Carlo Ciaponi

Simplified Procedure for Water Distribution Networks Reliability Assessment

This work describes a simple procedure for the analysis of water distribution system (WDS) performance. It is based on the reliability assessment of a WDS during failure states resulting from the unavailability of a pipe (maintenance or repair), taking into account the probability of the failure events. The procedure may consider changes in daily demand by using patterns defined to represent seasonal trends. Applying this method to a network with around 200 pipes demonstrates its usefulness, especially when the aim is to objectively compare different design solutions. The procedure takes also into account variations in design parameters such as an increase in water demand and/or a drop in hydraulic conductance resulting from pipe lining degradations (corrosion or deposits). DOI: 10.1061/(ASCE)WR.1943- 5452.0000184.

Procedure for Defining a Pressure-Outflow Relationship Regarding Indoor Demands in Pressure-Driven Analysis of Water Distribution Networks

The definition of the relationship between the actual flow delivered by a node of a water distribution network and the available nodal pressure head is one of most crucial problems in Pressure Driven Analysis (PDA). The paper proposes a procedure, based on two models (building model and supplied urban area model), by means of which it is possible to generate and to simulate numerous different scenarios regarding the water delivery in the urban area supplied by a distribution network node. The scenarios are achieved by reproducing, through appropriate random generators, several urban and hydraulic situations, which are defined by various parameters governing water delivery. The statistical processing of the simulation results allows to define a representative pressure-flow relationship which reproduces, on average, the complex and varied set of phenomena governing the actual water delivery. Two application examples are also presented; the results of these study cases allow to calibrate the Tanyimboh and Templeman (2010) relationship, which is good for incorporation in PDA algorithms, because it is continuous with its first order derivatives in the whole field of pressure head values.

Sampling Significant Contamination Events for Optimal Sensor Placement in Water Distribution Systems

AbstractThis paper presents a procedure for sampling the most representative contamination events in the framework of optimal sensor placement with two objective functions to be minimized, namely, ...

Placement Strategies and Cumulative Effects of Wet-weather Control Practices for Intermunicipal Sewerage Systems

This study investigates the rainfall-runoff process and the pollutant dynamics on theoretical catchments and intermunicipal sewer systems in order to characterize the hydraulic and environmental performance of possible types of sewerage system and to compare the effectiveness of different wet-weather control schemes for intermunicipal sewerage systems. A comprehensive investigation on the placement strategies and the cumulative effects of wet-weather control practices is carried out over a broad watershed as a key preliminary step in addressing surface water safeguard requirements in developing and urban areas. The analysis shows that the different types of intermunicipal sewer system exhibit slightly different performance. Placing wet-weather detention tanks at different spatial levels affects the overall effectiveness of the wet-weather control system. In the examined case study schemes, the insertion of a wet-weather detention tank is better on final than on local flow regulators. The performance control also proves to be easier adopting the solution with intermunicipal tank since, for this scheme, the design criteria have a more important influence than rainfall characteristics on the environmental performance. These results represent an issue of primary focus for the implementation of environmental policies and mitigation strategies against surface water impairment in urban and developing areas.

Modularity-Based Procedure for Partitioning Water Distribution Systems into Independent Districts

A proper division of a Water Distribution System (WDS) into District Metered Areas (DMAs) provides important management benefits particularly with regard to leakage detection through water balances, control and optimization of pressure so as to reduce leakage, implementation of monitoring, warning and emergency acting systems against accidental or intentional water contamination. This paper presents a new methodology that combines a suitable modularity-based algorithm for the automated creation of DMA boundaries and convincing practical criteria for the DMA design. A further plus of the proposed methodology is its ability to identify many technically feasible solutions that can be subsequently economically assessed. The successful applications of the proposed methodology to a real case study, already tested by other authors, has proven its effectiveness for the DMA design in existing water distribution systems.