THE IFFI PROJECT (ITALIAN LANDSLIDE INVENTORY): METHODOLOGY AND RESULTS Luca Guerrieri, Alessandro Trigila & Carla Iadanza Experts meeting on guidelines for mapping areas at risk of landslides in Europe JRC, Ispra 23-24 October 2007
CONTENTS Objectives Methodology IFFI dataset Data processing WebGIS & WMS Services
OBJECTIVES The IFFI Project aims at: identifying and mapping landslides over the whole Italian territory, based on standardized criteria; building up a National Landslide Geographic Information System; providing a tool for hazard and risk assessment and land use planning.
FINANCIAL SUPPORT AND INSTITUTIONAL COMPETENCES The project has been financed with 4.1 Mil. Euro by the Committee of Ministries for the Land Protection, established by the Italian Government (Law n. 183/89). The institutions involved in the IFFI Project are: a) APAT - Geological Survey of Italy/Land Protection and Georesources Department, with the task of organizing and coordinating the activities, developing the guidelines, verifying the data conformity, building up a national geodatabase and a WebGIS; b) Regions and Autonomous Provinces, charged to collect historical documents, archive data and map the areas affected by landslides.
METHODOLOGY The methodology applied to build up the Italian Landslide Inventory is based on aerial photo-interpretation, field surveys, historical documents and archive data. Aerial photo-interpretation (Volo GAI 1954) - Cetara basin (SA) - Campania Archives data - debris flow occurred in Cetara basin during 23-24 October 1910 event.
HISTORICAL DOCUMENTS & FIELD SURVEYS M. Falterona Falterona landslide - S. Godenzo (FI) 15 may 1335 described by Giovanni Villani in Cronica Fiorentina - Manuscript del XIV sec. Biblioteca Riccardiana, Florence. Extremely rapid mud-debris flow 30 april 2006, Ischia Island, 4 casualties.
MAIN DATA SOURCES The main sources of information consulted to compile the IFFI database are: National Projects (AVI - Inventory of information on sites historically affected by landslides and floods in Italy for the period 1918/2000; SCAI - Special project for the study of unstable towns; CARG -Geological map of Italy, scale 1:50,000); Landslide inventories by Regions, River Basin Autorities, Research Institutes, Universities; River Basin plans (PAI - L. 267/98); Emergency Declarations (L.225/92); National and local public archives; Scientific and technical papers and reports.
LANDSLIDE DATASHEET The IFFI Landslide Data Sheet is organised in three information levels of increasing detail: 1 st level contains the basic data on landslide location, type of movement and state of activity; 2 nd level provides data on morphometry, geological setting, lithology, land use, causes of activation, date of activation; 3 rd level gives detailed information on damages, investigation process and remedial measures for risk reduction.
CARTOGRAPHY Landslides are represented with: a georeferenced point, located at the highest point of the crown; a polygon, in case the landslide area is >10,000 square meters; a line, in case the width is too narrow and in case of debris flows. The mapping scale is 1:10,000 in the most part of Italian territory. However less resolution scale (1:25,000) has been used in mountain and sparsely populated areas.
IFFI GEO-DATABASE The IFFI geo-database contains vector layers of landslides and an alphanumeric archive of attributes (RDBMS). The relational alphanumeric database scheme is based on the Landslide Data Sheet.
LANDSLIDE ID The Landslide ID is a code whose values uniquely identify each landslide over the whole italian territory. This code links the alphanumeric attributes to the geographic features. Alphanumeric data base LANDSLIDE ID 0 2 4 0 0 0 4 1 0 0 Cartographic data base Province ISTAT code Progressive number inside province territory Sub-index for complex landslides
QUALITY CONTROL CHECKS All geometrical features of the IFFI Landslide Inventory must pass a series of validation rules before they are stored in the geo-database. APAT has defined two sets of quality control tasks: the first set, or initial set, consists of the Spatial data checks, the Attribute checks and the Geometry checks; the second one inspects the IFFI geographic data for completeness with other datasets: AVI, SCAI, CARG, PAIs. IFFI Verification Tools designed by APAT
RESULTS At present more than 460.000 landslides have been mapped, covering an area of about 19.700 km 2 (6,5% of the whole italian territory).
TYPE OF MOVEMENT Area affected by rock-fall/topple 11,5% Area affected by shallow landslides 5,3% n.d. 4,5% Rock-fall and topple 3,4% Rotational and translational slide 32,8% Deep Seated Gravitational Slope Deformation 0,3% Lateral spread 0,1% Complex landslide 11,6% Sinkhole 0,1% Extremely rapid debris flow 14,9% Slow earth flow 15,5%
TYPE OF MOVEMENT Rock topples - Dorgali (NU) - Sardegna Roto-traslational slide evolving in slow earth flow - Ripalimosani (CB) - Molise
10000 9000 8000 7000 6000 5000 4000 3000 2000 1000 0 PREDISPOSING AND PREDISPOSING AND TRIGGERING FACTORS 8710 8655 5701 4091 4110 3000 2763 2109 1745 1444 1055 Rapid debris flow - Cervinara (AV) dicember 1999 - Forest road Weak material Weathered material Sheared material Jointed or fissured material Contrast in permeability Intense rainfall Prolonged exceptional precipitation Freezen and thaw wheathering Shrink and swell weathering Fluvial erosion of slope toe Excavation of slope or its toe
DATA PROCESSING & LANDSLIDE RISK Input data: IFFI Landslide Inventory; CORINE Land Cover 2000 archive; Road and railway networks; Digital orthophoto (Terraitaly it2000); Municipality boundary. Output data: Landslides & infrastructures; Landslide risk analysis in the italian municipalities.
LANDSLIDES AND URBAN AREAS Cerzeto (CS) - Calabria Sarno & Quindici (SA) 6/05/1998 400 Extremely rapid debris flows 160 Fatalities Landslides (in red) urban areas (in yellow) Digital orthophoto TerraItaly it2000 C.G.R. S.p.A. - Parma
LANDSLIDES & INFRASTRUCTURE Borsoi Landslide (BL) Veneto - october 2000
40000 35000 30000 25000 39070 20000 15000 10000 5000 0 HIGHWAY 693 ROAD RAILWAY 1754 URBAN AREA 14188 National Road SS134 Castelsardo (SS) Deformations of rail profiles in 1991 by Petacciato landslide (CB)
RISK ANALYSIS IN THE ITALIAN MUNICIPALITY The Attention level at the municipality scale is obtained overlapping the landslide layer and the vulnerable elements layer Very high, intersection with urban texture, industrial and commercial settlements; High, interference with lifelines, borrow pits, waste dump sites, construction works; Moderate, for farmed land, woods, urban green areas and playgrounds; Negligible, absence of landslide phenomena 5565 municipalities out of 8101 (69%) are affected by landslides Very high: 2820 municipalities Negligible: 2536 municipalities
LANDSLIDE HAZARDS COMMUNICATION Dissemination of information about landslides to national and local institutions and to the general public is a fundamental step in the successful mitigation of natural hazards. House destroyed by extremely rapid debris flow in october 2000 Messigny (AO) - Valle D Aosta
THE ITALIAN LANDSLIDE INVENTORY WEBSITE To provide internet access to geospatial information of the IFFI Project, APAT has designed the WebGIS application Cart@net-IFFI and the WMS Service of the IFFI Inventory. http://www.sinanet.apat.it/progettoiffi
SEARCH & IDENTIFY TOOLS Cancia debris flow Borca di Cadore (BL) Veneto Landslides identify: type of movement, degree of activity, damages, etc.
QUERY TOOL Landslide geographic research (i.e. for municipalities, Basin Authorities)
PHOTO TOOL Viewing photos of more important landslides
VIDEO TOOL
PRINTING LAYOUT
WEBGIS ARCHITECTURE SQL Server ArcIMS Map Server (vector data) Web Browser HTTP ECWP text text ArcSDE SINAnet Web Browser Web Server Cart@net-IFFI Image Web Server (raster data) HTTP Hypertext Transfer Protocol ECWP Enhanced Compressed Wavelet Protocol
THE IFFI PROJECT WMS (WEB MAP SERVICE) According to the European Directive INSPIRE 2007/2/CE (Infrastructure for spatial information in Europe) and the Open GIS Consortium specifications, WMS Services of the IFFI Inventory have also been developed. This interoperable Service allows the users to build a customized map overlaying the IFFI landslides theme with additional layers stored in the pc of the user or provided by different Internet map servers. IFFI Project WMS The user can access the WMS Service through a WMS viewer, as the one provided by the INSPIRE Geo-portal, or through a GIS Desktop
CONCLUSIONS The IFFI Inventory is an homogeneous and updated archive with a detailed spatial representation of landslides and it is an important tool for hazard and risk assessment and land use planning. Since 2005 the Inventory is available on the Internet with the aim of disseminating information about Italian landslides to stakeholders and citizens. To date over 200.000 hits have been counted on the IFFI Website. The WMS Service of IFFI Inventory allows an outstanding improvement in interoperability and data sharing between public administration, research institutes, geologists and engineers.
Agenzia per la protezione dell ambiente e per i servizi tecnici Dipartimento Difesa del Suolo Servizio geologico d Italia Organo Cartografico dello Stato Website: www.sinanet.apat.it/progettoiffi Contacts: alessandro.trigila@apat.it carla.iadanza@apat.it luca.guerrieri@apat.it