Design Period

Water Supply SystemENG:MUSTAFA ABOU FOUL1

Contents2Project TitleProject: Design and analysis of water supply system of Gaza city.The aim and objective of the project is to supply safe water for the cheapest cost for all areas of Gaza city.

Water Supply System ( ) - .

3Main ObjectivesThe main objectives of water transport and distribution systems are common:supply of adequate water quantities,maintaining the water quality achieved by the water treatment processEach of these objectives should be satisfied for all consumers at any moment and at acceptable cost.Speaking in hydraulic terms, sufficient quantity and quality of water can be maintained by adequate pressure and velocity.

4Main ObjectivesConsidering the engineering aspects, the quantity and quality requirements are met by making proper choices in the selection of components and materials.5 : ( ..) (Flow Rate Q) . . Main Objectives . . . . .

6Water Supply System (Water Supply System) : (Water Source) ( ). (). ( ). ( ). ( ). .7 (2)Transport SystemDistribution Network SystemWater Supply System = Transport + Distribution NetworkWater Supply System Processes

8 In general, a water supply system comprises the following processes:raw water extraction and transport.water treatment and storage.clear water transport and distribution.123 (1)Water Treatment

9 (2)Sources of Potable Water Untreated water (also called raw water) may come from:Groundwater Sources such as wells.surface waters such as lakes, reservoirs, and rivers. The raw water is usually transported to a water treatment plant, where it is processed to produce treated water (also known as potable or finished water). 10

Water Situation in Gaza Strip . 317 /. ( ). 110 . (110) .

11Water Situation in Gaza Strip 40 % ( 2005 ) 45 /. () .12Water Situation in Gaza Strip . 160 2006 110 50 .13

14General Steps of Network Design : : ( ) (Preliminary Studies) : . . . ( ).15General Steps of Network Design : . ( ) (Pattern Curve). .

16General Steps of Network Design : (Network Layout) (Wells, Pumps, Pipes, Valves, Tanks)17 : (Hydraulic Analysis) ( ) .General Steps of Network Design - - .18 : . . ( ). . ( : )General Steps of Network Design ( ) . . . . . : 19General Steps of Network Design . ( ).

20 : . .Population forecastingLecture 1Design Period22Technical Lifetime : It represents the period during which it operates satisfactorily in a technical sense. The suggested periods for the main distribution system components shown in the following table :

ComponentPeriod ( Years )Transmission main30 - 50Distribution main30 - 100Reservoirs20 - 80Pumping station - facilities20 - 80Pumping station - equipment15 - 30Technical ConcernsEconomical ConcernsEstimation of design period23

Estimation of population24 1% 7% 3% 6% 4.5% 6%. 2.5% :

Population forecasting25

Arithmetic increase method This method assume that the population density increase uniformly Population after time tPresent population

population growth rate by each t unitThis equation can be simplified to: Uniform percentages Method Predicted curves Method (curvilinear method)

population growth rate by each t unitpopulation growth rate by each t unit26Example27Estimate the population number after 30 year, if the initial population number is 100,000. the population growth rate is 3%

Method 1Method 2Method 3

Population Saturation and urban planning28Master PlaneLand-UseGeneral lawsAlthough the population forecasting methods gives the population at the end of the design period, the maximum possible population is also estimated according to the number of apartment and stories per unit area and the maximum family members.

The Saturation population can be determined using the Master plan for the area and its general laws.

The minimum of the two values is taken in consideration when the network is designed.

Example29A residential area 100,000 m and population of 4200 capita has the following Master Plan : 25 % of the total area is for Streets. 5 % of the total area is for green Areas. 70 % of the total area is for buildings. 60 % of the building area is for building. If the family living there consists of members and the average apartment area is 150 m, Calculate the Population needed for designing a water distribution system to serve that area for 25 years if you are given that the growth rate of the population = 3 %.

Cont. example301. Population Forecasting : Pt = P0 (1+k)n Pt = 4200 (1+0.03)25 Pt = 8794 capita Saturation Population :

The Population = 7000 capita

0.7 100,000 = 70,000 Total Building Area (m)0.6 70,000 = 42,000Building Area (m)42,000 5 = 210,0005 Stories Building Area210,000 / 150 =1400No. of Apartments1,400 5 = 7000 capitaSaturation PopulationArea Study

Residential AreaPublic AreaCommercial AreaAgricultural AreaStreets

%Area (m2)Item100641 DuonmTotal Area81519,917Residential Area319,230Public Area425,640Commercial Area212,820Agricultural Area638,460Industrial Area425,640Streets Population DensityCalculation of total number of residents:Normal Increase ( using equations)

Example:- Total Area of Southern Remal = 2,754 DounmTotal population in Southern Remal in 2002 = 17,500Total population in Southern Remal in 2008 = 29,300

Statistical DataHypothetical figures Continue..Population in Area under consideration:

Population DensitySaturation populationTotal Residential Area = 519,917 m2

Total number of population under saturation condition = 45,721 + 59,918 = 105,639

Towers (6 floors and more)Regular Buildings (5 floors or less)149,795370,122Area83Avg. no. of floors140170Avg. area of flats (m2)(149,795/140) x 8(370,122/170) x 3# of flats77Avg. no. of persons/flat59,91845,721No. of residentsPopulation DensityTherefore,

Population density= Population / Total Area = 99,435 / 641,000 = 0.155 person/m2

ReferencesAl-afifi, Ayman. Lecture Notes. Islamic University of Gaza, 2009.Khaleel, Alastal. Lecture Notes. Islamic University of Gaza, 2006. Mohammed Alhissy Lecture Notes. Islamic University of Gaza, 2010.Trifunovi, Nemanja. Introduction to Urban Water Distribution. Taylor&Francis Group, London 2006.37