Luigia Brandimarte

Analysis of fresh-saline water interface at the Shatt Al-Arab estuary

ABSTRACT The river formed by the confluence of the Tigris and Euphrates is known as the Shatt Al-Arab; it runs for about 190 km from the confluence of the Tigris and Euphrates, in Qurnah, Iraq, to the Arabian/Persian Gulf. The lowest alluvial plains of the Tigris and Euphrates have been for millennia exploited for their fertile soils and rich date palm forest. Nevertheless, over the past decades, this productive region has experienced the negative impact of salt intrusion from the Gulf, jeopardizing the environment and the economy of the region. The causes of salt intrusion in the Shatt Al-Arab have be ascribed to anthropogenic activities in the area, such as, for example, damming of the Tigris and Euphrates, which induced new flow regimes in the Shatt Al-Arab. Although modelling salinity intrusion has become a common practice in research and applications, availability of input data might have discouraged or limited the analysis of salinity intrusion in the Shatt Al-Arab. The kind cooperation of the Center of Study and Design at the Ministry of Water Resources of Iraq made it possible to collect relevant and valuable data for the development of this research work which aimed at understanding the behaviour of salt intrusion in the Shatt Al-Arab in relation to the inflow conditions in the Tigris and Euphrates rivers. A scenario analysis approach was adopted for investigating the relationship between salt intrusion and different inflow conditions in the Tigris and Euphrates rivers.

Innovative Probabilistic Methodology for Evaluating the Reliability of Discrete Levee Reaches Owing to Piping

AbstractTraditionally, levees are a popular measure widely adopted for flood control, accepted and trusted by populations living in floodplain areas. The presence of levees sometimes might even induce a false sense of safety in the population, influencing their decision to develop further in floodplains, because they feel safer. Thus, failures of levee systems are potentially devastating, as they might induce loss of human lives, damages to properties, and economic loss. This study proposes an innovative methodology to estimate the reliability of levee systems, accounting for different sources of uncertainty, and to divide and classify discrete levee reaches, according to different fragility classes. The reliability analysis is performed by evaluating the probability of failure, as a function of a certain failure mechanism, conditioned by a given hydraulic load. Fragility curves are determined using two different methods: Monte Carlo data generation and the so-called approximate, first-order reliability m...

Effects of climate change over energy production in La Plata Basin

The population growth and the economic development that the five Countries (Argentina, Bolivia, Brazil, Paraguay and Uruguay) located in La Plata Basin (LPB) have gone through over the last decades have risen the necessity to assess the current and future electricity demand and compare it to the energy production. In this region, the water resources of LPB are one of the most important sources of energy. In this context, the CLARIS EU (European Union) FP7 project has carried out an extensive research work which, in terms of investigating hydropower potential and vulnerability, has produced the following outcomes: assessment of current hydropower production and electricity demand; calculation of the maximum potential hydropower in order to establish whether and when shortage in terms of hydropower generation is to be expected; analysis of potential residual hydropower taking into account future user demands and analysis of hydropower production taking into account climate change scenarios, in order to identify potential vulnerabilities under variable input and/or needs for other sources of energy. This paper focuses on the outcomes of the climate change scenario analysis and its impacts on hydropower production in the basin. This has been investigated by (1) assessing the current hydropower production and electricity demand over the last 20 years (1991–2010), in order to establish growing trends in the short-term (2031–2040) and at the end of the century (2079–2098); (2) estimating maximum potential hydropower under present hydrological conditions; (3) analysis of potential vulnerability, by combining the first two research steps and (4) analysing the impact of climate change scenarios on hydrological variability and thus on hydropower production. The assessment of hydropower production and electricity demand determined that the current hydropower production represents about 73% of the electricity demand. Analysing the trends for the electricity produced by hydro-plants and the electricity demand, it is evident that the increment rate for the hydroelectricity production is lower than the increment rate of the electricity demand. Although, the maximum theoretically available energy at the basin level is about 683 GWh, the maximum feasible available energy (taking into account environmental flow requirements and financial constraints) will be of about 514 GWh per year. The climate change analysis shows an opposite trend at the sub-basin level, but overall, at the basin scale, the hydropower production is expected to increase because of changes in the hydrological variables.

Effects of levee cover strength on flood mapping in the case of levee breach due to overtopping

ABSTRACT The reliability of a levee system is a crucial factor in flood risk management. In this study we present a probabilistic methodology to assess the effects of levee cover strength on levee failure probability, triggering time, flood propagation and consequent impacts on population and assets. A method for determining fragility curves is used in combination with the results of a one-dimensional hydrodynamic model to estimate the conditional probability of levee failure in each river section. Then, a levee breach model is applied to calculate the possible flood hydrographs, and for each breach scenario a two-dimensional hydrodynamic model is used to estimate flood hazard (flood extent and timing, maximum water depths) and flood impacts (economic damage and affected population) in the areas at risk along the river reach. We show an application for levee overtopping and different flood scenarios for a 98 km reach of the lower Po River in Italy. The results show how different design solutions for the levee cover can influence the probability of levee failure and the consequent flood scenarios. In particular, good grass cover strength can significantly delay levee failure and reduce maximum flood depths in the flood-prone areas, thus helping the implementation of flood risk management actions. EDITOR D. Koutsoyiannis ASSOCIATE EDITOR A. Viglione