mangla dam
TRANSCRIPT
College of Earth and Environmental
Sciences, University of the Punjab,
Lahore.
Study tour report of three days
Submitted by:Sadam hussain khan
M.Sc. Applied Hydrology 4th semester
Submitted to:Dr. Iftikhar Ahmed
Dr. Zahid karim Khan
Mr. Waqar Ahmed
Miss Zaib-u-nisa
Tour places:Tour to Mangla Dam on Jhelum River, Khanpur Dam on Haro River and Rawal
Dam korang River in Islamabad.
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Table of contents:
1. 1st day---------------------------------------------------------------------------1
1.1. Introduction--------------------------------------------------------- 12. Study tour working schedule---------------------------------------------2
2.1. 1st day 17/04/2015-----------------------------------------------------------22.2. 2nd day 18/04/2015-----------------------------------------------------------22.3. 3rd day 19/04/2015-----------------------------------------------------------2
3. Study tour objectives-------------------------------------------------------34. Methodology------------------------------------------------------------------45. Mangla Dam-------------------------------------------------------------------5
5.1. Introduction------------------------------------------------------------------55.2. Key facts of mangla dam----------------------------------------------------55.3. THE MANGLA DAM PROJECT -----------------------------------------------5 5.3.2. Main spillway----------------------------------------------------------5 5.4. Main elements of Mangla Dam---------------------------------------------55.5. Financial Benefits------------------------------------------------------------55.6. THE MANGLA WATERSHED MANAGEMENT PROJECT--------------------5 5.7. Mangla Rising----------------------------------------------------------------55.8. THE RESSETLEMENT ISSUE---------------------------------------------------5
6. Khanpur Dam-------------------------------------------------------------------66.1 Introduction---------------------------------------------------------------66.2 Salient Features-----------------------------------------------------------66.3 Seepage Problems--------------------------------------------------------66.4 Geology setup------------------------------------------------------------6
7. Ghazi brotha reservior------------------------------------------------- 77.1. Introduction: --------------------------------------------------------------- 77.2. The Project: ---------------------------------------------------------------- 77.3. The Barrage: --------------------------------------------------------------- 77.4. The Power Channel: ------------------------------------------------------- 77.5. Mechanical and Electrical Equipment: ---------------------------------- 77.6. Project Financing: --------------------------------------------------------- 7
8. Rawal Dam----------------------------------------------------------------------88.1 Introduction----------------------------------------------------------------8
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8.2 Salient Features------------------------------------------------------------88.2.1. Spillway: -----------------------------------------------------------------88.2.2. Reservoir: ----------------------------------------------------------------88.2.3. Canals: -------------------------------------------------------------------88.2.4. Drinking water supply: --------------------------------------------------88.2.5. Command area: ----------------------------------------------------------8
9. References------------------------------------------------------------------------9List of Figures:
1.1. Hydrological map of Pakistan---------------------------------------------- 12.1. view of Mangla Reservoir------------------------------------------------ -- 2 5.1. Spillway of the dam ----------------------------------------------------------- 35.2 power house station. ------------------------------------------------------- 46.1. Khanpur Dam---------------------------------------------------------------- 57.1. Ghazi brotha reservoir------------------------------------------------------ 67.2 ghazi brotha chennel ------------------------------------------------------- 7 8.1. Rawal Dam------------------------------------------------------------------- 8
1. 1st day.
1.1 Introduction:
We have started our study tour from our college of earth and environmental
sciences (CEES) department Punjab University (PU) at 16th April morning 8:00am. In front of (CEES)
department every class GR and CR have taken attendance of their class fellows. And then started
journey toward Mirpur district of Azad Kashmir. where there is Mangla Dam. We had one university
bus and one van for the teachers in the tour. So everyone took their bags and baggage’s, and on the
way we also enjoyed a lot till we were reaching to Mangla. We have stopped on the way of qyaam-
u-thaam for refreshment. There we bought some nutrients/food. And then again we started our
journey toward Mangla Dam. So we reached to Mangla Dam at about 1:30pm. And we have waited
there for getting permission from the Mangla Dam staffs about 30 minutes. There we also made
some pictures until they were giving us permission. When they permitted us, all the students and
teachers were going by feet towards hydro power station. And they have banned taking pictures
inside. So I was going with Dr Zahid khan, sir waqar and my class fellow on the way to hydropower
station that Dr Zahid was giving us some information about external structure of the Dam. And we
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were noting that information in notebook. So when we inter to the main station they have provided
us two lecturer`s for giving us lectures about Mangla Dam. So I was surprised to see the structure of
the instruction of the machinery in the hydro power station. And there was some painting also
inside that station. That was a really big station. I was noting even the name of machinery. Most of
the machinery was made of Japan, as Hitent LTD, JOMBO, MONOBAloa, voth hydro water turbine.
So inside story of the Dam and about the hydro power station will be discussed later. After that we
were getting tired and gone to the top of the Dam and took dinner there. We have eaten chicken
beryani with cocks. And upper the prayer. And then we have started our journey toward Islamabad.
There is youth hostel, so there we stayed for night. And there were some other students also
present. They were also on tour from swat city. We have took the lunch and then upper the prayer
and slept. So teachers were on top of the floor, girls were on 2nd floor and boys were on the 1st floor
of the ground. There were PHD, M.PHILE and M.SC students with us on study tour.
Figure of the map.(1.1
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2. Study tour working schedule:
2.1. 1st day 17/04/2015
The 1 st day traveling from Lahore to Mangla dam, a Lecture by Dr.
Zahid Karim Khan on soil and river bed of Jhelum River and Mangla dam and a lecture By
Dr.Iftikhar Ahmed on Mangla dam. Visit to Mangla reservoir and a lecture delivered by
Dr.Iftikhar and one other lecturer at Mangla dam and. And then at Night in Youth Hostel
Islamabad. There we stayed.
view of Mangla Reservoir (2.1)
2.2. 2nd day 18/04/2015
A lecture was delivered by an official office MR. Asim Israr and
Dr.Iftikhar about Khanpur dam on the Embankment of the dam. The dam was visited
thoroughly, And a visit was as well paid to the Margla hills in Islamabad.
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And our 2nd visit was to Ghazi-Barotha Hydropower station at about 10 km (6.2 mi) west of
Attock in Punjab, Pakistan. Lecture was delivered by mahir-ur-hman yousafzai official
professor of ghazi brotha reservoir.
2.3. 3rd day 19/04/2015
The last day of the tour. A lecture was delivered by Dr. zahid karim
khan and Dr. Iftikhar Ahmed on rawal dam, that was situated in Islamabad and a visit to
Khewra mines as well was the part of the tour, And then travelled back to Lahore.
3. Study tour objectives:The main objective of this tour was to have an understanding of nature of dams,
their working and processes occurring within them. In other words it was aimed at
enhancing our knowledge about water Sciences in an applied way. The other objectives
included obtaining geological, geographical and general knowledge. Entertainment was
as well a part of the tour.
4. Methodology: Lectures were delivered by the teachers in field and students were evoked
to discussions. And asked questions about related subject. Officials were consulted and asked
to share their applied knowledge. Close observations to the things were made. Class lectures
were as well the part of study tour.
5. MANGLA DAM:5.1. Introduction.
The Mangla Dam is a multipurpose Dam, which is located on the Jhelum
River in the Mirpur district of Azad Kashmir. As such the primary objective of the
project was to create water storage to meet the irrigation water demand of
irrigated area commanded by these rivers. It is 9th largest Dam in the world.
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Mangla Dam was constructed at a cost of Rs. 15.587 billion (US$1.473 billion)
with the funding being provided by the World Bank and Asian development bank.
The Dam was constructed between 1961 to 1967 on the Jhelum River, about 67
miles (108 km) south-east of the capital of Pakistan (ISLAMABAD). The
components of the dam include a main embankment, a reservoir, intake
embankment, main spillway, emergency spillway, 5 tunnels and a power station.
About 280 villages and the town of Mirpur submerged in the Mangle dam.
5.2. Key FACTS of Mangla Dam:
Dam Type: Earth fill
Height: 380 ft. (above riverbed)
Length: 10,300 feet`
Lake Area: 97.7 sq. miles
Catchment Area: 12,870 Sq miles
Gross Storage Capacity: 5.88 MAF
Live Storage Capacity: 5.34 MAF
Main Spillway Capacity: 1.01 million cusecs
Year of Completion: 1967
Hydropower Generation: 1,000 MW from 10 units of 100 MW each
No. of people to be displaced
by raising of dam: 40,000
5.3. THE MANGLA DAM PROJECT:
Mangla Dam is the 9th largest dam in the world. It was constructed in 1967 Across the
River Jhelum, about 67 miles southeast of the federal capital, Islamabad. The main structures
of the dam include 4 embankment dams, 2 spillways, 5 power-cum-irrigation tunnels and a
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power station. The main dam is 10,300 feet long and 454 feet high (above core trench) with a
reservoir of 97.7 square miles. Since its first impounding in 1967, Sedimentation to the extent
of 1.13 MAF has occurred, and the present gross storage capacity has reduced to 4.75 MAF
from the actual design of 5.88 MAF. The live capacity has reduced to 4.58 MAF from 5.34
MAF. This implies a reduction of 19.22 % in the capacity of the dam. The project was designed
primarily to increase the amount of water that could be used for irrigation from the flow of
the River Jhelum and its tributaries. Its secondary function was to generate electrical power
from the irrigation releases at the artificial head of the reservoir. The project was not
designed as a flood controls structure, although some benefit in this respect also arises from
its use for irrigation and water supply.
5.3.2. Main spillway:A spillway is a section of a dam designed to pass water from the upstream side of the
dam to the downstream side. Many spillways have floodgates designed to control the flow
through the spillway. Types of spillway include a service spillway or primary spillway passes
normal flow. And an auxiliary spillway releases flow in excess of the capacity of the service
spillway.
Figure of Spillway of the dam (5.1)
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5.4. MAIN ELEMENTS OF MANGLA DAM:
The Mangla Dam components include a reservoir, main embankment, intake
embankment, main spillway, emergency spillway, intake structures, 5 tunnels and a power
station. Besides the main dam, a dyke called Sukian – 17,000 feet in length and a small dam
called Jari Dam to block the Jari Nala – about 11 miles beyond the new Mirpur town had to be
constructed. There was a total of 120 x 106 yds3 of excavation for the reservoir whereas the
total fill amounted to 142 x 106 yds3 and concrete to 1.96 x 106 yds3 respectively. The main
embankment is earth fill with clay as the core material. Gravel and A-type sandstone are
applied on the shoulders. The maximum height of embankment above the core trench is 454
feet and the length is 8,400 feet. The intake embankment is earth fill type with B-type
sandstone as the core material. Gravel is applied on the shoulders. The maximum height of
intake embankment above the core trench is 262 feet and the length is 1,900 feet. Sukian
Dam is earth fill with B-type sandstone as the core material. A-type sandstone is applied on
the shoulders. The maximum height of the intake embankment above the core trench is 144
feet and the length is 16,900 feet. J Jari Dam is also an earth fill type with silt as the core
material. Gravel is applied on the shoulders of the dam. The maximum height of Jari dam
above the core trench is 274 feet and the length is 6,800 feet. The main spillway is a
submerged orifice type with 9 radial gates, 36 x 40 feet each; it has a maximum capacity of
1.1 million cusecs. The emergency spillway is weir type with an erodible bund and a
maximum capacity of 0.23 million cusecs. The 5 tunnels are steel and concrete lined and
1,560 feet long in bedrock. The internal diameter ranges between 26-31 feet. The power
station has 10 vertical Francis type turbines, each generating 100 MW of power.
5.5. THE MANGLA POWER STATION:There are total 5 tunnel and 10 turbines of power house has been constructed at point
of intake embankment at the ground surface elevation of 866ft, SPD. Each tunnel is designed
to feed two generating units. Power house discharges water into new bong canal. And there
were two types of release (1) power generation release of water (2) without power
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generation release of water. In power station different functions were performing by
different means for example the gate of spillways and tunnels are controlled by means of
hydraulic pressure system. So that water flows in the tunnels and applied a force on the
blades of the turbine. This rotates in the magnetic field. As a result of it magnetic flux changes
which causes to induce the electric city. And there were some painting inside the constructed
station as will about hydro.
Figure of power house station. (5.2)
5.6. FINANCIAL BENEFITS:The Indus River System Authority (IRSA) indented 4.21 MAF of water releases for
irrigation purpose during 1999-2000, against 5.1 MAF during the previous year, worth Rs
3,789 million at a rate of Rs. 900 per acre-feet. In addition, the Mangla Power Station
generated 3,184.77 million kilowatt hours (MKWH) of electricity, worth Rs. 955.43 million at a
rate of Rs. 0.30 per kwh unit.
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5.7.THE MANGLA WATERSHED MANAGEMENT
PROJECT:The primary objective of this project is to prolong the life of the Mangla reservoir
through improved methods of land-use and implementation of watershed management
practices in the catchment area above Mangla dam. The project, besides reducing silt entry
into Mangla reservoir, has also improved the following: ÿ socio-economic conditions of the
people living in the area by improvement of land with consequent increase in agriculture, ÿ
forest and range-land produces, ÿ increase in sub-soil water resources and perennial stream
flows, ÿ minimizing runoff with consequent reduction in flood hazards and ÿ environmental
protection of the area The total catchment area of the River Jhelum above Mangla is 12,870
square miles. 56% of this lies in the Indian-held Kashmir territories and the remaining 44% in
Pakistan and Azad Jammu and Kashmir. Of the total area in Pakistan, only 3,433 square miles
is covered by this project, which includes the critical sediment source areas. The watershed
management practices include reforestation of bare and denuded lands, development of
range-lands, improvement of cultivated fields by land leveling/ improvement of terraces and
structural works such as silt trap storages, spillways, check dams, retaining diversion walls
and gully control Structures.
5.8. THE RAISING OF MANGLA DAM:A joint venture of consultants comprising NESPAK, Barqaab, Binnie and Partners and
Harza has been awarded the contract to undertake the feasibility for raising Mangla Dam by
40 feet. The proposal for rising of Mangla Dam was part of the Final Completion Report
submitted by Binnie and Partners in 1971. This will raise the elevation of the dam from 1,234
feet to 1,274 feet and subsequently increase the conservation level from 1,202 feet to 1,252
feet and the minimum operating level from 5.88 MAF to 9.6 MAF.
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5.9. THE RESSETLEMENT ISSUE:During the construction of the Mangla dam, 65,100 acres of land was
submerged. This led to the resettlement of the residents of old Mirpur town and the
affected people were provided accommodation in the newly designed and developed
town of Mirpur. Most of the people were accommodated however, some grudges
remained after resettlement. An important concern on the raising of Mangla dam is
the resettlement of an estimated 40,000 people living in 7,000 houses. Some of these
may be the same people or their descendants who would force to leave their
hometown for the second time. Rs. 20 billion have been allocated for population
resettlement in the Rs 53 billion project. WAPDA is developing.
6. Khanpur Dam / Lake :
6.1. Introduction:Khanpur dam one of the most beautiful dams is constructed over River
Haro which originates from Abottabad. It is situated near the town of Khanpur
in Khyber Pakhtunkhwa Province around 48 km (25 miles) from the federal
capital Islamabad, on Taxila Haripur Road. Khanpur Lake is a reservoir which
supplies drinking water to Islamabad and Rawalpindi and irrigation water to
many of the agricultural and industrial areas surrounding the cities. The dam
was completed in 1983 after a 15 year construction period believed to have
cost Rs. 1,352 million. The dam was named after the former Khanpur village. A
new Khanpur town is located in downstream of the Dam. It is 167 feet (51 m)
high and stores 110,000 acre feet, 140,000,000 cubic meters of water. Known
for its picturesque beauty, Khanpur Lake (the reservoir of the dam) has become
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a popular tourist destination and a picnic spot. The beautiful and serene
environment is also a sanctuary for migratory birds during winter.
Figure khanpur dam: (6.1)
6.2. Salient feature of khanpur dam:
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6.3. Seepage problems:
Seepage problem is one of the important tasks to be resolved
associated with embankment dams. Often preconstruction arrangements are
made to reduce the seepage through dam’s abutments and valley fill deposits.
The usual treatments include grouting; cut-off wall, clay blanketing and dental
treatments which are adopted to cut down the possible seepage paths. The
amount of seepage and type of treatments are directly related to the nature of
geological formations and associated structural features. For the past twenty
five years of dam operation seepage is still one of the major problem at
Khanpur Dam Project. At maximum conservation level of 1980 feet seepage
quantity is about 50% of the base inflows of the river and its increasing trend is
a threat to the dam safety and water storage. The study of the geological
aspects indicates that the major seepage paths are associated with limestone
formations and through a number of normal faults in Chohae area. Instead of
costly treatment over a large scattered area, management measures are
suggested for conservation of reservoir and utilization of 35% of seepage water
at gravity flow.
6.4. Geological setup:
The geology of Khanpur dam site is predominantly composed of
limestone formation of Margalla Hill limestone Formation of Eocene age (Shah,
1977). Associated Consulting Engineers have classified the formation into
twelve rock units given in Table 1 (ACE, 1984). The river valley at dam site is
filled with thick alluvial deposits. Series of anticline and syncline structures are
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present in the area. The river at dam site flows through eroded anticline where
as right and left abutments are synclines as shown in the typical cross section
along the axis of the main dam (Fig. 2). The strike of all these rock units is day
lighting in the reservoir from where huge amount of water enters through
contact planes and discontinuities which seeps out downstream of the dam. An
uninvestigated source of seepage is from Chohae area where a number of
normal faults are responsible for huge amount of water loss through seepage.
7. Ghazi-Barotha reservoir Hydropower
Project:
7.1. Introduction:The shortage of electrical power at affordable cost has long been identified as
one of the main hurdles to the industrial and economic growth of Pakistan. The
demand for electricity is growing rapidly and requires a considerable increase in the
rate at which new generating capacity is introduced. Presently demand is met through
a mix of thermal and hydroelectric plants. The percentage of thermal power
generation has continued to increase in recent years, with a noticeable impact on unit
cost of generation. WAPDA has continually sought to maximize the country’s capacity
for Hydropower generation and reduce the dependence upon thermal power
generation. Ghazi Barotha Hydropower Project with a generation capacity of 1450
MW and an average energy output of 6600 GWh is a large, renewable and emission
free source of energy towards WAPDA’s Vision 2025 goals.
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Figure of GHAZI BROTHA (7.1)
7.2. The Project:Ghazi Barotha Hydropower Project is located on the Indus river downstream of
Tarbela Dam. The Project utilizes the hydraulic head available between the tailrace at Tarbela
Dam and the confluence of the Indus and Haro Rivers for power generation. In this reach
Indus River drops by 76 m in a distance of 63 km. This Project possesses the minimum of
environmental and social impacts.
Ghazi Barotha Hydropower Project consists of three main components. Barrage, Power
Channel and the Power Complex. The Project utilizes the normal Tarbela Dam releases to
provide year round maximum power generation during the daily hours of peak demand,
including the months of May and June when reservoirs of Mangla and Tarbela Dams are
historically at their lowest. This enhances the capacity of the whole power system by
providing much needed relief in the form of cheap hydro energy.
7.3. The Barrage:
The Barrage located 7 km downstream of Tarbela Dam, provides a pond which
re-regulates the daily discharge from Tarbela by diverting the flow into the Power
Channel. The principal features include 20 No. standard bays, 8 No. under sluices and
8 No. head regulator bays in addition to rim embankments, fuse plug and dividing
island.
The Barrage can pass the design flood of 18,700 comics, equivalent to the flood of record,
through the standard bays and under sluices at the normal pond level of El. 340 m. The fuse
plug has been provided to pass the extreme flood up to the capacity of Tarbela’s spillway and
tunnels equaling 46,200 comics.
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7.4. The Power Channel:
Ghazi Barotha Hydropower Project holds the record for the biggest concrete lined
channel in the world. The channel is 51.90 km long with a concrete lining and design flow of
up to 1600 comics at a water depth of 9 m. It has a bottom width of 58.4 m.
The Power Channel has a nearly contour alignment with hills on the left side and the land
naturally draining towards the Indus River on the right side. The Power Channel intercepts
fifty three nullahs (natural drains) of which twenty-seven major nullahs have been passed
over the Power Channel by providing super passages. The remaining twenty four minor
nullahs are being discharged into the Power Channel through individual inlets whilst one
nullah is passing underneath the channel through a culvert.
Figure ghazi brotha chennel (7.2)
7.5. Mechanical and Electrical Equipment:The installed power generating capacity is 1450 MW consisting of five units each of
290 MW. The units have a design flow of 400 comics at optimum gate opening and 460
comics at full gate opening for a design head of 69 m.
The principal items of power equipment are as follows:
Five Francis turbines each with a 290 MW generator which together have a combined power
generating efficiency of 94%.
Five three-phase banks of transformers, each single-phase unit being 107.5 MVA.
500 KV conventional outdoor switchgear configured in one-and-a-half breaker arrangement.
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12 cranes with lifting capacities from 6 to 450 tons.
With a project which is spread over such large area, it was considered necessary both for
safety and efficiency that it should be monitored and controlled centrally. This has been
achieved by providing two independent distributed control systems (DCS) one each at the
Barrage and Power Complex which share information through an optic fiber cable link.
7.6. Project Financing:
The PC-I of the Project was approved by Government of Pakistan in July 1994 at a total
cost of Rs. 89840 million. The total cost which has been incurred on the Project is Rs. 96957
million.
The Project has been funded by WAPDA supported by the following international lending
agencies:
World Bank
Asian Development Bank
Japanese Bank for International Cooperation
Kreditanstalt fuer Wiederaufbau (KfW)
European Investment Bank
Islamic Development Bank
This Project is an important component of Pakistan’s power system. The least cost status of
the Project remains valid for the full range of sensitivity analysis performed. The Project has
highly favorable economic parameters; it has an EIRR of 22.19% and FIRR of 13.76%. The
economic and financial returns have shown that the Project forms a part of the least cost
generation expansion plan for Pakistan.
8. Rawal Dam:
8.1. Introduction:Rawal Dam (Rawal Lake) is an artificial reservoir in Pakistan that provides the
water needs for the cities of Rawalpindi and Islamabad. Rawal Lake / Dam is a very
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beautiful lake located in Islamabad Park Area. The lake is situated in the Margalla Hills
National Park. A dam was built on this lake across Korang River in 1962 called Rawal
Dam. It has a storage capacity of 47,500 acre feet and covers 3.5 square miles. Two
canals are derived from the dam. Left Bank Canal and the Right Bank Canal. These
canals run through the Punjab and irrigate a major area. It is an ideal place for picnic,
fishing and boating. There is a terraced garden on the lake side. The highest point in
the garden offers a great view of the lake, Margalla and Murree hills. Red Onion &
PTDC restaurants give snack bar facility.
Figure RAWAL DAM (8.1)
8.2. Salient feature of Rawal damLocation: Margalla Hills National Park
Type: reservoir
Catchment area: 106.25 sq mi (275.2 km2)
Basin countries: Pakistan
Surface area: 8.8 km
Max. depth: 102 ft (31 m)
Crest level: 1,742 ft (531 m)
Crest length: 700 ft (210 m)
Maximum height: 133.5 ft (40.7 m)
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8.2.1. Spillway:Type: Ogee gated structure
Discharge Capacity: 82000 ft³/s (2,300 m³/s)
8.2.2. Reservoir:Area: 3 square miles (7.8 km2)
Maximum depth: 102 feet (31 m)
Live storage: 43,000 acre feet (53,000,000 m3)
Dead storage: 4,500 acre feet (5,600,000 m3)
Gross capacity: 47,500 acre feet (58,600,000 m3)
8.2.3. Canals:Left bank canal: length 5 miles (8.0 km)
Capacity: 40 ft³/s (1.1 m³/s)
Right bank canal: length 1.5 miles (2.4 km)
Capacity: 70 ft³/s (2.0 m³/s)
8.2.4. Drinking water supply:Rawalpindi: 19.5 million US gallons per day (74,000 m3/d)
Islamabad: 2.5 million US gallons per day (9,500 m3/d)
8.2.5. Command area:Agriculture: 500 acres (2.0 km2)
9. References: http://pecongress.org.pk/ http://nceg.upesh.edu.pk/ www.waterinfo.net.pk www.wapda.gov.pk http://en.wikipedia.org/ SLIDESHARE.NET