Water Loss (WL) is a global issue. In Italy, for instance, WL reached 36.2% of the total fresh water conveyed in 2020. The maintenance of a water supply system is a strategic task that requires a huge amount of investment every year. In this work, we focused on the use of Distributed Fiber Optic Sensors (DFOS) based on Stimulated Brillouin Scattering (SBS) technology for monitoring water pipeline networks. We worked on High-Density Polyethylene (HDPE) pipes, today the most widely used for creating water pipelines. By winding and fixing the optic fiber cable on the pipe’s external surface, we verified the ability to detect strain related to pressure anomalies along a pipeline, e.g., those caused by water leakage. We performed two experimental phases. In the first one, we assessed the sensibility of sensor layout on an HDPE pipeline solicited with static pressure. We investigated the viscoelastic rheology of the material by calibrating and validating the parameters of a Burger model, in which Maxwell and Kelvin-Voigt models are connected in series. In the second experimental phase, instead, we focused on the detection of the pressure anomaly produced by leakage in a pipeline circuit set up with running water moved by a pump. The theoretical and experimental studies performed returned overall positive feedback on the use of DFOS for the monitoring of HDPE water pipelines. Future developments will be focused on more detailed studies of this monitoring solution and on the industrial production of “natively smart” HDPE pipes in which DFOS cables are integrated into the pipeline surface during the extrusion process.

We present a case study of a Structural Health Monitoring (SHM) hybrid system based on Brillouin Distributed Fiber Optic Sensors (D-FOS), Vibrating Wire (VW) extensometers and temperature probes for an existing historical water penstock bridge positioned in a mountain valley in Valle d’Aosta Region, Northwestern Italy. We assessed Brillouin D-FOS performances for this kind of infrastructure, characterized by a complex structural layout and located in a harsh environment. A comparison with the more traditional strain monitoring technology offered by VW strain gauges was performed. The D-FOS strain cable has been bonded to the concrete members using a polyurethane-base adhesive, ensuring a rigid strain transfer. The raw data from all sensors are interpolated on a unique general timestamp with hourly resolution. Strain data from D-FOS and VW strain gauges are then corrected from temperature effects and compared. Considering the inherent differences between the two monitoring technologies, results show a good overall matching between strain time series collected by D-FOS and VW sensors. Brillouin D-FOS proves to be a good solution in terms of performance and economic investment for SHM systems on complex infrastructures such as hydropower plants, which involve extensive geometry combined with the need for detailed and continuous strain monitoring.

Quantitative data on observed flood ground effects are precious information to assess current risk levels and to improve our capability to forecast future flood damage, with the final aim of defining effective prevention policies and checking their success. This paper presents the first collection and analysis of flood damage claims produced in Italy in the past 7 years since a homogeneous national procedure for damage recognition became available. The database currently contains more than 70,000 claims referring to significant events and shows good homogeneity on the intensity of the related phenomena. We then propose an empirical model, based on observed data, to allow for a quick estimation of direct damage to private assets (i.e., residential buildings), based only on the knowledge of the perimeter of the flooded area. Single model calibration was performed at the multi-regional scale, focused on southern Italy. Model validation shows encouraging performances, considering the considerable natural uncertainty that characterizes this type of estimate. The procedure is of great interest when there is a need to evaluate, however roughly, flood damage in the immediacy of the event to assess the extent of the flood effects and to plan support actions for the affected communities.

The problem of levee embankment control during high flows is crucial for flood risk management in floodplains. Levee defense lines are often hundreds of kilometers long and surveys during emergencies are not easy tasks. For these reasons, levees monitored with in situ sensors and a suitable Information Technology (IT) real-time data communication and integration infrastructure, so-called “smart levees”, are gaining increasing interest as a crucial protection technology in floodplains. The paper presents the conceptualization of a prototype of a levee smart revetment, based on the integration of an optical fiber (OF) cable into a steel double-twisted wire mesh. In this paper the feasibility of this kind of revetment is firstly assessed. The flow pattern of overtopping water on the embankment is discussed, thus producing a raw estimation of the shear stress acting on the revetment in the field. A sample case is then analyzed in both numerical and laboratory tests. For this purpose, a numerical Finite Element Model (FEM) to describe the mechanical behavior of a double-twisted wire mesh when loaded along its own plane is presented. Numerical results indicate that the related strain, relatively low as compared to the steel wire yield stress, can be fully detected by the optical fiber continuous Brillouin sensor. This has been validated by the experimental activity performed and a digital twin of the prototype of the smart revetment, suitable for virtually testing the product under any load and constraint conditions and tailoring the production process, has been created.

Smart levees represent a revolution in the field of embankment monitoring and safety during flood events. A smart levee, intended as the native (or “from scratch”) integration of an engineering structure with sensors and connection systems, provides detailed information on its past, current and future conditions Viz. integrity stress/strain conditions, maintenance state. This gives decision support to the figures in charge for maintenance and surveillance of the embankments, increasing efficiency and, particularly, the degree of protection from flood events. Sensor information can also be mashed up with other information, such as water stage, rainfall, soil wetness offering an useful integrated view of the river context.  We present here first results of a research project concerning the conceptualization of a sensing anti-erosion revetment for embankments, through the integration of a double-twisted steel wire mesh with an optic fiber cable. The fiber is woven  into the double-twisted sections and is capable to detect the nearly continuous deformation of the meshes caused by stresses exerted in its plane. The sensor sensitivity is enough to record deformation due to (small) shear stresses exerted by eventual overtopping flows, though it can bear (and report) huge deformations typical of quite higher stresses up to thousands of microstrain.  Several cycles of experiments, jointly with numerical modelling, clearly show the feasibility of such a product line, also showing a good linearity of the smart revetment behavior.

Each country has its own way to manage the civil protection issue and to define hazard and risk. However, in case of transboundary events, it is crucial that people in charge of the emergency management can quickly understand the other nation instruments, for an effective comprehension, communication and optimal collaboration.The GESTISCO project (Gestione delle emergenze Senza Confini – emergencies’ management without borders), funded in the framework of the “INTERREG Italia – Svizzera” initiative, aims to promote the capability of Lombardy Region (Italy) and the Ticino Canton (Switzerland) to manage risk scenarios involving both countries together. With this work, we present results of one of the project activities: to compare methods to define natural hazard and risk, understand and underline the differences in the mapping method and visualization, and find ways to help the operators and technicians of both countries in reading and interpreting the representations concerning flood and mass movements hazard.The activity began with a wide phase of comparison, undertaken from a legislative point of view, to understand the origin and purpose of the maps in both countries’ regulations. From a technical perspective, it was important to be aware of the differences in methods and to understand the reasons behind the inconsistencies. Finally, the data visualization on the maps was also compared, in order to understand the possible reading difficulties for people involved in the risk management and to identify strategies to overcome them.The next step of the project is the translation of the results of the performed analysis into some practical digital instruments that can easily allow to manage transboundary events, helping the operators in reading and understanding the scenario occurring across the border.