NAVDANYA

Introduction

  The mighty Ganga catchments is the part of Hindu Kush Himalayan (HKH) region which sustains approximately more than 150 million people and affects the lives of more than three times that number in the plains and river basins below. Nearly 8,63,4000 million cubic meters of water is estimated to flow out of the HKH region annually (Gupta, 1983, Kawosa, 1998). 

The HKH has an area of 5,31,250 sq km, which is about 16.16% of India's total geographical area. It has been assessed that out of the total precipitation of around 400 m.ha.m. In India, the surface water availability is around 185 m.ha.m. In all twenty river basins (12 major & minor), out of this, only about 69 m.ha.m. can be put to beneficial use because of topographical and other constraints. 

The two largest Himalayan river, the Ganga and the Brahmaputra along with their tributaries, comprise the third largest land-water resource system in the world after the Amazon and the Cango-zaire group of rivers. Ganga basin extends from Gangotri to Ganga-Sagar (2525 km length) comprising of catchments area of 8,61,452 sq km.  

The Ganga sub basin on the other hand carries about 28% of the river flows having 26% geographical area of India. It is one of the most thickly populated and cultivated regions of the world. About 36% of the total Indian surface water lies in the Ganga sub-basin and another 6% in Brahamputra-basin.

The Bhagirathi is a major tributary of the Ganga River. Together with the Bhilangana it arises in the Chaukhamba Range of Uttarakhand, India.

The Bhagirathi is a turbulent Himalayan river originating at Gaumukh from the Gangotri glacier at an elevation of 7,756 m (25,446 ft), in Uttarakhand. It flows for about 180 km  before merging with the Alaknanda at an elevation of 465 m (1,526 ft) in the town of Devprayag. The river downstream from the holy confluence, Sangam, is known as the Ganges proper. Tehri dam lies at the confluence of the Bhagirathi and Bhilangana, near Tehri.

The word Bhagirathi literally means "caused by Bhagiratha", a mythical Sagar Dynasty prince who was instrumental in bringing the river Ganges from the heavens on to the earth, in order to release his 60,000 grand-uncles from a curse of the saint Kapila

Like the Ganges and most of its tributaries these rivers are sacred to Hindus, and its water is considered holy.

Physiography

Physiographically, the catchment area of Bhagirathi (upstream to Devprayag) falls in the mountainous Lesser and Higher Himalayan regions. The area exhibits a rugged topography with moderate to steep mountains, summit surfaces followed by escarpments, valleys and terraces. Entire terrain presents a picturesque landscape of steep to very steep slope intervening into narrow valley. Elevation of the study area ranges from 450 m to 7000 m above MSL. The area is criss-crossed by small nallahs and the tributaries. 

Geology and Seismicity

The rocks of lesser Himalayan zone of the area are dominated by the metasedimentaries while the higher Himalayan zone is characterized by high grade crystalline rocks with frequent basic and acidic intrusions. The granitic rocks (Gangotri granites) are present the upper most reaches of the Bhagirathi catchment.  The North Almora Thrust (NAT), exposed near Nalupani in Bhagirathi valley, divided the Tehri Phyllites (Chnadpur Formation) from the quartzites of Garhwal Group. Near sainj, the Main Central Thrust (MCT) is present which separates the rocks of Garhwal Group (quartzites, slates, carbonates etc.) from the rocks of Central Crystallines (gneisses and schists).  

As per seismic zoning map (IS 1893:2000) of India the present area falls in the zone IV and V. A number of structure elements like NAT, MCT and other transverse fault are present in this area. The occurrence of past earthquake is mainly clustered in the vicinity of the surface trace of MCT. Due to presence of a number of active faults and thrusts, the area is seismically active and construction of reservoir may also cause reservoir induced seismicity. 

Gangotri Temple

Eighteen kilometers downstream from Gaumukh, on the right bank of the Bhagirathi is the Gangotri Temple dedicated to the Goddess Ganga. It was built in the early 18th Century by a Gurkha commander, Amar Singh Thapa. It is one of the four sites in the Char Dham pilgrimage circuit.

Present Status of River Bhagirathi

Preliminary survey has been carried out through the course of the river Bhagirathi right from Devprayag to Gangotri. Main objective of this survey was to workout the current status of river Bhagirathi keeping in view that a number of Hydropower projects completed or under construction throughout the Bhagirathi River. In all three major hydroelectric power projects has been completed and two are under construction phase. In addition 3 mega projects are proposed one at Harshil, and 2 on Jad Ganga in Bhairav Ghati area (Table 1). On completion of on going and under construction project, there will be no more Bhagirathi river running right from Lohari to Koteshwar (near Tehri) covering an stretch of more than 125 Km. Besides to this, it would be a potential area of man made disaster in future. There are several evidences of adverse impacts (seen/observed) shortly within 1.5 years of completion of the Tehri dam.  

Major Bhagirathi Valley Hydro Power Projects at a glance: 

1.   Tehri Dam:

The project was approved in 1972 and construction was started from 1978. Towering to 260.5 m the main dam at Tehri is the 8^th tallest dam in the world. The dam's projected capabilities include a power generation capacity of 2400MW, irrigation stabilization of an area of 2.7 lakh hectare land and a supply of 270 million gallons of drinking water (per year) to industrialized cities in Delhi, Uttar Pradesh and Uttarakhand. 

Table 1: List of Hydropower projects, Constructed / under construction or proposed

Hydro-Electricity Projects on River Bhagirathi and Bhilangna

Hydro list - Uttarakhand (Above 25 MW schemes)
S. N.	Name of Project	Capacity (MW)	River (Tributary/ River/ River Basin)	District	Agency	Comment
1.	Maneri Bhali St-I	90	Bhagirathi	Uttarkashi	UHPC	Under operation
2.	Bhariron Ghati	60	Bhagirathi	Uttarkashi	UJVNL	under investigation
3.	Bharon Ghati- I	324	Bhagirathi	Uttarkashi	UJVNL	under investigation
4.	Bharon Ghati- II	240	Bhagirathi	uttarkashi	UJVNL	under investigation
5.	Bhela Tipri	100	Bhagirathi	Uttarkashi		under investigation
6.	Gangotri	70(55)	Bhagirathi	Uttarkashi		under operation
7.	Synachatti gangani	45	Bhagirathi	Uttarkashi	Pvt.	under investigation
8.	Lohari Nag Tharang	520	Bhagirathi	Uttarkashi		under investigation
9.	Loharinag-Pala	520 (600) ?	Bhagirathi	Uttarkashi	NTPC	Under Construction
10.	Maneri Bhali St- II	304	Bhagirathi	Uttarkashi	UJVNL	under Construction
11.	Pala Bhila Tipri	400	Bhagirathi	Uttarkashi		under investigation
12.	Pala-Maneri	416 (480)	Bhagirathi	Uttarkashi	UJVNL	Under Construction
13.	Hanumanchatti- Synachatti	33	Bhagirathi	Uttarkashi	Pvt.	yet to be developed
14.	Harsil Dam	350(210)	Bhagirathi	Uttarkashi		under investigation
15.	Koteswar	400	Bhagirathi	Tehri Garhwal	THDC	under Construction
16.	Tehri Pump Storage	1000	Bhagirathi	Tehri Garhwal	THDC	under Construction
17.	Tehri St- I	1000	Bhagirathi	Tehri Garhwal	THDC	under Operation
18.	Dhargoan-Jandarwa	29	Bhilangana	Tehri Garhwal		Yet to be developed
19.	Diulong-Sumangaon	26	Bhilangana	Tehri Garhwal		Yet to be developed
20.	Jamolna-Ghanshyali	44	Bhilangana	Tehri Garhwal		Yet to be developed
21.	Jadh Ganga	110(50)	Jadh Ganga	Uttarkashi	THDC	Under development
22.	Karmali	190(140)	Jadh Ganga	Uttarkashi	THDC	under development
23.	Nelang	190	Jadh Ganga	Uttarkashi		yet to be developed

 

Tehri hydropower project envisages 3 phase of power generation- Main Tehri Dam and Hydro Power Project (1000MW), Koteshwar Dam and HPP (400MW) and Tehri Pumped Storage Plant (1000MW). Tehri Hydroelectric plant has been in operation from 6^th July 2006. While Koteshwar power project is scheduled to be completed up to 2010 and Tehri Pump Storage Plant up to 2015. A sum of Rs. 8298.56 Cror has been spent so far on Tehri dam and HPP project till March 2008.

In Tehri Pumped Storage Plant, during the off peak hours, water will be pumped from Koteshwar Dam to Tehri Dam by utilizing 1712 MU/Year. This stored water will be utilized for generation of 1377 million units/year during the peak hours. Therefore, there will be no addition tKoteshwar Dam & Hydro Power Project (400MW) (78 m high) 22 km downstream of Tehri, is an integral part of Tehri Power Complex comprising of Tehri Dam & HPP (1000 MW), Tehri PSP ( 1000 MW) and Koteshwar HEP (400MW). The reservoir created by Koteshwar Dam will also function as lower (balancing) reservoir for Tehri PSP. Koteshwar Hydroelectric power project is a run off river scheme. Power house is under construction at 0.5 km downstream from main Dam. However, a huge slope failure occurred on 20.3.08, debris slides down towards the power house pit reflect the vulnerability of the existing slopes. 2 villages will come under submergence and 14 partially affected. 77 fully affected families rehabilitated and compensation is given to 292 partially affected families. o power to national grid on annual basis. In fact, this reversible pumping process will additionally consume 235 million units during off peak hours. So over all capacity of Tehri Dam Project is less than 1400 MW on an annual basis.

2. Maneri-Bhali Phase-I and Phase-II :

2a. Maneri Bhali Phase I have already been in operation from 1988. It is a run off river scheme, in which a small barrage was built at Maneri and water is diverted through a tunnel to powerhouse located 15 km downstream at Tiloth, Uttarkashi Town. Capacity of this powerhouse is 90 MW (45x45). Since past 10 years this Powerhouse has never generated electricity power to its full capacity. One of the reasons for low power generation has been repeated damage of turbine blade by the high-speed quartz mineral particles flowing with water.

 

2b. Manari-Bhali Phase II consists of a diversion barrage at Joshiyada-Gynsu Uttarkashi with its water level at 1404 m msl and a 304 MW capacity Powerhouse located 24 km downstream at Dharasu. This project has come in operation from January 2008. At present, this powerhouse is generating 102MW electricity only. A 16 km long tunnel has been constructed from Uttarkashi to Dharasu through left side of the river Bhagirathi. Whole river water is diverted to this tunnel for power generation at Dharasu. Water level is still low. 85 houses will drown if the reservoir in Uttarkashi if it stores water to its full capacity i.e. 1410m msl.  

3.  Loharinag- Pala Hydroelectric Power Project:

Loharinag-Pala is also a run off river Power-generating scheme with capacity 600 MW.  A Diverting Barrage is under construction at Loharinag (Songad). Bhagirathi river water will be diverted from Loharinag Barrage to 17 km downstream at Pala, where an underground Powerhouse is under construction. 12 km long tunnel passes through left side hills of river Bhagirathi. A river stretch of 16.2 km will be dried up when the Project would come in operation after 2015. 

4.  Pala- Maneri Power Project:

Water comes out from Pala Power House is to be diverted through a tunnel to Maneri, where a Powerhouse will be built below 30 m from the river bed. Power generation capacity of this Powerhouse will be 416 MW. Proposed site for the powerhouse locates just 100 m below the village Ongi. A 30 m long testing tunnel constructed below Ongi village has already collapsed as the whole hill is consist of old landslide debris and highly weathered, fractured and sheared rocks. A well-known Himalayan fracture zone, Munsiari Thrust also passes in vicinity of the proposed site. This Hydropower scheme will also render 12.5 km river stretch dry. 

Table: showing dried stretch of the river and length of tunnel, under construction / under operation or completed

Scorched Bhagirathi	River stretch to be dried or dry (Km)	Present status	Tunnel Length (km)	Present status