC help in the process of planning and analyzing measures, developing hazard zone maps and generating expert statements and reports to be used for other projects in torrent and avalanche areas. The main purpose of using GIS is to support MRDM in different forms. First of all, it is going to be a big digital storage for geographic based information about torrent catchment areas, hazard zone maps, past disasters etc. A properly maintained digital archive makes it easier to get information and to analyze risks in a certain area or a village for future strategic steering, projects and budgeting, as well as to reduce the need for paper archives. 3. GIS used for torrent and avalanche cadaster GIS are computer-based systems designed to capture, store, analyze and display data related to positions on Earth's surface. GIS allows multiple layers of different kind of information to be displayed on a single map (Fig. 3). This enables easier identification, analysis and understanding of patterns and relationships. Entering information into GIS is called data capture. Data that are already in digital form, such as images taken by satellites, or data created in other programs, can easily be uploaded into GIS. Analog maps like old hazard zone maps made by hand must be scanned and digitized. Austrian federal Forest Act enforced keeping a TAC in Austria since 1975. Since 2004 Austrian Service for Torrent and Avalanche Control has started the development of the GIS based TAC. As basic program ArcGIS is used, now in version 10.1. GIS has a layer-based digitizing concept which includes existing layers and new layers for digitizing. In TAC orthophotos, Austrian map, digital land register and other similar data are used as existing layers. It is possible to import other layers if it is useful for digitizing. This basic information layers are imported from external sources. It is very important to check their quality first. Basic information with a good quality makes the output during digitizing better. Because different imported maps exist in different types of projections GIS also manipulates digital data. A projection is the method of transferring information from Earth's curved surface to a flat piece of paper or computer screen. No projection is able to create a perfect copy of Earth's curved surface. Different types of projections accomplish this task in different ways, but every projection contains some distortion. To transfer a curved, threedimensional shape onto a flat surface inevitably requires
Fig. 3. GIS combines different layers, each layer contains one certain type of data (National Geographic Society, 2014).
stretching some parts and squeezing other parts. GIS takes data from maps which were made in different projections and combines them. All collected information can then be displayed in one common projection (National Geographic Society, 2014). For each type of data a separate layer is created. For example, one layer shows orthophotos, a second layer laser scan data and a third axis of torrents etc. Layers are different in shape and information about their objects. The shape of the objects can be raster data or vector data. Vector data differ in points, lines and area layers. Each layer is designed in its symbologies (National Geographic Society, 2014). The objects are represented by a unique identification number and each object carries attached information characterized by a table of numbers and texts. Once all related data have been entered into the GIS system, they can be combined to produce a wide variety of individual maps, depending on which data layers are included. Any GIS data layer can be added or subtracted to the map. GIS maps can be used to show information about the situation in past and present. Researchers can compare changes over time like dimensions of forests and settlements. With the possibility to look at amounts of points, length of lines and dimensions of areas statistics for future strategic steering and decisions can be designed. Because the work in MRDM is very complex, the TAC is diverted in different modules which have different characters but are also interacting. Each module has its own workflow in GIS for digitizing. Modules:
Torrent areas Avalanche areas Other risk areas (erosion, rock fall, landslips) Hazard zone maps Constructions cadaster Expert statement cadaster Projects cadaster Disaster cadaster Basic information cadaster
Primarily for torrents catchment areas and water bodies are to be defined. With meteorological inputs and by the use of mudflow models and rainfall runoff models accumulation areas can be
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calculated and digitized. The same is the case with avalanches. The digitized avalanche catchment area and the estimated or calculated avalanche flow results in an accumulation area. Extra risk areas module is used for other catchment areas which do not belong to torrents or avalanches, e.g. erosion, rock fall, landslips. The first three modules are important for next modules. Hazard zones, projects, disasters and constructions belong to already digitized torrents and avalanches. Only when catchment areas are digitized in a good quality it is also possible to ensure a good quality for hazard zones, disaster analysis and new project definitions. Expert statements need information from all other modules. So the modules exist in an interactive information network. The basic information cadaster is used only for displaying imported data from external sources, therefore it's also important to check the quality of these data. Because GIS used for TAC is getting bigger and bigger it is combined with a database. Each module is included also in the database. Geographical information like length and area dimensions is sent after digitization in GIS to the database. Normally, the database alone is used for administrative work and thus the database becomes the digital archive for future needs. A screenshot in Fig. 4 shows the module control window in which the modules in the database can be switched on and off. Equal if it is a torrent, avalanche, hazard zone map or construction in the database each object has a unique TAC number. This number is automatically assigned by the database when a new object is digitized. Through the workflow in each module first the geographical shape of the object is drawn. Thereafter, this object gets a name and during the upload into the database it gets a new TAC number. Of course it is possible to redraw an object when mistakes were made or changes are necessary, but with this unique TAC number each object becomes unmistakable identifiable. 4. Examples for torrent and avalanche cadaster in GIS GIS used as TAC is a mixture of technical and administrative tool. As basic information orthophotos, land-use maps, contour lines, digital land register etc. are used. As they are implemented as basic layers from external data sources the quality of this data has to be checked. A good quality is shown when different data matches geographically, e.g. contour lines and orthophotos match each other and show perfectly the trench of water routes (Fig. 5). In Fig. 6, four layers are switched on: catchment area, torrent, orthophoto and competence point. 14 catchment areas of torrents can be seen. Underlined are main torrents and without underline sub torrents. In some places there is still a need for renewing the digitization, mistakes can be found between Weidenbach and Friedhofgraben II, and some water bodies are not finished yet. In Austrian water bodies exists a separation in torrents and rivers. Regulated by Austrian federal laws Austrian Service for Torrent and Avalanche Control is only responsible for torrents and not for rivers. The yellow (in the web version) dots show the competence points which define the boundaries of the responsibility for Austrian Service for Torrent and Avalanche Control. Downstream of the competence points the water body is a river, upstream a torrent. For rivers is no catchment area defined by Austrian Service for Torrent and Avalanche Control. A screenshot for the hazard zone map module is demonstrated in Fig. 7. Above the orthophoto six layers are visible. The catchment areas of eight torrents are visible without the water bodies and only the boundaries. The striped space is a settlement within the hazard zones are evaluated.
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Fig. 4. Screenshot taken from TAC database; Translation: Modulsteuerung ¼ module control, Wildbach ¼ torrent, Lawine ¼ avalanche, Gefahrenzonenplan ¼ hazard zone map, Gutachten ¼ expert statement, Projekte ¼ projects, Ereignisse ¼ disaster, Dokumente ¼ documents, Basisdaten ¼ basic information, Bauwerke ¼ constructions, Sonstige Gefahrengebiete ¼ extra risk areas, Gemeinde ¼ village, Gebietsbauleitung ¼ regional administration office (Austrian Service for Torrent and Avalanche Control is regional divided.); screenshot of Austrian TAC, 2015.
5. Analysis and export of GIS data GIS has two main purposes, on one hand data capture, digitizing and storing information and on the other hand searching for information, analyzing and using it for future needs. Alone to digitize and store data in GIS is not the whole sense of this system, it allows to design statistics and export data for internal and external usage. Because of the connection of GIS with a database it is possible to analyze data differently and support decision makings. The TAC is separated in modules. For internal usage each exported data from one module can be used as basic information in another module. The hazard zone maps module needs catchment areas of torrents and avalanches as basic information. The catchment area is digitized in the torrent areas module. The shape and the names of the torrent catchment areas are imported into the hazard zone maps module. In the database the different modules are interconnected too. As examples, the torrents in the torrent areas module know in which village they are situated and if they produce hazards in settlements; hazard zones in the hazard zone maps module know their geographical position, which settlement areas in villages are in danger and which torrents or avalanches are causing them, etc. With TAC supported by GIS it is possible to analyze data about a defined topic within a short period of time. For example, for planning hazard zone maps it is necessary to get all information about torrents, avalanches and other mountain hazards in this area. Meteorological information about catchment areas and river systems are as important as already build retention basins and changes in settlement areas. Furthermore, data of past disasters better the analysis of possible floods or impacts. A second example, to realize new constructions against flood risks of torrents it is good to know if there are already older constructions and in which condition they are. The geographical
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Fig. 5. Layers fit together; as background layer orthophotos and above the layer “contour lines”, both layers are as basic information imported in GIS, the water routes were constructed; screenshot of Austrian TAC, 2015.
Fig. 6. Torrent areas module; four layers are switched on: catchment area, torrent, competence point and as background orthophoto; some catchment areas have mistakes and need a change in digitization; screenshot of Austrian TAC, 2015.
position of existing constructions can be seen on the GIS map. Additional knowledge about the amount of retention water makes it possible to calculate, how much space is needed for this construction and helps in geotechnical and static calculations as well as in assessment of costs for implementation of this construction. A third example, financing measures in Austria is based in Water Construction Financing Act which splits the costs up to the federal catastrophe fund, the federal states and local beneficiaries. With a well-maintained TAC it is possible to support generating statistics
about existing measures, for spatial planning and for future budget planning. Because MRDM is a national task TAC in Austria is primarily a tool for the employees inside the departments of Austrian Service for Torrent and Avalanche Control; it shall make some work processes easier and standardized and shall reduce paper work and paper archives. Only employees are allowed to change, delete and add data. External persons have no direct access. However, some of these tasks like the development of hazard zone maps become public domain documents. Today nearly
E. Lepuschitz / Applied Geography 63 (2015) 212e219
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Fig. 7. Hazard zone maps module; seven layers are visible: orthophoto, catchment area, settlement, red, yellow, blue and brown zones; screenshot of Austrian TAC, 2015. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
everybody has internet access. Villages, different federal and provincial departments are using internet access for representative and informational connections between departments and for public information supply. Public documents or digital public information can be shown at WebGIS portals with permanent public access. With the help of data tunnel public hazard zone maps are exported from TAC to these WebGIS portals. As example (Fig. 8) some data are represented from the province of Lower Austria in today's digitization status. In Lower Austria the summarized torrent catchment areas have around 7000 km2 (see Table 1 in Lepuschitz, submitted for publication). At the moment the sum of the length of the torrent water bodies amounts to approx. 7500 km. In 302 villages exists already a digital version of their hazard zone map (see Table 2 in Lepuschitz, submitted for publication). These maps can also be viewed in the provincial WebGIS portal with permanent public access from Lower Austria € Atlas” (Fig. 9). called “NO € Atlas the detail is in a smaller scale and In the screenshot of NO the digitization status of each village is shown, green villages have an actual digital hazard zone map, red and pink villages have only analog versions or are not finished digitized at the moment, white villages won't get a hazard zone map because no torrent or avalanche catchment area affects them. In bigger scales the appearance of the displayed landscape changes to a similar type like in Fig. 7 and shows the hazard zones in villages with an actual digital hazard zone map. In the database it's possible to confirm if the technical and legal work is correct, without this confirmation no data is transferred to public WebGIS portals. The export of digital data for public access is only done for torrent and avalanche areas and hazard zone maps. Data of these modules are transferred automatically when the confirmation is set. Data of other modules are not transferred
automatically, only when a request is sent to the department a manually export is possible. A new development is the mobile TAC for tablets. This development was worked out by Austrian Service for Torrent and Avalanche Control together with a private programming company, it was ready to use since 2014. A TAC app was new designed for offline work outdoors. Now and in the next future it shall be used for evaluating existing constructions, if this new technology works well other applications will be added. It is possible to export data from an office PC to a tablet only for offline use. In view of data security and database reasons TAC has no public internet access, it's not possible to get internet connection between TAC and tablets outdoors, these tablets also don't need sim cards then. After the work outdoors is finished data are stored back to TAC system in the office. If outdoors beside the evaluation of existing constructions new constructions were added these new constructions get their unique TAC number during uploading process into the database. 6. Conclusions Mountain risk and disaster management (MRDM) is mostly focused by federal interests because villages, public streets and railway tracks are affected by alpine natural hazards. That's the reason why MRDM is a national task. MRDM is a very complex system because many different participants are taking part in it. It contains many technical and administrative components which shall work together flawlessly and as ideal as possible without doubts and failures. With new criteria like sustainability, ecology and environment protection the handling of projects becomes more complex. TAC supports parts of the MRDM circle (Fig. 2). After a disaster event damage and impact assessments are recorded and in the case
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E. Lepuschitz / Applied Geography 63 (2015) 212e219
Fig. 8. Overview of torrent catchment areas and water bodies in Lower Austria, screenshot of Austrian TAC, April 2015.
€ Atlas, May 2015 (Land Niedero € sterreich, 2015). Fig. 9. Screenshot of WebGIS portal NO
of destroyed constructions they will be restored or new built. In GIS the geographical position of the disaster is shown and descriptions about impact range, impact time, destroyed buildings and other information are stored in TAC database. Also the state of the constructions is recorded in the database and when they have to be and are reconstructed this information will be recorded too. In the period of mitigation and prevention decisions are made about which new measures are planned and realized to reduce the possibility of disaster risks in the future. Mitigation and prevention are done in times when disasters are not happening. With experiences from past disasters, financial steering and negotiations between all
participants and public financiers are carried on and decisions are made. A big desire of all participants in MRDM is to get solutions with convenient handling in this complexity. The torrent and avalanche cadaster with GIS support is a technology for combining technical and administrative components and tries to simplify the system. Of course this technology is very young and because of its complexity it is always exposed to changes. Like the new mobile TAC for tablets every new element needs a lot of experience for further improvement.
E. Lepuschitz / Applied Geography 63 (2015) 212e219
Acknowledgment Many thanks to Ingo Schnetzer, technical staff member of Austrian Ministry for Agriculture, Forestry, Environment and Water Management and ms.gis informationssysteme GesmbH (www. msgis.com), who have mainly developed together Austrian digital TAC and allowed me to publish this paper, further to Johannes Hübl and Sven Fuchs of the Institute of Mountain Risk Engineering at the University of Natural Resources and Life Sciences, Vienna. References Barnikel, F., & Becht, M. (2003). A historical analysis of hazardous events in the Alps e the case of hindelang (Bavaria, Germany). NHESS Natural Hazards and Earth System Science, 3(6), 625e635. €tzing, W. (1993). Der sozio-o €konomische Strukturwandel des Alpenraumes im 20. Ba Jahrhundert (vol. P26). Geographica Bernensia (in german). FAO. (2004). Chapter 1, drought and climate variability in the Limpopo River Basin. In drought impact mitigation and prevention in the Limpopo River Basin, a situation analysis. Rome: Food and Agriculture Organization of the United Nations (FAO), Natural Resources Management and Environment Department, FAO
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Subregional Office for Southern and East Africa Harare. Keiler, M. (2004). Development of the damage potential resulting from avalanche risk in the period 1950e2005, case study Galtür. NHESS Natural Hazards and Earth System Science, 4(2), 249e256. € atlas. atlas.noe.gv.at (Accessed: May 2015) in €sterreich. (2015). NO Land Niedero german. Leitgeb, M., & Rudolf-Miklau, F. (2004). Risk and disaster management in natural hazards as floods, debris flows, landslides, rockfall and avalanches in Austria. In Interpraevent 2004. Riva del Garda. Lepuschitz, Ehrenfried. Statistics about torrents in Lower Austria, status from May 2015 (Data in Brief, submitted for publication). National Geographic Society. (2014). GIS (geographic information system) (Accessed: December 2014) in english education.nationalgeographic.com/education/ encyclopedia/geographic-information-system-gis. € Republik Osterreich. (1975). Forstgesetz (ForstG) 1975 idgF (in german). € Republik Osterreich. (1976). Verordnung des Bundesministers für Land- und For€ne (GZP-VO) idgF (in stwirtschaft vom 30. Juli 1976 über die Gefahrenzonenpla german). Seewald, W. (1996). Der digitale Wildbach- und Lawinenkataster, Ein Planungsinstrument für eine naturnahe Wildbach- und Lawinenverbauung (vol. 131, pp. 85e96). Wildbach- und Lawinenverbau (in german). Turconi, L., Nigrelli, G., & Conte, R. (2014). Historical datum as a basis for a new GIS application to support civil protection services in NW Italy. Computers & Geosciences, 66, 13e19.
Contents lists available at ScienceDirect
Applied Geography journal homepage: www.elsevier.com/locate/apgeog
Geographic information systems in mountain risk and disaster management Ehrenfried Lepuschitz Scientific Staff Member of the Institute of Mountain, Risk Engineering at the University of Natural Resources and Life Sciences, Vienna, Austria
a r t i c l e i n f o
a b s t r a c t
Article history: Received 23 March 2015 Received in revised form 26 June 2015 Accepted 26 June 2015 Available online xxx
Mountain risk and disaster management (MRDM) and natural hazards are in alpine countries a national task. Natural hazards in alpine spaces are represented by floods, avalanches, landslides, rock falls and debris flows. MRDM is a very complex system which includes many technical and administrative components. MRDM is based on legal acts and regulations enforced by different federal political levels and departments. A big desire of all involved participants in MRDM is to get simple solutions in this complexity. Austrian Service for Torrent and Avalanche Control has to keep a TAC. With the support of geographic information systems (GIS) it was possible to create a digital TAC. The digital TAC is diverted into different modules: torrent areas, avalanche areas, hazard zone maps, etc. Each module has its own character, but act also interactive. In view of data security TAC has no public access. For public information supply objects can be exported from digital TAC. Only when technical and legal work of an object is correct it can be send through a data tunnel to WebGIS portals with permanent public access for further public use. This paper gives a basic insight into digital TAC supported by GIS which is used in the offices of Austrian Service for Torrent and Avalanche Control. © 2015 Elsevier Ltd. All rights reserved.
Keywords: Mountain risk and disaster management Natural hazards Torrent and avalanche cadaster Hazard zones Geographic information system Digitizing
1. Introduction The risk resulting from natural hazards can be derived from the combination of parameters of physical processes and the damage potential (Keiler, 2004). The damage potential or vulnerability is also influenced by the development of the society. The alpine society has undergone enormous socio-economic changes; the shift from an agricultural society to a modern service industry and leisure oriented society is reflected by an increasing usage of the Alps as an area of settlement, economic activities and leisure (B€ atzing, 1993). The quality of the buildings and their equipment has increased significantly, mainly in order to meet the demands of the tourism industry, reinsurance companies have been pointing out the worldwide trend of increasing damage sums caused by natural hazards. Even though the damage potential has been taken into account more frequently (Keiler, 2004). Controlling natural hazards is a national task of paramount importance to ensure maximum safety, through sustainable strategies in the integrated risk management of natural hazards in mountainous watersheds (Turconi, Nigrelli, & Conte, 2014).
E-mail addresses: [email protected], [email protected]. http://dx.doi.org/10.1016/j.apgeog.2015.06.014 0143-6228/© 2015 Elsevier Ltd. All rights reserved.
Mountain risk and disaster management (MRDM) works mainly with natural hazards in alpine regions comprising flooding, avalanches, landslides, rock falls and debris flows. In the mountains torrents and avalanches become strengthened in catchment areas and cause hazards which threaten urban areas with flooding and avalanche impacts (Graphical Abstract, Fig. 1). Fig. 2 describes a comprehensive circle of disaster, risk and crisis management (FAO, 2004). One half reflects crisis management after disaster and the second half shows risk management before next disaster. The head of the crisis management is mostly the municipal council supported by firefighters and if necessary by volunteers and army. The period of mitigation and prevention pursues the aim to reduce the risk of damage by disaster. It comprises analysis of past disaster, creation of concepts by research and development, project planning and realization, identification of vulnerability with the help of hazard zone maps and financial planning. 2. Austrian approach to MRDM In Austria MRDM is based on federal law, regulations and ordinances. Austria is politically divided into federal provinces and municipalities. Each federal political level has its own legal acts and
E. Lepuschitz / Applied Geography 63 (2015) 212e219
Fig. 1. Torrents and avalanches become strengthened in catchment areas and cause hazards which threaten urban areas, Graphical Abstract.
Fig. 2. Disaster, risk and crisis management circle; crisis management happens after disaster, risk management before next disaster (FAO, 2004).
regulations which are equally applied and complement each other (Table 1). Based on these regulations, Austrian Ministry for Agriculture, Forestry, Environment and Water Management is in charge of strategic steering in MRDM. In Austrian water bodies exists a separation in torrents and rivers. This has mainly a historical reason but which is still existing. On the one hand, in the federal Water Act, legislated in 1959 and adapted to the European Water Framework Directive (Directive 2000/60/EC), the administration for river management is delegated to the federal provinces. Each Austrian federal province has own Technical Water Engineering and Water Management Offices. On the other hand, in 1884, when Austria was still part of the AustrianeHungarian monarchy Austrian Service for Torrent and Avalanche Control was founded by a torrent regulation law to act against natural hazards caused by torrents. The main mission was to plan, develop and finance constructions. Today torrents are together with avalanches regulated by the federal Forest Act, legislated in 1975. Hence, Austrian Service for Torrent and Avalanche Control and Technical Water Engineering and Water Management Offices of the Provincial Governments administrate together with municipalities MRDM.
213
Technical terms are defined and described by Austrian federal Forest Act of 1975. A torrent is a permanent or temporary water body which takes and carries dangerous amounts of sediments from the catchment area and its river bed with a strong rise in the water level within a short period of time and stores these sediments inside or outside the river bed or in another water body € (Republik Osterreich, 1975). This characteristic can happen only in mountainous regions, therefore torrents exist only there. Lowlands are mostly free of torrents (see Figs. 2 and 3 in Lepuschitz, submitted for publication). An avalanche consists of huge snow masses which causes hazardous situations and damage because of its kinetic energy or air pressure gained from steep slopes and trenches (Republik € Osterreich, 1975). For better administration the Forest Act defined in Austria the first time that Austrian Service for Torrent and Avalanche Control had to keep a torrent and avalanche cadaster (TAC, Republik € Osterreich, 1975). Already in the 80's and beginning 90's a research group started the realization of a TAC but first only in an analog way. Another field of work is to develop hazard zone maps for each village which is affected by torrents or avalanches. Each torrent and avalanche has a catchment area which causes red and yellow hazard zones in settlements. Other hazard zones which are caused by rock fall, erosion or landslips are shown as brown hazard zones. Furthermore, it's possible to include other colored hazard zones for future measures. Future measures can be active or passive. Active measures are e.g. retention basins in torrents (blue zones) and passive measures are e.g. natural areas where shape and quality of the soil shall not be changed (violet zones). The areas of hazard € zones are to be held free from other buildings (Republik Osterreich, 1976). A hazard zone map has to have a map part and a text part, the map part includes maps for hazards and for hazard zones. The text part describes contents of the maps and all official steps of the developing process. An Austrian statutory technical ordinance defines the design of hazard zone maps in Austria (Republik € Osterreich, 1976). To develop a hazard zone map is a complex process, it includes also the collection of statements of inhabitants living in respective village. It is the hydrologists who more and more seek to collect
Table 1 Austrians regulations about MRDM (Leitgeb & Rudolf-Miklau 2004). Politcal level
Law
Federal level
Federal State level
Local level (municipalities)
Water Act Forest Act Torrent Control Act Water Construction Financing Act Disaster Relief Fund Act Ordinance on Hazard Zone Mapping Guidelines on Hazard Zone Mapping Technical Directive for Torrent and Avalanche Control Directive for Cost-Benefit-Analysis on Torrent and Avalanche Control Measures Civil Protection Acts Areal Planning Regulations Building trade Acts Hazard Zone Maps of Torrents and Avalanches Area planning scheme Local development concepts Development scheme Planning and building permissions Alarm and action plans for catastrophes
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historical information, especially where modern science has not been able to provide them with sufficient data (Barnikel & Becht 2003). The final hazard zone map is a combined result of engineering, modern hydrological and hydraulic analysis programs and statements of inhabitants respected by a technical commission. The commission decides if statements are strong enough to change parts of the hazard zones. After the commission agreed the correctness of the hazard zone map it gets a public document. The municipalities have to respect their hazard zone map and have to adapt their spatial planning. From 1975 until the middle of the 90's hazard zone maps were made by hand and many times on oversized and inconvenient to use big plans. With colored pencils different hazard zones caused by torrents and avalanches were drawn on actual plans of the land register. For the first time in the middle of the 90's the computer with qualified CAD programs changed the way of planning projects and hazard zone maps. Already in 1996 an Austrian journal published that there will be a need for newer planning instruments in the nearest future (Seewald, 1996). With a new revolution in IT world arose a change from analog to digital TAC in the end of the 90's. GIS made it possible to develop digital TAC. Digital TAC help in the process of planning and analyzing measures, developing hazard zone maps and generating expert statements and reports to be used for other projects in torrent and avalanche areas. The main purpose of using GIS is to support MRDM in different forms. First of all, it is going to be a big digital storage for geographic based information about torrent catchment areas, hazard zone maps, past disasters etc. A properly maintained digital archive makes it easier to get information and to analyze risks in a certain area or a village for future strategic steering, projects and budgeting, as well as to reduce the need for paper archives. 3. GIS used for torrent and avalanche cadaster GIS are computer-based systems designed to capture, store, analyze and display data related to positions on Earth's surface. GIS allows multiple layers of different kind of information to be displayed on a single map (Fig. 3). This enables easier identification, analysis and understanding of patterns and relationships. Entering information into GIS is called data capture. Data that are already in digital form, such as images taken by satellites, or data created in other programs, can easily be uploaded into GIS. Analog maps like old hazard zone maps made by hand must be scanned and digitized. Austrian federal Forest Act enforced keeping a TAC in Austria since 1975. Since 2004 Austrian Service for Torrent and Avalanche Control has started the development of the GIS based TAC. As basic program ArcGIS is used, now in version 10.1. GIS has a layer-based digitizing concept which includes existing layers and new layers for digitizing. In TAC orthophotos, Austrian map, digital land register and other similar data are used as existing layers. It is possible to import other layers if it is useful for digitizing. This basic information layers are imported from external sources. It is very important to check their quality first. Basic information with a good quality makes the output during digitizing better. Because different imported maps exist in different types of projections GIS also manipulates digital data. A projection is the method of transferring information from Earth's curved surface to a flat piece of paper or computer screen. No projection is able to create a perfect copy of Earth's curved surface. Different types of projections accomplish this task in different ways, but every projection contains some distortion. To transfer a curved, threedimensional shape onto a flat surface inevitably requires
Fig. 3. GIS combines different layers, each layer contains one certain type of data (National Geographic Society, 2014).
stretching some parts and squeezing other parts. GIS takes data from maps which were made in different projections and combines them. All collected information can then be displayed in one common projection (National Geographic Society, 2014). For each type of data a separate layer is created. For example, one layer shows orthophotos, a second layer laser scan data and a third axis of torrents etc. Layers are different in shape and information about their objects. The shape of the objects can be raster data or vector data. Vector data differ in points, lines and area layers. Each layer is designed in its symbologies (National Geographic Society, 2014). The objects are represented by a unique identification number and each object carries attached information characterized by a table of numbers and texts. Once all related data have been entered into the GIS system, they can be combined to produce a wide variety of individual maps, depending on which data layers are included. Any GIS data layer can be added or subtracted to the map. GIS maps can be used to show information about the situation in past and present. Researchers can compare changes over time like dimensions of forests and settlements. With the possibility to look at amounts of points, length of lines and dimensions of areas statistics for future strategic steering and decisions can be designed. Because the work in MRDM is very complex, the TAC is diverted in different modules which have different characters but are also interacting. Each module has its own workflow in GIS for digitizing. Modules:
Torrent areas Avalanche areas Other risk areas (erosion, rock fall, landslips) Hazard zone maps Constructions cadaster Expert statement cadaster Projects cadaster Disaster cadaster Basic information cadaster
Primarily for torrents catchment areas and water bodies are to be defined. With meteorological inputs and by the use of mudflow models and rainfall runoff models accumulation areas can be
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calculated and digitized. The same is the case with avalanches. The digitized avalanche catchment area and the estimated or calculated avalanche flow results in an accumulation area. Extra risk areas module is used for other catchment areas which do not belong to torrents or avalanches, e.g. erosion, rock fall, landslips. The first three modules are important for next modules. Hazard zones, projects, disasters and constructions belong to already digitized torrents and avalanches. Only when catchment areas are digitized in a good quality it is also possible to ensure a good quality for hazard zones, disaster analysis and new project definitions. Expert statements need information from all other modules. So the modules exist in an interactive information network. The basic information cadaster is used only for displaying imported data from external sources, therefore it's also important to check the quality of these data. Because GIS used for TAC is getting bigger and bigger it is combined with a database. Each module is included also in the database. Geographical information like length and area dimensions is sent after digitization in GIS to the database. Normally, the database alone is used for administrative work and thus the database becomes the digital archive for future needs. A screenshot in Fig. 4 shows the module control window in which the modules in the database can be switched on and off. Equal if it is a torrent, avalanche, hazard zone map or construction in the database each object has a unique TAC number. This number is automatically assigned by the database when a new object is digitized. Through the workflow in each module first the geographical shape of the object is drawn. Thereafter, this object gets a name and during the upload into the database it gets a new TAC number. Of course it is possible to redraw an object when mistakes were made or changes are necessary, but with this unique TAC number each object becomes unmistakable identifiable. 4. Examples for torrent and avalanche cadaster in GIS GIS used as TAC is a mixture of technical and administrative tool. As basic information orthophotos, land-use maps, contour lines, digital land register etc. are used. As they are implemented as basic layers from external data sources the quality of this data has to be checked. A good quality is shown when different data matches geographically, e.g. contour lines and orthophotos match each other and show perfectly the trench of water routes (Fig. 5). In Fig. 6, four layers are switched on: catchment area, torrent, orthophoto and competence point. 14 catchment areas of torrents can be seen. Underlined are main torrents and without underline sub torrents. In some places there is still a need for renewing the digitization, mistakes can be found between Weidenbach and Friedhofgraben II, and some water bodies are not finished yet. In Austrian water bodies exists a separation in torrents and rivers. Regulated by Austrian federal laws Austrian Service for Torrent and Avalanche Control is only responsible for torrents and not for rivers. The yellow (in the web version) dots show the competence points which define the boundaries of the responsibility for Austrian Service for Torrent and Avalanche Control. Downstream of the competence points the water body is a river, upstream a torrent. For rivers is no catchment area defined by Austrian Service for Torrent and Avalanche Control. A screenshot for the hazard zone map module is demonstrated in Fig. 7. Above the orthophoto six layers are visible. The catchment areas of eight torrents are visible without the water bodies and only the boundaries. The striped space is a settlement within the hazard zones are evaluated.
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Fig. 4. Screenshot taken from TAC database; Translation: Modulsteuerung ¼ module control, Wildbach ¼ torrent, Lawine ¼ avalanche, Gefahrenzonenplan ¼ hazard zone map, Gutachten ¼ expert statement, Projekte ¼ projects, Ereignisse ¼ disaster, Dokumente ¼ documents, Basisdaten ¼ basic information, Bauwerke ¼ constructions, Sonstige Gefahrengebiete ¼ extra risk areas, Gemeinde ¼ village, Gebietsbauleitung ¼ regional administration office (Austrian Service for Torrent and Avalanche Control is regional divided.); screenshot of Austrian TAC, 2015.
5. Analysis and export of GIS data GIS has two main purposes, on one hand data capture, digitizing and storing information and on the other hand searching for information, analyzing and using it for future needs. Alone to digitize and store data in GIS is not the whole sense of this system, it allows to design statistics and export data for internal and external usage. Because of the connection of GIS with a database it is possible to analyze data differently and support decision makings. The TAC is separated in modules. For internal usage each exported data from one module can be used as basic information in another module. The hazard zone maps module needs catchment areas of torrents and avalanches as basic information. The catchment area is digitized in the torrent areas module. The shape and the names of the torrent catchment areas are imported into the hazard zone maps module. In the database the different modules are interconnected too. As examples, the torrents in the torrent areas module know in which village they are situated and if they produce hazards in settlements; hazard zones in the hazard zone maps module know their geographical position, which settlement areas in villages are in danger and which torrents or avalanches are causing them, etc. With TAC supported by GIS it is possible to analyze data about a defined topic within a short period of time. For example, for planning hazard zone maps it is necessary to get all information about torrents, avalanches and other mountain hazards in this area. Meteorological information about catchment areas and river systems are as important as already build retention basins and changes in settlement areas. Furthermore, data of past disasters better the analysis of possible floods or impacts. A second example, to realize new constructions against flood risks of torrents it is good to know if there are already older constructions and in which condition they are. The geographical
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Fig. 5. Layers fit together; as background layer orthophotos and above the layer “contour lines”, both layers are as basic information imported in GIS, the water routes were constructed; screenshot of Austrian TAC, 2015.
Fig. 6. Torrent areas module; four layers are switched on: catchment area, torrent, competence point and as background orthophoto; some catchment areas have mistakes and need a change in digitization; screenshot of Austrian TAC, 2015.
position of existing constructions can be seen on the GIS map. Additional knowledge about the amount of retention water makes it possible to calculate, how much space is needed for this construction and helps in geotechnical and static calculations as well as in assessment of costs for implementation of this construction. A third example, financing measures in Austria is based in Water Construction Financing Act which splits the costs up to the federal catastrophe fund, the federal states and local beneficiaries. With a well-maintained TAC it is possible to support generating statistics
about existing measures, for spatial planning and for future budget planning. Because MRDM is a national task TAC in Austria is primarily a tool for the employees inside the departments of Austrian Service for Torrent and Avalanche Control; it shall make some work processes easier and standardized and shall reduce paper work and paper archives. Only employees are allowed to change, delete and add data. External persons have no direct access. However, some of these tasks like the development of hazard zone maps become public domain documents. Today nearly
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Fig. 7. Hazard zone maps module; seven layers are visible: orthophoto, catchment area, settlement, red, yellow, blue and brown zones; screenshot of Austrian TAC, 2015. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
everybody has internet access. Villages, different federal and provincial departments are using internet access for representative and informational connections between departments and for public information supply. Public documents or digital public information can be shown at WebGIS portals with permanent public access. With the help of data tunnel public hazard zone maps are exported from TAC to these WebGIS portals. As example (Fig. 8) some data are represented from the province of Lower Austria in today's digitization status. In Lower Austria the summarized torrent catchment areas have around 7000 km2 (see Table 1 in Lepuschitz, submitted for publication). At the moment the sum of the length of the torrent water bodies amounts to approx. 7500 km. In 302 villages exists already a digital version of their hazard zone map (see Table 2 in Lepuschitz, submitted for publication). These maps can also be viewed in the provincial WebGIS portal with permanent public access from Lower Austria € Atlas” (Fig. 9). called “NO € Atlas the detail is in a smaller scale and In the screenshot of NO the digitization status of each village is shown, green villages have an actual digital hazard zone map, red and pink villages have only analog versions or are not finished digitized at the moment, white villages won't get a hazard zone map because no torrent or avalanche catchment area affects them. In bigger scales the appearance of the displayed landscape changes to a similar type like in Fig. 7 and shows the hazard zones in villages with an actual digital hazard zone map. In the database it's possible to confirm if the technical and legal work is correct, without this confirmation no data is transferred to public WebGIS portals. The export of digital data for public access is only done for torrent and avalanche areas and hazard zone maps. Data of these modules are transferred automatically when the confirmation is set. Data of other modules are not transferred
automatically, only when a request is sent to the department a manually export is possible. A new development is the mobile TAC for tablets. This development was worked out by Austrian Service for Torrent and Avalanche Control together with a private programming company, it was ready to use since 2014. A TAC app was new designed for offline work outdoors. Now and in the next future it shall be used for evaluating existing constructions, if this new technology works well other applications will be added. It is possible to export data from an office PC to a tablet only for offline use. In view of data security and database reasons TAC has no public internet access, it's not possible to get internet connection between TAC and tablets outdoors, these tablets also don't need sim cards then. After the work outdoors is finished data are stored back to TAC system in the office. If outdoors beside the evaluation of existing constructions new constructions were added these new constructions get their unique TAC number during uploading process into the database. 6. Conclusions Mountain risk and disaster management (MRDM) is mostly focused by federal interests because villages, public streets and railway tracks are affected by alpine natural hazards. That's the reason why MRDM is a national task. MRDM is a very complex system because many different participants are taking part in it. It contains many technical and administrative components which shall work together flawlessly and as ideal as possible without doubts and failures. With new criteria like sustainability, ecology and environment protection the handling of projects becomes more complex. TAC supports parts of the MRDM circle (Fig. 2). After a disaster event damage and impact assessments are recorded and in the case
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Fig. 8. Overview of torrent catchment areas and water bodies in Lower Austria, screenshot of Austrian TAC, April 2015.
€ Atlas, May 2015 (Land Niedero € sterreich, 2015). Fig. 9. Screenshot of WebGIS portal NO
of destroyed constructions they will be restored or new built. In GIS the geographical position of the disaster is shown and descriptions about impact range, impact time, destroyed buildings and other information are stored in TAC database. Also the state of the constructions is recorded in the database and when they have to be and are reconstructed this information will be recorded too. In the period of mitigation and prevention decisions are made about which new measures are planned and realized to reduce the possibility of disaster risks in the future. Mitigation and prevention are done in times when disasters are not happening. With experiences from past disasters, financial steering and negotiations between all
participants and public financiers are carried on and decisions are made. A big desire of all participants in MRDM is to get solutions with convenient handling in this complexity. The torrent and avalanche cadaster with GIS support is a technology for combining technical and administrative components and tries to simplify the system. Of course this technology is very young and because of its complexity it is always exposed to changes. Like the new mobile TAC for tablets every new element needs a lot of experience for further improvement.
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Acknowledgment Many thanks to Ingo Schnetzer, technical staff member of Austrian Ministry for Agriculture, Forestry, Environment and Water Management and ms.gis informationssysteme GesmbH (www. msgis.com), who have mainly developed together Austrian digital TAC and allowed me to publish this paper, further to Johannes Hübl and Sven Fuchs of the Institute of Mountain Risk Engineering at the University of Natural Resources and Life Sciences, Vienna. References Barnikel, F., & Becht, M. (2003). A historical analysis of hazardous events in the Alps e the case of hindelang (Bavaria, Germany). NHESS Natural Hazards and Earth System Science, 3(6), 625e635. €tzing, W. (1993). Der sozio-o €konomische Strukturwandel des Alpenraumes im 20. Ba Jahrhundert (vol. P26). Geographica Bernensia (in german). FAO. (2004). Chapter 1, drought and climate variability in the Limpopo River Basin. In drought impact mitigation and prevention in the Limpopo River Basin, a situation analysis. Rome: Food and Agriculture Organization of the United Nations (FAO), Natural Resources Management and Environment Department, FAO
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Subregional Office for Southern and East Africa Harare. Keiler, M. (2004). Development of the damage potential resulting from avalanche risk in the period 1950e2005, case study Galtür. NHESS Natural Hazards and Earth System Science, 4(2), 249e256. € atlas. atlas.noe.gv.at (Accessed: May 2015) in €sterreich. (2015). NO Land Niedero german. Leitgeb, M., & Rudolf-Miklau, F. (2004). Risk and disaster management in natural hazards as floods, debris flows, landslides, rockfall and avalanches in Austria. In Interpraevent 2004. Riva del Garda. Lepuschitz, Ehrenfried. Statistics about torrents in Lower Austria, status from May 2015 (Data in Brief, submitted for publication). National Geographic Society. (2014). GIS (geographic information system) (Accessed: December 2014) in english education.nationalgeographic.com/education/ encyclopedia/geographic-information-system-gis. € Republik Osterreich. (1975). Forstgesetz (ForstG) 1975 idgF (in german). € Republik Osterreich. (1976). Verordnung des Bundesministers für Land- und For€ne (GZP-VO) idgF (in stwirtschaft vom 30. Juli 1976 über die Gefahrenzonenpla german). Seewald, W. (1996). Der digitale Wildbach- und Lawinenkataster, Ein Planungsinstrument für eine naturnahe Wildbach- und Lawinenverbauung (vol. 131, pp. 85e96). Wildbach- und Lawinenverbau (in german). Turconi, L., Nigrelli, G., & Conte, R. (2014). Historical datum as a basis for a new GIS application to support civil protection services in NW Italy. Computers & Geosciences, 66, 13e19.