environmental aspects tehri dam final

GUJARAT TECHNOLOGICAL UNIVERSITY

SARVAJANIK COLLEGE OF

ENGINEERING & TECHNOLOGY,

SURATDr. R. K. Desai Road, Athwalines, Surat – 395 001, Gujarat, INDIA

A Project report on

ENVIRONMENTAL ASPECTS OF

TEHRI DAMUnder subject of

HYDROLOGY

B.E.3, Semester - 5

Submitted by:

Sr No. Name Enrollment no.

1 Jariwala Khushboo 130420106023

2 Parikh Aayush 130420106036

3 Patel Ekta 130420106040

4 Viradya Pruthika 130420106055

5 Donga Jeet 130420106061

6 Patel Devang 120420106052

Guided By:-

Prof.Sapan Parekh

1 REPORT : ENVIRONMENTAL ASPECTS OF TEHRI DAM

INDEX

1. INTRODUCTION

1.1 HISTORY

1.2 TECHNICAL DETAILS

1.3NEW TEHRI

1.4 THDC INDIA LTD.

2. CONSTRUCTION OF TEHRI DAM- STUDY OF FORCES AND GEOLOGICAL ASPECTS

2.1 ROCKS AND EXTERNAL MATERIALS USED- STUDY & CONSCEQUENCES

2.2 FILLING THE EARTH- ROCK FILLED TEHRI DAM

2.3 CHOICE OF DAM SITE

3. ENVIRONMENTAL IMPACTS

3.1 ENVIRONMENTAL IMPACTS

3.2 ENVIRONMENTAL IMPACT ASSESSMENT

3.2.1 MEASURES FOR ECOLOGICAL IMPACTS

3.2.2 MEASURES FOR SOCIAL IMPACTS

4. BENEFITS TO NATION AND NEARBY REGION

5. DISADVANTAGES AND RISK

5.1 SEISMIC RISK

5.2 DISPLACEMENT AND REHABILITATION

5.3 ENVIRONMENTAL CONSCEQUENCES

5.4 CORRUPTION

5.5 OVERSHOOTING ECONOMIC COSTS

5.6 URBAN ISSUES

5.7 POLITICAL CONFLICT

6 REHABILITATION PLAN

6.1 BROAD FEATURES OF PLAN

6.2 IMPROVEMENTS OF R&R PACKAGE

6.3 IMPROVEMENTS BY HRC

6.4 IMPROVEMENTS AFTER HRC


6.5 REHABILITATION PACKAGE

6.6 INSTITUTIONAL MECHANISM

7. FUTURE SCOPES

8. CONCLUSION

9. LIST OF FIGURES

10. REFERENCES


CHAPTER 1: TEHRI DAM

1.1 Introduction

Tehri Dam is a multi-purpose rock and earth-fill embankment dam on the Bhagirathi

River near Tehri in Uttarakhand, India. Tehri is located 200 miles north east of Delhi,

in the state of Uttaranchal. With a height of 260 meters (855 feet), the dam is the fifth

tallest in the world and the tallest dam of India. The Tehri Dam withholds a reservoir

for irrigation, municipal water supply and the generation of 1,000 megawatts

(1,300,000 hp) of hydroelectricity.

Fig 1.1.1

The construction of the dam started in 1978 and phase 1 was completed by 2006. The

cofferdam was completed in 1996. The construction cost was $1 billion. The owner of

the dam is THDC INDIA Ltd. Tehri Hydro Development Corporation (THDC) is a

joint venture of the Government of India and the state government of Uttaranchal. In

1986 an Indo-Soviet agreement brought Soviet expertise and aid of approximately $416

million to the project. In 2001 the German export credit agency Hermes guaranteed

loans to Voith Siemens Hydro to provide generating equipment for Tehri.

Tehri Development Project also includes the 97 meter high Koteshwar Dam, under

construction 14 miles downstream of Tehri Dam. The 400 MW Koteshwar Dam will

either completely or partially submerge 16 villages. It provides 270 million gallons of

drinking water per day to Uttaranchal, Uttar Pradesh and Delhi. It also gives

stabilization to existing irrigation on 600,000 hectares land.

From its inception, Tehri dam has been opposed due to concerns over its

environmental and social impacts, and its ability to withstand earthquake damage. Tehri

Dam officials have also been implicated in several cases of corruption.

Tehri Hydro Power Complex (2400 MW), comprise the following components:


o Tehri Dam & Hydro Power Plant (1000 MW)

o Koteshwar Hydro Electric Project (400 MW)

o Tehri Pumped Storage Plant (PSP) (1000 MW) 5

The two lower tunnels of the dam were closed in December 2001 submerging the

main bridge leading to Tehri town and nearby areas. The last two tunnels, which are at

a higher level, were closed by December 2002.The total capacity of the dam is 4.0km3

1.2 History

The timelines for the Tehri Dam project are summarized as follows:

1961 - A preliminary investigation for the Tehri Dam Project was conducted.

1972- Design was completed with a 600 MW capacity power plant based on the

study.

1978- Construction began after feasibility studies but was delayed due to financial,

environmental and social impacts.

1986-Technical and financial assistance was provided by the USSR but this was

interrupted years later with political instability. India was forced to take control of the

project and at first it was placed under the direction of the Irrigation Department of

Uttar Pradesh.

1988-The Tehri Hydro Development Corporation was formed to manage the dam and

75% of the funding would be provide by the federal government, 25% by the state.

Uttar Pradesh would finance the entire irrigation portion of the project.

1990-The project was reconsidered and the design changed to its current multi-

purpose.

2006 - Construction of the Tehri Dam was complete

2012 -. The second part of the project, the Koteshwar Dam was completed.

February 2016- The pumped storage power plant is slated for commissioning.

Uttarakhand state’s Tehri Hydroelectric dam is a massive 261-meter rock-and-

concrete power plant that supplies large amounts of electricity as well as drinking and

irrigation water to the greater part of northern India, including the country’s second-

most populous city of Delhi.

It has also created a large reservoir that inundated the town of Old Tehri, along with

approximately 110 villages, displacing between 50,000 and 100,000 people (Joshi

2006).


The recently constructed city of New Tehri was designated for some of these

displaced people who lost their homes and businesses.

These people, accustomed to their long-established life along the Bhagirathi and

Bhilangna Rivers, now adapt to a new environment on the side of a mountain which is

not directly accessible to the river.

1.3 Technical Details

Fig 1.3.1

Type of Dam: Embankment, earth and rock-fill

River: Bhagirathi River

Height: 260.5 m (855 ft)

Length: 575 m (1,886 ft)

Width (Crest): 20 m (66 ft)

Width (Base): 1,128 m (3,701 ft)

Spillway Type: Gate controlled

Spillway Capacity: 15,540 m3/s (549,000 cu ft/s)

Total Capacity: 4.0 km3 (3,200,000 acre·ft)

Surface Area: 52 km2 (20 sq mi)

Turbines: Vertical Francis turbines

Installed Capacity: 1,000 MW (1,300,000 hp) Max. Planned: 2,400 MW


The installed hydro capacity is 1,000 MW along with an additional 1,000 MW of

pumped storage hydroelectricity. The lower reservoir for the pumped-storage plant is

created by the Koteshwar Dam downstream.

The Tehri Dam and the Tehri Pumped Storage Hydroelectric Power Plant are part of

the Tehri Hydropower Complex which also includes the 400 MW Koteshwar Dam.

The complex provides irrigation to an area of 270,000 hectares (670,000 acres),

irrigation stabilization to an area of 600,000 hectares (1,500,000 acres), and a supply

of 270 million imperial gallons (1.2×106 m3) of drinking water per day to the

industrialized areas of Delhi, Uttar Pradesh and Uttarakhand.

1.4 New Tehri

The newly built well planned modern town nestles at a height of 1,550 metres

overlooking the massive artificial lake and Tehri dam built on the Bhagirathi and

Bhilanganariver. It has taken over as district headquarters of TehriGarhwal from the

Old Tehri town and was established to rehabilitate the Old Tehri, which was submerged

into the waters of the Tehri Dam. In fact New Tehri is considered to be Asia's most

comprehensive and successful rehabilitation program. The gleaming township has

developed into a lovely hill resort.

General Information

o Altitude- 1550 mts. To 1950 mts.

o Climate -Min. Temp. 40 C, Max. Temp. 300 C

o Language- Garhwali, Hindi & English

o Air – Nearest is Jollygrant 93 kms

o Rail – Rishikesh is the nearest railway station, 76 kms.

Road – New Tehri is well connected by road to all important stations of Garhwal

Division like Dehradun, Mussoorie, Haridwar, Pauri, Rishikesh, Uttarkashi etc. Private

Taxiesabd jeeps are available for trips to nearby towns of chamba&Tehri. Bus service

connect to New Tehri to Tehri, Rishikesh, Haridwar, Dehradun, Mussoorie.


1.5 THDC India Ltd.

THDC India Limited (Formerly Tehri Hydro Development Corporation Limited), is a

company jointly promoted by Government of India and Government of Uttar Pradesh.

The equity is shared in the ratio 75:25 between GoI and GoUP for the power

component. It was incorporated in July’88 to develop, operate and maintain the 2400

MW Tehri Hydro Power Complex and other Hydro Projects. THDC India Limited is a

Mini Ratna Category-I Enterprise.

At present the company has two power plants in operation namely Tehri Dam (1000

MW) and Koteshwar Dam (400 MW).The corporation has grown into a multi –Project

organization with projects spread over various states as well as the neighboring country,

Bhutan.


CHAPTER 2: CONSTRUCTION OF TEHRI DAM: STUDY OF FORCES

AND GEOLOGICAL ASPECTS

2.1 Construction of Tehri Dam- Study of Forces and Geological Aspects

The Tehri dam rocks are 65% clayey and are thus highly fractured and ridden by

earthquake fault lines. Such fault lines could be reactivated by the sheer load of the water.

There are ominous signs of a steep increase in the frequency of earthquakes not only close

to the dam but far away from the dam.

Alternatively, the swelling of the soil layer can impose a pressure on the rock-layers

and tend to crack them. Moreover, when the wet soil layers dry they shrink. This

expanding-drying cycle can result in the rock-layer cracking further and add to the

crushing, sand-forming, mechanisms.

The Tehri dam is built 1.5 km downstream of the confluence of Bhagirathi (starting

from Gomukh) and the Bhilangana river. The rocks around the river gorge are mainly of

the Chandpur phyllite kind. Chandpur phyllite are folded and are of grayish green color

probably of the kind shown.

The rocks here have undergone various magnitudes of tectonic deformation and have

been summarized in Fig 2.1.1, right. Grade I Phyllites are massive in character and are

predominantly arenaceous (describing rocks or deposits that are composed of sand grains

or have a sandy texture). Phyllites of Grade II are conspicuously banded with alterations of

arenaceous and argillaceous (sedimentary rock that is made up of clay or silt particles) and

Phyllites of Grade III are mainly argillaceous and are generally weathered, thinly foliated,

sheared and shattered. Sheared Phyllites are the weakest bed-rock unit in the gorge. When

the Tehri dam tunneling was started there was very little actual in-tunnel engineering

experience available anywhere, leave alone the Himalaya.


Fig 2.1.1

An L-shaped crack developed on Raika hills of Tehri (Fig 2.1.2, left), which has since

then become notorious for many accidents. These hills form part of the reservoir around

Tehri’s dam. The image of this crack has two features of interest. It shows the vulnerable

properties of the hill slope that consists of cracked slabs. The figure on the right could

indicate why. The picture on Fig 2.1.2 right depicting the crack occurs for concrete and

foundations where a foundation stair-steps down to follow a hill-slope and probably

shrinkage cracks.

Fig 2.1.2

2.2 Filling the Earth-Rockfill Tehri Dam

A major input that is required before a dam is built is the permeability (hydraulic

conductivity) of rock masses. When there is a wide variation in the permeability (as it is

for the Tehri rocks) dependence on an average value simply will not suffice especially

if one knows that collapse takes place at the weakest link.ld not have been used for the

top cover.


The discontinuity apertures in the rocks are the most important factor for the rock’s

hydraulic conductivity. The changes in apertures due to stress could have marked effect

on the hydraulic conductivity so that one requires in situ tests such as, what is called,

Lugeon tests.

One of the main drawbacks of the Lugeon test is that each test it is limited to an area

of only ~ 100 m2 rocks near the dam site could not be expected to give reliable

engineering information and a height of ~ 10m. In short, results of Lugeon tests on the

Phyllite.

Fig 2.2.1

A cross section of the Tehri dam is given in Fig 3.2.1. The length across the valley at

the crest is ~ 575 m while the base width in the upstream-downstream direction is ~

1000 m at the base and nearly 20 m at the crest. The design requires an impervious core

made up of clayey materials and a shell of graded gravel that is topped with blasted

rock which should be massive and mostly quartz. However there is no certified

expertise on the stability of the dam to earthquakes, the stability of the surrounding

slopes to mudslides and collapse as well as to settlement.

The fragile nature of the rockfill as compared to the requirement of rocks surface size

between 25 mm to 600 mm size or between 1” and 2 ft size as per the drawing in Fig 9

is not satisfied.


The rocks used for rockfills were obtained from Old Dobata area that lies

approximately 5 km upstream of dam site on the right bank of Bhagirathi and new

Dobata borrows in Tehri Garhwal district. These rocks are technically described as

tabular grains, equigranular, granoblastic (fragments are irregular) in texture, and

metamorphosed from sedimentary rock sandstone. The main difference between the

New Dobata borrow and the Old Dobata borrow is that the former had nearly 99%

quartz and were white in color while that from the Old Dobata borrow had 96% quartz

with more garnet and mica. This suggests that the rocks from the old Dobata borrow

were more clayish. The old Dobata borrow rocks should not have been used for the top

cover

2.3 Choice of dam site

Fig 2.3.1

Because of the very nature of the requirements for tall dams on main rivers,

geological boundaries such as thrust lines or major faults are not uncommon, since they

provide the necessary geomorphologic features. Major fault lines are known to exist at the

Tehri dam site.

Some of the features that require to be taken into account are given in Fig 11.Perhaps

the first and most important requirement these is that the rocks adjacent to the dam or on

the sides of the river should be stable to sliding when wet. The slopes of the banks of the


river are dominated by Debris or remains of broken rock because of high levels of

fracture, and faulting (of the earthquake kind) and sedimentation.

As discussed above hydro geological reasons such as low grade phyllitic rocks in the

abutments and rim slopes with increased soil moisture due to soaking by the increased

height of the reservoir could lead to a sliding of bedrocks and cause large landslides.

These landslides would increase the sedimentation rate and drastically reduce the dam’s

life for power generation or irrigation.

Because of the high levels of fracture and sandy character the slopes of the hills are

expected to be close to the critical angle of 35o of the slope. The lower regions of the

surrounding hills have a slope considerably larger than 35o they soaked and wet as when

the reservoir is full. If the entire slope was to attain this critical angle , the level of the

bottom of the river would rise roughly to 650-660 ft. Flood waters from higher ranges

would fill the river up further. This is what is found for the higher parts.


CHAPTER 3 ENVIRONMENTAL IMPACTS & ASSESSMENT

3.1 Environmental Impacts

The Tehri Dam has been the object of protests by environmental organizations and

local people of the region. The construction of the dam has resulted in destruction of

houses of thousands of people. The relocation of more than 100,000 people from the

area has led to protracted legal battles over resettlement rights, and ultimately resulted

in the project's delayed completion.

Since 2005, filling of the reservoir has led to the reduced flow of Bhagirathi water

from the normal 1,000 cubic feet per second (28 m3/s) to a mere 200 cubic feet per

second (5.7 m3/s). This reduction has been central to local protest against the dam,

since the Bhagirathi is considered part of the sacred Ganges whose waters are crucial to

Hindu beliefs.

At some points during the year, the tampering with Bhagirathi waters means this

tributary stops flowing. This has created resentment among many Hindus, who claim

that the sanctity of the Ganges has been compromised for the generation of electricity.

Though the officials say that when the reservoir is filled to its maximum capacity the

flow of the river will again become normal. In spite of concerns and protestation,

operation of the Tehri Dam continues.

Impacts on the surroundings due to the dam are:-

a. Change in the (i) water chemistry, especially with respect to dissolved oxygen

and (ii) turbidity of water.

b. Impact on biodiversity, i.e., flora and fauna of the area.

c. Obstruction of movements of migrating fish species during breeding season.

d. Rivers carry a lot of sediment, which on construction of a dam, will be locked

up behind the dam wall. The collected silt in the reservoir eats away the capacity

of the reservoir. This impact of reducing the capacity and life of reservoir was

studied.


e. Impact of water accumulation on the upstream side of the dam, which causes

inundation of land including forest-land.

f. Since 109 villages (full or partial) and Tehri town (full) were affected and the

residents were to vacate their ancestral homes and agricultural fields, a scheme

was prepared, to resettle these people, with the idea to improve their living

standard, keeping their social bonds intact.

g. Problem of water-logging and salinity of the land in the command area.

3.2 Environmental Impact Assessment

Based on the impact assessment studies, various mitigating measures were designed. In

order to mitigate probable impacts following measures/safeguards were taken:

3.2.1 Measures for Ecological Impacts

Compensatory Afforestation-

Forest land of 4193.813 ha.were diverted for construction of Tehri Dam Project and

Koteshwar Project (in the downstream of Tehri Project). This forest-land included the

land used in construction of Project, Project colonies, resettlement colonies and filling

of reservoir.

Catchment Area Treatment-

In order to reduce soil erosion (for reducing sedimentation in the reservoir), the Tehri

Project had completed the Catchment Area Treatment (CAT) in the entire degraded

catchment, in areas of ‘High’ and ‘Very High’ erosion class.

Command Area Development-

Command Area Development Plan had been implemented by the Irrigation

Departments of the State Governments of Uttarakhand and U.P. In order to mitigate the

likely problem of water-logging and salinity, the network of field channels and drains

were developed.


Flora-

In CAT works, the species as recommended by Botanical Survey of India (BSI), based

on their flora study of the area, have been planted. A botanical Garden in an area of

14.28 ha.has also been established and plantation of special species coming under

submergence has been completed, so as to preserve important flora of the region.

Fauna-

Faunal studies were got conducted through Zoological Survey of India (ZSI), for fauna

affected due to formation of reservoir. As per ZSI studies there will be no adverse

impact on mammals, Aves (Birds), Reptiles (Snakes and Lizards), Amphibian (Frogs &

Toads) and Pisces (Fresh Water Fishes) due to proposed reservoir except on Tor-

Putitora (Mahseer Fish).

Water Quality Maintenance-

The water quality modeling study had been carried out, which concluded that no

specific measures are required and there would be no adverse effect on the water

quality due to impoundment. However, the work on water quality monitoring on Tehri

Reservoir, both upstream and downstream is being carried out at 5 monitoring stations.

Green Belt-

A green Belt have been planned to be created along the rim of the reservoir between

850 m above MSL and 1050 m above MSL. The idea for developing the green belt is to

check soil erosion and resultant siltation of the reservoir; to protect and regenerate the

vegetation in the rim area; to increase the natural beauty of the landscape.

Impact on Human Health-

A comprehensive study of the potential health impacts of Tehri dam was conducted.

National Malaria Eradication Programme (NMEP) and Malaria Research Centre

(MRC) carried out detailed field investigations of the area. Action-plan for

preventive/mitigation measures is being implemented.


3.2.2 Measures for Social Impacts

3.2.2.1 Better Quality of Living:

In order to achieve the objective of ‘better quality of life’ following steps were taken

through R&R programme. The idea is to ensure that settlers are provided opportunities

to become established and economically self-sustaining in shortest possible period.

Urban:-

Better quality of living. Urban population was provided better facilities like better

and wider road network, sewerage system, hospital with enhanced capacity,

stadium and other amenities, scope for expansion, planned growth.

Larger school buildings with hostel accommodation will enable their

management to enhance their capacities. A larger University campus has been

constructed in addition to a college keeping in view the future needs of the

region.

More employment opportunities due to high tourism potential and industries

likely to come up due to excellent infrastructure available in NTT and

surrounding areas.

100 economically backward and houseless persons now have free housing at

NTT, of which they would become owners.

Rural:-

The all-round development of the area would lead to prosperity, better

infrastructure and better quality of life.

New road network and taped drinking water supply save the time of people which

can be utilized for other works.

Due to the increase in land holding, i.e., against the existing less than 1 acre

average rain fed land holding, to the allotted 2 acres well irrigated and developed

land, yield and total income is expected to increase. Due to payment of House

Construction Assistance to PAFs, the PAF have been able to construct better

houses, which has resulted in improvement in their living standards.


Landless agricultural labors have also become owners of 2 acres of agricultural

land and independent houses.

People who will not be shifted (above the reservoir level) shall be benefited due to

Catchment Area Treatment, tourism, fishery development and horticulture, apart

from infrastructural development.

3.2.2.2 Employment & Income Generating Schemes:

Employment:

For employment in the THDC, preference was given to the dependents of the

project affected families, particularly in the category of workmen & supervisors,

subject to vacancies and their meeting the necessary laid down qualifications and

experience requirements.

Apart from this, the contractors deployed on the Project a sizable work force form

the local area.

In order to provide gainful employment to the local population, THDC awarded

small value contracts to the local people.

For treatment and soil conservation work in the Catchment Area, the forest and

other concerned departments, have employed more persons.

With the construction of the New Tehri Town at a high altitude, formation of

reservoir, better road network etc., it is expected that there will be an all round

development in the area, which will further enhance the employment

opportunities due to setting up of new non-polluting industries, better tourism

opportunities through developmental activities.

With a view to encourage the dispossessed families taking to useful vocations,

like poultry farming, floriculture, pisci-culture, animal husbandry, handicrafts,

khadi work etc. the Government agencies have taken up various self-

employment / income generating schemes.


Income Generating Schemes:

Since it was not possible to give direct employment to all unemployed youth from

PAFs in the project, a group was formed in THDC for helping the resettled

families to take advantage of various schemes of Self-employment and Income

Generation being implemented by various Govt. and Semi Govt. agencies. The

group organized various activities for the benefits of PAPs as under-

o Organized awareness camps at Athoorwala and KhandRaiwala so that

PAPs should come forward as rural entrepreneurs. The group invited the

officials of various State/Central Government agencies like Khadi Village

& Industry Commission, State Horticulture & Food Preservation Dept.,

State Sericulture Dept., State Fisheries Dept., Lead bank & Poultry Dept.,

etc.

o Being influenced with these awareness programmes PAPs started showing

the interest in various schemes. PAPs interested for Mushroom cultivation

requested the group for organizing training. Group arranged training in

three batches through UP State Horticulture & Food Preservations Dept.


CHAPTER 4 BENEFITS TO THE NATION AND NEARBY REGION4.1 Benefits to Nation

Fig 4.1.1

2400 MW of environment friendly Peaking Power (6532 MU of Annual Energy) –

1000 MW (3532 MU of Annual Energy) in Stage-I. This is bound to lead to industrial

and agricultural growth in the Northern Region.

12% power free to home state, apart from Power as per their share, where distress is

caused by setting up the project at the specific site.

Additional energy form downstream run-off-the river schemes.

Irrigation of 2.7 lakhs ha. of new area, besides stabilization of irrigation in already

irrigated 6.0 lakhs ha.

300 cusecs (162 million Gallons per day) of water supply to Delhi, which will meet

drinking water need of 4 million people.

200 cusecs (108 million gallons per day) of water supply to UP which will meet

drinking water need of about 3 million people.

The project would lead to all round development of the region through better

infrastructure and easy availability of electricity, particularly peak time power

Flood moderation during monsoon by way of storage of excess water.


Fig 4.1.2

Development of pisciculture.

Integrated development of the catchment area.

4.2 Benefits to Nearby Region

Development of Hill Station- For shifting of old Tehri Town a new modern town

named as New Tehri Town (NTT) has been developed at a height of 1550-1850 m.

above MSL which is at height almost similar to that of Mussorrie. This town has all

modern facilities.

Better Road Network- Due to construction of Project, roads of the area have been

widened and improved which made communication easier and comfortable. Rishikesh-

Chamba-NTT roads have also been widened and geometry have been improved which

has resulted in reduction of journey time.

Education- For shifting of educational institutions of Old Tehri Town, larger buildings

with modern facilities were constructed so that more number of students can be

accommodated, while having scope for further expansion in future.

o In most of the educational institutions, Hostel facilities for 860 students have

been provided, though it did not exist in Old Tehri. Thus, more students coming

from the nearby areas will be benefited as NTT is expected to develop as a nodal

center for education in the region.

o Against existing degree college running in Old Tehri Town, a degree college

and a big university campus has been constructed at Badshahithaul which can

accommodate 400 residential students and also the teaching staff.


o In addition, for the students of villages who were studying in Old Tehri, 4 degree

colleges have been constructed at project cost. Similarly, against one Inter

College in Old Tehri, one Inter college in N.T.T. and 4 Inter colleges in villages

have been constructed.

Health-

o Against 22 beds Hospital of Old Tehri, 75 beds Hospital have been

constructed at New Tehri Town, with modern medical facilities. In addition, 5

numbers Primary Health Centers with indoor treatment facilities (totaling to 70

beds) have been constructed at Project cost.

o To provide hygienic conditions, treated water is supplied to houses and a

central sewerage treatment plant has been constructed with a properly designed

network of sewer lines connecting houses and other buildings of the town.

Electrification- For improving electricity distribution system in nearby rural areas, 3

nos. 33 KV sub-stations have been constructed and network of LT/HT transmission

lines have also been made at project cost.

Drinking water facilities- 54 numbers drinking water schemes in rural areas and New

Tehri town have been constructed and made operational at Project cost. They shall now

be operated and maintained by respective agencies.

Shifting of District Head Quarter- With the shifting of district head quarter from

Narendra Nagar to New Tehri, a distance of about 60 km have been reduced for the

urban and rural population of Tehri resulting into saving of time and inconvenience to

the public having work at district level offices.

Setting of New Industries- The New Tehri Town is very suitable for setting up of

Non-pollutive Industries due to its better climate and excellent communication

facilities. As the power is now easily available after the construction of dam, more

factories are likely to come up as NTT has excellent infrastructure as well.


Tourism- The New Tehri Town is a pre-planned hill town with all modern facilities.

Hence, it is expected to develop as a major tourist hill station in near future.

By creation of lake due to the impoundment of the reservoir of Tehri Dam, scope for

water sports will be there.

Due to wider and improved roads, communication has become easier which is very

important for development of tourism .Due to tourism development, Hotel Industry in

the area will increase, which will further help the local people in getting employment.

Commercial Centre- New Tehri Town market is developing as a market for adjoining

towns/villages in the region and is expected to come up as a nodal commercial centre in

the region because of its vocational advantage and better infrastructure facilities like

roads, telecommunication and properly designed shopping centre. The shop area is also

larger and made of RCC structure and has greater storage capacities for goods.


CHAPTER 5: DISADVANTAGES AND RISKS

5.1 Seismic Risk -

The design of the dam was finalized in the 1960s when scientific understanding

of seismic hazards and seismic engineering solutions were far less advanced than

today. Tehri Dam is situated in the highly active Central Himalayan Seismic

Zone. It is designed to withstand earthquakes of up to 7.2 on the Richter scale

although experts predict that earthquakes of magnitude 8.5 or more could strike

this region.

If the dam were to burst, several major towns downstream of the dam with a total

population of over half a million people could be wiped out Landslides are

common on the steep slopes above Tehri’s reservoir. A major landslide into the

reservoir could cause a huge wave, which could overtop the dam and cause

massive damage downstream. It would bury the towns of Rishikesh, Hardwar,

Bijnor, Meerut, Hapur and Bulandshahar within hours and devastating large areas

of the Gangetic Plains.

Fig 5.1.1


5.2 Displacement and Rehabilitation

Although land acquisition started in 1979, resettlement of affected people is far

from complete. There is no master plan for rehabilitation nor even a clear

estimate of the number of people affected. Past estimates range from 67,500 to

97,000. According to the 2002 Status Report of the Public Works Department of

Tehri, the Dam displaced 12,547 families.

This estimate excludes a large number of people who lost their lands but have not been

officially recognized as project-affected. Among those officially recognized, only half

of the fully affected and very few of the partially affected families have been resettled.

In most cases the land allotted is of poor quality or with multiple ownership claims.

5.3 Environmental Consequences:

The highly absorbent shale, customary in the valley, makes the slopes

susceptible to frequent slides. As the reservoir fills, landslides from above the

submergence line further heighten and compound the siltation problem.

In fact, landslides are a prevalent problem as a result of the deforestation and road-

building. The construction obstructs the flow of the river impeded Ganges as a

result of which the entire Gangetic valley.

Silt brought down from the upper reaches of the catchment and containing

valuable mineral deposits is caught behind the dam strangling the holy river. This

has enormous consequences for all who live on the Gangetic plain. It halts the

flow of this natural fertilizer could cause severe agricultural problems in the

foreseeable future, possibly even famine.

The residents of Old Tehri lived in a river valley at an average altitude of 1,115 feet

above sea level. Since relocation to New Tehri, the community has had to adapt to

life at 5,085 feet.

The extreme elevation change has resulted in radical environmental differences

that include wider daily temperature ranges and a reduction in daily sunlight.

Though daytime temperatures can still be warm, as high as 105º F in the summer,

it is the conditions at night that offer the biggest change. Cold temperatures and

blistering wind drive people from the streets shortly after the sun falls behind the


mountain, which occurs not long after 4 p.m. during the winter.

The higher altitude of New Tehri has also resulted in a lengthened winter

and introduced the possibility of regular snow, since temperatures at the

new site commonly fall below freezing (Baruah and Sabhlok 1994).

Fig. 5.3.1

5.4 Corruption

The Central Bureau of Investigation is currently investigating six cases of corruption

against high-ranking officials of THDC for embezzlement of public money. The

Hanumantha Rao Committee report expressed concern about the high incidence of

corruption in the rehabilitation process.


5.5 Overshooting Economic Costs:

The projected cost of Tehri Dam had gone up from $612 million in 1994 to $1.2

billion in 1999. A Cost benefit analysis commissioned by the Indian National Trust

for Art and Cultural Heritage (INTACH) concluded that the construction costs for

Tehri are twice the projected benefits.

The INTACH study predicts the useful life of the dam would be reduced to 62 years

by the huge volumes of sediment that will be trapped in its reservoir. A recent study

shows that the cost of electricity per unit from Tehri is almost twice the average cost

of power supply in the neighboring states of Punjab, Himachal Pradesh and Jammu

and Kashmir.

Fig. 5.5.1

5.6 Urban Issues :

New Tehri is a planned city that was designed to host 25,000 people’s homes and

businesses. Yet its citizens describe the new city as awkward, cold, and unpopular.

Already facing overwhelming opposition from the displaced citizens, the government

designed it in a way that would appease the upset immigrants.

Within New Tehri, residents have expressed a concern over transportation problems

that exist both within the community as well as with neighboring cities and towns.

The city is a split-level town with a lower half of western block-style residential

housing and an upper half with markets, a school, and government facilities.


The main intra-city accessibility problem concerns the difficulty of travel between

the upper and lower parts of the city, resulting in bottlenecking of main routes.

Additionally, walking within the city has been hampered due to its larger size and

elevation changes present throughout the city.

Furthermore, the construction of the dam also cut the local region in half, with the

reservoir serving as the knife. With the existing bridges over the Bhagirathi being

submerged, cities directly to the east of New Tehri have virtually no access to their

district capital.

5.7 Political Conflict:

The resettlement policies and the structural flaws of the dam hence provoked civil

protests, lawsuits and international attention that have stalled the project during its

construction period.

The Tehri project was unsuccessfully challenged in the Supreme Court in the writ

petition filed by the Tehri Bandh Virodhi Sangarash Samiti (TBVSS) in 1985. In

1987, the Indian National Trust for Art and Cultural Heritage (INTACH), an

'intervenor' in the petition and a leading non-governmental organization in the field of

conservation, sponsored an independent assessment of the economic feasibility of the

dam.

The principal findings of the multi-disciplinary team that conducted the appraisal was

that the benefit to cost ratio of the Tehri dam, after calculating social and

environmental costs and benefits, workout to 0.56 to 1., well short of the 1.5:1 ratio

adopted by the planning Commission to sanction such projects.

In addition, the Soviet Union agreed to help fund the project with loans at concession

terms and as part of the agreement reviewed the proposed project and made several

findings. The most important one was the high seismicity of the Tehri area had not

been adequately taken into consideration by Indian planners.

Also, the Indian government had projected a useful life of 100 years, the actual figure

would be 62 years or less. Finally, while the authorities put the number of displaced

people, or oustees at 46,000, the INTACH team found that 85,600 people would be

displaced by the project.

The Supreme Court dismissed the petition in 1990 after a very limited enquiry.

Although the Environmental Appraisal Committee had unanimously concluded that 28 REPORT : ENVIRONMENTAL ASPECTS OF TEHRI DAM

the Tehri project should not be approved, the Central Government relied instead on an

opinion of the Department of Mines to convince itself and the court that the project

was sound.

The report of the high commission was again considered by the committee of

Secretaries in its meeting on 23rd April 1990. The committee of Secretaries found on

consideration of the report of the high level committee that the Tehri Dam as designed

was safe and the seismic potential of the site was taken into consideration by the

experts. Later on 12th May Dr. V.K.Gaur who had earlier agreed on the report, sent a

note of dissent and questioned the conclusion of the high level committee of experts,

in respect of the safety aspect.

The committee of Secretaries met again on 10th August 1990 and discussed the

recommendations of the high level commission along with the dissent of Dr. Gaur.


CH.6 REHABILITATION PLAN

The Rehabilitation Plan has been broadly divided into Rural Rehabilitation and Urban

Rehabilitation. Affected families under Rural Rehabilitation are categorized as "Fully

affected" or "Partially affected". The families whose 50% or more land is being acquired are

treated as fully affected. Those families whose less than 50% land is coming under

submergence are categorized as-"Partially Affected". In case of urban population of Tehri

Town, all 5291 families living in the Town as on the cut-off date of 06.06.1985 are treated

as fully affected. Under Rural Rehabilitation, there are 5429 Fully Affected families due to

Tehri Dam, which are to be rehabilitated. Another 3810 rural families are Partially Affected

and are not going to be displaced; they would be paid cash compensation for their land

under submergence.

6.1 BROAD FEATURES OF REHABILITATION POLICY

The basic principles that had guided the formation of the Rehabilitation Policy are:

● Rural oustees to be compensated through allotment of agricultural land or cash in lieu

theory.

● The rural oustees should be settled in large blocks so that the fabric of their social life

remains intact.

● Oustees or their representatives be involved to the extent possible in selecting the

rehabiltation centers.

● To the extent possible, consideration be given to the preference of the oustees for

settlementat a particular center.

● Community facilities be provided at each of the rural rehabilitation centers at the cost

of the project even if these did not exist at their earlier settlements.


6.2 IMPROVEMENTS IN R&R PACKAGE FROM TIME TO TIME

The rehabilitation work of the Project affected families was commenced by the Govt.

of U.P.when the Project was under them. The Rehabilitation Policy include the loction

of the new Tehri town. (NTT) had been evolved and decided by the State Government

of U.P. after interaction with the representatives of the local population. After the

incorporation of THDC, the rehabilitation work was handed over to the THDC in 1990.

6.3 IMPROVEMENTS BY HRC

On the demands for further improvements raised by the local population, the

Government of India in September, 1996 constituted a committee viz. Hanumantha

Rao Committee (HRC) to examine the Rehabilitation Policy of the Project and

suggest further measures/improvements etc.

The HRC submitted its recommendation to the Govt. in November 1997. The Govt. of

India after examining the recommendations of HRC, accepted certain additional

benefits/measures,which were incorporated in the Rehabilitation Policy of 1998.

The major recommendations of the Hanumantha Rao Committee, approved by the

Govt. in regard to rehabilitation of the affected population include definition of family

so as to make all major sons and major daughters who attained the age of 21 years on

19.07.1990 and dependent parent (Mother/Father) of the fully affected entitled land

owner eligible for ex-gratia payment of Rs.33,000/-, i.e. 750 days minimum

agricultural wage each; grant of house construction assistance to the urban land owner

families, linked with the progress of construction and shifting; allotment of one

constructed shop to the shop owners, recognition of the right of people, living in the

villages upstream of Tehri reservoir, over the water.


6.4 IMPROVEMENT AFTER HRC

After the Government decision of December 1998, on the recommendations of HRC,

following measures/ benefits were also agreed by the Government of India in consultation

with the State Government.

Rural

Enhancement of cash in lieu of land from Rs. 2 lakh to Rs. 5 lakh, house construction

assistance to fully affected house owners be given @ Rs. 1 lakh; increase in cash grants

for

shifting and purchase of seeds and fertilizers; cash grants ranging from Rs. 80,000 to Rs.

1,20,000 for rural shop owners depending upon their location; liberalization of eligibility

criteria for land allotment and made eligible, those land owners in rural area who sold their

part land after 1978, but before issue of Section 4(1) notification under Land Acquisition

Act.

Government has also allowed reconstruction and relocation of public properties situated

below EL 835 m in partially submergence villages, at higher level for population residing

above submergence level;arrangement for Ferry boat and cable car services for cut-off

area; and Heavy motor vehicle bridge across Bhagirathi river near Dobra village (this is in

addition to two medium motor vehicle bridges.

Urban

Amount of house construction assistance revised, varying from Rs. 2.5 lacs to Rs. 4.5 lacs

depending upon plot size; cost of flats and shops allotted to the entitled oustees at pre-

1989 construction cost, development cost not to be charged; State government allowed in

July’01 payment of cash grants to shop keepers of old Tehri Town ranging from Rs. 1 lakhs

to Rs. 3 lakhs depending on category of shop, subject to the handing over of possession.


6.5 REHABILITATION PACKAGE

Within the framework of the set principles, which guided the formation of Rehabilitation

Policy, an attractive and a liberal rehabilitation package was evolved, which has been

improved from time to time without changing its basic features.

a) Rural Package

2 acre, of developed irrigated land or half acre of developed irrigated land adjacent to

Municipal limits of Dehradun, Haridwar or Rishikesh cities or cash of Rs. 5 lacs in lieu

of allotment of land, as per their option.

Compensation for acquired land as per Land Acquisition Act plus solitium. Even if

acquired land is less than 2 acres, 2 acres of developed irrigated land is given, cost of

which to be adjusted from the amount of compensation payable in respect of acquired

land.

Cost of house property/trees acquired to be evaluated at the PWD/Forest/Horticulture

deptt. rates plus solitium. Further, ex-gratia equivalent to amount of depreciation,

subject to a maximum of Rs. 50,000/- is payable. Minimum compensation in case of

house is Rs. .00 lac.

Allotment of residential plot of 200 sq. m. to each family at nominal cost.

Cash grant for shifting is Rs. 5200/- and for seeds/fertilizers is Rs. 4960/-.

Additional incentive grant of Rs. 15,000/- payable to those who shift within 6 months

rom date of award of compensation or date of allotment of land, whichever is later,

after anding over their acquired property.

All the eligible additional family members for fully affected rural families attaining

the age of 21 years as on 19.07.90, and dependent parent (Mother/Father) would

receive x-gratia amount equivalent to 750 days of minimum agricultural wage per

member.


Cash grant ranging from Rs. 80,000/- to Rs. 1,20,000/- to each rural shop holder

depending upon the locations.

b) Urban Package

Land owners including Nazul land holders are given residential plot of various size

(60, 100, 150, 200, 250 and 300 sq.m.) in proportion to their holdings at very nominal

cost (ranging from Rs. 5 per sq. m. for plot up to 150 sq.m. to Rs. 150 per sq.m. for

plots of size 300 sq.m.) at locations as per choice, in addition to compensation of house

property as calculated in case of rural properties.

House construction assistance, as grant to the land owners at following rates less

compensation already paid;

a. • 60 –100 Sq.m. plot holders - Rs. 2.50 lacs

b. • 150-200 Sq.m. plot holders - Rs. 3.50 lacs

c. • 250-300 Sq.m. plot holders - Rs. 4.50 lacs

Ready to built houses/flats to entitled tenant who were residing prior to 06.06.1985,

on subsidized cost at pre-1989 rates.

Benap house owners who constructed house before 6.6.1985 are allotted either

house/flats or plots (if available).

Allotment of shop at cost in NTT/Dehradun/Rishikesh to those running shops at Old

Tehri own at pre-1989 rates.

Compensation for “Saj-Sajja”, for shopkeepers.

One shop to be allotted to shop owner who were not running shop(s) themselves in

O.T.T.

Cash grant of Rs. 3000/- to Rs. 4000/- for transportation of household effects and Rs.

1500/- to Rs. 2000/- for commercial goods. In addition, entitled families who hand over

their acquired properties and shift to new allotted sites within a period of 6 months from

the date of allotment of plot/flat, an incentives grant of Rs. 12000/- per family would be

paid.


One room flat to EWS families free of cost, upto a maximum of 100 families.

All additional eligible family members of entitled landowner families as per criteria

defined under rural package, get ex-gratia amount equivalent to 750 days of minimum

agricultural wage per member.

Cash option allowed in lieu of allotment of plots (Rs. 1.10 lac to Rs. 3.00 lacs), flat

(1.00 lac) and shop (Rs. 0.25 lac to Rs. 0.60 lac).

- The urban families are resettled at New Tehri Town (NTT) or at Rishikesh or

Dehradun, as per their option. The NTT, newly developed, is at a height of 1350 to

1850 m., overlooking the proposed lake, with a panoramic view of the Himalayas. It

has all the modern facilities for Education, Hospital, Financial Institutions, District

Administration offices, Markets, Bus Stand & places of worship etc.

6.6 INSTITUTIONAL MECHANISM

As per government decision, R&R woks were transferred to the U.P. State Government in

January 1999 for implementation, under control and supervision of Commissioner, Garhwal,

with funds to be provided by THDC. With the formation of Uttaranchal State, R&R was

being implemented by Uttaranchal/Uttarakhand State Government since January, 2001.

Subsequent to takeover, the Government of Uttaranchal have reconstituted the Co-ordination

Committee under the Chairmanship of Commissioner, Haridwar, Dehradun and other

Government and non-Government officials as members. The Co-ordination Committee has

now greater representation of the public representative; viz. MLA, Tehri; Chairman, Zila

Parishad, Tehri and Chairman, Nagar Palika Parishad, Tehri.


CHAPTER 7: FUTURE SCOPES

Estimation of permanent displacements of the Tehri dam in the Himalayas due to

future strong earthquakes-The objective is to estimate permanent displacements of

Tehri dam due to an earthquake of magnitude Mw = 8·5, the occurrence of which has a

high probability in the region, and for an earthquake of magnitude Mw = 7·0, for

which the dam has been currently designed. A two-dimensional finite element analysis

and five different semi-empirical and empirical methods, like, Seed and Makdisi’s

method, Newmark’s double integration method, Jansen’s method, Swaisgood’s method

and Bureau’s method have been utilized to study the probable dynamic behavior of the

dam and their results are compared to get a range of values within which, the

permanent displacement of the dam, is estimated to lie. The present study shows that

the predicted displacements due to an earthquake of magnitude Mw = 7·0 are

significant but not enough to compromise the safety of the dam. However, the

displacements predicted for an earthquake of magnitude Mw = 8·5 are quite high and

might cause rupture of filter zones. The maximum deformations (755 cm for Mw = 8·5

and 43 cm for Mw = 7·0) are predicted by Seed and Makdisi’s method while the

minimum deformations (14 cm for Mw = 8·5 and 2·5 cm for Mw = 7·0) are computed

by Jansen’s method.

7.1 Seismicity at Tehri dam

A number of large magnitude (Mw > 7) earthquakes have occurred along the

Himalayan mountain belt, four of which (1897 Assam earthquake (MS > 8·7), 1905

Kangra earthquake (MS > 8·6), 1934 Bihar earthquake (MS = 8·4) and 1950 Assam

earthquake (MS = 8·7)) had magnitude greater than 8 (Richter 1958).

The four great earthquakes in the past have ruptured only 200 to 450 km of the plate

boundary, leaving unruptured sections in between called seismic gaps. The unruptured

section of Himalaya between the rupture zones of Kangra &Bihar earthquakes is called

central Himalayan seismic gap. TheTehri dam is located within this seismic gap.

There has been considerable controversy concerning the seismic intensity to which

the Tehri dam may be subjected to as no great earthquake have occurred in this gap

region within the past 200 years .


The above researchers believe that the earthquakes in the past two centuries have not

been representative of infrequent great (Mw > 8) plate boundary event that could occur.

It is reasoned that recent earthquakes may have responded to different elastic driving

forces from those that drove the mega quakes of medieval times. It is suspected that an

alternate source of energy to cause a great earthquake exists in the form of elastic and

gravitational energy and is stored in flexure of the Indian plate, and is now sufficiently

mature to sustain a mega quake of Mw > 8 (Ambraseys & Jackson 2003; Ambraseys &

Bilham 2000).Here, the seismic behaviour of the Tehri dam has been studied for two

earthquake motions. The first one is an Mw = 7, PGA = 0·23 g earthquake for which

the dam has been designed (Thatte 1992). The second motion is for an Mw = 8·5, PGA

= 0·45 g hypothetical earthquake.

This second motion represents MCE of the region according to some experts and

initially recommended by THDC (1990) and High Level Committee of Experts (1990).

There are considerable controversies between the experts regarding the validity of these

motions. The proper way of coming up with a motion is to establish seismic sources

within 500 km and their maximum potential, and perform probabilistic seismic hazard

analysis.


7.2 Results-

The present study indicates that the displacements due to an earthquake of

magnitude(Mw) 7·0 are significant but not enough to compromise the safety of Tehri

dam.

The displacements due to a hypothetical earthquake of magnitudeMw = 8·5 are quite

large.

They might lead to a rupture in the existing 1m thick filter zones, resulting in

uncontrollable seepage.

The 2-D finite element analyses show that the maximum deformations

occur along the upper reaches of the upstream face of the dam while the

surface at the foundation level has almost negligible deformations.

For theMw = 7 earthquake, the maximum displacement is predicted by the

finite element method, while for the Mw = 8·5 earthquake, Seed and

Makdisi’s method predicts the maximum displacements.

All the simplified methods predict larger displacements on the downstream

face of the dam, but finite element method predicts almost two times larger

displacements for the upstream face of the dam.

Among the simplified methods, the maximum displacements are computed

by Seed and Makdisi’s method, while the minimum displacements are

obtained by Jansen’s method.

The large variation of the seismic displacements predicted by different

methods indicates scope for further research in this area and stresses on the

need for the instrumentation of the dams and verification of different

methods in predicting seismic displacements of dams.

The different dams coming up in the Himalayan region should be properly

instrumented to record ground motions, amplification of motions through the dam and

displacements of the dam, so that better understanding of the seismic behaviours of

large earth and rockfill dams can be achieved and proper mitigation measures can be

put in place before hand in case a disaster strikes.


CHAPTER 8: CONCLUSION

Tehri Dam is the biggest dam in Asia. It is situated on Bhagirathi River in

Uttarakhand, India. It is rock and earth filled massive water barrier. Tehri

Hydro Development Corporation (THDC) was formed in 1988 to manage the dam.

The dam started working in 2006. Tehri dam generates 1000 MW of hydroelectricity

along with an additional 1000 MW of pumped storage hydroelectricity (to be

completed in 2013).

The relocation of more than 100,000 people from the area has led to protracted legal

battles over resettlement rights, and ultimately resulted in the project's delayed

completion.

The Tehri Dam has been the object of active protestation by

environmental organizations and local people of the region. In addition to the

human rights concerns, the project has spurred concerns about the

environmental consequences of locating a large dam in the fragile

ecosystem of the Himalayan foothills.

There are further concerns regarding the dam's geological stability. The Tehri dam is

located in the Central Himalayan Seismic Gap, a major geologic fault zone.

This region was the site of a 6.8 magnitude earthquake in October 1991, with an

epicenter 500 km from the location of the dam.

Since Tehri dam is Rock and Earth filled dam, it is strong enough to withstand an

earthquake of 8.4 magnitude. Also like other dams, in case of breakage, the Tehri

dam will not collapse suddenly.


CHAPTER 9: LIST OF FIGURES

SR NO. FIG

NO.

DESCRIPTION PG NO.

1 1.1.1 Location of Tehri Dam 4

2 1.3.1 Tehri Dam 6

3 2.1.1 Tectonic Deformation of Dam 10

4 2.1.2 Crack identified in Tehri Dam 10

5 2.2.1 Cross section of Tehri Dam 11

6 2.3.1 Choice of Dam Site 12

7 4.1.1 Graph of Inflow & Outflow of Tehri Dam 20

8 4.1.2 Development of Pisciculture 21

9 5.1.1 L shaped crack on Tehri Dam 24

10 5.3.1 Reservoir level of Tehri Dam 26

11 5.5.1 Protest against construction of Tehri Dam 27


CHAPTER 10: REFERENCES

9.1 JOURNALS

“Effects of Tehri Dam”, S.C.Sharma, Former General Manager THDC Ltd

“Tehri Dam fact sheet”, IRN FACT SHEET, October 2002

“Cost and time over run in the construction of Tehri Dam project”, Dr. A.K.Dube,

THDC

“GIS and remote sensing-based study of the reservoir induced, land use in the

catchment of Tehri Dam in Garhwal, Himalaya”, Piyoosh Rautela, Rahul Rakshit,

V.K.Jha, Indian Institute of Remote Sensing (IIRS)

“Displacement and Development: the paradoxes of India’s Tehri dam”, Jason

Newton, University of Louisville.

“Impact of development activities on biodiversity – A case study of Tehri Dam”,

THDC

“Estimation of permanent displacements of the Tehri dam in the Himalayas due to

future strong earthquakes”, Aniruddha Sengupta, IIT-Kharagpur.

9.2 WEBSITES

www.caprarius-aquacom.blogspot.in

www.slideshare.net

www.euttaranchal.com

www.wikipedia.com

www.thdc.gov.in


environmental aspects tehri dam final

Engineering