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o To facilitate the process of providing consumers with clean water. o Provide quantity that suit their needs and control the quality of this water because

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oTo facilitate the process of providing consumers with clean water.

oProvide quantity that suit their needs and control the quality of this water because the presence of this network ensure unpolluted water and access to consumers with best quality.

•Design new WDN•Design a WDN to satisfy the future population growth.•Design a conveyance pipeline from the water supply to the village tank.

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Asira is located to north of the city Nablus, at a distance of 6

kilometers. It surrounds by Yassid, Bit-Mreen and Nesf-Jbeil for the

north, from the west the Sabastya and Ajnsnya villages, from east

Taluza and Wadi al-Bathan. Asira village overlook the southern

city of Nablus and the village of Iraq-Taieh. The village elevated

at about 650m about sea mean level. The Geographic coordinate

of the village is (x=175 Km, y =184 Km) according to the local

Palestinian grid.

o The climate of Asira Village is hot in summer and cool and rainy in winter, thus it does not have a big difference than that of Nablus City. The temperature of the air in the village is moderate; it has an average of 20.3 C.

Design of Water Distribution Design of Water Distribution NetworkNetwork

1- Draw the Network by WaterCAD

2- Calculations using Excel to determine the growth rate

Population from Palestinian Central Bureau of Statistics

Year Population numbers

1967 3217

1975 3620

1987 4568

1992 5090

1997 5724

2000 6421

2007 8200

2010 9675

Growth Rate Using ExcelGrowth Rate Using Excel

Determination of DemandDetermination of DemandAssume The Demand =85 L/C-DAssume the number of person in

each House =10 persons• Determine the expected number

of houses that each junction will serve , picture below will describe the procedure

Determination of DemandDetermination of DemandNumber of houses=4Demand= 4 *10*0.085=3.4

m3/day

Design CriteriaDesign Criteria1- Velocities range (0.3 – 3) m/s.

2- Pressure head between (20-100)m.

Determination of Determination of DiametersDiametersStart with initial diameter =6

inchesRun the Network by WaterCADSee the result of pressure and

velocityCompare it with design criteria Change the diameter until satisfy

the criteria

Value Of the Pressure Value Of the Pressure

Value of VelocityValue of Velocity

Design of TankDesign of TankThis method depends on the

following assumptions :The expected number of persons

in 2040 = 24177The expected number of houses

in 2040 = 24177/10 = 2418Each house has an average roof

tank volume = 1.5m3

The tank will provide the village two days

The demand of village = 2*.085*24177 = 4110 m3

The required volume of tank = 4110- (2418*1.5)= 500 m3

Design of PumpDesign of PumpBy applying Bernoulli equation between

the source and the tank:H1 + hp = H2 + hl , we will use The

Darcy-Weisbach equation is: = (.02*8467/0.152)* ((2.132)2/2*9.81) = 257.61 m To determine Hp ,use Bernoulli equationP1/ɣ+Z1+V1

2/2g + Hp= P2/ɣ+Z2+V22/2g

+ hl

Hp = 732.6 ; we take Hp =780m as factor of safety for minor loses

Required pump power = Where power in KW, Q: flow in

pipe (m3/s), hp: head added by pump, specific weight(N/m3)

Q in pipeline =0.38 m3 / s, Hp = 780m, water = 9810 N/m3

The required power = 396KW

Design of conveyance Design of conveyance PipelinePipelineIn determine the pipe diameter

we assume the followingAssume diameter=6 inApplied continuity equation

Q=V*AQ=140 m3/hour =.0388 m3/sV=0.0388/(π/4*(0.152))=2.13

m/s within the accepted limit (0.3 -3 ) m/s

Use Pressure Reducing Valve(PRV)

Use pump in area close to the tank