fairness water distribution at on- farm irrigation...

Nineteenth International Water Technology Conference, IWTC19 Sharm ElSheikh, 21-23 April 2016

194

FAIRNESS WATER DISTRIBUTION AT ON- FARM IRRIGATION

DEVELOPMENT PROJECTS IN EGYPT: CASE OF VARIABLE LAND LEVELS

Hany G. Radwan

Assistant professor, Irrigation and Hydraulics Department, Faculty of Engineering, Cairo University,

Giza, Egypt. Email: [email protected]

ABSTRACT

Water is a critical component of development in Egypt. 79% of the cultivated lands in Egypt are

considered old lands which are irrigated using traditional on-Farm Distribution System (FDS). FDS

refers to a network of small channels which usually serves areas ranging from 10 to 500 feddan with a

full responsibility by the farmers. Farm ditches serving plots belonging to usually more than one

farmer are called Mesqas which branched into small distributed ditches called Marwas. FDS at old

lands in Egypt contributes with about 40 to 60% of the total irrigation system losses. So, improved

irrigation projects in Egypt came to overcome this problem through increasing the irrigation

efficiency, and to enhance the quality of irrigated water at on-farm level by converting the earth cross

section of Mesqa, and Marwa channel into low pressure pipeline system. The main objective of this

paper is to detect the required operational conditions to achieve equity water distribution between

beneficiaries to achieve full satisfaction between farmers. An accepted and allowable limits for the

concept of equity water distribution are established with allowable difference in the discharge between

opened hydrants with four limits 5%, 10%, 15%, and 20%. This paper discuss the required operational

conditions to achieve equity water distribution between hydrants in case of varied land levels. Through

this paper, the critical downward slope for achieving exactly equal water distribution regardless of the

distance between opened hydrants has been determined. Such these slopes can be achieved during the

implementation of imbedded pipelines. Also the maximum distance between opened hydrants is

determined for random land slopes (upward, downward slopes) for achieving specified difference in

the discharge. Finally, this paper provides standard graphs and tables which can be used to achieve

equity water distribution between beneficiaries at on-farm distribution system.

Keywords : Irrigation System; Improved irrigation projects; Fairness water distribution, on-farm

Irrigation.

1. INTRODUCTION Egypt is unique among the nations of the world due to its main dependence upon a single water

source. Irrigation for agriculture consumes the bulk of the available water supplies [1]. So, a lot of

improvements have been achieved at off-farm and on-farm systems in order to reduce the water losses

in the irrigation network. Off-farm system (Owned by the Ministry of Water Resources and Irrigation)

consists of irrigation network, main, secondary, and branch canals including all control structures. On

the other hand, on-farm system (owned by the farmer) consists of existing small scale earth channels

called mesqa and marwa including several single lifting pumps distributed randomly along the branch

canals as shown in Fig. 1.


195

Fig. 1a: On-farm irrigation system, Fig 1b: Several single lifting pumps basins at Qena

Governorate in Egypt.

At on-farm system, the improvement was done by replacing the existing open small channels Mesqa

and Marwa (owned by the farmer) into another alternative, in addition to reducing the multiple single

lifting pumps along the branch canals into main pump station. Low pressure pipeline is the most

common used alternative between other alternatives (Improved lined mesqa, and raised concrete mesqa)

[2] as shown in Fig. 2.

Fig. 2a: Improved on-farm irrigation system

Fig 2b: Main pump station instead of multiple single

lifting pumps.

The Improved Irrigation Projects (IIP) was started at 1989 by replacing the existing earth cross section

of Mesqa by low pressure pipeline. IIP started in eleven canal commands with the aim to improve almost

400,000 feddan at on-farm level [3]. Next in 1996, Egypt started with the World Bank/KfW to tackle

improvement of about 250,000 feddan in the northern part of the Nile Delta in Beheira Governorate , and

Kafr el Sheikh Governorate [4]. The main objectives of IIP can be summarized in improving the

efficiency of water uses at on-farm level, improving the quality of irrigated water, increasing the

cultivated lands by about 3% (occupied area by earth channel) [5], increasing the crop yield from 5 to

30% due to better irrigation condition, and decreasing the irrigation time due to continuous flow [6-8].

The Egyptian Government is planning to continue the improvement works to reach a target of more than 3

million feddan by the year 2017 [3,9,10]. Due to the importance of irrigation efficiency, Integrated

Irrigation Improvement and Management Project (IIIMP) comes to overcome some problems of IIP. In

Egypt, this project is financed by the World Bank, German Development Bank KfW, the Kingdom of the

Netherlands and the Government of Egypt (GoE) [4]. The IIIMP is expected to increase irrigation

efficiency and more sustainable use of land and water by replacing marwa from its earth cross section to

low pressure pipeline as improved mesqa. The main objectives of IIIMP are to study the environmental

contamination by diesel pumps used in IIP and converting them to electrical pumps, and study

unsatisfactory operation of the irrigation system under continuous flow conditions due to no systematic

planning of water scheduling [11, 12]. This unsatisfactory operation between farmers causes unequal

water distribution between opened outlets to the extent that some farmers suffer from water shortage

during their opening. The required operational conditions to achieve fairness water distribution between

beneficiaries in case of laser leveling have been determined in previous study [13]. Allowable limits for


196

the concept of fairness water distribution are established with allowable difference in the discharge

between opened hydrants with four limits 5%,10%,15%, and 20%. The proposed distance between

opened hydrants was determined to achieve the various limits of the discharge differences. Finally,

standard graphs and tables are provided and can be used to control the operating cases between opened

hydrants in improved irrigation projects in Egypt. These graphs and tables are studied for the case of laser

leveling to achieve fairness water distribution between beneficiaries. The main objective of this paper is

how to achieve fairness water distribution between beneficiaries in the general case of varied ground

levels between opened hydrants.

2. DESIGN CONCEPT OF IMPROVED ON-FARM IRRIGATION SYSTEM The main components of Improved Irrigation Project in On- Farm System consists of three main

components as shown in Fig. 3. First component is improved mesqa or branch mesqa with low pressure

pipeline (IIP project), and the second is improved marwa with low pressure pipeline (IIIMP project). The

last component is pump station which takes its water from the branch canal through intake structure and

pump sump then injects its water directly to improved pipeline system of mesqa and marwa through

existing hydrants. The design of improved irrigation system is consisting of detecting the suitable

diameters for low pressure pipeline network for mesqa and marwa, and detecting the required pump

specifications to ensure extracting the designed water discharge from the far hydrant on the far marwa

pipeline. The design started by detecting the mesqa capacity from (1) considering the served area is

cultivated by Rice.

𝑄 =4200𝐴𝑊𝐷

𝑇, (1)

Where 𝑄,𝐴,𝑊𝐷 ,𝑎𝑛𝑑 𝑇 are mesqa capacity (l/sec.), total served area (feddan), water duty requirement

(mm/d), and working time per day (seconds); respectively. The calculated discharge is approximated to

multiples of 20 𝑙/𝑠 or 30 𝑙/𝑠 according to the designed hydrant discharge to detect the number of

opened hydrants at the same time. Then the suitable pipeline diameter (bearing head pressure of

4 𝑏𝑎𝑟𝑠) is selected from the available commercial diameters. The maximum design velocity is 1.5 𝑚/𝑠

according to the last design criteria to decrease the total project cost. The suitable pump is selected to

overcome the total head losses through the critical operating path. Head losses are divided into losses at

hydrants and losses through reaches. Total hydraulic head at hydrants is calculated from the following

Equation [14]:-

𝐻𝑇 = 𝐿𝐿 + 𝐻𝑅𝑖𝑠𝑒𝑟 + 𝑂𝑃 + 𝐶𝑄2 (2)

Where 𝐻𝑇 , 𝐿𝐿 ,𝐻𝑅𝑖𝑠𝑒𝑟 ,𝑂𝑃 ,𝑄 are total hydraulic head at hydrant (𝑚), land level at hydrant, height of the

riser above land level, required outlet pressure at hydrant (𝑚), and actual extracting discharge (𝑚3/𝑠𝑒𝑐.); respectively. Parameter 𝐶 is depending on the friction coefficients, and it can be calculated from

the following equation 𝐶 = 𝐾𝑇/(2𝑔 𝐴𝑅𝑖𝑠𝑒𝑟2 ). Where 𝐾𝑇 is the summation of total friction coefficients

at hydrant location (taken 4). Parameters 𝑔 ,𝑎𝑛𝑑 𝐴𝑅𝑖𝑠𝑒𝑟 are the gravity acceleration (9.8 𝑚/ sec2 ), and cross section area of the riser pipe (𝑚2); respectively. Head losses through reaches are divided into

minor and main losses, for more details about minor losses see [15]. Main friction losses through

improved mesqa or marwa pipelines (𝑕𝑓 ) are calculated using Hazen-William equation:-

𝑕𝑓 = 3.59 𝑄

𝐶𝐻

1.852

𝐿

𝐷4.87 (3)


197

Fig. 3: Main components of Improved Irrigation system at on-farm level.

Where 𝐻𝑓 ,𝐶𝐻,𝐷, 𝐿 are friction losses in pipeline (𝑚), coefficient taken 150 for 𝑃𝑉𝐶 pipe, diameter

of pipeline reach (𝑚) , and length of pipeline reach (𝑚); respectively. The previous design steps have

been programmed using Matlab software [16,17]. There was concern about the high cost of the IIP

improvements (civil works and associated equipment), which has increased from about 2,300 𝐿𝐸/𝑓𝑒𝑑

at the time of mid-term review in May 2000 to about 5,600 𝐿𝐸/𝑓𝑒𝑑 in 2004 [18]. To repay the costs

of improvements, farmers would have to make annual payments per feddan per year over several years

ranges from 10 to 20 year. So any reduction in the total improved system can relief something from

the farmer’s problem [1]. The new developed program has helped in discussing the available methods

to reduce the total improvement's costs [19,20].

3. THE REQUIRED CONDITIONS FOR EQUITABLE WATER DISTRIBUTION BETWEEN

OPENED HYDRANTS. This section deals with the conditions that should be achieved at operation scenarios to ensure

equity water distribution between opened hydrants. The total hydraulic head (𝐻𝑇) along pipeline

system between two hydrants (𝑖 ,𝑎𝑛𝑑 𝑗) is governed by the following equations (neglecting the

difference in the velocity head between the two hydrants), see Fig. (4).

𝐻𝑇𝑖 = 𝐿𝐿𝑖 + 𝐻𝑟𝑖𝑠𝑒𝑟 𝑖 + 𝑂𝑃𝑖 + 𝐶𝑄𝑖2 (4𝑎)

𝐻𝑇𝑗 = 𝐿𝐿𝑗 + 𝐻𝑟𝑖𝑠𝑒𝑟𝑗 + 𝑂𝑃𝑗 + 𝐶𝑄𝑗2 4𝑏

𝐻𝑇𝑗 = 𝐻𝑇𝑖 − 𝑕𝑙𝑖𝑗 (4𝑐)


198

Fig. 4: Illustrated figure for improved mesqa pipeline with earth marwa (IIP).

Where 𝑕𝑙𝑖𝑗 is the friction losses between hydrants (𝑖 ,𝑎𝑛𝑑 𝑗) .The previous equations can be rewritten to

get the following relationship between the discharge of any two hydrants.

)5()( 22 ahLLOOQQCijlLiLjPiPjji

Where:

)5(59.3

87.4

852.1

bD

L

CH

Qh

ij

ijjlij

)5(,,,)( ,22 cDLQLOfQQC ijijjLPji

Where Lij , and Dij are distance and diameter between opened hydrants. From (5a), there are several

scenarios that can represent the actual field situation. According to each actual scenario, the required

conditions that should be achieved to ensure fairness water distribution between opened hydrants can

be determined. The required operational conditions to achieve fairness water distribution between

beneficiaries in case of laser leveling, and constant outlet pressure (OP) have been determined [13].

This paper concerns with the case of constant outlet pressure (OP) for opened hydrants i & j (OPi =Opj)

and variable land levels. So Eq.(5a) can be rewritten as follows:

𝐶 𝑄𝑖2 − 𝑄𝑗

2 = 𝐿𝑖𝑗 𝑆 + 3.59𝑄𝑗

𝐶𝐻

1.852

𝐿𝑖𝑗

𝐷𝑖𝑗4.87 (6)

The friction term is always a positive value. But, the term of the difference between land levels

(𝐿𝑖𝑗 ∗ 𝑆 ) can be positive and negative according to the slope direction (S) (upward or downward) as

shown in Fig. 5. For upward slope, the right hand side of (6) is always positive, which means that the

nearest opened outlet 𝑄𝑖 is always extracts flow larger than the far opened outlet 𝑄𝑗 . For downward

slope, the relationship between the flow of opened hydrants depends on the net result sign of the right

hand side of (6).

(a)


199

(b)

Fig.5. Illustrated figure for (a) Upward slope, and b) Downward slope.

3.1 Upward Slope For upward slope, the expected discharge for the nearest opened hydrant will be always larger

than the discharge of the far one. Due to the larger number of unknowns in (6), the discharge for the

far hydrant will be assumed with two default values of designed discharge of 20 𝑙/𝑠𝑒𝑐., and 30 𝑙/𝑠𝑒𝑐. Then the expected discharge at the near opened hydrant will be calculated taking into consideration

the effect of other different variables such as distance between opened hydrants, upward slope,

diameter of the reach between the two opened hydrants. Table 1 illustrates the accepted distance along

mesqa pipeline between selected opened hydrants (Marwas) for different upward land slopes to

achieve certain differences in the discharges between opened hydrants ∆𝑄%. Four different limits for

∆𝑄% are assumed and the final decision is left to the decision maker. Table 1 can be used to select the

hydrants (Marwas) that should be opened at the same time depending on the maximum accepted

distance between opened hydrants illustrated in the table. The selection of opened hydrants (Marwas)

depends also on the actual land slope along mesqa pipeline, and the required difference in the

extracted discharge between opened hydrants.

Table 1: Maximum accepted distance between selected opened hydrants ( ijL ) in meter for various

percentages of the difference in the flows (∆𝑸%)- Upward slope.

S %

∆𝑸%

𝑫𝒊𝒋(𝒎𝒎)

𝑄𝑗 = 20 𝑙/𝑠𝑒𝑐 𝑄𝑗 = 30 𝑙/𝑠𝑒𝑐

200 225 250 280 225 250 280 315

0.0

5 11.72 20.76 34.66 60.18 9.06 15.07 26.19 46.46

10

25.39 45.04 75.24

130.6

7 19.60 32.75 56.84

100.8

6

15

41.59 73.77

123.2

1

213.9

5 32.12 53.60 93.07

165.1

4

20

60.88

108.0

3

180.4

4

313.3

4 47.01 78.49

136.2

9

241.8

5

0.05

5 9.53 14.76 20.67 27.67 7.63 11.45 16.86 23.41

10 20.68 32.07 44.86 60.03 16.49 24.80 36.56 50.81

15 33.86 52.50 73.46 98.31 26.97 40.62 59.84 83.19

20

49.55 76.87

107.5

8

143.9

7 39.45 59.47 87.65

121.8

3

0.1 5 8.08 11.49 14.72 17.97 6.58 9.22 12.44 15.65

10 17.47 24.87 31.98 38.98 14.20 19.96 26.96 33.97


200

15 28.56 40.74 52.34 63.82 23.25 32.72 44.11 55.60

20 41.81 59.65 76.64 93.46 34.01 47.90 64.58 81.43

0.15

5 7.00 9.38 11.46 13.32 5.77 7.752 9.83 11.78

10 15.06 20.33 24.82 28.87 12.52 16.75 21.35 25.51

15 24.67 33.31 40.64 47.26 20.40 27.40 34.91 41.77

20 36.14 48.75 59.51 69.19 29.85 40.06 51.15 61.15

0.2

5 6.16 7.97 9.36 10.56 5.12 6.67 8.18 9.42

10 13.32 17.23 20.29 22.94 11.15 14.39 17.69 20.42

15 21.77 28.17 33.24 37.53 18.24 23.56 28.92 33.45

20 31.85 41.22 48.66 54.91 26.66 34.46 42.35 48.97

0.25

5 5.48 6.91 7.95 8.78 < 5.0 5.84 7.00 7.90

10 11.92 14.88 17.20 19.02 10.01 12.66 15.05 17.07

15 19.42 24.38 28.12 31.11 16.46 20.65 24.66 27.91

20 28.46 35.70 41.15 45.54 24.05 30.21 36.12 40.83

0.3

5 < 5.0 6.09 6.90 7.53 < 5.0 5.18 6.09 6.78

10 10.74 13.18 14.86 16.25 9.18 11.27 13.18 14.61

15 17.60 21.53 24.35 26.59 14.94 18.42 21.53 23.93

20 25.70 31.50 35.64 38.91 21.94 26.95 31.51 34.99

0.35

5 < 5.0 5.43 6.08 6.58 < 5.0 < 5.0 5.38 5.93

10 9.78 11.80 13.17 14.18 8.47 10.11 11.70 12.84

15 16.04 19.25 21.50 23.22 13.78 16.62 19.09 20.95

20 23.47 28.19 31.46 33.96 20.08 24.27 27.95 30.65

0.4

5 < 5.0 < 5.0 5.42 5.82 < 5.0 < 5.0 < 5.0 5.24

10 9.04 10.65 11.79 12.62 7.85 9.25 10.47 11.42

15 14.71 17.45 19.23 20.57 12.78 15.07 17.17 18.65

20 21.59 25.47 28.16 30.10 18.63 22.13 25.05 27.29

3.2 Downward Slope

For downward slope (negative slope), the relationship between the extracted discharge of near

and far hydrants in the network depends on the summation of the two parts on the right hand side in

(6) as follows:-

)7(

)(..:3

)(..:2

)(0.0..:1

)7(59.3

*.. 87.4

852.1852.1

b

QQveSHRSSCase

QQveSHRSSCase

QQSHRSSCase

aD

LQ

CHSLSHR

jic

jic

jic

ij

ijjij

From the previous equations, there are three different operating cases that can be happened with

different characteristics in the system as shown in Fig.6. These cases will be discussed in details in the

following sections.


201

Fig.6: Illustrated figure for the three cases of downward slope.

Case (1): Calculation of the critical downward slope for equal discharges.

In this case, the critical downward slope that is needed to achieve exactly equal water

distribution between opened hydrants will be determined. The critical downward slope for exactly

equal water distribution (𝑄𝑖 = 𝑄𝑗 = 𝑄) can be determined from (7a) as follows:

)8(1

*59.3

87.4

852.1

ijc DCH

QS

Where 𝑆𝑐 ,𝑄,𝐷𝑖𝑗 are critical downward slope for equal water distribution between opened hydrants,

designed discharge for the near and far hydrant (𝑄𝑖 = 𝑄𝑗 ) in (𝑚3/sec), and reach's diameter between

opened hydrant (m); respectively. The critical slopes illustrated in Table (2) can be achieved by two

methods; first method by changing the land level and keep imbedded pipelines horizontally, and

second method by changing the slope of the imbedded pipelines and keep land level horizontally as

shown in the Fig.7. From the practical point of view, second method is preferred and applicable rather

than first one.

Table 2: Critical downward slope (m/m) for exactly equal water distribution between opened hydrants.

Designed hydrant

discharge (𝒍/𝒔𝒆𝒄)

Reach diameter ijD (mm)

200 225 250 280 315

20 0.2188 0.1233 0.0738 0.0425 0.0240

30 0.4630 0.2612 0.156 0.090 0.051

40 0.7900 0.4450 0.27 0.150 0.087

50 1.1940 0.6730 0.4 0.232 0.131

Fig.7: Achieving the critical slope by inclined imbedded pipelines.


202

Case (2): When cSS0.0

As the land slope decreases from the horizontal situation to the critical downward slope (Sc), as the

difference in the discharge between nearest opened hydrant and far opened hydrant disappeared

(∆𝑄 = 𝑄𝑖 − 𝑄𝑗 ) until reaching zero at the critical slope (Sc). By assuming constant discharge for the

nearest opened hydrant, the discharge for far opened outlet be determined from (6) as follows:

)9(059.3

* 87.4

852.1852.122

cij

ijjijij SS

D

LQ

CHSLQCQC

Due to non-linearity of (9) in calculating(𝑄𝑗 ),so Newton Raphson method is used for solving the

previous equation as follows [21]:

)10()(

)(

)10(852.12)(

:

)10(0.0)(

)10(0*,59.3

)(\

)(

)()1(

852.0

)()()(\

852.12

287.4

852.1

dQf

QfQQ

cQyQCQf

kiterationFor

bWQyQCQf

aSSwhereSLQCWD

L

CHyLet

kj

kj

kjkj

kjkjkj

jjj

cijiij

ij

In addition to the non-linearity of (10) in determining the flow for far opened hydrant, also it depends

on several variables. These variables are the designed hydrant discharge for nearest outlet (𝑄𝑖), slope

(𝑆), distance between opened hydrants (𝐿𝑖𝑗 ), and reach's diameter between opened hydrants (𝐷𝑖𝑗 ).

Figure 8 illustrates an example for the variation of the discharge for the far opened hydrant as a

function of 𝑆 and 𝐿𝑖𝑗 for different 𝑄𝑖 and 𝐷𝑖𝑗 . Table 3 illustrates the maximum distance between

opened hydrants to achieve accepted difference in the flow (∆𝑄).

Fig. 8: Relationship between the discharge of far opened hydrant and the distance between opened

hydrants for downward slopes cSS0.0


203

Table 3: Maximum distance between selected opened hydrants (𝑳𝒊𝒋) in meter for various percentages

of the difference in the flows- Downward slope cSS0.0

Slo

pe

%

∆𝑸%

𝑫𝒊𝒋 (𝒎𝒎)

𝑄𝑗 = 20 𝑙/𝑠𝑒𝑐. 𝑄𝑗 = 30 𝑙/𝑠𝑒𝑐

200 225 250 280 225 250 280 315

-0.05

5 15.51 37.18 134.87 696.77 9.17 15.51 27.68 9.17

10 34.61 87.48 419.63 >1000 19.75 33.54 60.00 19.75

15 58.72 159.30 >1000 >1000 32.18 54.68 98.22 32.18

20 89.97 270.12 >1000 >1000 46.84 79.79 143.94 46.84

-0.1

5 23.36 190.59 126.26 45.37 15.48 50.40 >1000 50.30

10 56.25 >1000 415.99 100.85 36.10 144.64 >1000 116.12

15 106.11 >1000 >1000 169.86 64.87 384.73 >1000 205.34

20 190.56 >1000 >1000 257.64 107.91 >1000 >1000 332.47

-0.15

5 47.18 161.16 35.06 23.46 24.32 >1000 43.50 23.69

10 149.93 >1000 80.25 50.07 63.88 >1000 107.66 51.23

15 551.11 >1000 140.36 80.41 139.72 >1000 211.02 83.51

20 >1000 >1000 223.75 115.19 344.46 >1000 403.74 121.72

-0.2

5 >1000 37.33 20.36 15.82 56.67 77.60 22.07 15.49

10 >1000 93.96 44.42 33.31 277.80 341.20 49.51 32.87

15 >1000 189.47 73.15 52.69 >1000 >1000 84.43 52.42

20 >1000 382.98 107.89 74.18 >1000 >1000 130.12 74.49

-0.25

5 230.55 21.11 14.35 11.95 >1000 28.40 14.77 11.52

10 >1000 48.33 30.71 24.95 >1000 72.26 32.17 24.20

15 >1000 84.56 49.46 39.17 >1000 148.40 52.79 38.20

20 >1000 134.93 71.09 54.70 >1000 311.63 77.58 53.68

-0.3

5 40.09 14.71 11.09 9.58 159.02 17.40 11.13 9.16

10 127.57 32.54 23.48 19.94 >1000 40.40 23.82 19.15

15 460.46 54.43 37.38 31.18 >1000 72.26 38.40 30.04

20 >1000 81.91 53.02 43.34 >1000 118.82 55.25 41.96

-0.35

5 22.00 11.31 9.03 8.02 34.91 12.55 8.92 7.63

10 55.89 24.51 19.00 16.63 119.52 28.08 18.91 15.84

15 114.67 40.12 30.01 25.90 606.87 47.76 30.16 24.76

20 240.36 58.80 42.27 35.88 >1000 73.42 42.93 34.43

-0.4

5 15.12 9.18 7.64 6.89 19.62 9.78 7.46 6.52

10 35.79 19.67 15.96 14.25 51.91 21.51 15.68 13.52

15 65.50 31.80 25.08 22.16 114.25 35.66 24.84 21.07

20 111.62 45.86 35.13 30.61 283.68 53.13 35.07 29.20

Case (3): When cSS

As land slope decreases than the critical slope, the discharge of far opened hydrant will be larger than

the same of the nearest opened hydrant as in the following equation.

)11(,59.3

87.4

852.122 SSwhereLS

D

L

CH

QQCQC ij

ij

ijjji

Figure 9 illustrates an example for the variation of the discharge for the nearest opened hydrant with

respect to other parameters such as land slope, distance and diameter of the reach between opened

hydrants. Table 4 illustrates the accepted distance between opened hydrants for different four values of

discharge differences (∆𝑄). As seen from Fig.9, the discharge of the nearest opened hydrant will be

dissipated at certain conditions which can be calculated from the following equation:


204

)12(159.3

87.4

852.1

2

ij

j

jij

DCH

QS

QCL

Fig. 9: Relationship between the discharge of far opened hydrant and the distance between opened hydrants for

downward slopes cSS0.0

Table 4: Maximum accepted distance between selected opened hydrants (𝑳𝒊𝒋) in meter for various

percentages of the difference in the flows - Downward slope cSS

Slo

pe

%

∆𝑸%

𝑫𝒊𝒋(𝒎𝒎)

𝑄𝑖 = 20 𝑙/𝑠𝑒𝑐 𝑄𝑖 = 30 𝑙/𝑠𝑒𝑐

200 225 250 280 225 250 280 315

-0.05

5 15.16 34.90 107.46 307.69 11.19 22.18 58.85 >1000

10 32.93 75.78 233.31 599.60 24.25 48.12 127.78 >1000

15 53.89 124.08 382.02 875.74 39.68 78.78 209.22 >1000

20 78.91 181.72 559.47 >1000 58.13 115.36 306.41 >1000

-0.1

5 21.55 109.84 88.10 40.14 14.63 41.81 213.84 43.18

10 46.77 238.50 171.68 78.22 31.77 90.77 416.71 84.15

15 76.56 390.52 250.75 114.24 52.00 148.63 608.61 122.91

20 112.12 571.92 325.30 148.21 76.13 217.67 789.55 159.45

-0.15

5 37.19 86.39 30.29 21.46 21.21 369.32 35.48 21.42

10 80.74 168.35 59.03 41.83 46.02 801.90 69.15 41.76

15 132.20 245.89 86.21 61.10 75.34 >1000 100.99 60.99

20 193.60 318.99 111.84 79.27 110.33 >1000 131.01 79.12


205

-0.2

5 136.15 30.09 18.28 14.65 38.50 48.77 19.34 14.25

10 295.61 58.63 35.64 28.55 83.59 95.04 37.69 27.76

15 484.04 85.63 52.04 41.70 136.86 138.80 55.06 40.56

20 708.88 111.08 67.52 54.10 200.43 180.07 71.43 52.61

-0.25

5 73.94 18.21 13.09 11.11 209.86 22.71 13.29 10.67

10 144.09 35.49 25.52 21.66 455.65 44.27 25.91 20.79

15 210.45 51.83 37.27 31.64 746.09 64.67 37.84 30.38

20 273.02 67.24 48.35 41.06 >1000 83.89 49.09 39.41

-0.3

5 28.41 13.05 10.20 8.95 54.87 14.81 10.13 8.52

10 55.38 25.45 19.88 17.45 106.92 28.85 19.74 16.61

15 80.88 37.16 29.03 25.50 156.16 42.14 28.82 24.28

20 104.94 48.21 37.65 33.07 202.59 54.68 37.39 31.49

-0.35

5 17.58 10.18 8.34 7.48 23.96 10.98 8.16 7.08

10 34.27 19.84 16.27 14.62 46.69 21.40 15.93 13.83

15 50.06 28.96 23.77 21.34 68.19 31.25 23.27 20.23

20 64.95 37.57 30.84 27.68 88.47 40.56 30.21 26.22

-0.4

5 12.72 8.32 7.05 6.43 15.33 8.72 6.84 6.07

10 24.82 16.24 13.77 12.55 29.87 16.99 13.35 11.84

15 36.24 23.72 20.14 18.35 43.62 24.85 19.52 17.30

20 47.01 30.78 26.10 23.81 56.59 32.21 25.33 22.45

4. CONCLUSIONS

This paper discussed the required operational conditions for opened hydrants on the improved on-

farm irrigation projects in Egypt to achieve fairness water distribution between beneficiaries. An

accepted and allowable limits for the concept of fairness water distribution have been established.Four

allowable limits for the difference in the discharge between opened hydrants with 5%, 10%, 15%, and

20% have been introduced. The required conditions for achieving each limit of the above limits were

developed, and the final decision for the used limit is left to the decision makers.This paper discussed

the variation of land levels along improved mesqa pipeline either for downword and upword slopes

through:-

Determining the maximum distance between opened hydrants for achieving various accepted

difference in the discharge for upward slope.

Determining the critical downward slope for exactlly equal water distribution between opend

hydrants regardless of the distance between opened hydrants. It is suggested that these slopes can

be achieved during the implementation of the imbeded pipeline network and not on the land level

(if available).

Determinig the accepted distance between opened hydrants for other downward slopes around

the critical downward slope for achieving certain difference in the discharge between opened

hydrants.

So, finally this paper presented guideline tables for the operational scenarios between hydrants at on-

farm irrigation development projects in Egypt in order to achieve fairness water distribution.


206

REFRENCES

Alnagar, D., 2005. Policies and strategic options for water management in the Islamic countries, IHP-

VI Technical Documents in Hydrology, UNESCO Working Series SC-2005/WS/2.

Allam, M. ,2005. Integrated Irrigation Improvement and Management Project (IIIMP). Final EA Study

Report.

Allam, M., El-Gamal, F., Hesham, M. ,2005. Irrigation Systems Performance in Egypt. Options

méditerranéennes conference, Series B, n°52.

Allam, M.,2004. Participatory Irrigation Water Management in Egypt: Review and Analysis. Options

méditerranéennes conference, Series B, n° 48.

Depeweg, H., Bekhite, K.H., 1997. Evaluation of proposed mesqa improvements. Journal of

Irrigation and Drainage Systems, 11, 299–323.

Deuflhard, P. , 2011. Newton Methods for Nonlinear Problems. first Edition. Springer Series in

Computational Mathematics, Volume 35 .

Elshorbagy, W., E. ,2000.Impact Assessment of an Irrigation Improvement Project in Egypt. Journal

Water Resources Management, Vol. 14, pages 229-246.

Hvidt, M., 1995. Current efforts to improve irrigation performance In Egypt. The third Nordic

conference on Middle Eastern Studies: Ethnic encounter and culture Change Joensuu, Finland.

Mott Macdonald, Sabour associates ,2004. Note on proposals for reduction of costs of masqa

Improvement. Ministry of water resources and irrigation.

Nucleo di Ricerca sulla Desertificazione (NRD),2005. Plan of Action for an Integrated Coastal Zone

Management in the Area of Port Said (Egypt) Pilot Action Proposal. The European union’s Short

and Medium-term Priority environmental Action Programme (SMAP).

NEPAD, 2005. Support to NEPAD–CAADP Implementation . Bankable Investment Project Profile.

Oosterbaan, R.J., 2010. Impacts of the Irrigation Improvement Projects In Egypt. Consultancy Report

to the Egyptian-Dutch Advisory Panel on Land Drainage and Drainage Related Water

Management.

On- Farm Irrigation Development Project in Old-Lands (OFIDO),2007.Terms of Reference for the

Tendering of Consulting Services for the Integrated Irrigation Improvement and Management

Project (IIIMP) and Instruction to Tenders.

Radwan, H., G., (2015), Fairness Water Distribution at On-Farm Irrigation Development Projects In

Egypt - Case of Laser Levelling, International Journal of Research in Chemical, Metallurgical and

Civil Eng. (IJRCMCE) Vol. 2, Issue 2, pages 100-104.

Radwan, H., G., Zaghloul, A., Ibrahim, K. ,2010(a). Modified Technique for Design The Improved

Irrigation on-Farm System. International Conference on Modeling, Simulation and Control

(ICMSC 2010), pages (174-179).

Radwan, H., G., Zaghloul, A. , Ibrahim, K. ,2011(a). Analysis of Optimal Velocity for Improved

Irrigation Design in Egypt. Canadian Journal on Environmental, Construction and Civil

Engineering Vol. 2, No. 5, pages (94-102).

http://ressources.ciheam.org/om/pdf/b48/05002288.pdf

http://www.amazon.com/s/ref=ntt_athr_dp_sr_1?_encoding=UTF8&field-author=Peter%20Deuflhard&ie=UTF8&search-alias=books&sort=relevancerank

http://link.springer.com/bookseries/797



http://www.waterlog.info/pdf/irrimpr.pdf


207

Radwan, H., G. ,2011. Design Program for Integrated Improved Farm Irrigation System in Old Lands

of Delta Egypt. Phd thesis, Irrigation and Hydraulics Dept., Faculty of Engineering , Cairo

University, Egypt.

Radwan, H., G., Zaghloul, A., Ibrahim, K. ,2010(b). Modified Technique of Irrigation Model:Design

and Sensitivity Analysis. International Conference on Modeling, Simulation and Control (ICMSC

2010), pages (82-86).

Radwan, H., G., Zaghloul, A. , Ibrahim, K.,2011(b). Practical Design of Improved Irrigation

Projects in Egypt under Specific Constraints. Canadian Journal on Environmental, Construction

and Civil Engineering Vol. 2, No. 5, pages (103-110).

Radwan, H., G.,2013. Sensitivity Analysis of Head Loss Equations on the Design of Improved

Irrigation On-Farm System in Egypt. In International Journal of Advancements in Research &

Technology, Volume 2, Issue1

United Nations, 2003. Sectoral Water Allocation Policies in Selected ESCWA Member Countries: An

evaluation of the economic, social and drought-related impact, New York.