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The paper presents the analysis of the water distribution system of the town of Chiaravalle, in Central Italy. A hydraulic model of the network is implemented and calibrated to improve the system management. Besides the possibility of reducing the service pressure by inserting some pressure reducing valves, the economic convenience of coupling the valves with the pumps as turbines to covert energy dissipation in energy production is investigated. The determination of the number, location, and setting of such valves and machines are described together with the effects of the pressure control. [ABSTRACT FROM AUTHOR]

• Flood emergency in Historic Built Environments (HBEs) is investigated. • Typical HBEs are defined on case-studies data classification. • Hydrodynamics and pedestrian evacuation simulations are performed on them. • Results are organized in risk indexes with and without pedestrian evacuation behaviors. • Risk differences with and without pedestrian evacuation behaviors are noticed in each outdoor space in the HBE. Riverine Historic Built Environments (HBEs) in urban centres are relevant scenarios for flood risk, due to the compact layout of their outdoor spaces, that are squares and streets, and their position in flood-prone areas. Differences in HBE layout can provide differences in flood risks, but excluding the response of exposed individuals can lead to risk underestimation or overestimation, as for other hazards. This work is a first attempt to compare how accounting or not pedestrian evacuation behaviours can affect flood risk assessment and emergency strategies evaluation. Parametric configurations of typical HBEs are provided on case-studies, and existing tools for hydrodynamic and pedestrian evacuation simulation are applied to them. Risk indexes for the whole HBE (macroscale) and each outdoor space (microscale) in it are provided. Results show how the risk indexes trends accounting or not pedestrian evacuation behaviours are similar if considering the macroscale, while differences at the microscale exist (about 15 % in absolute terms). Concerning emergency strategies, sheltering seems to decrease the risk for the whole HBE up to 33 % in comparison to leaving the flood-affected area. Results also support where/how to place gathering areas in the HBE. [ABSTRACT FROM AUTHOR]

• Accelerated aging methods for PE pipes exposed to ClO2 are described and discussed. • The main factors affecting the degradation mechanisms of PE pipes are identified. • Optimal pressurized pipe loop methods are identified in the closest tests. • Operating conditions for accelerated aging of PE pipes are proposed. Polyethylene (PE) pipes have been widely used in drinking water distribution systems across the world. In many cases, chlorine dioxide (ClO 2) is used to maintain a residual disinfectant concentration in potable water. Practical experiences have shown that the lifetime of PE pipes is significantly reduced due to exposure to drinking water with ClO 2. Recently, many companies have proposed new PE pipes with a modified formulation, which are more resistant to chlorine dioxide. However, a standardized test method for evaluating the long-term performances of PE pipes is still missing. This literature review was performed to provide a description of chlorine dioxide uses and degradation mechanisms of polyethylene pipes in real water distribution systems. Current accelerated aging methods to evaluate long-term performances of PE pipes exposed to ClO 2 are described and discussed along with the common technics used to characterize the specimens. Accelerate aging methods can be distinguished in immersion aging tests and pressurized pipe loop tests. Wide ranges of operational conditions (chlorine dioxide concentration, water pressure, water temperature, etc.) are applied, resulting in a great variety of results. It was concluded that pressurized looping tests applying semi-realistic operational conditions could better replicate the aging mechanisms occurring in service. Despite this, the acceleration and the evaluation of the long-term performance are still difficult to determine precisely. Further experimentation is needed to correlate chemical-mechanical characterization parameters of PE pipes with their lifetime in service. [Display omitted] [ABSTRACT FROM AUTHOR]