Introduction
The population growth of the cities in the world requires the perform of infrastructure works every day to guarantee the supply of clean and potable water to a population that needs every day more water for food, leisure, and living. But the supply water to human conglomerates has resulted in the removal of most of it, once it has been used and therefore contaminated.
The previous requires that the civil engineer took into account some elements that allow them through studies and specialized satisfy effective and sustainable manner the need to have water service, providing it uninterruptedly, in quantity and appropriate quality. The remoteness of supply sources and the scarcity of those supplies represent a challenge to all the professionals of the civil engineering, hydraulics, and urbanists responsible for the planning of urban centers (Eptisa, 2016).
The current document will study the infrastructure needs for a typical urban center related with the supply, management, treatment and extraction of served water with opportunity, quality, sustainable and cost effective. The different hydraulic infrastructures have specific functions that need to work integrated and not isolated. Each hydraulic infrastructure complements the rest of the system. The management of potable served and rainwater by two or more infrastructures. One of the infrastructures that fail will difficult the efficiency of the system and the quality life of the inhabitants of the considered urban center.
Methodology
The considered hydraulic infrastructure to be analyzed and studied is the following:
■ Potable water supply
■ Served water management (Sice, 2015)
■ Rain and stormwater flow and management.
■ Water treatment
■ Water wells
■ Required energy supply for water flow
The flow of water is analyzed under the fluid mechanic's principles, where the water is an incompressible material with an average density of 1000 kg/m3, a normal value of 20°C and an ebullition temperature of 100°C. The movement of water, kinetic energy, is due to the transformation of other source or energy as potential energy and mechanic energy. The potential energy is given by the height difference between the source and the drain. The Bernoulli equation (Equation 1) governs the movement of water in channels and pipes (Teyma, 2014).
H1 + V12/2g + W/(d*g) + f = H2 + V22/2g (Equation 1)
Today the general practice for water supply and extraction has prioritized the use of the potential energy to give kinetic energy to the water, due to the energy efficiency and to guarantee the total independence of the water system from the energy grid of the city.
With the previous technical principles, it is necessary to have the support of a specialist in hydraulics and engineering to develop criteria for a water management system for an urban center. A professional engineer in hydraulics, mechanics of infrastructure is the first person to consult for a design of a water management system because the professional have the necessary theory skills for the design. The second professional is a water plant operator; he may not have a university degree, but he has enough experience in the field giving to the study a realistic view of current designs concepts and recommendations of ideal water management systems (Rinne, 2005). Both professionals will go through an interview phase with the following questions:
Q1. What are the best design criteria for a water management system? Centralized or decentralized criteria?
Q2. With theory calculations of water flow. How much security factor it is necessary for the final design.
Q3. Is the water management system today able to protect the population of the virus and general diseases.
Q4. Is the "water table" a factor to consider in the flow in natural and constructed channels?
Q5. The treatment plant uses physical and chemical processes to clean the water?
Q6. The treated water is returned immediately to the city water system or the river?
Q7. How is it possible to have low electricity consumption for a water management system?
Results of Analysis
With the Equation 1 analysis, it is possible to confirm the necessity to use elevated water sources for the supply of water to the consumers of the urban centers. The use of elevated tanks by structures or mountains guarantees the water accumulation in periods of low consumption as night hours and the supply at a constant pressure without the generation of turbulences, very common in pipe systems connected to pumps. Figure 1 shows the recommended distribution using potential energy.
Figure 1: Water distribution plan with elevated water sources
The best criteria for the design of a water distribution system is to have a decentralized system where a client have one or two more sources, similar to a fire extinction system. In Figure 1, the shutdown of one water source does not affect the water flow to a specific client. A centralized configuration is very dangerous because it may limit the supply to one or all the clients if a centralized water source fails.
The design process of the water management system gives theory values of required heights, diameter pipes, energy consumption and other variables. It is necessary to work with a generous security factor for two reasons. The consumption growth of water and the equipment and pipe wear requires a security factor between 1.5 and 2.5 in the design process.
A water management system is a basic requirement to support the good health of the population. It is necessary to guarantee the potability of water to avoid stomach diseases in the population and the virus spread in the population. In fact, the access to potable water is a universal right. To guarantee potable water, the treatment plant must use a combination of physical and chemical processes to clean the water and return it to the river or the consumers. The physical process starts with the solid separation and use of electromagnetic filtration. After the physical process, the chemical process works with the combination of the treated water with chemical elements as chlorides, sulfates and other reactive. The treated water has technically the option to return to the consumer, but instead it is returned to the natural affluent or river and sea; the return of water is used in industrial processes, where there is no human consumption of water.
The use of electricity in the water management system is proportional to the volume quantity and the difference in the potential energy. The reduction of energy consumption is thanks to the use of new generation of pumps, low-resistance pipes and efficient consumption of the clients.
Discussion
The two professionals, one in the hydraulic infrastructure design and the second in the water treatment operation give a complete perspective about the required infrastructure of a water management system and what technology and operative conditions are necessary to have a successful water distribution system. The city must adapt the previous recommendations to its reality as the distance to the water source, water table depth, and consumers, current and future piping array.
Reference List
Eptisa. (2016). Hydraulic Infrastructure. Retrieved from Eptisa: http://www.eptisa.com/en/mercados/water-and-environment/hydraulic-infrastructure/
Rinne, K. W. (2005). Hydraulic Infrastructure and Urbanism in Early Modern Rome. Retrieved from University of Virginia: http://www3.iath.virginia.edu/waters/infrastructure.html
Sice. (2015). Hydraulic infrastructure. Retrieved from Sice: http://www.sice.com/en/lines-of-business/hydraulic-infrastructure
Teyma. (2014). Hydraulic Infrastructure. Retrieved from Teyma: http://www.teyma.com/web/en/actividades/construccion/hidraulica/
