final report of group 6 sundarijal hpp
DESCRIPTION
Final Report of Group 6 Sundarijal HPPTRANSCRIPT
FINAL REPORT ON
RUM OF SUNDARIJAL HYDOPOWER PLANT
A fourth year mini project for the partial fulfillment of requirement of Bachelor’s Degree in
Civil Engineering (CIEG 406)
PROJECT MEMBERS:
GROUP: 6
Biplav Acharya (Roll No. 01)
Ashish Dangal (Roll No. 12)
Mingma Lama (Roll No. 31)
Radheshyam Mandal (Roll No. 32)
Rishab Nakarmi (Roll No. 33)
Pratik Shahi (Roll No. 47)
Sagun Shrestha (Roll No. 53)
SUBMITTED TO:
DEPARTMENT OF CIVIL AND GEOMATICS ENGINEERING
Prof. Dr. Ing. Ramesh Kumar Maskey
Project In-charge
January 4, 2014
KATHMANDU UNIVERSITY SCHOOL OF ENGINEERING
DEPARTMENT OF CIVIL AND GEOMATICS
ENGINEERING
2
ACKNOWLEDGEMENT
We would like to thank Prof. Dr. Ramesh Kumar Maskey, for providing us an opportunity to
work on this project and helping in various aspects during consultation. We would also like to
thank the staffs of DOCGE and friends for their unending support and encouragement.
3
ABSTRACT
Sundarijal Hydropower Plant, although being an old plant is generating 640kW, its installed capacity. The
plant is already in the process of RUM by NEA which is on its way for increase in power generation. The
RUM project carried out by us, a team of 7 students of Fourth Year Civil Engineering program has
detected some components that have degraded and has given suitable design, drawings and suggestions.
The hydropower plant is found to be optimistic in terms of further development and more hydropower
generation.
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Table of Contents ABSTRACT ............................................................................................................................................................. 3
ACRONYMS ........................................................................................................................................................... 7
1. INTRODUCTION ................................................................................................................................................. 8
2. PROJECT AREA ................................................................................................................................................... 9
2.1 History ......................................................................................................................................................... 9
2.2 Geography ................................................................................................................................................. 10
2.3 Climate ...................................................................................................................................................... 10
3. THEORY ........................................................................................................................................................... 11
3.1 Rehabilitation ............................................................................................................................................ 11
3.2 The Bathtub Curve .................................................................................................................................... 12
3.3 Levelling: ................................................................................................................................................... 12
3.4 Bowditch Rule: .......................................................................................................................................... 13
3.5 Penstocks: ................................................................................................................................................. 14
3.6 Penstock Alignment .................................................................................................................................. 14
3.7 Gross Head (H) and Net Head (h): ............................................................................................................ 15
3.8 Firm Power and Secondary Power: ........................................................................................................... 15
3.9 Flow Duration Curve: ................................................................................................................................ 15
3.10 Mass Flow Curve ..................................................................................................................................... 16
3.11 Support Piers ........................................................................................................................................... 16
3.12 Energy and Hydraulic Grade Lines: ......................................................................................................... 16
The Bernoulli Equation ............................................................................................................................... 17
4. RATIONALE ...................................................................................................................................................... 17
5. SCOPE OF THE PROJECT .................................................................................................................................. 18
6. OBJECTIVES ..................................................................................................................................................... 18
7. METHODOLOGY .............................................................................................................................................. 18
8. Field Measurement Of Head Of Sundarijal HPP .......................................................................................... 19
8.1 Height Difference From Powerhouse To Dam Site ................................................................................... 19
8.2 Height Difference From Dam Site To Powerhouse ................................................................................... 22
8.3 Correction By Bowditch’s Method ............................................................................................................ 25
9. FIELD MEASUREMENT OF DISCHARGE............................................................................................................ 30
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9.1 Determination of Cross Section ................................................................................................................ 30
9.2 Determination of Velocity ......................................................................................................................... 32
9.3 Discharge .................................................................................................................................................. 32
9.4 Measurement of discharge from canal ..................................................................................................... 32
9.5 Flow Duration Curve ................................................................................................................................. 33
9.5.1 MIP Method ....................................................................................................................................... 33
9.5.2 Flow Duration Curve .......................................................................................................................... 34
9.6 Total Discharge ......................................................................................................................................... 35
10. FINDING HYDROPOWER POTENTIAL USING OBTAINED FIELD INFORMATION ............................................. 36
10.1 Design of penstock for that hydropower potential ................................................................................ 36
10.2 Penstock Alignment ................................................................................................................................ 37
10.3 Calculation of major and minor losses .................................................................................................... 38
10.3.1 Calculation of friction factor ............................................................................................................ 38
10.3.1 Calculation of head loss ................................................................................................................... 39
10.4 Remarks .............................................................................................................................................. 39
11 CALCULATION OF FIRM POWER AND SECONDARY POWER .......................................................................... 40
12. CALCULATION OF FLOW MASS CURVE ......................................................................................................... 42
13 .DESIGN OF SUPPORT PIER ............................................................................................................................ 43
13.1 Design ..................................................................................................................................................... 43
13.2 Stability Analysis ..................................................................................................................................... 47
13.3 Cost Estimation ....................................................................................................................................... 48
14. INSPECTION WORKS...................................................................................................................................... 49
15. PUBLIC CONSULTATION ................................................................................................................................ 50
16. PROJECT SCHEDULE ...................................................................................................................................... 51
17. OUTCOMES ................................................................................................................................................... 52
18. LIMITATIONS OF THE PROJECT ..................................................................................................................... 52
19. CONCLUSION AND RECOMMENDATIONS ..................................................................................................... 52
20. REFERENCES .................................................................................................................................................. 53
PICTORIAL HIGHLIGHTS ....................................................................................................................................... 54
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LIST OF FIGURES
Figure 1 Location of Sundarijal in Nepal ............................................................................................................... 9
Figure 2 View of Bagmati from Sundarijal Source: Wikipedia.org ...................................................................... 10
Figure 3 The figure illustrates how energy production is lost over time. The Upgrade vs Life extension .......... 11
Figure 4 Bathtub Curve ....................................................................................................................................... 12
Figure 5 Differential Levelling ............................................................................................................................. 13
Figure 6 Cross Section A-A of river...................................................................................................................... 30
Figure 7 Cross Section B-B of River ..................................................................................................................... 31
Figure 8 Flow Duration Curve ............................................................................................................................. 34
Figure 9 Penstock Alignment .............................................................................................................................. 37
Figure 10 Moody Diagram .................................................................................................................................. 38
Figure 11 Flow Mass Curve ................................................................................................................................. 42
Figure 12 Cross Section of Penstock ................................................................................................................... 44
Figure 13 Support pier elevation with saddle and penstock .............................................................................. 45
Figure 14 Cross section of penstock resting on support pier ............................................................................. 46
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ACRONYMS ASME – American Society of Mechanical Engineers
BM – Bench Mark
HPP – Hydropower Power Plant
JNN – Journal of Nanoscience and Nanotechnology
MIP – Medium Irrigation Project
RUM – Rehabilitation Upgradation and Modernization
USBR – The United States Bureau of Reclamation (USBR)
VDC – Village Development Committee
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1. INTRODUCTION Sundarijal HPP is the second oldest hydropower established in Nepal which lies in Sundarijal VDC named
after Hindu goddess ‘Sundarimai’. The VDC touches Nuwakot and Sindhupalchowk district and is located
in Shivapuri National Park at the north of Kathmandu Valley. It is 15 km northeast from the centre of
Kathmandu. The climate is of Temperate type. During summer, the temperature is 25.5 ˚ C in average and
temperature drops down to 0 ˚ C during winter. Tamangs, Chheteris and Brahmins are the major ethnic
group of this region. The major religion here is Buddhism.
With installed capacity of 640 kW and annual design generation of 4.77 GWh was commissioned in 1934
AD in a grant from British government.The powerhouse lies near Sundarijal Buspark. Initially, there were
three units of turbines; one of 600kW and two of 320kW. Due to mechanical failure, the larger one was
shut down.
The salient features of Sundarijal HPP is listed below:
Type Run of River
Location Sundarijal, Kathmandu
Installed capacity 640 kW
Annual average energy 4.77 GWh
Maximum net head 750 ft. (228.6m)
Penstock 1700 m long, 0.61 m dia.
Turbine
Number and Type
Rated output
Rated Speed
2, Horizontal Pelton
485 kW
900 rpm
Generator
Rated output
Rated voltage
Rated frequency
Power factor
377 kVA
3.3 kV
50 Hz
0.85
Power transformer 3.3/11 kVA, 2 Nos.
Transmission line 11 kV
Table 1: SAILENT FEATURES OF SUNDARIJAL HYDROPOWER STATION
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2. PROJECT AREA
Figure 1 Location of Sundarijal in Nepal
Country: Nepal
Zone Bagmati Zone
District: Kathmandu District
Area
Total: 5.18 km2 (2.00 sq mi)
Population (2001)
Total: 2,586
Density: 500/km2 (1,300/sq mi)
Time zone: Nepal Time (UTC+5:45)
Postal code: 44603 Area code(s): 01
Sundarijal is a village development committee in Kathmandu District in the Bagmati Zone of central
Nepal.
2.1 History The VDC was named after the Hindu goddess, Sundarimai. A temple is dedicated to the deity in
Sundarijal. In 1960, the Sundarijal Military Detention Camp was the location of Nepali Congress leaders
B.P. Koirala (the Prime Minister), Ganesh Man Singh, Krishna Prasad Bhattarai, Diwan Singh Rai, Ram
Narayan Mishra, Yogendra Man Sherchan, and Jaman Singh Gurung. They were held without trial for
eight years due to their participation in a 1960 coup.
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2.2 Geography Sundarijal is located 15 kilometres (9 mi) northeast of Nepal's capital, Kathmandu. It is west of
Gagalphedi, east of Nayapati and Baluwa, and north of Aalapot. The VDC touches Nuwakot and
Sindhulpalchok Districts to the north.
Sundarijal covers an area of 5.18 square kilometres (2 sq mi). The Bagmati River flows through the VDC,
where it is joined by the Shyalmati and Nagmati Rivers. Largely hilly in its terrain with few flat areas, the
VDC is covered by forests. Shivapuri National Park covers large amounts of the Sundarijal.
Figure 2 View of Bagmati from Sundarijal Source: Wikipedia.org
2.3 Climate The climate of Sundarijal is temperate. The average for the summer is 25.5˚C while that for the winter is
0˚C.
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3. THEORY
3.1 Rehabilitation
Hydroelectric station rehabilitation covers a broad set of activities, including repairing/replacing
components, upgrading generating capability and availability, realigning services to meet market
opportunities and new market requirements and modifying the management of water resources to enhance
ecosystems. In the current study, rehabilitation is focused on the major electrical and mechanical
equipment associated with power generation, namely the turbine and generator. Other components would
be included in most rehabilitation projects and would contribute to the overall cost but major civil works
changes (with the possible exception of
draft tube modifications) are excluded.
Rehabilitation can start with the
replacement of equipment on a “like for
like” basis where there is minimum effort
to enhance the overall output of the station.
The primary objective of this is to provide
“life extension” to the existing facilities
and restore their initial performances. In
contrast it can often be justified to include
an “upgrade” of the equipment (efficiency,
output) which yields greater output but at
increased costs which is justified by the
additional revenue over service life of the
equipment. This study examines both of
these investment scenarios. Non-structural
optimization, such as improved operation rules based on improved hydrology, timing of releases in
cascades etc has not been considered.
Project Expansion
Hydroelectric generating stations have been known to have service lives of up to 100 years and in some
instances even longer. Where the service life is long then it is quite likely that the station may not be
developed to its economic potential based on today’s energy and capacity values and equipment cost and
performance. In such instances an increase in station capacity (Project Expansion) by installing
additional generating units can be justified. In most cases significant increases in station capacity will
require installation of additional units, which if not foreseen and prepared for in the original
design/construction will likely require major civil works. Such cases of project expansion are not
covered (except in passing) in this report.
Project Redevelopment
In projects where the residual service life is too short to justify Rehabilitation or Project Expansion,
Project Redevelopment can be considered. In this scenario the civil works (potentially a dam and power
facilities) is redeveloped with completely new generating equipment. This scenario is not considered in
this study since it, in most cases, requires extensive site-specific engineering studies including
environmental and sustainability assessments which cannot be treated in a broad based manner as is being
done for the current study. (Goldberg & Lier)
Figure 3 The figure illustrates how energy production is lost over time. The Upgrade vs Life extension
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3.2 The Bathtub Curve
The bathtub curve is widely used in reliability engineering. It describes a particular form of the hazard
function which comprises three parts. The first part is a decreasing failure rate, known as early failures. The
second part is a constant failure rate, known as random failures. The third part is an increasing failure rate,
known as wear-out failures. In less technical terms, in the early life of a product adhering to the bathtub
curve, the failure rate is high but rapidly decreasing as defective products are identified and discarded, and
early sources of potential failure such as handling and installation error are surmounted. In the mid-life of
a product—generally, once it reaches consumers—the failure rate is low and constant. In the late life of the
product, the failure rate increases, as age and wear take their toll on the product. Many consumer product
life cycles strongly exhibit the bathtub curve, such as computer processors.
(Bathtub curve, 2014)
3.3 Levelling:
Direct leveling
This method of leveling uses the measuredvertical distance to carry elevation from a knownpoint to an
unknown point. Direct leveling is themost precise method of determining elevation andyields accuracies
of third or higher orders. Whenthis method is specified for lower accuracysurveys, direct leveling is
sometimes referred toas “spirit” or “fly” levels. Fly levels are levelingoperations used to rerun original
levels to makesure that no mistake has been made. Fly levelsuse a shorter route and smaller number of
turningpoints than the original survey. Let’s take a lookat some of the processes involving direct leveling.
Figure 4 Bathtub Curve
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Differential Leveling
Differential leveling (also called direct leveling) is generally used in determining elevations of points to
establish a chain or network of BMs for future use. It requires a series of instrument setups along the
survey route; and for setup, a horizontal line of sight is established, using a sensitive level.
Some terminology used in Levelling:
Set: The location of the level. (where it is set-up)
Bench Mark (BM): A permanent point of known elevation.
Temporary Bench Mark (TBM): A point of known elevation.
Turning Point (TP): An intervening point between BMs or TBMs upon which a backsight and a foresight
are taken.
Backsight (BS): A rod reading taken by "looking back" at a point of known elevation such as a BM or TP.
Foresight (FS): A rod reading taken when "looking ahead" at a point where you want to determine its
elevation, such as a TP, TBM or BM.
Height of Instrument (HI): The elevation of the line of sight in the telescope of the level.
Balancing of Sights: The rod person keeps track of the distance of each FS and BS taken and tries to keep
them equal.
Closed Circuit: A complete trace of the line of sight of the instrument back to the beginning point.
Closure: The difference between beginning and ending elevations.
3.4 Bowditch Rule:
The Bowditch's method is used when both the linear and angular measurements are compatible to each
other, i.e., they are of equal precision. The corrections may be applied either analytically or may be
carried out graphically. This method of balancing of traverse is widely prevalent and most commonly
used. It is based on the assumption that angles (bearings) are observed to the same degree of precision
that distances can be measured.
Where, l=length of the current time,
∑l=sum of the traverse line lengths
∆L=latitude of the current line
Where, ∆D=departure of the current line
Figure 5 Differential Levelling
Ll
lCorrLat
Dl
lCorrDep
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3.5 Penstocks: A penstock is a pipe that conveys the flow from the forebay or surge tank to the turbine. Penstocks are
designed to carry water to the turbines with the least possible loss of head consistent with the overall
economy of the project. These are pressurized water conduits which convey water to the turbines from
free surfaces.
Design of penstock pipe:
Using USBR formula,
Veco=0.125√2gH
D=√(4Q/πv)
Sarkaria Formula,
D = 0.62 P0.35
H0.65
From JNN Guideline, D=(5.2Q3/H)1/7
For thickness of penstock pipe:
Pressure inside Penstock (p) = ρg (H+H0) = kg/cm2
Where, H = static head ; H0= dynamic head = v2/2g
t= pD/2σaη + ε
As per ASME code:
t= pR/(σaη-0.6 p) + 0.15
tmin= D/ 288
tmin= (D+200)/400
3.6 Penstock Alignment For the most economical alignment of pipeline, investigation of site must be done and make various
layouts on topographic maps. Estimate materials quantities for each layout and evaluation of its
constructability must be done.
When making the layouts, the penstock should e located on stale foundation sites such as along a ridge or
a bench that has been cut into the mountainside, avoiding of troublesome sites such as underground water
courses, landfill, fault zones and potential slide area is quite important. To minimize costly anchors and
costly pipe transitions sections, vertical bends, horizontal ends, and changes in diameter should be
combined in a way to have them at the same location.
Selection of the alignment at site should be based on the following criteria:
Forebay/ surge tank location
Ground slope
Minimum number of bends
Space for powerhouse area
Stability
Other site specific conditions
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3.7 Gross Head (H) and Net Head (h): The gross head is the difference between the water level in the headrace and the water level in the tailrace.
For storage plant, gross head (H) is the difference in water level in the reservoir and the water level in the
tailrace. For run-of river plant, it is a difference in water level in the point of diversion of water and water
level at the point where the water is returned back to river.
Net head is the head available for the turbine. It is equal to the difference of total head at the point of
entry and at the point of exit of the turbine. This includes the respective pressure and velocity pressure
and velocity head at both places.
For impulse turbine, Net head, h=H-Z-hf ; where, hf is headloss
3.8 Firm Power and Secondary Power:
The power, which is insured to a consumer at any time of the day, is known as firm power. Firm power is
completely dependable and available 100% of time. Such power corresponds to minimum stream flow.
Such power can e increased by the use of pondage so that greater minimum flow is available for 100% of
time.
The secondary power is the amount of power, which is excess of the firm power. It is also called surplus
or non-firm power. The plant can deliver the secondary power only for a part of a year. It is
comparatively less valuable and useful in an interconnected system of power plants.
3.9 Flow Duration Curve:
A graphical representation of runoff is the flow duration curve. It has discharge plotted on the Y-axis and
the percentage of time duration for which that magnitude (or move) is available on X-axis.
Flow duration curve are used in assessing the dependability of the discharge and also used in assessing
dependable power in runoff river plant with or without pondage.
Flow –duration curves find considerable use in water resources planning and development activities.
Some of the important uses are:
In evaluating various dependable flows in the planning of water resources engineering projects.
Evaluating the characteristics of the hydro power potential of a river
Designing of the drainage system.
In flood-control studies.
Computing the sediment load and dissolved solid load od stream.
Comparing the adjacent catchment with the view to extend the stream flow data.
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3.10 Mass Flow Curve
The flow mass curve is a plot of the cumulative discharge volume against time plotted in chronological
order. The ordinate of the mass curve, V at any time t is thus
V=∫ 𝑄 𝑑𝑡𝑡
0
Where t0 is the time at the beginning of the curve and Q is the discharge rate. The slope of the mass curve
at any point represents 𝑑𝑉
𝑑𝑡=Q=rate of flow at that instant.
3.11 Support Piers
Support piers are required along the straight sections of exposed penstock between anchor blocks.
The maximum spacing of support piers to avoid overstressing the pipe is generally 5m. Thin-wall plain
pipe can buckle at the support piers with relatively short spans. In this case the permissile span can be
increased by welding a wear plate to the pipe at each support. This may be economical for pipes larger
than 300 mm diameter. Corners of wear plates should e cut with a radius, to avoid stress concentrations.
Note that a wear plates is also required where the pipe leaves an anchor lock, if the span to the first
support pier exceeds that allowed for plain pipe. It is usually not economical to increase the pipe wall
thickness in order to increase the support pier spacing, but this should be considered where the cost of
support piers is significant.
A 1400 bearing area from the centre of the penstock diameter should be provided to support the penstock
pipe. Placing a steel saddle plate above the support pier where the penstock pipe rests along with a 3mm
thick tar paper minimizes frictional effect and increases the useful life of the pipe. C- clamps may also be
provided to protect the pipe from vandalism and a sideways movement, but there must be a gap between
the surface of the pipe and the C- clamp, so that axial forces are not transferred to the support pier.
3.12 Energy and Hydraulic Grade Lines:
The energy grade line (EGL) and the hydraulic grade line (HGL) provide a graphical interpretation of
Bernoulli's equation. The EGL represents the total head available with respect to a chosen datum.
The EGL is a constant for frictionless flow where no work or heat is associated with the process. On the
other hand, the HGL is the sum of static pressure and elevation head.
Sometimes, this is also referred as the piezometric head and is the height a fluid column would rise in a
piezometer.
17
The Bernoulli Equation
For steady, inviscid, incompressible flow the total energy remains constant along a stream line as
expressed through the Bernoulli Equation:
p + 1/2 v2 + h = constant along a streamline
where:
p = static pressure (relative to the moving fluid)
ρ = density
ϒ= specific weight
v = flow velocity
g = acceleration of gravity
h = elevation height
Each term of this equation has the dimension force per unit area - psi, lb/ft2 or N/m2.
For a fluid flowing without any losses due to friction (major losses) or components (minor losses) - the
energy line would be at a constant level. In a practical world the energy line decreases along the flow due
to losses.
4. RATIONALE The efficiency of all structures and machines decrease after they’ve been used for a long time. Ignoring
this aspect will not only decrease the performance of the power plant but the risk of the plant will start to
increase exponentially at a certain time and the plant may shut down due to uncontrollable problems in
the future. Therefore, rehabilitation of the components of the power plant has to be done while the risk
doesn’t escalate.
Sundarijal Hydropower Plant has been in operation since 1934 AD and has had minor upgrades to some
electrical and mechanical components during its operational life. The penstock and station flows are part
of the water supply system to Kathmandu Valley and are looked after by Kathmandu Upatyaka Khanepai
Limited (KUKL). Therefore, it is a good idea to examine the civil components if they need rehabilitation
or upgrades before the risks escalate.
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5. SCOPE OF THE PROJECT The scope of this project is to study Sundarijal HPP under the constraints of hydrology, engineering
survey and civil engineering under hydropower engineering. However, the study of catchment area and
the its basin isn’t studied. Similarly, the study of rocks, mines, minerals and other geological aspects are
out of the scope.
6. OBJECTIVES 1. To study the hydropower systems of Sundarijal HPP
2. To identify the components of Sundarijal Hydropower Plant this needs Rehabilitation, Maintenance
and Up gradation (RUM)
3. Recommend RUM measures and design/redesign necessary structures
4. To check the hydropower potential of the HPP
7. METHODOLOGY Desk Study
Desk study covers various literature reviews, project planning etc. Required information was
gathered via various sources and results from it were implemented at various steps of our
project implementation.
Consultation and field visits
After consultation with faculties, friends, local people and information gathered from the
desk study and the site we planned the project.
Design
Based on our survey and requirements, we made calculations of head of the hydropower,
discharge, flow duration curve and designed alternate alignment of penstock. Support pier
was designed which can be used to construct in place of the displaced piers at the site.
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8. Field Measurement of Head of Sundarijal HPP
8.1 HEIGHT DIFFERENCE FROM POWERHOUSE TO DAM SITE
WL-M 0.885
SN BS FS RISE FALL RL HD CD
T M B T M B 999.015
1 1.155 1.105 1.055 1000.000 30 30
2 1.165 0.94 0.715 2.29 2.19 2.09 0 1.085 998.915 89 119
3 1.435 1.395 1.355 1.895 1.675 1.455 0 0.735 998.180 31 150
4 1.69 1.61 1.53 1.22 1.105 0.99 0.29 0 998.470 25 175
5 3.99 3.91 3.83 1.15 1.105 1.06 0.505 0 998.975 21 196
6 3.18 3.15 3.12 0.87 0.845 0.82 3.065 0 1002.040 9 205
7 2.67 2.645 2.62 0.525 0.51 0.495 2.64 0 1004.680 8 213
8 3.235 3.205 3.175 0.25 0.235 0.22 2.41 0 1007.090 9 222
9 3.94 3.905 3.87 0.33 0.315 0.3 2.89 0 1009.980 11 233
10 3.41 3.375 3.34 0.245 0.225 0.205 3.68 0 1013.660 10 243
11 3.855 3.82 3.785 0.305 0.29 0.275 3.085 0 1016.745 11 254
12 3.55 3.435 3.32 0.61 0.59 0.57 3.23 0 1019.975 59 313
13 3.37 3.31 3.25 1.7 1.52 1.34 1.915 0 1021.890 14 327
14 3.6 3.56 3.52 0.75 0.74 0.73 2.57 0 1024.460 11 338
15 3.485 3.445 3.405 0.585 0.57 0.555 2.99 0 1027.450 12 350
16 3.63 3.59 3.55 0.23 0.21 0.19 3.235 0 1030.685 12 362
17 3.62 3.58 3.54 0.24 0.22 0.2 3.37 0 1034.055 11 373
18 3.545 3.505 3.465 0.24 0.225 0.21 3.355 0 1037.410 14 387
19 3.32 3.275 3.23 0.47 0.44 0.41 3.065 0 1040.475 14 401
20 3.235 3.195 3.155 0.22 0.195 0.17 3.08 0 1043.555 14 415
21 3.455 3.405 3.355 0.27 0.24 0.21 2.955 0 1046.510 14 429
22 3.26 3.21 3.16 0.53 0.51 0.49 2.895 0 1049.405 15 444
23 3.37 3.315 3.26 0.32 0.295 0.27 2.915 0 1052.320 20 464
24 3.81 3.735 3.66 0.46 0.415 0.37 2.9 0 1055.220 22 486
25 3.02 2.97 2.92 0.31 0.275 0.24 3.46 0 1058.680 17 503
26 3.565 3.505 3.445 0.665 0.63 0.595 2.34 0 1061.020 24 527
27 2.915 2.775 2.635 0.395 0.335 0.275 3.17 0 1064.190 37 564
28 3.88 3.805 3.73 0.16 0.115 0.07 2.66 0 1066.850 23 587
29 3.33 3.25 3.18 0.13 0.09 0.05 3.715 0 1070.565 22 609
30 2.8 2.75 2.7 0.52 0.49 0.45 2.76 0 1073.325 17 626
31 2.84 2.82 2.8 0.575 0.54 0.505 2.21 0 1075.535 9 635
32 2.56 2.495 2.43 0.275 0.25 0.225 2.57 0 1078.105 16 651
33 2.78 2.73 2.68 0.235 0.22 0.205 2.275 0 1080.380 18 669
34 3.335 3.305 3.275 0.28 0.24 0.2 2.49 0 1082.870 9 678
35 3.755 3.675 3.595 0.11 0.095 0.08 3.21 0 1086.080 27 705
20
36 3.145 3.075 3.005 0.2 0.145 0.09 3.53 0 1089.610 26 731
37 1.955 1.855 1.755 0.265 0.205 0.145 2.87 0 1092.480 28 759
38 2.84 2.8 2.76 0.44 0.4 0.36 1.455 0 1093.935 15 774
39 2.95 2.92 2.89 0.325 0.29 0.255 2.51 0 1096.445 10 784
40 2.92 2.89 2.86 0.365 0.345 0.325 2.575 0 1099.020 12 796
41 2.97 2.94 2.91 0.23 0.2 0.17 2.69 0 1101.710 12 808
42 3.185 3.15 3.115 0.1 0.07 0.04 2.87 0 1104.580 13 821
43 3.665 3.615 3.565 0.17 0.14 0.11 3.01 0 1107.590 15 836
44 2.54 2.49 2.44 0.06 0.035 0.01 3.58 0 1111.170 20 856
45 3.42 3.37 3.32 0.46 0.41 0.36 2.08 0 1113.250 14 870
46 3.66 3.63 3.6 0.3 0.28 0.26 3.09 0 1116.340 56 926
47 3.615 3.58 3.545 0.75 0.5 0.25 3.13 0 1119.470 9 935
48 3.38 3.355 3.33 0.23 0.22 0.21 3.36 0 1122.830 12 947
49 3.16 3.115 3.08 0.145 0.11 0.075 3.245 0 1126.075 11 958
50 2.685 2.645 2.605 1.2 1.185 1.17 1.93 0 1128.005 12 970
51 2.89 2.865 2.84 0.22 0.2 0.18 2.445 0 1130.450 8 978
52 2.86 2.845 2.83 0.16 0.145 0.13 2.72 0 1133.170 5.5 983.5
53 3.76 3.705 3.65 0.155 0.145 0.13 2.7 0 1135.870 15 998.5
54 3.99 3.945 3.9 0.31 0.29 0.27 3.415 0 1139.285 14 1012.5
55 3.735 3.69 3.645 0.15 0.125 0.1 3.82 0 1143.105 12 1024.5
56 3.735 3.695 3.655 0.42 0.405 0.39 3.285 0 1146.390 10 1034.5
57 3.9 3.865 3.83 0.455 0.445 0.435 3.25 0 1149.640 10 1044.5
58 3.025 3 2.975 0.37 0.355 0.34 3.51 0 1153.150 10 1054.5
59 3.795 3.77 3.745 0.165 0.14 0.115 2.86 0 1156.010 9 1063.5
60 2.63 2.615 2.6 0.14 0.12 0.1 3.65 0 1159.660 6 1069.5
61 3.95 3.915 3.88 0.11 0.095 0.08 2.52 0 1162.180 11 1080.5
62 3.37 3.34 3.31 0.24 0.22 0.2 3.695 0 1165.875 9 1089.5
63 3.625 3.59 3.555 0.19 0.175 0.16 3.165 0 1169.040 12 1101.5
64 3.985 3.935 3.885 0.24 0.215 0.19 3.375 0 1172.415 15 1116.5
65 3.615 3.53 3.445 0.085 0.06 0.035 3.875 0 1176.290 22 1138.5
66 3.83 3.795 3.76 0.09 0.065 0.04 3.465 0 1179.755 10 1148.5
67 3.41 3.38 3.35 0.2 0.185 0.17 3.61 0 1183.365 10 1158.5
68 3.465 3.43 3.395 0.1 0.08 0.06 3.3 0 1186.665 10 1168.5
69 3.835 3.795 3.755 0.23 0.215 0.2 3.215 0 1189.880 11 1179.5
70 3.36 3.335 3.31 0.11 0.095 0.08 3.7 0 1193.580 10 1189.5
71 3.39 3.345 3.3 0.075 0.05 0.025 3.285 0 1196.865 15 1204.5
72 3.715 3.675 3.635 0.11 0.08 0.05 3.265 0 1200.130 12 1216.5
73 3.815 3.77 3.725 0.205 0.185 0.165 3.49 0 1203.620 14 1230.5
74 3.3 3.255 3.21 0.195 0.17 0.145 3.6 0 1207.220 18 1248.5
75 3.055 2.96 2.865 0.285 0.24 0.195 3.015 0 1210.235 25 1273.5
76 3.665 3.64 3.615 0.25 0.22 0.19 2.74 0 1212.975 9 1282.5
21
77 3.57 3.54 3.51 0.255 0.235 0.215 3.405 0 1216.380 20 1302.5
78 0.31 0.24 0.17 0.53 0.46 0.39 3.08 0 1219.460 47 1349.5
79 1.525 1.405 1.285 2.165 2 1.835 0 1.76 1217.700 45 1394.5
80 2.995 2.93 2.865 0.3 0.195 0.09 1.21 0 1218.910 34 1428.5
81 3.04 2.93 2.82 0.68 0.575 0.47 2.355 0 1221.265 28 1456.5
82 3.655 3.62 3.585 0.215 0.185 0.155 2.745 0 1224.010 12 1468.5
83 3.625 3.585 3.545 0.15 0.125 0.1 3.495 0 1227.505 24 1492.5
84 2 1.865 1.73 1.165 1.085 1.005 2.5 0 1230.005 45 1537.5
85 2.82 2.685 2.55 0.39 0.3 0.21 1.565 0 1231.570 53 1590.5
86 0.495 0.435 0.375 0.97 0.84 0.71 1.845 0 1233.415 29 1619.5
87 0.46 0.385 0.31 3.55 3.465 3.38 0 3.03 1230.385 23 1642.5
88 0.36 0.34 0.32 3.85 3.81 3.77 0 3.425 1226.960 10 1652.5
89 0.34 0.32 0.3 2.73 2.7 2.67 0 2.36 1224.600 19 1671.5
90 0.66 0.625 0.59 3.775 3.7 3.625 0 3.38 1221.220 17 1688.5
91 3.39 3.34 3.29 0 2.715 1218.505 1688.5
TOT 268.72 50.215 236.995 18.49 1689
WL 4.155 4.105 4.055 19.255 1217.735 218.7 Gross
ARITHMETIC CHECK
BM
ΣB.S.-ΣF.S 218.51 ΣRISE -ΣFALL 218.505 218.505
22
8.2 HEIGHT DIFFERENCE FROM DAM SITE TO POWERHOUSE
WL BM 0.77
SN BS FS RISE FALL RL HD CD
T M B T M B 999.23
1 3.39 3.34 3.29 1000 14 14
2 2.89 2.81 2.73 0.585 0.565 0.545 2.775 0 1002.775 19 33
3 3.25 3.2 3.15 0.19 0.175 0.16 2.635 0 1005.41 14 47
4 3.805 3.765 3.725 0.2 0.18 0.16 3.02 0 1008.43 23 70
5 0.375 0.245 0.115 0.28 0.205 0.13 3.56 0 1011.99 32 102
6 2.59 2.525 2.46 0.485 0.455 0.425 0 0.21 1011.78 36 138
7 0.9 0.785 0.67 2.87 2.755 2.64 0 0.23 1011.55 49 187
8 1.31 1.22 1.13 2.97 2.84 2.71 0 2.055 1009.495 39 226
9 0.475 0.45 0.425 3.755 3.65 3.545 0 2.43 1007.065 13 239
10 0.24 0.22 0.2 3.755 3.715 3.675 0 3.265 1003.8 24 263
11 0.95 0.87 0.79 3.34 3.24 3.14 0 3.02 1000.78 28 291
12 0.35 0.3 0.25 2.38 2.32 2.26 0 1.45 999.33 33 324
13 1.44 1.36 1.28 2.675 2.56 2.445 0 2.26 997.07 40 364
14 2.9 2.775 2.65 1.34 1.22 1.1 0.14 0 997.21 47 411
15 0.55 0.53 0.51 3.98 3.87 3.76 0 1.095 996.115 8.5 419.5
16 0.56 0.545 0.53 3.745 3.725 3.7 0 3.195 992.92 19 438.5
17 0.845 0.805 0.765 2.945 2.865 2.785 0 2.32 990.6 21 459.5
18 0.95 0.93 0.91 1.13 1.115 1 0 0.31 990.29 14 473.5
19 0.4 0.205 0.17 2.84 2.79 2.74 0 1.86 988.43 30 503.5
20 0.895 0.875 0.855 3.665 3.63 3.595 0 3.425 985.005 15 518.5
21 0.085 0.055 0.025 3.76 3.705 3.65 0 2.83 982.175 15 533.5
22 0.455 0.435 0.415 3.54 3.435 3.45 0 3.38 978.795 13 546.5
23 0.43 0.41 0.39 3.87 3.825 3.78 0 3.39 975.405 9.001 555.5
24 0.3 0.28 0.26 3.575 3.55 3.525 0 3.14 972.265 12 567.5
25 0.26 0.245 0.23 3.765 3.75 3.685 0 3.47 968.795 10 577.5
26 0.49 0.47 0.45 3.56 3.525 3.49 0 3.28 965.515 11 588.5
27 0.205 0.18 0.155 3.795 3.76 3.725 0 3.29 962.225 12 600.5
28 0.31 0.29 0.27 2.805 2.77 2.735 0 2.59 959.635 11 611.5
29 1.04 1 0.96 3.54 3.505 3.47 0 3.215 956.42 18 629.5
30 0.44 0.425 0.41 3.31 3.26 3.21 0 2.26 954.16 11 640.5
31 0.09 0.065 0.04 3.51 3.47 3.43 0 3.045 951.115 12 652.5
32 0.5 0.485 0.47 3.955 3.92 3.885 0 3.855 947.26 10 662.5
33 0.135 0.115 0.095 3.655 3.62 3.585 0 3.135 944.125 9 671.5
34 0.22 0.2 0.18 3.73 3.705 3.68 0 3.59 940.535 10 681.5
35 0.39 0.37 0.35 3.41 3.38 3.35 0 3.18 937.355 9.001 690.5
36 0.17 0.15 0.13 3.14 3.115 3.09 0 2.745 934.61 11 701.5
37 0.31 0.29 0.27 3.82 3.785 3.75 0 3.635 930.975 9.001 710.5
23
38 0.365 0.345 0.325 3.62 3.595 3.57 0 3.305 927.67 12 722.5
39 0.36 0.345 0.33 3.5 3.46 3.42 0 3.115 924.555 12 734.5
40 0.64 0.625 0.61 3.43 3.385 3.34 0 3.04 921.515 11 745.5
41 0.24 0.23 0.22 3.72 3.68 3.64 0 3.055 918.46 9.001 754.5
42 0.75 0.735 0.72 3.93 3.895 3.86 0 3.665 914.795 7.001 761.5
43 0.54 0.525 0.51 3.5 3.48 3.46 0 2.745 912.05 11 772.5
44 0.52 0.485 0.45 3.75 3.71 3.67 0 3.185 908.865 17 789.5
45 0.35 0.305 0.26 2.49 2.44 2.39 0 1.955 906.91 15 804.5
46 0.405 0.395 0.385 3.83 3.8 3.77 0 3.495 903.415 9.001 813.5
47 0.52 0.51 0.5 3.66 3.625 3.59 0 3.23 900.185 10 823.5
48 0.66 0.65 0.64 3.65 3.61 3.57 0 3.1 897.085 9 832.5
49 0.6 0.575 0.55 3.435 3.4 3.365 0 2.75 894.335 22 854.5
50 0.48 0.455 0.43 3.515 3.43 3.345 0 2.855 891.48 14 868.5
51 0.57 0.545 0.52 3.605 3.56 3.515 0 3.105 888.375 14 882.5
52 0.78 0.745 0.71 3.55 3.505 3.46 0 2.96 885.415 16 898.5
53 0.755 0.735 0.715 3.64 3.595 3.55 0 2.85 882.565 12 910.5
54 0.45 0.43 0.41 3.67 3.63 3.59 0 2.895 879.67 12 922.5
55 0.48 0.44 0.44 3.95 3.91 3.87 0 3.48 876.19 17 939.5
56 1.195 1.105 1.015 3.64 3.575 3.51 0 3.135 873.055 32 971.5
57 0.65 0.6 0.55 2.885 2.815 2.745 0 1.71 871.345 24 995.5
58 0.36 0.325 0.29 3.09 3.02 2.95 0 2.42 868.925 21 1017
59 0.125 0.105 0.085 3.83 3.76 3.69 0 3.435 865.49 14 1031
60 0.765 0.745 0.725 3.795 3.745 3.695 0 3.64 861.85 21.5 1052
61 0.565 0.55 0.535 3.7 3.615 3.525 0 2.87 858.98 8.001 1060
62 0.585 0.555 0.525 2.785 2.76 2.735 0 2.21 856.77 22 1082
63 0.565 0.535 0.505 3.96 3.88 3.8 0 3.325 853.445 15 1097
64 0.7 0.68 0.66 2.945 2.9 2.855 0 2.365 851.08 18 1115
65 0.955 0.93 0.905 3.42 3.35 3.28 0 2.67 848.41 17 1132
66 0.91 0.87 0.83 3.67 3.61 3.55 0 2.68 845.73 32 1164
67 0.82 0.78 0.74 2.76 2.64 2.52 0 1.77 843.96 22 1186
68 0.555 0.51 0.465 3.83 3.76 3.69 0 2.98 840.98 23 1209
69 0.21 0.165 0.12 0.905 0.835 0.765 0 0.325 840.655 26 1235
70 0.56 0.535 0.51 3.775 3.695 3.605 0 3.53 837.125 18 1253
71 0.48 0.46 0.44 3.9 3.835 3.77 0 3.3 833.825 12 1265
72 0.325 0.295 0.265 3.24 3.2 3.16 0 2.74 831.085 14 1279
73 0.53 0.51 0.49 3.465 3.425 3.385 0 3.13 827.955 13 1292
74 0.525 0.505 0.485 3.48 3.435 3.39 0 2.925 825.03 15 1307
75 0.36 0.34 0.32 3.72 3.665 3.61 0 3.16 821.87 13 1320
76 0.56 0.54 0.52 3.99 3.945 3.9 0 3.605 818.265 9 1329
77 0.3 0.28 0.26 2.885 2.86 2.835 0 2.32 815.945 13 1342
78 0.5 0.485 0.47 3.81 3.765 3.72 0 3.485 812.46 13 1355
24
79 0.645 0.625 0.605 3.98 3.93 3.88 0 3.445 809.015 12 1367
80 0.57 0.54 0.51 3.37 3.33 3.29 0 2.705 806.31 29 1396
81 0.85 0.735 0.62 1.35 1.235 1.12 0 0.695 805.615 39 1435
82 0.62 0.6 0.58 3.45 3.37 3.29 0 2.635 802.98 12 1447
83 0.4 0.385 0.37 3.76 3.72 3.68 0 3.12 799.86 12 1459
84 0.53 0.52 0.51 3.855 3.81 3.765 0 3.425 796.435 8 1467
85 0.42 0.4 0.38 3.8 3.77 3.74 0 3.25 793.185 12 1479
86 0.735 0.73 0.725 3.795 3.755 3.715 0 3.355 789.83 2.001 1481
87 0.4 0.39 0.38 3.665 3.625 3.655 0 2.895 786.935 17 1498
88 0.285 0.255 0.225 3.655 3.58 3.505 0 3.19 783.745 34 1532
89 1.21 1.1 0.99 3.3 3.16 3.02 0 2.905 780.84 42 1574
90 1.69 1.405 1.12 1.26 1.16 1.06 0 0.06 780.78 76 1650
91 2.53 2.42 2.316 1.175 1.08 0.985 0.325 0 781.105 41.4 1691
92 1.25 1.15 1.05 1.27 0 782.375
TOTAL 64.805 282.43 13.725 231.35 1691
WL 2.26 2.16 2.06 0.26
12.715 781.49 217.7
ARITHMETIC CHECK
ΣB.S.-ΣF.S 217.625 ΣRISE -ΣFALL 217.625
25
8.3 CORRECTION BY BOWDITCH’S METHOD
RISE(m) FALL(m) RL(m) correction
adjusted
RL distance(m) C.D.
1000 0 1000.000 0 0
0 1.085 998.915 0.000355 998.915 30 30
0 0.735 998.18 0.001408 998.179 89 119
0.29 0 998.47 0.001775 998.468 31 150
0.505 0 998.975 0.002071 998.973 25 175
3.065 0 1002.04 0.00232 1002.038 21 196
2.64 0 1004.68 0.002426 1004.678 9 205
2.41 0 1007.09 0.002521 1007.087 8 213
2.89 0 1009.98 0.002627 1009.977 9 222
3.68 0 1013.66 0.002757 1013.657 11 233
3.085 0 1016.745 0.002876 1016.742 10 243
3.23 0 1019.975 0.003006 1019.972 11 254
1.915 0 1021.89 0.003704 1021.886 59 313
2.57 0 1024.46 0.00387 1024.456 14 327
2.99 0 1027.45 0.004 1027.446 11 338
3.235 0 1030.685 0.004142 1030.681 12 350
3.37 0 1034.055 0.004284 1034.051 12 362
3.355 0 1037.41 0.004414 1037.406 11 373
3.065 0 1040.475 0.00458 1040.470 14 387
3.08 0 1043.555 0.004746 1043.550 14 401
2.955 0 1046.51 0.004911 1046.505 14 415
2.895 0 1049.405 0.005077 1049.400 14 429
2.915 0 1052.32 0.005255 1052.315 15 444
2.9 0 1055.22 0.005491 1055.215 20 464
3.46 0 1058.68 0.005752 1058.674 22 486
2.34 0 1061.02 0.005953 1061.014 17 503
3.17 0 1064.19 0.006237 1064.184 24 527
2.66 0 1066.85 0.006675 1066.843 37 564
3.715 0 1070.565 0.006947 1070.558 23 587
2.76 0 1073.325 0.007207 1073.318 22 609
2.21 0 1075.535 0.007408 1075.528 17 626
2.57 0 1078.105 0.007515 1078.097 9 635
2.275 0 1080.38 0.007704 1080.372 16 651
2.49 0 1082.87 0.007917 1082.862 18 669
3.21 0 1086.08 0.008024 1086.072 9 678
3.53 0 1089.61 0.008343 1089.602 27 705
2.87 0 1092.48 0.008651 1092.471 26 731
1.455 0 1093.935 0.008982 1093.926 28 759
26
2.51 0 1096.445 0.00916 1096.436 15 774
2.575 0 1099.02 0.009278 1099.011 10 784
2.69 0 1101.71 0.00942 1101.701 12 796
2.87 0 1104.58 0.009562 1104.570 12 808
3.01 0 1107.59 0.009716 1107.580 13 821
3.58 0 1111.17 0.009894 1111.160 15 836
2.08 0 1113.25 0.01013 1113.240 20 856
3.09 0 1116.34 0.010296 1116.330 14 870
3.13 0 1119.47 0.010959 1119.459 56 926
3.36 0 1122.83 0.011065 1122.819 9 935
3.245 0 1126.075 0.011207 1126.064 12 947
1.93 0 1128.005 0.011338 1127.994 11 958
2.445 0 1130.45 0.01148 1130.439 12 970
2.72 0 1133.17 0.011574 1133.158 8 978
2.7 0 1135.87 0.011639 1135.858 5.5 983.5
3.415 0 1139.285 0.011817 1139.273 15 998.5
3.82 0 1143.105 0.011983 1143.093 14 1012.5
3.285 0 1146.39 0.012125 1146.378 12 1024.5
3.25 0 1149.64 0.012243 1149.628 10 1034.5
3.51 0 1153.15 0.012361 1153.138 10 1044.5
2.86 0 1156.01 0.01248 1155.998 10 1054.5
3.65 0 1159.66 0.012586 1159.647 9 1063.5
2.52 0 1162.18 0.012657 1162.167 6 1069.5
3.695 0 1165.875 0.012787 1165.862 11 1080.5
3.165 0 1169.04 0.012894 1169.027 9 1089.5
3.375 0 1172.415 0.013036 1172.402 12 1101.5
3.875 0 1176.29 0.013213 1176.277 15 1116.5
3.465 0 1179.755 0.013474 1179.742 22 1138.5
3.61 0 1183.365 0.013592 1183.351 10 1148.5
3.3 0 1186.665 0.01371 1186.651 10 1158.5
3.215 0 1189.88 0.013829 1189.866 10 1168.5
3.7 0 1193.58 0.013959 1193.566 11 1179.5
3.285 0 1196.865 0.014077 1196.851 10 1189.5
3.265 0 1200.13 0.014255 1200.116 15 1204.5
3.49 0 1203.62 0.014397 1203.606 12 1216.5
3.6 0 1207.22 0.014563 1207.205 14 1230.5
3.015 0 1210.235 0.014776 1210.220 18 1248.5
2.74 0 1212.975 0.015071 1212.960 25 1273.5
3.405 0 1216.38 0.015178 1216.365 9 1282.5
3.08 0 1219.46 0.015415 1219.445 20 1302.5
0 1.76 1217.7 0.015971 1217.684 47 1349.5
27
1.21 0 1218.91 0.016503 1218.893 45 1394.5
2.355 0 1221.265 0.016906 1221.248 34 1428.5
2.745 0 1224.01 0.017237 1223.993 28 1456.5
3.495 0 1227.505 0.017379 1227.488 12 1468.5
2.5 0 1230.005 0.017663 1229.987 24 1492.5
1.565 0 1231.57 0.018196 1231.552 45 1537.5
1.845 0 1233.415 0.018823 1233.396 53 1590.5
0 3.03 1230.385 0.019166 1230.366 29 1619.5
0 3.425 1226.96 0.019438 1226.941 23 1642.5
0 2.36 1224.6 0.019557 1224.580 10 1652.5
0 3.38 1221.22 0.019782 1221.200 19 1671.5
0 2.715 1218.505 0.019983 1218.485 17 1688.5
2.775 0 1221.28 0.020148 1221.260 14 1702.5
2.635 0 1223.915 0.020373 1223.895 19 1721.5
3.02 0 1226.935 0.020539 1226.914 14 1735.5
3.56 0 1230.495 0.020811 1230.474 23 1758.5
0 0.21 1230.285 0.02119 1230.264 32 1790.5
0 0.23 1230.055 0.021616 1230.033 36 1826.5
0 2.055 1228 0.022196 1227.978 49 1875.5
0 2.43 1225.57 0.022657 1225.547 39 1914.5
0 3.265 1222.305 0.022811 1222.282 13 1927.5
0 3.02 1219.285 0.023095 1219.262 24 1951.5
0 1.45 1217.835 0.023427 1217.812 28 1979.5
0 2.26 1215.575 0.023817 1215.551 33 2012.5
0.14 0 1215.715 0.024291 1215.691 40 2052.5
0 1.095 1214.62 0.024847 1214.595 47 2099.5
0 3.195 1211.425 0.024947 1211.400 8.5 2108
0 2.32 1209.105 0.025172 1209.080 19 2127
0 0.31 1208.795 0.025421 1208.770 21 2148
0 1.86 1206.935 0.025586 1206.909 14 2162
0 3.425 1203.51 0.025942 1203.484 30 2192
0 2.83 1200.68 0.026119 1200.654 15 2207
0 3.38 1197.3 0.026297 1197.274 15 2222
0 3.39 1193.91 0.02645 1193.884 13 2235
0 3.14 1190.77 0.026557 1190.743 9.001 2244.001
0 3.47 1187.3 0.026699 1187.273 12 2256.001
0 3.28 1184.02 0.026817 1183.993 10 2266.001
0 3.29 1180.73 0.026947 1180.703 11 2277.001
0 2.59 1178.14 0.02709 1178.113 12 2289.001
0 3.215 1174.925 0.02722 1174.898 11 2300.001
0 2.26 1172.665 0.027433 1172.638 18 2318.001
28
0 3.045 1169.62 0.027563 1169.592 11 2329.001
0 3.855 1165.765 0.027705 1165.737 12 2341.001
0 3.135 1162.63 0.027823 1162.602 10 2351.001
0 3.59 1159.04 0.02793 1159.012 9 2360.001
0 3.18 1155.86 0.028048 1155.832 10 2370.001
0 2.745 1153.115 0.028155 1153.087 9.001 2379.002
0 3.635 1149.48 0.028285 1149.452 11 2390.002
0 3.305 1146.175 0.028391 1146.147 9.001 2399.003
0 3.115 1143.06 0.028533 1143.031 12 2411.003
0 3.04 1140.02 0.028675 1139.991 12 2423.003
0 3.055 1136.965 0.028806 1136.936 11 2434.003
0 3.665 1133.3 0.028912 1133.271 9.001 2443.004
0 2.745 1130.555 0.028995 1130.526 7.001 2450.005
0 3.185 1127.37 0.029125 1127.341 11 2461.005
0 1.955 1125.415 0.029326 1125.386 17 2478.005
0 3.495 1121.92 0.029504 1121.890 15 2493.005
0 3.23 1118.69 0.02961 1118.660 9.001 2502.006
0 3.1 1115.59 0.029729 1115.560 10 2512.006
0 2.75 1112.84 0.029835 1112.810 9 2521.006
0 2.855 1109.985 0.030096 1109.955 22 2543.006
0 3.105 1106.88 0.030261 1106.850 14 2557.006
0 2.96 1103.92 0.030427 1103.890 14 2571.006
0 2.85 1101.07 0.030616 1101.039 16 2587.006
0 2.895 1098.175 0.030758 1098.144 12 2599.006
0 3.48 1094.695 0.0309 1094.664 12 2611.006
0 3.135 1091.56 0.031102 1091.529 17 2628.006
0 1.71 1089.85 0.03148 1089.819 32 2660.006
0 2.42 1087.43 0.031764 1087.398 24 2684.006
0 3.435 1083.995 0.032013 1083.963 21 2705.006
0 3.64 1080.355 0.032178 1080.323 14 2719.006
0 2.87 1077.485 0.032433 1077.453 21.5 2740.506
0 2.21 1075.275 0.032528 1075.242 8.001 2748.507
0 3.325 1071.95 0.032788 1071.917 22 2770.507
0 2.365 1069.585 0.032965 1069.552 15 2785.507
0 2.67 1066.915 0.033179 1066.882 18 2803.507
0 2.68 1064.235 0.03338 1064.202 17 2820.507
0 1.77 1062.465 0.033758 1062.431 32 2852.507
0 2.98 1059.485 0.034019 1059.451 22 2874.507
0 0.325 1059.16 0.034291 1059.126 23 2897.507
0 3.53 1055.63 0.034599 1055.595 26 2923.507
0 3.3 1052.33 0.034812 1052.295 18 2941.507
29
0 2.74 1049.59 0.034954 1049.555 12 2953.507
0 3.13 1046.46 0.035119 1046.425 14 2967.507
0 2.925 1043.535 0.035273 1043.500 13 2980.507
0 3.16 1040.375 0.035451 1040.340 15 2995.507
0 3.605 1036.77 0.035605 1036.734 13 3008.507
0 2.32 1034.45 0.035711 1034.414 9 3017.507
0 3.485 1030.965 0.035865 1030.929 13 3030.507
0 3.445 1027.52 0.036019 1027.484 13 3043.507
0 2.705 1024.815 0.036161 1024.779 12 3055.507
0 0.695 1024.12 0.036504 1024.083 29 3084.507
0 2.635 1021.485 0.036966 1021.448 39 3123.507
0 3.12 1018.365 0.037108 1018.328 12 3135.507
0 3.465 1014.9 0.03725 1014.863 12 3147.507
0 3.25 1011.65 0.037344 1011.613 8 3155.507
0 3.555 1008.095 0.037486 1008.058 12 3167.507
0 2.895 1005.2 0.03751 1005.162 2.001 3169.508
0 3.19 1002.01 0.037711 1001.972 17 3186.508
0 3.505 998.505 0.038114 998.467 34 3220.508
0 0.06 998.445 0.038611 998.406 42 3262.508
0.325 0 998.77 0.03951 998.730 76 3338.508
1.27 0 1000.0400 0.04 1000.000 41.4 3379.908
difference 0.0400 M 3379.908
40 Mm k 3.3799
permissable error 45.96 Mm
Therefore, the head was found to be 218.635 meters.
30
9. FIELD MEASUREMENT OF DISCHARGE
9.1 Determination of Cross Section Two Cross sections of the river were taken. Breadth of the river (length perpendicular to the span of river)
and depth at every 1m gap were taken.
Section A-A
Distance(m) RL
depth
(m)
Distance X
Depth
0 100.596 -0.049 0.0965
1 100.501 -0.144 0.164
2 100.461 -0.184 0.2545
3 100.320 -0.325 0.37
4 100.230 -0.415 0.4095
5 100.241 -0.404 0.231
6 100.587 -0.058 0.029
7 100.645 0.000 0.09106
8.256 100.500 -0.145
∑ 1.64556
Figure 6 Cross Section A-A of river
31
Section B-B
Distance(m) RL(m) Depth(m)
Distance X
Depth
0 99.960 0.000 0.041
1 99.878 -0.082 0.127
2 99.788 -0.172 0.182
3 99.768 -0.192 0.212
4 99.728 -0.232 0.356
5 99.480 -0.480 0.3295
6 99.781 -0.179 0.19764
7.22 99.815 -0.145
∑ 1.44514
Figure 7 Cross Section B-B of River
9.2 Determination of Velocity Current meter could not be used to measure velocity of the river since the depth was too less. Therefore,
float method was applied.
Distance(m) Time taken (sec) Velocity(m/s)
Section A-A
2.9 2.59 1.120
2.9 3.81 0.761
2.9 4.5 0.644
AVG 0.842
Section B-B
5 10 0.500
5 6.29 0.795
5 6.6 0.758
AVG 0.684
32
9.3 Discharge Discharge = Cross Section Area X Velocity
Discharge at Section A-A = 1.64556 X 0.684 = 1.1256 m3/s
Discharge at Section B-B = 1.44514 X 0.842 = 1.2168 m3/s
Average = 1.171 m3/s
9.4 Measurement of discharge from canal Width = 0.6 m
Wetted depth = 0.3 m
Wetted area = 0.18
Distance(m) Time taken (sec) Velocity(m/s)
13 7.84 1.658
13 7.66 1.697
13 8.57 1.517
13 7.83 1.660
13 8.87 1.466
AVG 1.600
33
9.5 Flow Duration Curve
9.5.1 MIP METHOD
Using MIP method to get discharge values for Flow Duration Curve
Month of Field observation of discharge = November = 1.171 m3/s
Converting this into discharge at April 15 = 0.234 m3/s
Months Factor Discharge(m3
/s)
January 2.71 0.635
February 1.88 0.440
March 1.38 0.323
April 1 0.234
May 1.88 0.440
June 3.13 0.733
July 13.54 3.172
August 25 5.856
September 20.83 4.879
October 10.42 2.441
November 5 1.171
December 3.75 0.878
34
9.5.2 Flow Duration Curve
Rank
Probality of
exceedence % Discharge (m3
/s)
1 8.333 5.856
2 16.667 4.879
3 25.000 3.172
4 33.333 2.441
5 41.667 1.171
6 50.000 0.878
7 58.333 0.733
8 66.667 0.635
9 75.000 0.440
10 83.333 0.440
11 91.667 0.323
12 100.000 0.234
Figure 8 Flow Duration Curve
By interpolation, Q65 =0.654 m3/s
35
9.6 TOTAL DISCHARGE
Total Discharge that can be utilized
= Discharge from river + 2 canals
= 0.654 + 0.216 + 0.216 m3/s
=1.086 m3/s
36
10. FINDING HYDROPOWER POTENTIAL USING OBTAINED FIELD INFORMATION
10.1 Design of penstock for that hydropower potential
Using USBR formula,
Veco=0.125√2gH = 8.187 m/sec
D=√(4Q/πv) = 0.411 m
Using Sarkaria Formula,
Power (P) = γQHη = 1980.6 kW = 2654.96 HP
D = 0.62 P0.35= 0.295 m
H0.65
From JNN Guidelines,
D=√5.2Q3
H
7 = 0.61 m
Pressure inside Penstock (p) = ρg (H+H0) where, Dynamic head (H0)= v2/2g
Therefore, ρg (H+H0) = 22.2051 kg/cm2
t= pD/2σaη + ε (ε: Corrosion allowance 0.2 cm)
= 0.861 cm
As per ASME code:
t= pR/(σaη-0.6 p) + 0.15 = 0.82 cm
tmin= D/ 288 = 0.211 cm
tmin= (D+200)/400 = 0.652 cm
37
10.2 Penstock Alignment
Due to lack of topographic map of the exact location and scale of Sundarijal HPP available to us, we used a
Google Maps service provided by Google Inc. as it readily provides satellite images and elevation contours.
The aim of taking this image is to get an idea of the length of the penstock that can be put so as to check the
hydropower potential of the river. The accuracy of this method can be in doubt however, the scope is to find
the length only so it is preferable.
Figure 9 Penstock Alignment
The alignment is shown by the straight lines enclosed within small square boxes. The total length of the
alignment was found to be 1.41 km.
38
10.3 Calculation of major and minor losses
10.3.1 Calculation of friction factor Relative roughness = 0.00004167
Reynold’s number (Re) = ρvD/μ = 2.263x106
From Moody Chart, friction factor (f) = 0.0116
Figure 10 Moody Diagram
39
10.3.1 Calculation of head loss
• Major loss (Darcy Wiesbach Formula)
fLv2/2gD
= 19.149 m
• Minor loss
(v2/2g) (kentrance+kbend+kexit)
= 1.268 m
Total loss (HL) = 19.149+1.268 = 20.417 m
10.4 REMARKS
Taking losses into account, Power = γQη(H-HL) = 1795.65 kW ~1.8 MW
(taking overall efficiency of turbine and generator 85%)
This power is calculated using Q65
Whereas Q40 is used in the original design and it produced 1.24 MW
REMARKS: The HPP still has more potential.
40
11 CALCULATION OF FIRM POWER AND SECONDARY POWER Table 1 Calculation of power and
energy Calculate the wet firm and secondary power and energy
Calculate the dry firm and secondary power and energy
Design QD at
Wet period Dry period
Q65%
M No. of days
Flow m3/s
m3/s Power [kW] Energy [kWh]
Firm Sec Firm Sec Firm Sec Firm Sec
Pow. [kW] Pow. [kW] Ener [kWh]. Ener. [kWh]
Pow. [kW]
Pow. [kW]
Ener. [kWh]
Ener. [kWh]
1 2 3 4 5 6 7 8 9 10 11 12 13
J 31 0.63 1.04 1720.76 1280243.12 1060.17
660.58 788769.01
491474.11
F 28 0.44 0.85 1400.12 940882.51 1060.17
339.95 712436.52
228445.98
M 31 0.32 0.73 1206.97 897985.46 1060.17
146.80 788769.01
109216.45
A 30 0.23 0.64 1060.17 763324.82 1060.17 0.00 763324.85 0.00
M 31 0.44 0.85 1400.12 1041691.35 1060.17 339.95 788769.01 252922.34
J 30 0.65 1.06 1752.45 1261764.39 1060.17 692.28 763324.85 498439.55
J 31 0.65 1.06 1752.45 1303823.21 1060.17 692.28 788769.01 515054.20
A 31 0.65 1.06 1752.45 1303823.21 1060.17 692.28 788769.01 515054.20
S 30 0.65 1.06 1752.45 1261764.39 1060.17 692.28 763324.85 498439.55
O 31 0.65 1.06 1752.45 1303823.21 1060.17 692.28 788769.01 515054.20
N 30 0.65 1.06 1752.45 1261764.39 1060.17 692.28 763324.85 498439.55
D 31 0.65 1.06 1752.45 1303823.21 1060.17
692.28 515054.20
788769.01
J 365 13924713.25
8481.39 4493.61 6208375.43 3293403.56
4240.69
1839.61 2805028.74
1617905.55
41
REMARKS:
1 Installed Capacity Pinst, kW 1933.36
2 Firm Capacity, Pfirm, kW 1169.62
3 Total Wet Energy [kWh] 9501778.99
4 Total Dry Energy [kWh] 4422934.29
5 Annual Energy Consumed [kWh] 13924713.28
6 Total Annual Energy Could be Produced [kWh] 16936224.31
7 Annual Plant Factor 0.8222
8 Annual Load Factor 0.8222
9 Annual Utilization Factor 1
10 Total cost of Hydropower 290003841
11 Total annual benefit from hydropower 82761187.2
12 Total annual cost of hydropower installation and operat. for 30 years 30740407.14
13 Benefit -cost ratio 2.6923
14 Your candid conclusion Economically Feasible
(Taking the cost of hydropower into annuity taking interest is equal to 10)
42
12. CALCULATION OF FLOW MASS CURVE
S.N. Months Factor Discharge(m3/s) Days Volume (m3/day)
Cumulative volume (m3-
day)
1 January 2.71 0.635 31 19.678 19.678
2 February 1.88 0.440 28 12.330 32.008
3 March 1.38 0.323 31 10.021 42.029
4 April 1 0.234 30 7.027 49.056
5 May 1.88 0.440 31 13.651 62.708
6 June 3.13 0.733 30 21.995 84.702
7 July 13.54 3.172 31 98.319 183.021
8 August 25 5.856 31 181.534 364.555
9 September 20.83 4.879 30 146.375 510.930
10 October 10.42 2.441 31 75.663 586.593
11 November 5 1.171 30 35.136 621.728
12 December 3.75 0.878 31 27.230 648.959
Figure 11 Flow Mass Curve
From the curve plotted, it is assumed that the reservoir is full at the beginning of a dry period i.e. when
the inflow rate is less than the demand rate, the maximum amount of water drawn from the storage is the
cumulative difference between supply and demand volumes from the beginning of the dry season.
Therefore the storage required, S = Maximum of ∑Vd - ∑Vs where, Vd is Demand Volume and Vs is
supply volume.
The estimated capacity for which the reservoir is to be designed is 84 cumec-day
i.e 84 X 24 X 60 X60 = 7.256 million cubic meter per second.
13 .DESIGN OF SUPPORT PIER
13.1 Design Support piers are required along the straight sections of exposed penstock between anchor blocks. The
maximum spacing of support piers to avoid overstressing the pipe is generally 5.
Design considerations:
1. Component of the weight of pipe and enclosed water
2. Frictional force of pipe on support piers
3. Force on the anchor blocks on support piers due to the soil pressure acting on the upstream face
Factors not included in the design:
1. Since there is only one minor bend, the hydrostatic pressure within the bend was neglected.
2. Thermal expansion and contraction effects.
43
3. Pipe diameter reduction
To find total force acting on support piers:
Span of penstock supported by support pier = 5m
Internal Diameter of penstock = 0.6m
Thickness of penstock = 9.00mm
Thickness of saddle plate = 18.00mm
Density of steel taken = 8050 kg/m3
Density of water = 1000 kg/m3
Span of steel saddle plate resting on pier = 1.12m + 0.5d + 0.5d = 2.12 m
Weight in kilograms = Density X Volume
Wpenstock= 8050 X 5 X (2 π r X t) =683.1 kg
Wsaddle= 8050 X (1.25 X π r X 2t) = 235.17 kg
Wwater enclosed = 5 X π r2 X 1000 = 1414.286 kg
Total Force due to weight of penstock, saddle and water enclosed, F1=2332.56kg
Friction co-efficient, f = 0.57
Frictional force, F2=fXF1=1329.557706
Unit weight of soil = 16 kN/m3
Friction angle, ø = 22°
Thrust acting on the face of pier, F4= 153.34 kg
Weight of pier, F3= 19224.99 kg
This weight is calculated after determining the dimension of the pier.
44
Figure 12 Cross Section of Penstock
45
Figure 13 Support pier elevation with saddle and penstock
46
Figure 14 Cross section of penstock resting on support pier
47
After several iteration, the following dimension yield safe remarks on all three checks.
L = 2.2m, B = 2.0 m, H = 2m,
Sum of moments about bottom right end of the pier, ∑M = 23595.33 kg m
Sum of vertical forces,∑V =21299.30 kg
Sum of horizontal forces, ∑H = 1150.90 kg
13.2 Stability Analysis Checking of conditions of stability is required and an iterative process was done to determine the safe
dimension of support pier.
SAFETY ON OVERTURNING
The forces acting on the structure should not overturn the block. For structures that have rectangular
bases, this condition is met if the resultant acts within the middle third of the base.
Distance at which the resultant acts, d= ∑M / ∑V = 1.11 m
where,
∑M = sum of moments acting about the chosen point of the block
Eccentricity, e = │0.5 L - d│ < allowable eccentricity = L/6 i.e 0.0078 < 0.3667
SAFE ON BEARING
The load transmitted to the foundation must be within the safe bearing capacity limit of the foundation
material. If the transmitted load exceeds the bearing capacity limit of the foundation, the structure will
sink. The bearing pressure at the base is checked using the following equations:
Pbase= ∑V/Abase(1+ 6e/L) = 4943.7 kg/m2
where Pbase= maximum pressure transmitted to the foundation
V = the sum of vertical forces acting on the block
L = length of the base
A = base area of the block
The allowable bearing pressure of soft clays and silts = 5000 kg/m2> Pbase
SAFE AGAINST SLIDING
The structure should not slide over its foundation which is checked as:
µ ∑V / ∑H ≥ 1.5
7.48 ≥ 1.5
µ = Friction co-efficient between the block and the foundation = tanø
The dimension taken was taken so that they satisfy safety on all three cases which can be built to replace
the degraded ones at the site.
48
13.3 Cost Estimation
Total Volume = 3.125 m3
This is the volume of PCC used to construct the support pier.
Analysis of Rates of PCC (1:2:4) in foundation and super-structure
Particulars Quantity or Nos. Rate Cost
Excavation 2.42 m3 NRs. 180 per cu.m NRs. 435.60
Materials
Cement
Sand
Aggregate
13.5 bags
9.75 cu.ft
17.7 cu.ft
NRs. 800 per bag
NRs. 90 per cu.ft
NRs. 81 per cu.ft
NRs. 10,800.00
NRs. 900.00
NRs. 1,430.00
Manpower
Skilled
Unskilled
1 for 2 days
4 for 2 days
NRs. 530 per Manday
NRs. 320 per Manday
NRs.1,060.00
NRs.2,560.00
Total NRs.17,185.60
Add 1.5% for water charges = NRs. 257.78
Add 10% Contractor’s profit = NRs. 1,718.56
Total = NRs. 19,161.34
Three such piers need to be constructed, hence Grand Total = NRs. 57,484.02
49
14. INSPECTION WORKS
The power house has a 5 ton lifting crane working properly and staffs are positioned which take
required data at regular intervals.
The turbines which were kept for repair had large eroded parts. So, a valuable decision will be
cleaning the reservoir so that the silts can settle down and prevented from getting into the penstock.
There are also possibilities of bringing more water from rivers to the reservoir; that is mainly from
Nagmati as very less water is diverted. Using this extra amount of collected water new set of
equipments can be set up in the powerhouse.
The canal of Shayalmati has also to be rennovated as at many places the walls have been collapsed.
There are some leakages in penstock but these can be sealed off.
The anchor blocks along the penstock have deteriorated and are at the verge of collapse (See pictoral
highlights fig.2 and fig.3) which need to be repaired.
Huge amounts of sediments were found at the reservoir. As a temporary solution, some lumps of silt
were manually taken out to the bank of the reservoir. Necessary flushing mechanism need to be put
into operation.
The rehabilitation of this power station is underway under the joint assistance from ADB, GON and
NEA. NEA has received loan from ADB towards the cost of Power Efficiency Improvement as part of
Electricity Transmission Expansion and Supply Improvement Project. NEA intends to apply a portion
of the proceeds of this loan for Rehabilitation of Sundarijal HPP. The proposed rehabilitation works
largely consists of electro-mechanical rehabilitation and recruitment of international individual
consultant in intermittent assignment for design and implementation support for Part C: Rehabilitation
of small HPP.
Mechanical Works:
a. Repair and maintenance of runner buckets in both units.
b. Penstock repair and maintenance works.
c. Repair oil cooler of turbines
Electrical works:
a. Rewinding of excitor of turbines
b. Replacement of 3.3 kV XPLE cable from generator to step-up transformer and 11 kV cable
from switchyard to pole with cable termination kit.
Civil Maintenance Works:
a. Repair of canal from Nagmati to Bagmati Forebay.
b. Cleaning of Balancing Reservoir.
c. Construction of four numbers of penstock support pillars near Bhatte Danda.
d. Construction of single storey new staff quarter.
50
15. PUBLIC CONSULTATION The dam site of Sundarijal HPP lies at Shivapuri National park which makes it a very busy domestic and
tourist site especially at weekends. The natural beauty, picnic spots, rivers and pond to swim makes it a
very important place to be with family and friends. This had led to an increase the value of this place in
commercial terms as well. Sundarijal HHP adds an intake, reservoir and dam sites which makes the place
beautiful in aesthetic sense.
Local people are conscious about the maintenance of the civil structures, i.e. penstock and support piers
mainly. They face the normal loadshedding schedule although 1 hour less each day.
The people in the locality whose houses are nearby along the penstock length have stated their
dissatisfaction regarding the regular maintenance. The public showed interest in the upgradation as well,
i.e. upgradation from 640kW to 1.2 MW.
In the past, tenders for maintenance and operation were given to the local by NEA which accumulated a
budget enough to employ certain manpower of the society. |However, currently, the tender has been given
to others besides the local; this change in procurement of services had upset the local. Their claim is that
the lack of rehabilitation detected at the site was due to this conflict.
51
16. PROJECT SCHEDULE
52
17. OUTCOMES
The outcomes of this project are as follows:
i. Head of the hydropower was determined by field work which was then compared with the recent
measurement done by NEA and was found to be nearly equal.
ii. Degraded civil components were detected.
iii. Data collection and calculation of various hydropower parameters can be utilized in development
works
iv. Design and suggestions made in this report can be a motivation for rehabilitation of this HPP in future.
18. LIMITATIONS OF THE PROJECT The whole span of the penstock alignment could not be inspected since some part were
inaccessible.
Inspection of the total quantity of silt deposited in the reservoir was not determined.
19. CONCLUSION AND RECOMMENDATIONS This mini-project was successful to achieve its objectives. Regarding RUM, several degradations have
been put into highlights in this report and suitable suggestions have been provided. With the regular RUM
works done by NEA, Sundarijal HPP has more potential to develop and increase its power generation.
This report can be very useful as a reference whenever head, discharge, flow duration curve, flow mass
curve, check for power potential, design of support piers, etc. will be of need to be referred to in the
future.
53
20. REFERENCES Bathtub curve. (2014, March 3). Retrieved from Wikipedia, the free encyclopedia:
http://en.wikipedia.org/wiki/Bathtub_curve
Authority, N. E. (n.d.). TERMS OF REFERENCE. Nepal: Electricity Transmission Expansion and Supply
Improvement Project. Kathmandu University, Nepal: Nepal Electricity Authority.
Dutts, B. N. (2013). Estimating and Costing in Civil Engineering. New Delhi: UBS Publishers' Distributors Pvt.
Ltd.
Goldberg, J., & Lier, O. E. (n.d.). REHABILITATION OF HYDROPOWER - An introduction to economic and
technical issues. worldbank.org.
Subramanya, K. (n.d.). Engineering Hydrology. Tata McGraw Hill.
54
PICTORIAL HIGHLIGHTS
Photo: 3 Dam
Photo: 1 Penstock resting on support pier Photo: 2 Displaced Anchor Block
55
Photo: 4 Reservoir
Photo: 5 River Stretch
56
Photo: 6 Canal Section
Photo: 7 Trash Rack at Canal
57
Photo: 8 Source of Canal
Photo: 9 Team performing Fly Levelling