at 13H30 | 520 BE

Sustainable Management of Water Networks

Moderated by: Serge Cyr, Ville de Victoriaville
Sustainable cities

- Watermain Condition Assessment : What are we looking for and how much are we willing to pay?

This conference will present different condition assessment tools for watermains and the level of information each can provide to a municipality, and at what cost. Apart from the direct inspections costs, there are indirect costs for the preparation of the network that the municipality has to bear before the inspection.The tools that will be presented will be of the non-destructive variety that are currently being used in North America. They range from intrusive leak detection and visuals (for small and large diameter), as well as pipe wall thickness measurements using acoustic, electromagnetic and ultrasound technologies.For smaller diameter pipes up to 300mm (12-in), the tools used can be inserted through an existing fire hydrant or a small tap on the pipe. For larger diameter pipes, preparation work will be required to insert the different tools.

- CFD Modelling to ensure the quality of drinking water in distribution reservoirs

The City of Montreal has been developing their expertise in computational fluid dynamics (CFD) modelling in order to guide the rehabilitation works of its main drinking water storage facilities. The purpose of these models is to ensure the quality of the stored water by simulating the water ageing process which is related to water quality. The methodology of these models was validated by a tracer study which was carried out on an initial reservoir. The comparison between modelled and measured residence time distribution validates this approach. Based on this achievement, the same methodology was applied on one of the main reservoirs of the City of Montreal. These numerical models highlight a situation which was unknown by the operators, and then allowed them to take a simple corrective action. Now, this expertise in CFD modelling is used for all the reservoirs of the City of Montreal and results in the solution of complex hydraulic problems.

- Pressure Management in Water Distribution Systems: Evaluation of the Benefits of Various Control Modes

Several solutions for pressure management are proposed by IWA in order to respond to the objectives of reducing water losses in water distribution systems (WDSs). One of the recommended solutions is to continuously adjust the pressure settings of pressure reducing valves (PRVs). These valves offer the possibility of operating the WDSs according to one of the following control modes: i) fixed control; (ii) time-based control; iii) reactive real-time control; and (iv) predictive real-time control. The evaluation of the performance of the different pressure control modes was carried out by hydraulic modeling for a few sectors of Canadian WDSs. The comparison between the performances of the various pressure control modes was based on the potential benefits in terms of leakage rate reduction, for different network characteristics.