This paper proposes a methodological approach to the re-use of reservoir sediments for coastal nourishment. The proposed approach represents a point of convergence between water and sediment management, coastal protection from erosion and the re-use of sediments dredged from reservoirs. In particular, this study indicates a general protocol of actions and a reference legislative scenario for the use of sediment from reservoirs for beach nourishment as an alternative to sediment from sea caves or land caves. Quantitative characterization of reservoir sediments and their qualitative characterization are the fundamental steps to define the compatibility between reservoir sediment and beach sand. The study was applied to a real case of Southern Italy known as the Guardialfiera Reservoir.

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Water loss is an issue that affect Water Distribution Systems (WDSs) very often, especially when aged and high pressure occurs. Pressure reduction valves (PRVs) can be used as devices to reduce as much as possible the water losses within the network. Indeed, for a given number of PRVs, the daily volume of water lost from the network can be reduced minimizing the pressure through a proper choice of valve positions as well as their settings. In this paper, a methodology for the optimal number, positioning and setting of PRVs is presented. In the proposed methodology, a genetic algorithm is coupled with a physical modelling of leakage from joints and a simplified and yet realistic hydraulic simulation of the WDS. The proposed methodology is demonstrated using two WDSs examples. Comparisons with a more extreme and complicated hydraulic modelling, already proposed by authors in previous work, are also performed in the first case study in order to validate the proposed methodology. These comparisons demonstrate that the methodology proposed in this work performs fairly well when compared to similar approach that uses a more sophisticated hydraulic model. As a consequence, it revealed to be a good tool for the optimal positioning and sizing of PRVs within WDS aimed at reducing the background leakages even when the WDS is characterized by complex geometry and topology

The work describes a procedure for the evaluation of the optimal number, positions, configuration and sizes of detention tanks inside urban drainage networks, aiming at containing expensive and troublesome replacement of existing sewers unable to properly convey runoff discharges. The procedure proposed is based on the use of a Genetic Algorithm (GA), in which the evaluation of the behaviour of each individual (i.e., of the entire drainage system, consisting of both the detention tanks inserted in it in place of one of a few existing sewer pipes and remaining existing sewers) is analyzed by a semi-distributed hydrological model, where the flood routing is carried out using a simplified hydraulic model: the kinematic wave approximation of De Saint-Venant equations. In particular, for each individual, the proposed hydraulic-hydrological model is used within a "variational" procedure, based on the evaluation, by varying the rainfall durations and the cor-responding value of the rainfall depths (whose correspondence is given by an intensity-duration-frequency relationship), of the maximum value of the peak discharges and/or flow depths. The pro-posed approach has been applied, for example, in a specific case study, showing its promising potential and its ability to obtain results of practical interest