Hydraulic Engineering Design Manual

Hydraulic Engineering Design Manual
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Hydraulic Engineering
Design Manual
Prepared by:
Salik Haroon Abbasi
(MSc in Hydraulic and Irrigation Engineering)

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1 Table of Contents
1 To Develop the Relationship Between the Surface Area,
Elevation and Capacity of Reservoir. ..................................................1
1.1 Objectives:....................................................................................................................1
1.2 Related Theory:.............................................................................................................2
1.2.1 Reservoir: ..............................................................................................................2
1.2.2 Practical importance of surface area, elevation and capacity curve: ........................8
1.2.3 Methods for determination of storage capacity: ......................................................9
1.3 Procedure:...................................................................................................................10
1.4 Calculations ................................................................................................................10
1.5 Graphs ........................................................................................................................11
1.5.1 Graph between Elevation between Cum. Mean Vol..............................................11
1.5.2 Graph between Elevation between Mean Surface Area.........................................12
1.6 Comments:..................................................................................................................13
2 To estimate the live storage capacity of reservoir for various
operational scenarios ..........................................................................14
2.1 Objective: ...................................................................................................................14
2.2 Related Theory:...........................................................................................................14
2.2.1 Reservoir: ............................................................................................................14
2.2.2 Capacity of reservoir:...........................................................................................15
2.2.3 Levels:.................................................................................................................15
2.2.4 Storage Capacity:.................................................................................................16
2.2.5 Yield:...................................................................................................................16
2.2.6 Uniform Draw off (UDO) ....................................................................................17
2.2.7 Surplus and Deficit: .............................................................................................17
2.2.8 Mass Curve:.........................................................................................................17
2.3 Procedure:...................................................................................................................18
2.4 Calculations ................................................................................................................19

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2.5 Graphs ........................................................................................................................21
2.5.1 Mass Curves ........................................................................................................21
2.5.2 Inflow and Outflow Hydrographs.........................................................................22
2.6 Results:.......................................................................................................................24
2.7 Comments:..................................................................................................................24
3 To estimate hydropower potential for a given waterpower
development scheme. ..........................................................................25
3.1 Objective: ...................................................................................................................25
3.2 Related Theory:...........................................................................................................25
3.2.1 Source of Energy: ................................................................................................25
3.2.2 Water Power Plant: ..............................................................................................25
3.2.3 Pump Storage Plant:.............................................................................................26
3.2.4 Sizes of hydropower Plant:...................................................................................26
3.2.5 Firm Power:.........................................................................................................27
3.2.6 Flow Duration Curve: ..........................................................................................27
3.2.7 Power Duration Curve: ........................................................................................27
3.3 Procedure:...................................................................................................................28
3.4 Problem Statement:.....................................................................................................29
3.5 Calculation Table:.......................................................................................................29
3.6 Graphs: .......................................................................................................................31
3.6.1 Power Duration Curve .........................................................................................31
3.6.2 Flow Duration Curves..........................................................................................32
3.6.3 Combined Graphs of all cases: .............................................................................34
3.7 Results:.......................................................................................................................35
3.8 Comments:..................................................................................................................35
4 Estimation of Bed Load, Total Sediment load and Bed of
Reservoir..............................................................................................36
4.1 Objective: ...................................................................................................................36
4.2 Related Theory:...........................................................................................................36
4.2.1 Sediment Terminology.........................................................................................36
1. Sediment:....................................................................................................................36

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2. Sediment Discharge: ...................................................................................................36
3. Sediment Transport:....................................................................................................36
4. Sediment Yield: ..........................................................................................................37
5. Bed Load: ...................................................................................................................37
6. Bed Load Transport: ...................................................................................................37
7. Suspended Load:.........................................................................................................37
8. Bed Material Load: .....................................................................................................37
9. Wash Load/Fine Load:................................................................................................37
4.2.2 Total load transport:.............................................................................................37
4.2.3 Capacity Terminology..........................................................................................38
1. Capacity Inflow Ratio: ................................................................................................38
2. Life of a Reservoir: .....................................................................................................38
3. Half-life of Reservoir: .................................................................................................38
4. Trap Efficiency: ..........................................................................................................38
4.2.4 Approaches used to estimate Bed load and Total sediment load: ..........................38
4.3 Problem Statement:.....................................................................................................39
4.4 Procedure:...................................................................................................................39
4.6 Results ........................................................................................................................41
4.7 Comments:..................................................................................................................42
5 Computation of GVF profile by standard step method. .............43
5.1 Objective: ...................................................................................................................43
5.2 Related Theory:...........................................................................................................43
5.2.1 Gradually Varied Flow:........................................................................................43
5.2.2 Assumptions for gradually varied flow:................................................................43
5.2.3 Gradually Varied Flow Profiles:...........................................................................44
7. Free over fall (mild slope ............................................................................................48
5.2.4 Limitations of gradually varied flow equation: .....................................................48
5.2.5 Methods to Compute Gradually Varied Flow Profiles: .........................................49
5.3 Procedure....................................................................................................................50

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5.5 GVF Profile: ...............................................................................................................52
5.6 Comments:..................................................................................................................52

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Design No:1
1 To Develop the Relationship Between the Surface Area,
Elevation and Capacity of Reservoir.
1.1 Objectives:
o To develop the elevation and surface area curve.
o To develop the elevation and capacity curve.
o To develop the relationship between surface area and capacity.
o To correlate the elevation, surface area and capacity of reservoir to check the feasibility of
the project.

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1.2 Related Theory:
1.2.1 Reservoir:
An area occupied by the weir body due to the construction of dam is called as reservoir, it is an
artificial lake, storage pond, or impoundment from a dam which is used to store water.
Reservoirs may be created in river valleys by the construction of a dam or may be built by
excavation in the ground or by conventional construction techniques such as brick work or cast
concrete.
There are two types of storage reservoirs:
o On-stream reservoirs are fed by a water catchment.
o Off-stream reservoirs receive water transferred from on –stream reservoirs or other sources

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1. Flood control reservoir:
It is constructed for the purpose of flood control and it protects the area on the downstream side
from the damage due to flood.

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2. Detention reservoir:
It stores excess water during flood and releases it after the flood. It is similar to storage reservoir
but is provided with large gated spillways and sluice ways to permit the feasibility operations.
Detention reservoirs systems are provided for reducing the peak flows downstream of a
reservoir. The flow reduction is due to the storage volume of the reservoir in which the incoming
flow is temporarily stored.
3. Distribution reservoir:
It is a small storage reservoir to tide over the peak demand of water for water supply and
irrigation, it stores water during the lean period and supply is the same during the period of high
demand.

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Following are the main features of distribution reservoirs:
o Provide service storage to meet widely fluctuating demands imposed on system.
o Accommodate fire-fighting and emergency requirements.
o Equalize operating pressures.
o
Types of Distribution Reservoirs:
a. Surface Reservoirs:
At ground level - large volumes.
b. Standpipes
Cylindrical tank whose storage volume includes an upper portion (useful storage) usually less
than 50 feet high.
c. Elevated Tanks
Elevated Tanks used where there is not sufficient head from a surface reservoir - must be
pumped to, but used to allow gravity distribution in main system.

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4. Multipurpose Reservoir
The term multipurpose reservoir includes all reservoirs actually designed and operated to serve
more than one function and that it excludes those whose design and operation are controlled by a
single function, even though other benefits accrue as by-products. There can be several purposes
for which a reservoir may be made. If some of these purposes are combined there will be more
effective utilization of water and economical construction of a reservoir. Preferable combinations
for a multipurpose reservoir are:
Reservoir for Irrigation and Power
Reservoir for Irrigation, Power and Navigation.
Reservoir for Irrigation, Power and Water supply.
Reservoir for Recreation, Fisheries and Wild life.
Reservoir for Flood control and water supply.
Reservoir for Power and Water supply.

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5. Balancing Reservoir:
It is a small reservoir constructed downstream of the main reservoir for holding the water,
released from main reservoir.
6. Retarding Reservoirs
A retarding reservoir is provided with spillways and sluiceways which are ungated. The retarding
reservoir stores a portion of the flood when the flood is rising and releases it later when the flood
is receding.

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1.2.2 Practical importance of surface area, elevation and capacity curve:
1. E-S Curve:
It is used in site selection before the construction and this curve provides the information about
the land that is required for the reservoir, people evacuation, forest cutting and other
environmental purposes.
This curve needs a modification time to time as the available area corresponding to elevation
changes frequently due to sedimentation or erosion which will affect the reservoir capacity.
2. E-C Curve:
They are important to calculate the storage capacity by relating the height and to estimate the
following elevation levels:
Maximum elevation level
Operational elevation level
Dead elevation level
The storage capacity of the reservoir at any elevation is determined from the water spread area at
various elevations. An elevation – storage volume is plotted between the storage volume as
abscissa and the elevation as ordinate. Generally, the volume is a calculated in Mm3
or M ham.
The following formulae are commonly used to determine the storage capacity.

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3. S – C Curve:
This curve provides the information about the area that is under the water.
4. E – S – C Curve:
This curve is used to check the feasibility of the project.
1.2.3 Methods for determination of storage capacity:
The following formulae are commonly used to determine the storage capacity.
1. Trapezoidal formula:
According to the trapezoidal formula, the storage volume between two successive contours of
areas A1 and A2 is given by:
∆V = h/2 (A1+A2)
Where h is the contour interval. Therefore, the storage volume V is
V= h/2 (A1+2A2+2A3+2A4+……………. +2An-1+An)
Where n is the total number of areas.
2. Cone formula:
According to the cone formula, the storage volume between two successive contours of areas A1
and A2 is given by:
∆V=h/3 (A1+A2+√A1A2

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1.3 Procedure:
o L-section and cross-section of reservoir is given for different Heights H1, H2, H3 and H4.
o Divide the elevation of reservoir into different intervals.
o Calculate Top width of L-section using formula
o Top Width =
Interval
Slope
× Bottom Width
o Calculate Top width of cross-section using formula
o Top Width = 2×
Interval
Slope
× Bottom Width
o Calculate Mean Surface Area by multiplying average width of L-section and cross-section.
o Calculate mean volume and Capacity.
S₁ (1:100) L₁ = R/15 = 13.5 Km H₁ = S₁*L₁ = 0.135 Km
S₂ (1:150) L₂ = R/15 = 13.5 Km H₂ = 0.09 Km
S₃ (1:200) L₃ = R/10 = 20.2 Km H₃ = 0.101 Km
S₄ (1:300) L₄ = R/10= 20.2 Km H₄ = .067 Km
1.4 Calculations
Interval
(m)
z₁ z₂ z₂-z₁ Bottom width Top width Avg. Bottom width Top width Avg.
1 0 19.65 19.65 0 1965 982.5 80 178.25 129.125 126865.3125 2.49 0.00
2 19.65 39.3 19.65 1965 3930 2947.5 178.25 276.5 227.375 670187.8125 13.17 0.02
3 39.3 58.95 19.65 3930 5895 4912.5 276.5 374.75 325.625 1599632.813 31.43 0.05
4 58.95 78.6 19.65 5895 7860 6877.5 374.75 473 423.875 2915200.313 57.28 0.10
5 78.6 98.25 19.65 7860 9825 8842.5 473 571.25 522.125 4616890.313 90.72 0.20
6 98.25 117.9 19.65 9825 11790 10807.5 571.25 669.5 620.375 6704702.813 131.75 0.33
7 117.9 137.55 19.65 11790 14737.5 13263.75 669.5 767.75 718.625 9531662.344 187.30 0.51
8 137.55 157.2 19.65 14737.5 17685 16211.25 767.75 924.95 846.35 13720391.44 269.61 0.78
9 157.2 176.85 19.65 17685 20632.5 19158.75 924.95 1082.15 1003.55 19226763.56 377.81 1.16
10 176.85 196.5 19.65 20632.5 23580 22106.25 1082.15 1239.35 1160.75 25659829.69 504.22 1.67
11 196.5 216.15 19.65 23580 26527.5 25053.75 1239.35 1396.55 1317.95 33019589.81 648.83 2.31
12 216.15 235.8 19.65 26527.5 29475 28001.25 1396.55 1789.55 1593.05 44607391.31 876.54 3.19
13 235.8 255.45 19.65 29475 33405 31440 1789.55 1986.05 1887.8 59352432 1166.28 4.36
14 255.45 275.1 19.65 33405 37335 35370 1986.05 2182.55 2084.3 73721691 1448.63 5.81
15 275.1 294.75 19.65 37335 41265 39300 2182.55 2379.05 2280.8 89635440 1761.34 7.57
16 294.75 314.4 19.65 41265 45195 43230 2379.05 2575.55 2477.3 107093679 2104.39 9.67
17 314.4 334.05 19.65 45195 49125 47160 2575.55 2772.05 2673.8 126096408 2477.79 12.15
18 334.05 353.7 19.65 49125 55020 52072.5 2772.05 2968.55 2870.3 149463696.8 2936.96 15.09
19 353.7 373.35 19.65 55020 60915 57967.5 2968.55 3165.05 3066.8 177774729 3493.27 18.58
20 373.35 393 19.65 60915 66810 63862.5 3165.05 3361.55 3263.3 208402496.3 4095.11 22.67
Sr. No#
MSA
(m²)
Mean Vol.
(MCM)
Cum. Mean
Vol.
(BCM)
Elevation
(cm)
L-Section
(m)
X-Section
(m)

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1.5 Graphs
1.5.1 Graph between Elevation between Cum. Mean Vol
0
50
100
150
200
250
300
350
400
450
500
0.00 5.00 10.00 15.00 20.00 25.00
Elevation,E(m)
Cum. Mean Vol. (BCM)
Relation between Elevation & Cum. Mean Vol.

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1.5.2 Graph between Elevation between Mean Surface Area
0
50
100
150
200
250
300
350
400
450
500
120000 50120000 100120000 150120000 200120000
Elevation,E(m)
Mean Surface Area, MSA (m²)
Relation between Elevation & Mean Surface
Area
0.00 5.00 10.00 15.00 20.00 25.00 30.00
MEanSurfaceArea,E(m²)
Cum. Mean Vol. (BCM)
Relation between Mean Surface Area &
Capacity

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1.6 Comments:
E-S curve is very good in determining the area to be excavated for construction of reservoir
while E-C gave a very good idea about the fulfilling requirement of reservoir.
0.005.0010.0015.0020.0025.00
0
50
100
150
200
250
300
350
400
450
500
1.2E+05 1.0E+08 2.0E+08 3.0E+08
Capacity,C(BCM)
Elevation,E(m)
Mean Surface Area, MSA (m²)
Relation between Elevation & Mean Surface Area & Capacity
Elevation VS MSA
Elevation VS Capacity

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Design No:2
2 To estimate the live storage capacity of reservoir for various
operational scenarios
2.1 Objective:
o To calculate the live storage capacity for the following various capacities:
o When a constant maximum supply is insured from reservoir considering the losses due to
evaporation only (Q constant case)
o When specified discharges are to be released from the reservoir (Q varied case).
o Plot the mass curve for the two operational scenarios.
o To propose suitable emptying and filling time for the reservoir
2.2 Related Theory:
2.2.1 Reservoir:
It is a natural or artificial lake, storage pond, or impoundment developed from construction of dam,
which is used to store water.

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2.2.2 Capacity of reservoir:
It is defined as the maximum amount of water that can be stored in a reservoir. Factors affecting
capacity are availability and demand. The available storage capacity of a reservoir also depends
upon the topography of the site and the height of dam.
2.2.3 Levels:
1. Full Reservoir Level (FRL)/ Operational level:
It is the maximum capacity of water in the reservoir, which assures the supply of discharge from
the reservoir in full operational manner.
2. Maximum Water Level (MWL):
Maximum head available at the reservoir is termed as maximum water level.
3. Minimum Pool Level (MPL):
It is the minimum level of water in the reservoir, which is required for the stability of structure of
dam.

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2.2.4 Storage Capacity:
1. Dead Storage:
The volume of water held below the minimum pool level is called dead storage. Normally it is
equivalent to volume of sediment, expected to be deposited in the reservoir during the design life.
2. Live/Useful Storage:
The volume of water that is stored between full reservoir level and the minimum pool level is
called live/useful storage. It assures the supply of water for a specific period to meet the demand.
3. Flood/ Surcharge:
It is the storage held between mean water level and the full reservoir level. It varies with spillways
capacity of a dam for a given design flood.
2.2.5 Yield:
Amount of water released from reservoir is termed as yield.
1. Safe Yield:
It is the maximum quantity of water, which can be supplied uninterruptedly from a reservoir in a
specific period, during critical dry year.
2. Secondary yield:
It is the quantity of water, which is unavailable during the high flows when yield is more. It is
always higher than safe yield.
3. Average Yield:
It is the arithmetic mean of safe yield and secondary yield.
4. Design Yield:
It is the yield adopted for the design of reservoir; it depends upon urgency of water needs, the risk
involved in sedimentation requirement, design period, and the risk involved.

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2.2.6 Uniform Draw off (UDO)
It is the amount of water that is required to be withdrawn from a reservoir, uniformly during the
prescribed time. In Pakistan, it is done on the 10-daily basis by IRSA (Indus River System
Authority). It depends upon the downstream requirement of water.
2.2.7 Surplus and Deficit:
When inflow is more than outflow then the extra amount of water available in the reservoir is
termed as surplus whereas when the inflow is less than demand the amount of volume by which
water is deficient is called Deficit.
2.2.8 Mass Curve:
It is simply the combination of mass inflow curve or demand curve. I t is the plot between
cumulative inflows and the demands. This curve gives the information about the available water
at any time in the reservoir and it tells about the surplus and deficit to decide about the emptying

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2.3 Procedure:
Case no.1:
o Monthly inflow of one year is given.
o Consider losses as Roll No divided by 20.
o Calculate net inflow considering losses.
o Inflow volume should be in MCM .
o Calculate cumulative inflow volume.
o Monthly UDO is constant in this case and calculated as under
𝛴 𝑖𝑛𝑓𝑙𝑜𝑤 𝑜𝑓 𝑣𝑜𝑙𝑢𝑚𝑒
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o Same as step no. 5 calculate cumulative UDO.
o Subtract monthly UDO from Inflow volume. If the value comes out to be positive then put it
in surplus if negative then under deficit.
Case no.2:
o Inflow volume should be in MCM e.g. for 40 inflows, the inflow volume is 85.7 MCM.
R (𝑚3
/sec)
Where, R= roll number
Case no.3:
o Inflow volume should be in MCM
R× 5 + diff. values (𝑚3
/sec)
Where, R = roll number

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2.4 Calculations
Case#1
weeks
Inflows Net Inflows
Net Inflow
Vol.
Cum Inflow
Volume
Outflow
Volume
Cum UDO Surplus Deficit
(m³/sec) (m³/sec) (MCM) (MCM) (MCM) (MCM) (MCM) (MCM)
4 110 98.89 239.23 239.23 617.33 617.33 378.09
8 140 125.86 304.48 543.72 617.33 1234.65 312.85
12 190 170.81 413.22 956.94 617.33 1851.98 204.10
16 240 215.76 521.97 1478.91 617.33 2469.30 95.36
20 290 260.71 630.71 2109.61 617.33 3086.63 13.38
24 390 350.61 848.20 2957.81 617.33 3703.96 230.87
28 450 404.55 978.69 3936.50 617.33 4321.28 361.36
32 510 458.49 1109.18 5045.68 617.33 4938.61 491.85
36 440 395.56 956.94 6002.62 617.33 5555.93 339.61
40 380 341.62 826.45 6829.06 617.33 6173.26 209.12
44 280 251.72 608.96 7438.02 617.33 6790.58 8.36
48 150 134.85 326.23 7764.25 617.33 7407.91 291.10
52 120 107.88 260.98 8025.24 617.33 8025.24 356.34
1646.2 1646.2

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Case#2
weeks
Inflows Net Inflows
Net Inflow
Vol.
Cum Inflow
Volume
Outflow
Volume
Cum UDO Surplus Deficit
(m³/sec) (m³/sec) (MCM) (MCM) (MCM) (MCM) (MCM) (MCM)
4 110 98.89 239.23 239.23 488.6784 488.68 249.44
8 140 125.86 304.48 543.72 488.6784 977.36 184.20
12 190 170.81 413.22 956.94 488.6784 1466.04 75.45
16 240 215.76 521.97 1478.91 488.6784 1954.71 33.29
20 290 260.71 630.71 2109.61 488.6784 2443.39 142.03
24 390 350.61 848.20 2957.81 488.6784 2932.07 359.52
28 450 404.55 978.69 3936.50 488.6784 3420.75 490.01
32 510 458.49 1109.18 5045.68 488.6784 3909.43 620.50
36 440 395.56 956.94 6002.62 488.6784 4398.11 468.26
40 380 341.62 826.45 6829.06 488.6784 4886.78 337.77
44 280 251.72 608.96 7438.02 488.6784 5375.46 120.28
48 150 134.85 326.23 7764.25 488.6784 5864.14 162.45
52 120 107.88 260.98 8025.24 488.6784 6352.82 227.70
2538.37 899.24
Case# 3
week
Inflows Net Inflows
Net
Inflow
Vol.
Cum
Inflow
Volume
Outflow
Outflow
Volume
Cum
UDO
Surplus Deficit
(m³/sec) (m³/sec) (MCM) (MCM) (m³/sec) (MCM) (MCM) (MCM) (MCM)
4 110 98.89 239.23 239.23 207.00 500.77 500.77 261.54
8 140 125.86 304.48 543.72 217.00 524.97 1025.74 220.49
12 190 170.81 413.22 956.94 232.00 561.25 1587.00 148.03
16 240 215.76 521.97 1478.91 252.00 609.64 2196.63 87.67
20 290 260.71 630.71 2109.61 277.00 670.12 2866.75 39.41
24 390 350.61 848.20 2957.81 307.00 742.69 3609.45 105.50
28 450 404.55 978.69 3936.50 342.00 827.37 4436.81 151.32
32 510 458.49 1109.18 5045.68 382.00 924.13 5360.95 185.04
36 440 395.56 956.94 6002.62 417.00 1008.81 6369.75 51.87
40 380 341.62 826.45 6829.06 447.00 1081.38 7451.14 254.94
44 280 251.72 608.96 7438.02 472.00 1141.86 8593.00 532.90
48 150 134.85 326.23 7764.25 492.00 1190.25 9783.24 864.02
52 120 107.88 260.98 8025.24 507.00 1226.53 11009.78 965.55
441.867 3426.41

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2.5 Graphs
2.5.1 Mass Curves

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2.5.2 Inflow and Outflow Hydrographs

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2.6 Results:
o Live storage capacity for case no.1 is 8.53 MCM.
2.7 Comments:
Deficient reservoirs are not preferable to go with, the case “3” seems to be better than case “2”,
Case “3” is more efficient so preferable to go with that.

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Design No: 3
3 To estimate hydropower potential for a given waterpower
development scheme.
3.1 Objective:
o Plot the flow duration curve & power generation pattern curve.
o Calculate the primary and secondary hydropower without storage facilities.
o Calculate the total power generated annually, estimate the annual revenue generated by this
power plant if the cost per unit (KWH) is 2 PKR.
o Calculate Storage Capacity of reservoir when firm power of case “a” is to be doubled.
3.2 Related Theory:
3.2.1 Source of Energy:
o Fossil Fuel
o Wind Energy
o Water in river
o Solar Energy
o Waves and tides in ocean
o Atomic Energy
3.2.2 Water Power Plant:
Hydro power is extracted from the natural potential of useable water resources if water is available
in the river for the production of energy, resources are made so as to make the availability of the
water throughout the year and the power generated from the water can be computed through the
following formulas: P = ηγQH
Hydroelectric power plants are the systems which generate electricity following the law of
conservation of energy and the gravitational law. They are composed basically of a water reservoir,
turbines, electric motor or generator, rotors and stators and channeling pipes. The mechanism of

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hydroelectric power plants follows the transference of kinetic energy of flowing water to
mechanical energy of the blades when the water strikes with them forcefully.
3.2.3 Pump Storage Plant:
Another type of hydropower called pump storage works like a battery, storing the electricity
generated by other power sources like solar, wind and nuclear for later use. It stores energy by
pumping water uphill to a reservoir at higher elevation from a second reservoir at a lower elevation.
When the demand for electricity is low, pumped storage facility stores energy by pumping water
from a lower reservoir to an upper reservoir. During periods of high electrical demand, the water
is received back to the lower reservoir and turns a turbine generating electricity.
3.2.4 Sizes of hydropower Plant:
Facilities range in size from large power plants that supply many consumers with electricity to
small and micro plants that individuals operate for their own energy needs or to sell power to
utilities.
1. Large Hydropower:
Although definitions vary, DOE defines large hydropower as facilities that have a capacity of more
than 30 megawatts (MW).
2. Small Hydropower:
Although definitions vary, DOE defines small hydropower as projects that generate 10 MW or
less of power.
3. Micro Hydropower
A micro hydropower plant has a capacity of up to 100 kilowatts. A small or micro-hydroelectric
power system can produce enough electricity for a home, farm, ranch, or village.

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3.2.5 Firm Power:
It is the minimum power which can be generated from the hydro power plant for 100% of time. It
is the power corresponding to the minimum stream flow. It is the guaranteed power provided by a
power plant or transmission system.
3.2.6 Flow Duration Curve:
It is a plot of the stream flow in ascending or descending order and its frequency of occurrence as
percentage of time covered by the record.
3.2.7 Power Duration Curve:
If the available head and efficiency of the power plant are known, the flow duration curve may be
converted into power duration curve. Stream Flow Data Essential for the Assessment of Water

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3.3 Procedure:
Considering the given discharge data, calculations can be done in tabular form
o Col 1,2, 3, 4 from graph
o Net inflows = col 3 – (col 3 * col 4)
o Monthly Inflow yield (MCM) = Inflows(m3
/sec) * time / 106
o (Time = no of days in a respective month * 86400 sec)
o UDO outflow yield = summation of inflow yield/no of data records
o Surplus = col 6 – col 7 if result is a positive value
o Deficit = col 6 – col 7 if result is a negative value
o Cumulative inflows (MCM) = cumulative addition of column 6
o Cumulative UDO = the cumulative values of UDO.
o Capacity = The minimum of Cumulative surplus or Cumulative deficit
o For all these parts, plot the graphs
Time Time Inflows losses
Net
inflows
Net
monthly
inflow
yield
UDO
outflow
yield Surplus Deficit
(dates) (days) (m3
/sec) (%) (m3
/sec) (MCM) (MCM) (MCM) (MCM)
1 2 3 4 5 6 7 8 9

29
3.4 Problem Statement:
o For the following data relating to hydropower site:
o Calculate primary and secondary hydropower’s without storage facilities.
o Calculate storage capacity of reservoir if the outflows are defined for the case of UDO and
given outflows.
o Flow duration and power duration curves, annual revenue generated, proposed no. of turbines
to be installed and total power generated. Calculate annual power in KWh.
3.5 Calculation Table:
Case 1:
Total Power=4338468890 KWh
Cost of 1 unit is 4 rupee so the total revenue generated is=8676.94million rupees
For one turbine Discharge is= 50 m3
/s
So total no. of turbines = 4

30
Case 2:
Total Power available=897026541.3 KWh
Revenue Generated=1794.05 million Rupees
No. of turbines=12
Case 3:
Total Power available= 3027820085KWh
Revenue Generated= 6055.64 million Rupees
No. of turbines=5
Calculation Table:
Sr# Rollno. NetInflows InflowVol. Outflows UDO Surplus Deficit NetHead AvailablePower FirmYeild Sec.Yeild Energy Cost/kWh F.O.O(%)
Months Days (m^3/sec) MCM (m^3/sec) MCM MCM MCM (m) MW MW MW kWh MillionRupees Q(m^3/s) P(MW) ForQ
1 44 January 31 100 267.84 79.0272924 289.728 144 100.473 zzzz 0.000 74752211.77 149.504 87.494 111.238 8.333333
2 44 Febrary 28 130 314.496 87.4945023 243.072 144 111.238 10.765 74752211.77 149.504 81.661 103.823 16.66667
3 44 March 31 180 482.112 79.0272924 75.456 144 100.473 0.000 74752211.77 149.504 81.661 103.823 25
4 44 April 30 220 570.24 81.6615355 12.672 144 103.823 3.350 74752211.77 149.504 81.661 103.823 33.33333
5 44 May 31 250 669.6 79.0272924 112.032 144 100.473 0.000 74752211.77 149.504 81.661 103.823 41.66667
6 44 June 30 310 803.52 81.6615355 245.952 144 103.823 100.473 3.350 74752211.77 149.504 79.027 100.473 50
7 44 July 31 390 1044.576 79.0272924 487.008 144 100.473 0.000 74752211.77 149.504 79.027 100.473 58.33333
8 44 August 31 300 803.52 79.0272924 245.952 144 100.473 0.000 74752211.77 149.504 79.027 100.473 66.66667
9 44 September 30 230 596.16 81.6615355 38.592 144 103.823 3.350 74752211.77 149.504 79.027 100.473 75
10 44 October 31 170 455.328 79.0272924 102.24 144 100.473 0.000 74752211.77 149.504 79.027 100.473 83.33333
11 44 November 30 150 388.8 81.6615355 168.768 144 103.823 3.350 74752211.77 149.504 79.027 100.473 91.66667
12 44 December 31 110 294.624 79.0272924 262.944 144 100.473 0.000 74752211.77 149.504 79.027 100.473 100
Q&PinDesendingorderTime
557.568
Sr# Rollno. NetInflows InflowVol. Outflows OutflowVol Surplus Deficit NetHead AvailablePower FirmYeild Sec.Yeild Energy Cost/kWh F.O.O(%)
(Months) Days (m^3/sec) MCM (m^3/sec) MCM MCM MCM (m) MW MW MW kWh MillionRupees Q(m^3/s) P(MW) ForQ
1 44 January 31 100 267.84 194 519.6096 251.7696 164 280.903 0.000 208992177 417.984 244 417.93 8.33333
2 44 Febrary 28 130 314.496 194 469.3248 154.8288 164 280.903 0.000 188767128 377.534 244 417.93 16.6667
3 44 March 31 180 482.112 194 519.6096 37.4976 164 280.903 0.000 208992177 417.984 244 417.93 25
4 44 April 30 220 570.24 194 502.848 67.392 164 280.903 0.000 202250494 404.501 244 417.93 33.3333
5 44 May 31 250 669.6 244 653.5296 16.0704 194 417.930 137.027 310939581 621.879 219 336.438 41.6667
6 44 June 30 310 803.52 244 632.448 171.072 194 417.930 137.027 300909272 601.819 219 336.438 50
7 44 July 31 390 1044.576 244 653.5296 391.0464 194 417.930 137.027 310939581 621.879 219 336.438 58.3333
8 44 August 31 300 803.52 244 653.5296 149.9904 194 417.930 137.027 310939581 621.879 219 336.438 66.6667
9 44 September 30 230 596.16 219 567.648 28.512 174 336.438 55.535 242235269 484.471 194 280.903 75
10 44 October 31 170 455.328 219 586.5696 131.2416 174 336.438 55.535 250309778 500.620 194 280.903 83.3333
11 44 November 30 150 388.8 219 567.648 178.848 174 336.438 55.535 242235269 484.471 194 280.903 91.6667
12 44 December 31 110 294.624 219 586.5696 291.9456 174 336.438 55.535 250309778 500.620 194 280.903 100
Q&PinDesendingorderTime
280.903464

31
3.6 Graphs:
3.6.1 Power Duration Curve
Case 1:
Case 2:
0.000
200.000
400.000
600.000
800.000
1000.000
1200.000
1400.000
0.00 20.00 40.00 60.00 80.00 100.00 120.00
Power(MW)
Frquency Of Occurrence
Power Duration Curve
0
50
100
150
200
250
300
350
0.00 20.00 40.00 60.00 80.00 100.00 120.00
Power(MW)
Frequency Of Occurrence

32
Case 3:
3.6.2 Flow Duration Curves
Case 1
0.00
50.00
100.00
150.00
200.00
250.00
300.00
350.00
400.00
450.00
0.00 20.00 40.00 60.00 80.00 100.00 120.00
Discharge(m^3/s)
Flow Duration Curve
Flow Duration Curve
0.000
50.000
100.000
150.000
200.000
250.000
300.000
350.000
0.00 20.00 40.00 60.00 80.00 100.00 120.00
Power(MW)

33
Case 2
Case 3
0.000
50.000
100.000
150.000
200.000
0.00 20.00 40.00 60.00 80.00 100.00 120.00
Discharge(m^3/s)
Flow Duration Curve
Flow Duration Curve
0.000
20.000
40.000
60.000
80.000
100.000
120.000
140.000
160.000
180.000
200.000
0.00 20.00 40.00 60.00 80.00 100.00 120.00
Discharge(m^3/s)
Flow Duration Curve
Flow Duration Curve

34
3.6.3 Combined Graphs of all cases:
0
50
100
150
200
250
300
350
400
450
0 20 40 60 80 100 120
DischargeInDescendingOrder(cumecs)
F.O.O(%)
Flow Duration Curve
WithOut Storage With Storage(UDO) With Storage
0.00
200.00
400.00
600.00
800.00
1000.00
1200.00
1400.00
1600.00
0 20 40 60 80 100 120
PowerInDescendingOrder(MW)
F.O.O(%)
WithOut Storage With Storage(UDO) With Storage

35
3.7 Results:
No. of turbines:
Case 1=4
Case 2=12
Case3=5
3.8 Comments:
Available power is minimum in January and maximum in August.
o In case 1: The probability of occurrence of maximum power of 1515.06 MW is the lowest with
8.33% value While the probability of occurrence of 77.70 MW is maximum i: e is 100%.
o In case 2: The probability of occurrence of maximum power of 111.238MW is the lowest with
8.33% value While the probability of occurrence of 100.273MW is maximum i: e is 100%.
o In case 3: The probability of occurrence of maximum power of 417.93 MW is the lowest with
8.33% value While the probability of occurrence of 280.903 MW is maximum i: e is 100%.

36
Design No. 4
4 Estimation of Bed Load, Total Sediment load and Bed of
Reservoir.
4.1 Objective:
o Estimate the annual sediment load using Meyer-Peter & Muller’s Approach.
o Estimate the annual sediment load using Ackers & White’s Approach.
o Estimate the reservoir capacity if the flow is to be regulated at a uniform rate and using the
results obtained in (i) & (ii) estimate the Half-life of reservoir.
4.2 Related Theory:
4.2.1 Sediment Terminology
1. Sediment:
Fragmented material that originates from weathering of rocks and is transported by, suspended
in, or deposited by water.
2. Sediment Discharge:
It is defined as the amount of sediment passing any section per unit time.
3. Sediment Transport:
It is the amount of sediment (weight or volume) passing through a particular section of channel
per unit time (m3/s, kg/s, lb/s, metric-ton/s).

37
4. Sediment Yield:
The total sediment outflow from a watershed or a drainage area at a point of reference and in a
specified period of time. This is equal to sediment discharge from that drainage area
5. Bed Load:
Sediment that moves by saltation (jumping, rolling or sliding in the bed layer) is known as bed
load.
6. Bed Load Transport:
When the flow conditions satisfy or exceed the criteria for incipient motion, sediment particles
along the alluvial bed will start move.
If the motion of sediment is rolling, sliding or jumping along the bed, it is called Bed Load
Transport. Generally, the bed load transport for a river is about 5-25% of that in suspension.
However, for coarser material higher percentage of sediment may be transported as Bed Load.
7. Suspended Load:
Sediment that is transported by upward components of turbulence current and stays in
suspension for appreciable period of time.
8. Bed Material Load:
That part of total sediment discharge which is composed of grain sizes formed in the bed and in
the sand bed stream, it is equal to the transport capability of flow.
9. Wash Load/Fine Load:
That part of total sediment discharge which is composed of particle sizes finer than those
represented in bed and it is determined by available bank and up-slopes supply rates.
4.2.2 Total load transport:
1. Based on mode of transportation:
Total load = bed load + suspended load

38
2. Based on source of material being transported:
Total load = bed material load + wash load
4.2.3 Capacity Terminology
1. Capacity Inflow Ratio:
It is the ratio of half reservoir capacity to the summation of total inflow yield. It is used to
calculate sediment trapped efficiency.
2. Life of a Reservoir:
It is that period of time in which it fulfils its objective of storage. When half-life of the reservoir
is over its useful life is over.
3. Half-life of Reservoir:
Half-life of the reservoir is computed by the storage capacity of the reservoir and the sediment
trapped annually in the reservoir. So it depends on the sediment deposition as well the storage
capacity.
4. Trap Efficiency:
It is the percentage of sediment trapped in the reservoir for a certain time period. It is obtained
from the Brune’s curve which is a plot between efficiency and capacity inflow ratio.
4.2.4 Approaches used to estimate Bed load and Total sediment load:
1. Bed Load Transport
o DuBoy’s approach
o Shield’s approach
o Meyer-Peter approach
o Meyer-Peter and Muller’s approach
o Schoklistch’s approach
o Rottner’s approach
o Velocity approach

39
2. Bed form
o Probabilistic approach
o Stochastic approach
o Total Load Transport:
o Engelund & Hansen’s Approach
o Ackers and White’s Approach:
o Yang Approach
o Shen and Hung’s Approach
4.3 Problem Statement:
Estimate using following data:
o Bed load transport.
o Total sediment load
o Life of reservoir considering reservoir outflow as UDO
o Estimation of bed load (Meyer-Peter and Muller’s approach)
4.4 Procedure:
o After 14 years of research and analysis, Meyer-Peter and Muller (1948) transformed the
Meyer-Peter formula into Meyer-Peter & Muller’s formula.
o The coefficient Kr was determined by Muller’s as,
o Where, d90 = size of sediment for which 90% of the material is finer
d50=0.55mm
d90= 0.68 mm
So= 1:2000
Sp.wt. of water= 1 metric. Ton/m3
Kinematic viscosity of water= 1*10-6
m2
/s
Specific Gravity of particle=2.65

40
Annual bed load transport = 1001058177 Kgs
Estimation of total sediment load (Ackers and White’s Approach):
Time(t) Discharge(Q) Area(A) Depth(D) Width(B) Velocity(V) Kr Sr Ƴ×Sr×R 0.047(Ƴs-
Ƴ)d50
qb1 qb2 qb3
(weeks) (cumecs) m2 m m m/s mton/s/m (kg/s) (kg)
4 334 200 1 200 1.67 87.891 0.00036 0.00036 4.26525E-
05
0.000141 28.1507 68102126
8 454 260 1.3 200 1.7461538 87.891 0.00028 0.00036 4.26525E-
05
0.000141 28.2756 68404348
12 634 340 1.6 212.5 1.8647059 87.891 0.00024 0.00039 4.26525E-
05
0.000157 33.4169 80842219
16 774 430 1.9 226.316 1.8 87.891 0.00018 0.00034 4.26525E-
05
0.000127 28.6592 69332220
20 1124 590 2.5 236 1.9050847 87.891 0.00014 0.00035 4.26525E-
05
0.000132 31.0818 75193177
24 1694 840 4.1 204.878 2.0166667 87.891 8.1E-05 0.00033 4.26525E-
05
0.000121 24.7893 59970322
28 3364 1360 6.3 215.873 2.4735294 87.891 6.8E-05 0.00043 4.26525E-
05
0.00019 41.0092 99209516
32 4294 1470 7.1 207.042 2.9210884 87.891 8.1E-05 0.00058 4.26525E-
05
0.000307 63.6261 153924343
36 3564 1360 6.1 222.951 2.6205882 87.891 8E-05 0.00049 4.26525E-
05
0.000234 52.178 126229016
40 1064 570 5.9 96.6102 1.8666667 87.891 4.3E-05 0.00025 4.26525E-
05
7.46E-05 7.20431 17428662
44 804 440 2.8 157.143 1.8272727 87.891 0.00011 0.00031 4.26525E-
05
0.000107 16.8025 40648561
48 544 330 1.9 173.684 1.6484848 87.891 0.00015 0.00028 4.26525E-
05
9.33E-05 16.199 39188555
52 474 260 1.1 236.364 1.8230769 87.891 0.00038 0.00042 4.26525E-
05
0.000179 42.4046 102585112
sum 1001058177
Time(
t)
Discharge
(Q)
Area(
A)
Depth(
D)
Width(
B)
Velocity
(V)
q Shear
velocity(
U)
Fgr Ggr X qb1 qb2 qb3
(Wee
ks)
(cumecs) (m2) (m) (m) (m/s) (m3/s/
m)
(m/s) (mtons/s/
m)
(kg/s) (kg)
4 334 200 1 200 1.67 1.67 0.066773
086
0.7247
62
0.1883
554
0.0008
74
0.001459
503
291.90
06
70616591
3
8 454 260 1.3 200 1.74615
385
2.27 0.076133
032
0.7686
84
0.2219
206
0.0007
68
0.001742
865
348.57
31
84326800
5.8
12 634 340 1.6 212.5 1.86470
588
2.9835
29
0.084462
015
0.8214
04
0.2659
091
0.0007
37
0.002199
736
467.44
39
11308402
71
16 774 430 1.9 226.31
58
1.8 3.42 0.092040
347
0.8194
98
0.2642
483
0.0005
91
0.002020
095
457.17
94
11060083
73
20 1124 590 2.5 236 1.90508
475
4.7627
12
0.105577
519
0.8781
19
0.3177
486
0.0005
24
0.002497
543
589.42
02
14259254
44
24 1694 840 4.1 204.87
8
2.01666
667
8.2683
33
0.135205
194
0.9671
21
0.4085
757
0.0003
84
0.003174
489
650.38
31
15734068
07
28 3364 1360 6.3 215.87
3
2.47352
941
15.583
24
0.167599
115
1.1624
34
0.6486
714
0.0003
95
0.006158
231
1329.3
96
32160746
68
32 4294 1470 7.1 207.04
23
2.92108
844
20.739
73
0.177922
397
1.3125
44
0.8714
915
0.0004
9
0.010152
311
2101.9
57
50850552
84

41
Total Annual sediment load = 22232485179 kgs
Calculation of life of Reservoir:
4.6 Results
o Total Annual sediment Load= 22232485179 Kgs
o Half Capacity Of reservoir= 8506.27938 MCM
o Sum of inflow volumes=46259.9524MCM
o Capacity –Inflow ratio= 0.183880025
o Sediment Trapped efficiency=90% (brunes curve)
36 3564 1360 6.1 222.95
08
2.62058
824
15.985
59
0.164917
357
1.2013
78
0.7032
724
0.0004
54
0.007264
04
1619.5
24
39179516
78
40 1064 570 5.9 96.610
17
1.86666
667
11.013
33
0.162191
262
0.9628
05
0.4039
032
0.0002
4
0.002646
114
255.64
15
61844789
3.5
44 804 440 2.8 157.14
29
1.82727
273
5.1163
64
0.111732
744
0.8667
34
0.3069
655
0.0004
37
0.002233
787
351.02
36
84919636
5.2
48 544 330 1.9 173.68
42
1.64848
485
3.1321
21
0.092040
347
0.7746
34
0.2266
832
0.0004
91
0.001537
642
267.06
41
64608158
3.2
52 474 260 1.1 236.36
36
1.82307
692
2.0053
85
0.070032
203
0.7750
67
0.2270
313
0.0009
72
0.001948
306
460.50
88
11140628
93
sum 22232485
179
Time Q Inflow yield UDO Surplus Deficit
(weeks) (cumecs) (MCM) (MCM) (MCM) (MCM)
4 334 808.0128 3558.45711 -2750.444308
8 454 1098.3168 3558.45711 -2460.14031
12 634 1533.7728 3558.45711 -2024.68431
16 774 1872.4608 3558.45711 -1685.99631
20 1124 2719.1808 3558.45711 -839.27631
24 1694 4098.1248 3558.45711 539.66769
28 3364 8138.1888 3558.45711 4579.73169
32 4294 10388.0448 3558.45711 6829.58769
36 3564 8622.0288 3558.45711 5063.57169
40 1064 2574.0288 3558.45711 -984.42831
44 804 1945.0368 3558.45711 -1613.42031
48 544 1316.0448 3558.45711 -2242.41231
52 474 1146.7008 3558.45711 -2411.75631
SUM 46259.9424 17012.55876 -17012.55879

42
o Volume of sediment trapped=12.58 MCM/year
o Half-life of reservoir= years
4.7 Comments:
o Sediment Trapped efficiency is coming out to be 89% from both cases while the approaches
are different.
o Since the life of reservoir is coming in hundreds that showed the error of the observational
readings.

43
Design No: 5
5 Computation of GVF profile by standard step method.
5.1 Objective:
o To draw the water surface profile for gradually varied flow
o To compute the length parallel to the channel bed in which the flow is gradually varying.
5.2 Related Theory:
5.2.1 Gradually Varied Flow:
The gradually varied flow is the steady flow whose depth varies gradually along the length of the
channel. The definition signifies:
That the flow is steady; that the hydraulic characteristics of flow remain constant for the time
interval under consideration
That the streamlines are practically parallel; that hydrostatic distribution of pressure prevails over
the channel section
5.2.2 Assumptions for gradually varied flow:
o The theories thus developed practically all hinge on following assumptions:
o The head loss at a section is the same as for a uniform flow having the velocity and hydraulic
radius of the section.
o The uniform flow formula (Chezy, Manning) may be used to evaluate the energy slope of
gradually varied flow at a given channel section and the corresponding coefficient of roughness
developed primarily for uniform flow is applicable to the varied flow.
o The slope of the channel is small so that the depth of flow is the same whether the vertical or
normal (to a channel bottom) direction is used.
o The channel is prismatic; that is, the channel has constant alignment and shape.
o The roughness coefficient is independent of the depth of flow and constant throughout the
channel reach under consideration.

44
5.2.3 Gradually Varied Flow Profiles:

45

46
1. Flow over a weir (mild slope):
2. Flow under a sluice gate – (a) mild slope:
3. Flow under a sluice gate – (b) steep slope:

47
4. Flow from a reservoir – (a) mild slope:
5. Flow from a reservoir – (b) steep slope:
6. Flow into a reservoir (mild slope):

48
7. Free over fall (mild slope):
5.2.4 Limitations of gradually varied flow equation:
o Steady State Flow
o One Dimensional (can only calculate average cross-sectional water velocity)
o General form of the Gradually Varied Flow equation is
Where:
So = Bottom slope, positive in the downward direction
Sf = Friction slope, positive in the downward direction
y = Water depth, measured from culvert bottom to water surface
x = Longitudinal distance, measured along the culvert bottom
Fr = Froude number
o The Friction slope is approximated from Manning’s Equation
Where:
n = Manning’s roughness coefficient
V = Average cross section velocity
Φ = Constant equal to 1.49 for English units and 1.00 for SI units.
R = Hydraulic radius, (Wetted Area / Wetted Perimeter)

49
5.2.5 Methods to Compute Gradually Varied Flow Profiles:
There are several methods to obtain surface water profile. These are
o Direct Integration
o Numerical Integration
o Direct Step Method
o Graphical Integration
o Numerical/Computer Methods
1. Direct Integration Method:
It is based on the direct integration of the dynamic equation for gradually varied flow, which forms
the bases for existing methods of computing flow profiles. In these methods, a long reach for which
the profile length is needed gets divided into several subsections, to ensure that the hydraulic
exponents do not vary very much in the subsections. Since the proposed analytical method does
not use the hydraulic exponent in its development, the flow profiles can be computed in one step
and one can still get accurate results. The results of the profile computations based on existing
methods are compared with the corresponding results of the present method. The results find direct
application in hydraulic engineering practice, where flow profile lengths are needed for design
purposes.
2. Numerical Integration Method:
The GVF differential equation does not have an analytical solution. Therefore, Fish Xing uses
numerical integration to generate a water surface profile. Numerical integration is a technique of
dividing the channel, or culvert, into numerous short reaches and then performing the computations
from one end of the reach to the other
Fish Xing primarily uses the Standard Step Method of numerical integration. The following form
of the equation is used:
Where:
∆E = Change in specific energy from one end of the reach to the other
Sfave = Average friction slope across the reach
∆x = Longitudinal distance from one end of the reach to the other
y = Depth of water
Q = Flow rate
g = Gravitational acceleration
A = Wetted cross-sectional area

50
Since the friction slope and wetted area are functions of depth, solving for depth at a given distance
(x) requires an iterative solution. Fish Xing uses a bisection method to find the solution.
5.3 Procedure
o Calculate the required data from the assignment page provided.
o Calculate the normal depth and critical depth for the provided data.
o Take upstream water level as 1.02 time’s normal depth and at downstream as 2.2-time normal
depth.
o Record the location of measured channel cross sections and the trial water surface elevation,
z, for each section. The trial elevation will be verified or rejected based on computations of the
step method.
o Apply the standard step method to compute the energy head at different stations.
o Draw the bed, water surface and energy profiles for the calculated data.

51

52
5.5 GVF Profile:
5.6 Comments:
We have many approaches to follow but we used the standard step method because it is convenient
to use.
0
10
20
30
40
50
60
0 500 1000 1500 2000 2500 3000 3500 4000 4500
Elevaltion(m)
x (m)
GVF Profile
x Vs y x Vs H x vs Z

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