Automatic extraction of arrangement and optimal design of urban water network using by modern software (Case study: Torbat-e Heydarieh)

The cost of implementing water distribution networks, as one of the most important urban infrastructure projects, requires a huge investment. About 70% of the total cost of water distribution systems is directed to the cost of purchasing and implementation pipes. Reducing these costs requires choosing the right arrangement of pipes and choosing the correct diameter of network pipes from the available commercial diameters. Optimal design should be accompanied by the minimum cost of implementation and operation of the network without reducing the hydraulic performance according to the pressures and demands of the node. In order to optimally design the network to reduce the cost of investment and operation, several studies have been conducted. In these research, the initial plan is usually prepared, which is mainly done manually, taking into account all the available information, including topographic maps, urban toll maps, and population distribution and density. Then, using optimization methods, the optimal diameters are combined.However; the data needed to design a water distribution and wastewater collection network, especially in low-income countries, are often unavailable or of poor quality. Gathering the right data is often time-consuming and costly. On the other hand, the growth of modern technologies based on geographic information systems on the Internet such as Google Earth and OpenStreetMap, has made it possible to use the information in urban communication networks (such as passages, streets and roads) provided in the design of water distribution networks.On the other hand, the growth of modern technologies based on geographic information systems in the Internet such as Google Earth and OpenStreetMap, has made it possible to use information in urban communication networks (such as Passages, streets and roads) in the design of water distribution networks.Therefore, proposed an automated process for building models with the well-known EPANET tool. In this method, with limited input data and a few clicks, the user can create a network topology and assign the appropriate diameter of the pipe. For this purpose, a new program called WaterNetGen was designed and implemented as an add-on to EPANET software.As mentioned, the issue of optimal arrangement and composition of pipe diameters in water distribution networks is very important and efforts have always been made to facilitate its steps. The purpose of this study is the optimal design of water distribution network in zone 6 of Torbat-e Heydarieh in two stages completely without the intervention of expert opinions: in the first stage, the optimal network layout is extracted by DynaVIBe-Web system and then the optimal network design is minimized costs are made using WaterNetGen software. It should be noted that the proposed method has not been used in the country so far. Then, the results of the design with a completely software-based method are compared and evaluated with the current state of the network.

In this study, after receiving the initial design of the water distribution network of the case study from the DynaVIBe-Web system, , hydraulic constraints such as: nodes pressure and pipes velocity, pipes catalog … are added using by WaterNetGen software.Then, to continue the study process, 4 scenarios were considered as follows:S1: Existing status network of the city without any changesS2: Existing status network of the city with redesign using WaterNetGen software and pressure constraints based on the existing status network (in scenario S1)S3: Network extracted from DynaVIBe-Web system and designed using WaterNetGen software, pressure constraints based on existing state network (in scenario S1)S4: Network extracted from DynaVIBe-Web system and designed using WaterNetGen software, pressure constraints based on existing state network (in scenario S1)In the next step, the results of each scenario in different sections such as: velocity changes, pressure zoning, normal pressure distribution, excess pressure, length distribution and costs related to purchase and execution in all 4 scenarios are compared and finally the scenario Top was selected.

The results of this study show that the range of pressure and velocity did not change significantly. But in terms of purchase and implementation costs, the top scenario shows a 48% reduction in costs compared to the main network.

Finally, it can be said that by using the free web system DynaVIBe-Web and observing some common hydraulic conditions such as speed and pressure limits, using WaterNetGen software, a more efficient network design can be achieved than the main network of the city. Other benefits of this method include no need to use separate software to download satellite images and elevation lines to enter complex hydraulic software Water distribution network design such as WaterGEMS to draw network layout, save network design time, high accuracy in arranging the layout Network and optimal network design with observance of hydraulic constraints.