Massimiliano Cannata

Two-dimensional dam break flooding simulation: a GIS-embedded approach

In the twenty-first century, around 200 notable dam and reservoir failures happened worldwide causing massive fatalities and economic costs. In order to reduce the losses, managers usually define mitigation strategies identifying flooding area due to dam break by using standalone hydrodynamic models and then importing the results within a GIS to perform risk analysis. This two-step procedure is time expensive, error prone due to export/import requirements and not user friendly. For this reason with this work, a new numerical model for the solution of the two-dimensional dam break problem has been implemented in the GRASS GIS with a GIS-embedded approach. The model solves the conservative form of the 2D shallow water equations using a finite volume method; the intercell flux is computed by one-side upwind conservative scheme extended to a two-dimensional problem. The newly developed GIS module, among others outputs, allows to derive maximum intensity maps that can be directly used for risk assessment. Finally, the model has been (1) tested against two standard synthetic problems referenced in literature showing differences in estimated water depth of 2, 3 and 15% and (2) verified against official flooding map of an existing dam (Verzasca) detecting 75% of similarity. The problem formulation, the new GRASS module and its validation is presented.

Digital terrain model reconstruction in urban areas from airborne laser scanning data: the method and an example for Pavia (northern Italy)

Light detection and ranging (LIDAR) techniques represent a new and fruitful approach in the determination of digital surface models. One of the goals in processing this data is to set up filtering methods which automatically allows to extract the ground and the features (buildings, vegetation, etc.) superimposed on the terrain itself. In our work the emphasis is focused on the first topic. The implemented method takes advantage of the use of spline functions regularised by means of Tychonov functional in a least-squares approach. Firstly, the DSM pixels have been classified in order to previously detect any edges of the non-terrain feature. Then all the pixels corresponding to the ground, by means of a region growing algorithm, has been identified through a correction procedure. Finally, by a new interpolation on the classified ground pixel only, we can derive the digital terrain model. In the paper the processing methodology is discussed; and a first extensive example is presented.

Modeling of Landslide-Generated Tsunamis with GRASS

The following research aims to enhance and spread the capacity of assessing risk due to landslide-generated tsunamis by fostering the use of a GIS (Geographic Information System), and in this particular instance, an Open Source GIS (where “Open Source” can be loosely defined as freely available source code). For this purpose, we tested a procedure to be spatially implemented in the Open Source GRASS GIS through developing a module named r.impact.tsunami that simulates landslide-generated tsunami. In this article we present its application in a case study performed on Como Lake (Lago di Como) in northern Italy. The review of the results identified sources of uncertainties while the model sensitivity outlined the influence of the parameters governing the model. Moreover, in order to verify the model validity, we implemented a new module (r.swe), that simulates the tsunami propagation and run-up with the shallow water equations, and compared the results. Notwithstanding non-negligible differences, the two models produced results of the same magnitude; this confirmed the validity of both models, although a rigorous validation of the models could not be performed due to the lack of observed data.

istSOS, a new sensor observation management system: software architecture and a real-case application for flood protection

istSOS (Istituto scienze della Terra Sensor Observation Service) is an implementation of the Sensor Observation Service (SOS) standard from the Open Geospatial Consortium. The development of istSOS started in 2009 in order to provide a simple implementation of the SOS for the management, provision and integration of hydro-meteorological data collected in Canton Ticino (Southern Switzerland). istSOS is an Open Source, entirely written in Python and based on reliable software like PostgreSQL/PostGIS and Apache/mod_wsgi. This paper illustrates the latest software enhancements, including a RESTful Web service and a Web-based graphical user interface, which enable a better and simplified interaction with measurements and SOS service settings. The robustness of the implemented solution has been validated in a real-case application: the Verbano Lake Early Warning System. In this application, near real-time data have to be exchanged by inter-regional partners and used in a hydrological model for lake level forecasting and flooding hazard assessment. This system is linked with a dedicated geoportal used by the civil protection for the management, alert and protection of the population and the assets of the Locarno area. Practical considerations, technical issues and foreseen improvements are presented and discussed.

Software tools for sustainable water resources management: the GIS-integrated FREEWAT platform

This paper aims at presenting the open source and public domain FREEWAT platform capabilities for water resource management, including: (i) pre-processing modules to facilitate the preparation of input data, (ii) modelling tools for the analysis of several processes aimed at supporting water resource management, and (iii) post-processing tools to present results.The FREEWAT platform is based on open source solutions to perform an integrated coupling between the QGIS desktop software, surface and subsurface model engines, mostly based on fully distributed and numerically-based codes developed by the USGS, and other software applications, and the SpatiaLite spatial database. The development of the FREEWAT platform was supported by the main needs and priorities expressed by relevant stakeholders from the water sector involved in the early stage of the project.Extensive testing on the platform is still going on and training material and six User Manuals were prepared to disseminate its use as a standard software for managing surface/sub-surface water quantity and quality dynamics under demand-driven and supply-constrained conditions. The testing phase also includes demonstration of the platform capabilities on 14 case studies at European scale and beyond, to address specific water management issues. Nine of them are devoted to the application of EU water-related Directives, while the others address water management issues in the rural environment under the requirements of EU and/or national/local regulations. Beyond software testing, this demonstration is thought as an experiment on involving stakeholders in the formation of water plans yet during the technical phase of the analysis.

FREEWAT, a Free and Open Source, GIS-Integrated, Hydrological Modeling Platform: L. Foglia et al. Groundwater XX, no. X: XX-XX

Author(s): Foglia, Laura; Borsi, Iacopo; Mehl, Steffen; De Filippis, Giovanna; Cannata, Massimiliano; Vasquez-SuA±e, Enric; Criollo, Rotman; Rossetto, Rudy

GIS-based Calibration of MassMov2D

34 Pags., 3 Tabls., 9 Figs. The definitive version is available at: http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1467-9671

Open source GIS platform for water resource modelling: FREEWAT approach in the Lugano Lake

The FREEWAT platform is an innovative Free and Open Source water resource modelling platform integrated in the QGIS geospatial software, using the SpatiaLite database, and including globally-established simulation codes from the USGS MODFLOW models family. This paper demonstrates its application to the Lugano Lake basin case study, Switzerland and Italy. Two specific modules of the platform were used to execute data integration and analyses: the Observation Analysis Tool and the Lake Package. The first one is a newly developed module facilitating the integration of time-series observations into modelling by enabling pre- and post-processing in the model environment; the latter is an existing MODFLOW package allowing dynamic evaluation of groundwater/lakes interaction. In the case study implementation, a participatory approach was adopted to enhance trust and acceptance of results. These show that integration of simulation codes within GIS is highly appreciated. Furthermore, its openness and freeness allow easily sharing of developed analysis and models. Stakeholders also positively evaluated the participatory process as it empowers decision making with a better understanding of model results and uncertainties. The combination of the FREEWAT platform and the participatory approach may constitute a valuable methodology to include scientifically based analysis to be used for policy design and implementation.

Integrating free and open source tools and distributed modelling codes in GIS environment for data-based groundwater management

Abstract Integrating advanced simulation techniques and data analysis tools in a freeware Geographic Information System (GIS) provides a valuable contribution to the management of conjunctive use of groundwater (the worlds largest freshwater resource) and surface-water. To this aim, we describe here the FREEWAT (FREE and open source software tools for WATer resource management) platform. FREEWAT is a free and open source, QGIS-integrated interface for planning and management of water resources, with specific attention to groundwater. The FREEWAT platform couples the power of GIS geo-processing and post-processing tools in spatial data analysis with that of process-based simulation models. The FREEWAT environment allows storage of large spatial datasets, data management and visualization, and running of several distributed modelling codes (mainly belonging to the MODFLOW family). It simulates hydrologic and transport processes, and provides a database framework and visualization capabilities for hydrochemical analysis. Examples of real case study applications are provided.

Open technologies for monitoring systems aimed at disaster risk reduction

This research is spearheading the integration of Free and Open Source Software (FOSS) and Open Source Hardware (OSHW) in the field of agri-meteorology applications to disaster risk reduction, flood and droughts. A Do-It-Yourself weather station based on OSHW standards has been developed from local sources in Sri Lanka, reporting by SMS to tank/reservoir managers when rainfall is higher than 10mm/h. These weather stations are soon going to be reprogrammed to report to istSOS, a FOSS web-based Sensor-Observation-Service compliant system, which will collate live reporting of rainfall every hour and before if intensities are dimmed worrying for flood risks. This is both a scientific, technological, and practical challenge toward a very low cost real time disaster risk notification system in places where climate, economy and maintenance supports are themselves other challenges.