Water distribution system design

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  • 7/30/2019 Water distribution system design



    Submitted By:

    Saima 2010-Ba-1


    Submitted By:

    Saima 2010-BA-18

  • 7/30/2019 Water distribution system design


    Introduction of the scheme: No. of houses, flats & apartments: 935 Parks & open spaces: 8 Schools: 1 & Mosques: 2 Commercial Areas: 4 Graveyards: 3 Estimated area of scheme using scale factor of 1:10:82300m2 Design Criteria: Design Period: 20 years Sources of Water: Ground water Population Estimation: 10 persons per plot Design population: (No. of plots x population

    per plot) Per Capital Consumption: 350+47 =397 Peak Factor: 1.5 x MDD

    (maximum daily demand) Design Flow: Max. Hourly demand Type of Layout: Grid Iron (closed

    loop system) Type of supply: Continues Distribution system: pumping with


  • 7/30/2019 Water distribution system design


    Related Theory

    1.Water Consumptions:Water is one of basic need for humans. We fulfill our requirements using

    water. These requirements include drinking, bathing, washing, cooking (etc. atdomestic level &), running our machinery (at commercial or industrial level).

    2.Maximum Water Consumptions:This is usually taken as peak value that occurs once in a year, day or hour.

    So maximum water consumption is according to peak daily demand or peak hourlydemand.

    3.Peak Hourly Consumptions:It is amount of water consumed in an hour. It is a peak quantity. The peak

    consumption during any hour of the year excluding fire demand is called PeakHourly Consumption. It is around 150% of the maximum daily consumption.

    Factors Affecting Water Consumptions:Following are the factors that affect water consumptions:

  • 7/30/2019 Water distribution system design


    1.Climate:If the climate is warm then water consumption will be more. If climatetemperature is low then consumption will also be low. In other words thereis direct relation between these two quantities.

    2.Standard of Living:More advance standards of living will increase the consumption and viceversa.

    3.Water Metering:If the water consumption is measured properly i-e metering is doneproperly then consumption will be low and vice versa. In other words thereis an indirect relation between these two quantities.

    4.Quality of Water:High water quality will increase the daily water consumption. Low quality

    water will decrease consumption.

    5.Level of Services:Level of services will affect water consumption as follows:Stand post: Small communities collect water from a single source, this is calledstand post. It is very rare so consumption through this type of service has lowvalue.Yard connection: House collecting water from a single source, it is called yardconnection. This type of consumption has more value than yard connection.Full connection: it is mostly used now because water can be collected frommore than a single point in a house. This type of service provides more valueof water consumption.

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    6.Cost of Water:Greater cost of water will decrease the water consumption and vice versa.There is indirect relation between these two values.

    7.Type of Supply:Type of supply will affect the water as follows:Continuous: water supply is available at every time. Water consumption will bemore as compared to intermittent supply.Intermittent: water supply is available after sometimes.

    8.Pressure in Distribution System:Water pressure determines the force and speed of available water.1.Static pressure

    The amount of pressure within a system, pipes or hoses, when nowater is flowing.

    2.Normal Operating PressureThe amount of pressure within a distribution system during normalconsumption

    3.Residual PressureThe amount of pressure within a distribution system, at a given

    location (fire hydrant), when a substantial quantity of water is flowingsomewhere else in the system (at a major fire).

    Components of Water supply System:Following are the components of water supply system:


  • 7/30/2019 Water distribution system design


    It is point from water can be received. It can be underground source or surfacewater source.

    2.Transmission Lines:These are pipes used to supply water from source to storage tanks or pumps.These have different lifetimes depending upon material and use.

    3.Water Treatment Plant:A place or point where water is water is treated through disinfection andfiltration methods is called water treatment plant. It has the design period of10-15 years.

    4.Pumping Plant:This is a point where water is pumped from reservoir to storage tank ordistribution lines. It has the design period of 10 years. It has easy expansion.

    5.Storage:This is an important part of supply system. It stores water and in case ofincrease in water need or break in supply, it is used. It helps the water supplysystem in case of peak hourly demand.

    6.Distribution System:The system of pipelines used to supply water according to get requiresquantity and residual pressure.

    Methods of Water Distribution System:1.Pumping without Storage:This method is used where the supply is continues and the storage is

    not recquired. This method is also used in plain areas2.Distribution by Pumps with Storage:

    This method of distribution is used in plain areas where the type of supply isnot continues we mostly use pumping with storage.

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    3.Gravity Distribution System:This system is used for areas where altitudes are different. E.g. hillyareas we use distribution under gravity. This is not possible in plainareas

    -Results & CalculationCalculationsRegarding head loss in pipe lines taking consideration of all factors

    1-Break Horse Power of the motorBHP = Brake Horse Power1BHP = 1HPBHP = *Q*H/550* = density of water = 62.4 lb./ft3 = 999.47 kg / m3Q = Flow through pump = 0.019 m3 / secH = Total Pump Head = 245 m = Efficiency of Motor = 60% = 0.6BHP = 999.47 0.019 245 / 550 0.6BHP = 5.07 HP

    2-Head loss calculationsTotal Pump Head = Difference in level between tube-well and OHR +losses in pipe (H) + losses in pump chamber (4.57 m)+ height of OHT (20m) + Drawdown of tube-well (9.14 m) + safe head (4.57 m)Losses in pipe (H) = 10.68 * (Q/c)1.85 * [L/(d4.87)]

    = 10.68 * (39.78* 10-3/100)1.85 * [100/(0.34.87)]= 0.019mTotal Pump Head = 0+0.019+4.572+20+9.144+4.572+213.36Total Pump Head = 245 m


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    Table for calculation of base demand Representation Of Results in table form output file

    (EPA.NET) Attachment of Maps using EPA.NET (which represents

    pressure values at node and diameters values at pipes) Attachment of Map (Manual)

    -Recommendations & References https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=we


    http://en.wikipedia.org/wiki/Drinking_water https://www.google.com/#hl=en&sclient=psy-