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 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 Network

1- Draw the Network by WaterCAD 2- Calculations using Excel to determine the growth rate

Population from Palestinian Central Bureau of Statistics YearPopulation numbers

Growth Rate Using Excel

Determination of Demand Assume The Demand =85 L/C-D Assume 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 Demand Number of houses=4 Demand= 4 *10*0.085=3.4 m3/day

Design Criteria 1- Velocities range (0.3 – 3) m/s. 2- Pressure head between (20-100)m.

Determination of Diameters Start with initial diameter =6 inches Run the Network by WaterCAD See the result of pressure and velocity Compare it with design criteria Change the diameter until satisfy the criteria

Value Of the Pressure

Value of Velocity

Design of Tank This method depends on the following assumptions : The expected number of persons in 2040 = The expected number of houses in 2040 = 24177/10 = 2418 Each 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 = (2418*1.5)= 500 m3

Design of Pump By 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) = m To determine Hp,use Bernoulli equation P 1 / ɣ +Z 1 +V 1 2 /2g + Hp= P 2 / ɣ +Z 2 +V 2 2 /2g + hl

Hp = ; 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 Pipeline In determine the pipe diameter we assume the following Assume diameter=6 in Applied continuity equation Q=V*A Q=140 m3/hour =.0388 m3/s V=0.0388/( π /4*(0.152))=2.13 m/s within the accepted limit ( ) m/s

Use Pressure Reducing Valve(PRV) Use pump in area close to the tank