Posts Tagged 'River Valley Projects'

Western Ghats, India – The Forests

From the book  ”The Western Ghats” by Mohan Pai (2005).




“There was a time when meadow, grove
and stream,

The earth and every common sight
To me did seem Apparell’d in celestial light,
The glory and the freshness of a dream.
It is not now as it had been of yore;
Turn whereso’er I may,
By night or day, the things which I have
Seen I now can see no more.”

– William Wordsworth

As in many other tropical regions throughout the world, deforestation and forest degradation due to various factors such as extension of cultivated lands, grazing of livestock, extraction of forest products, commercial plantations, road and railway building, hydroelectric projects, atomic reactors and poaching continue unabated in the Western Ghats.

There have been various estimates and guesstimates about the loss of forest cover in the Western Ghats.
* A recent study (year 2,000) says that the Western Ghats, one of India’s most prestigious “biological hotspot” has lost one-fourth of its forest cover in the last 22 years. The study which estimated changes in forest cover between 1973 and 1995 in southern parts of the Western Ghats using satellite data reveals a loss of 25.6 percent in that period. The decrease in forest can be attributed primarily to increase in plantations and agricultural areas due to population growth with Kerala observing the most rapid changes.

The study also renews the debate that despite conservation measures adopted by various agencies, the rate of deforestation has accelerated in recent years. The data shows a whopping five fold increase in forest loss from the periods 1920-60 to 1960-90. The threat seems even bigger if one considers the fact that the study does not include forest degradation and habitat fragmentation that also eventually contribute to forest loss.

The southern stretch of the Western Ghats an area of approxi-mately 40,000 sq. kms, has experienced the most significant forest loss during 1973-95. There has been a loss of 2,729 sq. kms of forests with an annual deforestation rate of 1.16 percent.
(Study by ATREE, NRSA and University of Massachusetts, USA)

* According to U.N. Food and Agricultural Organization, the area alloted to plantations in India has been increasing at an average of 15 percent a year. At this rate, if all plantations were taken from existing forests – even the sparsely covered tracts – would be destroyed in less than a quarter century.

* An earlier report by TERI, New Delhi has made the following assessment:
Very little has been documented recently about the status of the forest cover in the Western Ghats, except that it seems to have declined between 1972 and 1985 at a rate paralleling that for India as a whole, which implies a loss of cover 2.4% annually. If we extrapolate from 1986 to 1989, this means a total loss of 34% from 1972 to 1989.

Still worse is the decline of the primary forest; the amount remaining seems to be no more than 8,000 sq. kms.
All but isolated pockets of original forest have been opened up by shifting, cultivation, allowing take-over by deciduous species and bamboo among other degenerate species.

* Another study reports (Menon and Bawa 1997): Nearly 40% of the natural vegetation in the Western Ghats disappeared between 1920 and 1990. Of these 76% were converted to open or cultivated lands and 16% to coffee plantations. The rest was due to conversion to tea plantations or hydroelectric reservoirs.

* Recent studies (Ramesh and Swaminathan 1999) indicate that in the Western Ghats of Karnataka, nearly 12% of the forests have been completely lost in the past two decades. During the same period in a region like Kodagu, coffee cultivation has increased by nearly 100% with a concomitant loss of 18% forest area.

* In the state of Kerala alone, in a period of 30 years, there has been a 47% decline in evergreen/semi-evergreen forests(Prasad 1998).
Less than a century ago 40 percent of India was forested. Large tracts of deciduous and tropical rainforests in the Western Ghats region were destroyed over the past century as the British expanded India’s railway network across the country. Then, between 1951 and 1976, some 15 percent of the nations’s land were converted to cropland and much of this came from natural forest.

Forests are strained by the increasing demand of their resources. As human and livestock population swell and forests shrink, the relationship between rural communities and forest has become increasingly precarious. Nearly 90 percent of the wood taken from the forests is used as fuel. And India’s forest provide fodder for some 100 million head of cattle that trample and denude under-growth as they graze.

Yet, India’s natural forests provide it with some extremely vital services: They protect topsoil from wind and water erosion, regulate temperatures, replenish aquifers, store genetic diversity, offer recreational relief and provide a number of products other than wood – including medicine and food.

Deforestation leads to several changes in the landscape. The degradation and fragmentation of forests, which generally precede deforestation, considerably affect the biodiversity of the region. In the Western Ghats, low elevation evergreen forests dominated by Dipterocarp constitute the most threatened habitat. Its continuum along the Western Ghats has been fragmented due to selective logging, increase in permanent settlements, and rubber plantations. Consequently, several typical low-elevation species have almost become extinct, several have become rare, and some species have taken refuge in the sacred groves.

One of the major forms of human interference to vegetation and flora in the Western Ghats is the building of dams. According to published sources, there could be hundreds including small and big dams, with Maharashtra alone having 631 dams(Nair and Daniel 1986).

Hill agro-systems in the Western Ghats are today dominated by estates chiefly of tea, coffee, rubber and monocultures of various tree species, including the oil palm that was introduced lately. Available estimate indicate that above an altitude of 1,500 m in the Western Ghats, there are 750 sq. km of tea plantations. A total ofnot less than 1,500 sq. km are under coffee and 825 sq. km under cardamom. It has also been highlighted that the Nilgiri district with a total area of 2,549 sq. km has around 1,000 sq. km under various forms of cultivation.

The impact of growing coffee in the Western Ghats has been studied to some extent. According to legend, the Arabica variety was introduced at the beginning of the 17th century by a Muslim pilgrim – Baba Budan, who brought seven coffee seeds from Yemen and planted them in his hermitage in Chickmagalur, Karnataka.

Coffee plantations were then introduced in Kodagu with large scale planting of coffee near Mercara. Growing in partial shade and the traditional system adopted by people have together favoured a greater diversity of native trees in the coffee dominated agro-systems of Kodagu.

Casurina plantations first appeared in Uttara Kannada district around 1868. Teak was first raised as monoculture in 1840. The first teak plantation in Kerala was established in Nilambur in 1844. Over the years, eucalyptus, cinchona, wattle, rubber, clove, cardamom, etc. have displaced extensive patches of natural forests throughout the Western Ghats.
Apart from introduction of commercially important plants, there have been invasions by a number of aggressive alien plant species during the past 200 years in the Western Ghats. Important among these are Lantana camara (var aculeata), Eupatorium odoratum, Mikania cordata, Parthenium hysterophorus, etc. Wattle (acacia) once introduced for the extraction of tannin in the higher hills is today a major threat to the Sholas and grasslands at these altitudes. The impact of these exotic plants has been subject of lot of debate.

Large number of ornamental plants of temperate origin have also run wild in the higher elevations of the Western Ghats. Hundreds of such species have been reported both from the Palni hills and from the Nilgiris. Human influences had an adverse impact on the diversity of flowering plants in humid forests of the Western Ghats. In the Uttara Kannada district lack of coppicing ability in conjunction with their use in the wood/matchwood industry has led to disappearance of several evergreen species.

With villagers concentrating on harvest of trees in the height class of 4 – 8 m as poles and commercial interests mostly extracting trees above 16m height, there was a reduction of around 45% in all height classes between the sites of low and high level disturbance.

Unique landscapes such as Myristica swamps gave way to cultivation of rice. Along with the swamps many species of the swamp trees disappeared locally. Selective logging in the Western Ghats has had differential influence on biodiversity. When evergreen forests are thus disturbed, the woody plant species diversity has shown a gradual decline. This has been accompanied by the selective loss of certain species of greater economic value and an overall reduction in forest biomass. Other organisms have responded to human disturbance of evergreen forests rather differently. Selective logging (consequently lower tree and canopy density) has locally increased the diversity of butterflies, lizards and birds in the Western Ghats.

Top Soil & Siltation

Deforestation leads to a very sizeable loss of the top soil. It is only the forests on the slopes that prevent the run-off which takes place after heavy rains and allow water to percolate into the earth. Loss of tree cover means the top soil that is held in place by the roots of the trees becomes loose and the run-offs carry the top soil to the bottom of the river causing siltation.

Where the top soil is lost, there can be no vegetation; most deserts for instance, are what they are because the wind has blown away the top soil, and no trees can grow there any more. We cannot really ‘create’ top soil, for top soil is the product of innumerable layers of leaf litter and dead vegetable matter which disintegrate and mix with the earth. It can take anything from 500 to 1,000 years to build up one inch of new top soil. No amount of money can buy new soil. 

River Bhadra at Kalasa, Karnataka – Pic by Mohan Pai

Most loose soil from the hill slopes gets to a riverbed very fast, for in a heavy shower it travels down with the rain water or run-offs and settles down at the bottom of the riverbed, raising by a little bit, the level of the riverbed. This rising of the river bottom is called siltation and it is this which is the root cause of the floods which now we face every year. Floods are only one facet of the damage.

River Pravara near Wilson Dam, Maharashtra – Pic by Mohan Pai.

As the river bears with it its load of silt and mud out to the sea, harbours too are silted up, making it necessary to continuously carry out expensive dredging opera-tions.

The cycle of losing valuable soil, the siltation of riverbeds and consequent flooding has a strong adverse impact on the environment of the region. What is worse is that we are not only losing the invaluable soil, but large quantities of underground water as well.

River Valley Projects

The hydel potential especially of the west-flowing rivers is being utilised round the year by impounding seasonal waters behind high rise dams situated at strategic locations. To utilise the available head, water is channeled through penstocks to turbines in power houses. Penstocks in earlier projects as at Sharavathy in Karnataka and Khopoli in Maharashtra were on the surface.

Wilson Dam, Bhandardara, Maharashtra – Pic by Mohan Pai

In recent years penstocks have been laid in steep tunnels bored into rocky mountains. Idduki in Kerala and Nagjahri on the Kali have covered penstocks. The power houses also have gone underground as at Idduki and Varahi where they are within the mountain. Hydel generation is considered to be clean and relatively cheap. The environmental costs of hydel projects are, however, high though not easily quantifiable. The environmental issues of hydel projects are site specific but many are common. The following is a list of some common issues:

1. Submersion of large scale vegetation by the reservoir.
2. Degradation of forests due to quarries, roads, power lines and housing colonies.
3. Disturbance to wildlife during construction and change of the habitat after the construction.
4. Siltation of the reservoirs due to inadequate catchment area management.
5. Possibility of reservoir induced seismicity.
6. Cumulative impact of a series of dams and reservoirs in close proximity.
7. Displacement of people and lack of proper rehabilitation.
8. Impact on riparian communities when the pattern of river f low is changed or the water of one river basin is diverted to another basin.
9. Increase in salinity due to ingress of sea water, especially when water of a river is diverted to another basin.
10. Cumulative impact of all developmental activities in a particular region of the Western Ghats.

Submersion of Vegetation

The water impounded by the high dams generally submerge large tracts of evergreen forests of the western valleys. Linganamakki reservoir of the Sharavathy hydel project in Karnataka submerged 326.3 sq. km, mostly covered by luxuriant forests.

Harangi Dam Reservoir, Kodagu

 In order to increase the quantity of stored water, auxiliary dams were constructed. The waters from Savehakkalu and Chakra further reduced the forest cover in Shimoga district of Karnataka. The Periyar basin in the High Ranges of Kerala has a series of 12 large dams which directly or indirectly resulted in destruction of about 4000 sq. km of rainforests and grasslands. Kali river with 6 major dams has submerged about 32,000 acres of prime forests in Uttara Kannada district. As hydel projects are being multiplied more forests are being lost. The compensatory afforestation programmes in arid areas do not compensate for the loss of rich evergreen and moist deciduous forests of the Western Ghats.

Colonies, quarries, roads and power lines

At peak construction activities, the work force at Sharavathy was around 50,000. Housing colonies were set up after denuding the surrounding hills. During the Kali stage, the township of Ambikanagar in Uttara Kannada was located in an area that still then was covered by dense forests. Before handing over the area to Karnataka Power Corporation, the forest department removed all the trees and handed over a totally denuded area. A similar denudation occurred at Ramanagara, the rehabilitation area for the Supa reservoir oustees .

Supa Reservoir on Kali Nadi, Karnataka – Pic by Mohan Pai

Degradation of wildlife habitats

The Western Ghats have a rich fauna. Herds of elephants, gaur and deer, flock of birds, many species of reptiles and amphibians, to mention a few, have inhabited these forests. The blasting of rocks, the rumble of heavy machinery, the incursion by humans have greatly reduced the fauna of the Ghats. These activities have also fragmented the forests to a large extent.
The change in river flow patterns so essential to spawning and migration of fishes has resulted in a drastic reduction of aquatic fauna. The lack of fish ladders in most dams confines fishes to particular areas and prevents normal movements. Studies have shown a marked reduction in aquatic fauna.

Siltation of reservoirs

The slopes of the Western Ghats are steep. The rainfall is heavy during the monsoon. Once the forest cover is lost and the grasslands are disturbed, run-off and soil erosion is high. Other activities in the catchment area increase the silt load. The Kali river valley schemes afford matter for a case study. In addition to 6 large dams, this area has nine active mining operations with scarcely any measure for controlling mine run-off and soil erosion from tailing dumps. Each of the mines contributes to the silt-load of the river. The water holding capacity of each reservoir is being reduced by this siltation.
Reservoir induced seismicity
Seepage and pressure built up by a large mass of water are known to induce seismicity. In order to monitor seismic movements and dam vibrations new techniques are being adopted. The double arch dam at Idduki has a number of sensors embedded in it. Most dams in the Western Ghats do not have such monitoring devices. Reservoir induced tremors and earthquakes in the Koyna region were felt several hundred km away from its epicentre. Had the dam collapsed, several downstream towns would have been washed away.

Cumulative impact

The environmental issues relating to hydel projects become more pronounced when a river has a series of dams or, when several basins in close proximity are taken up for power generation. The Sharavathy and Kali basins have a concentration of hydel projects. The series of dams and reservoirs alter the riparian ecology and biodiversity. The biota of a natural river bank cannot survive on the artificial shores of a reservoir. The cumulative impact of several projects has to be examined. As indicated earlier, the Sharavathy with its many dams and reservoirs destroyed extensive forests in Shimoga district. The Kali project has ruined a rich game sanctuary. The Koyna project resulted in seismic disturbances.


Mattupetty Dam Reservoir , Kerala – Pic by Mohan Pai

Silent Valley in the Western Ghats is a concrete example of abandoning the project due to prudence. The plans to submerge the Silent Valley caused a lot of agitation among conservationists. The scheme was to build a dam 390 ft high and 720 ft wide which would be used for the generation of 120 MW of hydroelectric power and would irrigate 5,000 acres of land. In this instance the conservationists were quite sure that the amount of damage that would be done by constructing the dam would be out of proportion to the advantages gained. The balance sheet was simple. The evergreen rain forests of the Silent Valley which would be submerged by the dam, was the kind which has evolved over thousands of years; there were few comparable areas of such forest left in India, and, once it went, it would mean that we had lost not only the forest itself, but hundreds of plant species which had not yet been studied. Fortunately the pressure from conservationists resulted in project being dropped. However, there is a recent move by the Government of Kerala to reopen the Silent Valley Project with a dam on Kunthipuza river.

Displacement and resettlement

Several studies have been made on displacement of people due to land acquisition and land submersion. The hydel reservoirs in the Western Ghats have displaced many thousand of people especially tribals and agriculturists. For example, the Kali project in Karnataka displaced 1,665 families, The Savehakkalu and Chakra projects displaced 227 families, the Varahi 1,361 families.

The trauma of displacement is made more painful by the inadequacy of the legal and financial provisions. Especially the displaced tribals go without any compensation. The socio-cultural environment of displaced communities is shattered. Their means of livelihood are undermined. Skills have to be learned once again as they shift from non-market economy to a competitive market based economy.

The responsibility of resettling displaced people is that of various departments of the State and Central Governments. Legislation to ensure justice to the displaced is weak and outmoded. There is a strong feeling among the displaced that “Peter is being robbed to pay Paul”.

Impact on riparian communities by changes in river flow

At the peak of the S-W Monsoon, the crest gates of the dams are opened to release excess water. The sudden release have affected the people living along the river banks. The situation can be so critical that the army has been called upon to rescue the marooned people. Sometimes the hydel projects are so designed that water from one river basin is diverted to another.
For example the double arched dam sealed the Periyar. The water in the reservoir is being diverted to the power house at Moolamattom. The tail race from the power house meets the Muvattapuzha river, leaving the Periyar with highly reduced flow. This has adversely affected the communities along the Periyar banks. A similar situation has resulted by the westward diversion of the waters of the eastward flowing Koyna river.

Increase in salinity due to ingress of sea waters

When there is reduction in flow of a river due to diversion of its water, the river in its lower reaches is not sufficiently flushed by the monsoon rains. Thus there is acute scarcity of fresh water at Ernakulam because of ingress of sea water after the construction of Idukki dam.

Cumulative impact of developmental activities

There are different activities going on simultaneously in the Western Ghats. Besides the hydel projects, irrigation projects are also implemented. Surface mining is taken up both within the forest and outside them. The controversial Kaiga Nuclear Power station, the only nuclear plant in a forest in the world is located at Kadri in the Kali river basin. There are traditional activities of forestry, agri-culture, horticulture. Plantations of coffee, tea, cardamom, pepper, rubber and ginger are being expanded. The cumulative effect of all these activities seriously threatens the ecosystems of the Western Ghats and undermines the resource base in this mountain range.

Irrigation Projects

In order to conserve seasonal waters of the east-flowing rivers, innumerable dams both big and small have been constructed in the Western Ghats and in the peninsular India. These are classified as large, medium and small irrigation projects. Only the large and medium irrigation works are being considered here. The Western Ghats merge with the Deccan plateau on the eastern side. They descend gradually from the ridge forming shallow valleys. Where the rivers flow through a narrow neck formed by the hills, dams are constructed to impound the water which is then conveyed over long distances by canals. The submergence of these valleys is of great consequence.

The moist deciduous forests are rich in timber species like rose-wood, teak, venteak. The fauna is varied and abundant. Many of the wildlife sanctuaries are located here. Plantations of coffee and tea, gardens of areca and pepper, orchards with a variety of fruit trees thrive well in these valleys. Flourishing agricultural communities have occupied the area and harvested cereals and pulses. Several studies have been carried out on the impact of these irrigation dams in the Western Ghat. Some of the environmental issues associated with these dams are common to hydel projects. Some are specific to the projects in the shallow valleys in the rain shadow area of the Ghats.

Deforestation and the Global Carbon Cycle

Carbon dioxide ( CO2) is the major gas involved in the greenhouse effect, which causes global warming. All the things that produce CO2 (like car burning gas) and the things that consume Co2 (growing plants) are involved in the “global carbon cycle”.

Tropical forests hold an immense amount of carbon, which joins with oxygen to form CO2. The plants and soil of tropical forests hold 460-575 billion metric tons of carbon worldwide. Each acre of tropical forest stores about 180 metric tons of carbon.

Deforestation increases the amount of CO2 and other trace gases in the atmosphere. When a forest is cut and replaced by cropland and pastures, the carbon that was stored in the tree trunks (wood is about 50% carbon) joins with oxygen and is released into the atmosphere as CO2.

The loss of forests has a great effect on the global carbon cycle. From 1850 to 1990, deforestation worldwide (including that in the United States) released 122 billion metric tons of carbon into the atmosphere, with the current rate being 1.6 billion metric tons per year. In comparison all the fossil fuels (coal, oil and gas) burned during a year release about 6 billion tons per year.

Releasing CO2 into the atmosphere increases the greenhouse effect, and may raise global temperature. The role of fossil fuels burned by cars and industry is well known, but tropical deforestation releases about 25% of the amount released by fossil fuel burning. Tropical deforestation, therefore, contributes a significant part of the increasing CO2 in the atmosphere.

Mahadayi/Mandovi River Valley, India – Part I


This document covers a very important and ecologically vital geographical area which is rich in biodiversity – the Mahadayi/Mandovi River Valley in the central Western Ghats. Most of the forests in the Western Ghats have already disappeared due to population pressure and ‘development’ schemes that do not consider the long term consequences but merely look at the short term gains. And now it is the turn of this pristine valley to fall under the axe.

River Madei at Sonal Village, Sattari, Goa – Pic by Mohan Pai

This is mainly a pictorial documentation which attempts to bring out the natural wealth of this valley – its streams and waterfalls, its forests and wildlife, its people and the millennia old civilization and settlements on the banks of the river Mandovi in Goa all of which stand to be decimated due to Karnataka’s river valley project which proposes to divert a sizeable quantum of water from the Mahadayi to the Malaprabha river in Belgaum district of Karnataka. But the project is far more ambitious. It includes building as many as 11 dams on the Mahadayi and its tributaries in a small area of 50 sq km along with hydroelectric projects.

The project will submerge a vast area of thousands of acres; most of it will be thick forested area. The tribals living in the area will be displaced. Once these forests are destroyed there will be a drastic change in the ecology of the valley ruining its forests, wildlife and all its natural wealth.

Gavali Tribals of Chapoli – Mother & Child – Pic by Srihari Kugaji

The core catchment area of the Mahadayi lies in the heavy rainfall, thickly forested, approximately 200 sq km of mountain topography of Khanapur taluka, barely 10 km upstream of Valpoi in Goa, where Karnataka’s diversion and hydroelectric dams are to come up.

In my earlier book “The Western Ghats” , I had attempted to bring out the ecological damage that is being continually inflicted on the Sahyadris. The biggest ecological damage inflicted upon the Western Ghats is deforestation. The Western Ghats eco-region with an area of about 1,59,000 sq. km has been classified as a global ‘Hotspot’. This means that this is an area which is rich in endemic plant species and which has already lost more than 70% of its original habitat and is under severe threat due to human pressure.

The Mahadayi is a comparatively minor stream that arises in the Western Ghats and the river valley is a large pocket of dense, pristine monsoon forests, one of the richest reservoirs of biodiversity in the world that reflects complexity in plant, animal, bird life and is home to some rare endangered species of bats.
Mahadayi river valley is in the news because of the inter-state water sharing dispute between Karnataka and Goa. The Mahadayi Valley has been facing many threats. Illegal felling of trees and illegal mining has been going on for decades. Large scale plantation of exotic species (acasia & mangium) has also been damaging the ecology of the area.

With water diversion and hydroelectric projects, the Mandovi river, Goa’s life-line, faces imminent threat of choking because of the reduction in water flow, siltation and disruption of its ecology due to change in its profile – perhaps being even reduced to a trickle in the summer months and possibility of seismic disturbances.

The main threat that is now looming over the valley is the Karnataka Government’s plans to divert a large quantum of water from the Mahadayi river and its tributaries to the Malaprabha river basin to help the acute water scarcity faced by the region in the Malaprabha basin. But as long as the exploitation of water resources continues in the Malaprabha region, no matter how much water and from where it is diverted, the Malaprabha valley is likely to face the same situation in the near future.

But the project is far more ambitious. It includes building as many as 11 dams on the Mahadayi and its tributaries in this small area along with hydroelectric projects. The project appears to aim at impounding a large portion of waters from the Mahadayi and its tributaries that flows into Goa, which will mean that Karnataka retains and controls all the dams and the Mahadayi waters.

It is estimated that this project will submerge a vast area amounting to about 3,000 hectares; most of it will be the thick forested area on Karnataka side of the valley. Once these forest are destroyed there will be a drastic change in the ecology of the valley reducing the rainfall, ruining its forests, wildlife, and all its natural wealth.

Fungal diversity – Pic by Srihari Kugaji

The core catchment area of the Mahadayi lies in the heavy rainfall (3800mm-5700 mm per annum) thickly forested, approximately 200 sq. km of mountain topography of Khanapur taluka barely 10 km. upstream of Valpoi in Goa. A very large quantity of water that flows down the Mandovi all the year round originates in the streams and rivulets around Kankumbi, Jamboti, Talewadi, Gavali and Hemadga villages where Karnataka’s diversion and hydroelectric dams are to come up. The Mandovi river, Goa’s lifeline, faces imminent threat of choking because of the reduction in water flow, siltation and disruption of its ecology due to change in its profile – perhaps being even reduced to a trickle in the summer months.

Every variation in the Mahadayi water level will be crucial for Goa’s ecology, forests, wildlife, agriculture, drinking water, fishing and transportation.

Whither the Sahyadris ?

The Sahyadris or the Western Ghats is a major mountain range of the world that runs 1,600 km N-S forming the “girdle of the earth” and is the most important feature of the landscape of the southern peninsula of India. It has been classified as a “Global Biodiversity Hotspot” which is under constant threat due to human pressure.

It’s a precious gift of the Nature – priceless because the well-being of the entire southern peninsula hinges on the ecological stability of these mountains. And yet, there is a mindless exploitation and wanton destruction. The rate of forest destruction in the Sahyadris continues at a staggering rate. Tragically for the country and the region, most of the forest cover in the Western Ghats has disappeared.

The Western Ghats are remarkable headwaters and the main watershed for the southern peninsula serving six states; sustained by the heavy seasonal rainfall from the south-west monsoon, from which all the major and many smaller rivers of the southern peninsula originate and flow east or west emptying into the coastal waters. The real merit of the Western Ghats forests in terms of their watershed value is incalculable. These forests once destroyed are gone forever. No amount of scientific knowledge or investment in afforestation can get us back our rivers.

The Western Ghats eco-region covers an area of about 1,59,000 sq km and is shared by six states viz., Gujarat, Maharashtra, Goa, Karnataka, Tamil Nadu and Kerala. Around 40 districts fall within the limits of this region. Population density is lowest in the Dangs in Gujarat – 106/km2 and highest in Alapuzha in Kerala – 1489/km2. Tribal population classified as tribals (ST) are highest in Gujarat (14.9%), followed by Maharashtra (9.27%) and least in Tamil Nadu (1%) and Kerala (1.1%).

There are 58 protected areas – 13 National Parks and 45 Wildlife Sanctuaries. The total area of 14,140.36 km2 that is thus protected amounts to only 8.8% of the eco-region.

Of the remaining few pockets of dense pristine, evergreen forests, the Mahadayi River Valley located in the northern Karnataka and Goa now faces the Democles’s Sword in the shape of the proposed water diversion and hydroelectric schemes in Karnataka that will submerge an area of about 3,000 hactares, most of which will be the dense evergreen forests.

The Mahadyi River Valley one of the last “Wildernesses” with dense evergreen forests, abundant wildlife, beautiful streams and waterfalls covers an area of 750 sq km and is comparable to the Silent Valley(89.5 sq. km.) in Kerala in its wealth of biodiversity but much larger in area.


Pic by Amrut Singh

(The King Cobra – Ophiophagus hannah is the longest venomous snake in the world also called the Hamadryad which grows up to a length of 18 ft and is one of the most enigmatic creatures found in the Western Ghats. It is a snake that is highly feared and deeply respected and the Mahadayi Valley is a prime habitat of this snake. At Caranzol in Sattari taluka there are some well-identified habitats of the King Cobra.)

Global Biodiversity Hotspots

Norman Myers, a conservation biologist, in 1988 first identified ten tropical forest ‘hotspots’ characterised by exceptional levels of plant endemism and by serious levels of habitat loss. In 1990, Myers added another 8 spots to his list. Conservation International adopted Myer’s hotspots as its institutional blue print in 1989, and in1996.

To qualify as a hotspot, a region must meet two strict criteria: it must contain at least 1,500 species of vascular plants as endemic and it has to have lost at least 70% of its original habitat. These are the areas which are under constant threat due to human pressure. In the 1999 analysis, in all 25 hotspots were identified. A second major analysis was undertaken and the number or global hotspots stood at 34 in 2005.

Overall, the 34 hotspots once covered 15.7% of the Earth’s land surface. In all 86% of the hotspots’ habitat has already been destroyed. The intact remnants of the hotspots now cover only 2.3% of the Earth’s land surface. Over 50% of the world’s plant species and 42% of all terrestrial vertebrate species are endemic to these 34 biodiversity hotspots.

Among the 34 Global hotspots of the world, two have been identified in India; the Eastern Himalayas and the Western Ghats .

Of India’s 15,000 plant species with 5,000 endemics (33%), 4050 plants with 1,600 endemic species are found in a 17,000 sq km strip of forests along the seaward side of the Western Ghats in Maharashtra, Goa, Karnataka and Kerala. The Western Ghats Eco-region has 938 vertebrates (36% endemic), 330 species of butterflies (11% endemic) and other lower plants and animals. Endemism is highest in amphibians (78%) and lowest in birds (4%). As per the classification of ‘hotspot’, the Western Ghats have lost more than 70% of its original habitat and forest cover. Many species have already become extinct or have become endangered and on the verge of extinction.

Glassy Tiger (Parantica aglea Stoll) Wingspan: 70-85 mm – Pic by Mohan Pai

The Mahadayi river valley is rich in insects diversity and butterflies are perhaps the most colourful and conspicuous of insects. The butterflies in the valley include ‘Southern Birdwing’ , the largest of southern Indian butterflies with a wingspan of 140-190 mm and the smallest of the butterflies ‘Grass Jewel’ with a wingspan of 15-22 mm

Mahadayi – “the Great Mother Goddess”

Ancient carved image of ‘Gajalakshmi’ at Caranzol – Pic by Mohan Pai

In India, its mountains, rivers , trees and animals are honoured and revered more than any other nation in the world, seeing these objects as manifest divine creations. The rivers, especially are considered manifest forms of divine female powers that have descended from heaven. “Ganga Jal” is revered with implicit faith as an essential element of one’s salvation. “Ganga” in popular speech is used to describe any river since she is the Bhagirathi brought down to earth and could be received only by Lord Shiva and she is the mistress of all as in her they must all unite.


 Quite a number of ancient stone sculptures, representing the River Goddess have been discovered in and around the banks of the Mahadayi river both in Khanapur, Karnataka and in Goa indicating the existence of a dominating cult of the River Goddess in the area.
The Boat Goddess sculptures depict the Goddess standing in a boat, holding a dagger in her right hand and a bowl in her left hand. She is known by various names such as ‘Naukayana’ Devi (Boat Goddess), ‘Ashtabhuja’ (eight hands) Durga, ‘Mahishasuramardini’, etc.
All these sculptures probably belong to Kadamba period (12th or 13th Century AD). These sculptures have been found mostly in Sattari taluka at Nadve, Savarde, Dhamashe, Shel-Melawalli, Dhada and Guleli.

Mahadayi near Krishnapur – Pic by Srihari Kygaji

The Mahadayi river originates in Khanapur taluka of Belgaum district of Karnataka on the eastern slopes of the Sahyadris and flows west meeting the Arabian Sea near Panaji in Goa. But for the people of Khanapur and the eastern taluka of Sattari in Goa, She is the MAHADAYI – ”the Great Mother Goddess” as the name itself implies. The number of ancient carved images found scattered at Amgaon and Parvada in Khanapur Taluka and Sattari taluka of Goa at Caranzol, Savarde, Kodal, Rivem, Irvem, etc. represents the cult of the Mother Goddess worship on the banks of the Madei. The river Mahadayi becomes Madei in Sattari taluka of Goa and after the river Khandepar joins it at Bembol the river is called the Mandovi.

Like most monsoon-fed rivers, the Mahadayi also undergoes bewildering transformation during her seasons; slack, limpid pools of winter, partially dry beds of summer turning to fearsome torrents during the monsoons, submerging everything in its way and awesome in her destructive potential.

Damning the Rivers

When we dam the rivers, we literally damn them to an unnatural existence.
Patrick MacCully in his book “Silenced Rivers – The Ecology & Politics of Large Dams” says that the era of dams and damming rivers the world over is over (quite simply there are fewer and fewer rivers left to dam). In the United States now they are decommissioning dams and trying to restore their rivers to there original status, which is quite an uphill task. About 40 dams have been removed since 1999 when the breaching of Edwards Dam on Maine’s Kennebec river captured national attention. Another milestone was reached in October 2001, when conservationists celebrated the completion of a series of dam removals that restored 115 miles of the Wisconsin’s Baraboo river, the longest stretch of river ever returned to free flowing condition in America.

But in India state after state is hell-bent on damming the rivers either for irrigation or power orfor both under the guise of “development”. Past experience has proved that these so called“development” projects end up with far more incalculable, irreparable ecological damage. Thousands and thousands of sq. kilometers of forests have been submerged. In fact most ofthe forests in the Western Ghats have gone. The destruction of forests has very adverse effecton watersheds and catchment areas; thousands of families have been displaced, most of the time without proper resettlement; the wildlife and the flora of the area is completelywiped out; all this without any benefits to the local population. But what these projects in essence do is to destroy the ecology of the dammed rivers that have provided life-giving support for centuries to a wilderness of flora and fauna and civilisations on their banks. The ecology of the rivers is severely affected by dams, their waters running dry and they are reduced to a gutter status with only skeletal remains.

After these mega-investment, quite a number of dams get silted with not enough storage either for irrigation or to produce power. And there is also a danger of seismic disturbances to the areas.

Anjunem Dam on Costi river, Goa. – Pic by Mohan Pai

Hydropower projects & greenhouse gas emission

Latest scientific estimates show that large dams in India ar responsible for about a fifth of India’s total global warming impact. The study titled, “Methane emission from Indian Large Dams” estimates the total generation of methane from India’s reservoirs could be around 45.8 million ton, more than the share of any other country in the world. These gases are produced by the rotting of the vegetation and soils flooded by reservoirs, and of the organic matter (plants, plankton, algae, etc. Large dams have been known to be emitters of greenhouse gases like methane, carbon dioxide and nitrous oxide for over a decade now.
Indian hydropower projects are already known for their serious social and environmental impact on the communities and the environment. The fact that these projects also emit global warming gases in such significant proportion should further destroy the myth.


The Water Disputes

The water endowed upper riparian States consider the water in their rivers as their property. As interstate rivers are not located entirely within a State but only flow through its territories, no State can lay exclusive use of such waters and/or deprive other States of their just share.

However, these States who zealously safeguard their autonomous status and rights forget or deliberately ignore their obligations to cooperate with each other while practising federalism. Because of this situation, many Chief Ministers of water deficit States have been forced to demand nationalisation of rivers.

The ongoing disputes are several- the Kaveri waters, the Krishna Basin, Indus Basin, Mahanadi Basin, the Indravati waters and now the Mahadayi waters. The Water disputes between the States are getting murkier due to the despicable actions of political opportunists. Vote bank politics has succeeded in dividing the culturally united dwellers of these basins into upper and lower riparian blocks to fight each other for their water rights. These people who are steeply bound by traditions for generations, who have been sharing the bounties of the river happily and its distress with concern for each other are now at each others throat fighting for their share of the same life-giving waters.

Karnataka’s unilateral decision to go ahead with the Mahadayi River Valley projects is now amounting to a very real threat. Karnataka is fully aware that the Mahadayi/Mandovi is a lifeline river for Goa and yet it is hell bent on diverting the Mahadayi waters into the Malaprabha basin. Most of the water from Karnataka’s Navilutirtha reservoir on Malaprabha goes for irrigation of water guzzling crops like sugarcane in its upper reaches creating a drought-like situation in its lower reaches. This has created a man-made water crisis in Hubli-Dharwad area. If Karnataka cuts a fraction of water released for irrigation, there will be no drinking water shortage for Hubli-Dharwad.

Goa State is a part of the narrow Konkan coastal strip on the western side of the Western Ghats (15 47’ 59’ and 14 53’ 47” North latitude and 74 20’13” and 73 40’33” East longitude. The entire eastern part of Goa State is flanked by the western slopes of the Sahyadris that extends in the form of an arc with a length of 125 km N/S and covers an area of about 750 sq km. The rainfall remains relatively high over this tract in view of the comparatively low elevation. The Sahyadri crestline zone borders Goa and Karnataka and most of the streams flowing into Goa, originate just across the border in Karnataka.

Vajra Sakhala Waterfalls in Chorla GhatPic by Mohan Pai

The Mahadayi/Mandovi is the most important west flowing river of Goa. The river arises in the Western Ghats of Karnataka at Degaon in Khanapur taluka at an elevation of 940 m with a total length of 87 km(35 km in Karnataka and 52 km in Goa). The river and its tributaries drain about 2,032 sq km area out of which 375 sq km in Karnataka, 77 sq km in Maharashtra and 1,580 sq km in Goa. The Mahadayi/Mandovi river basin in Goa occupies 43% of the total area of the State and this explains why maintaining the ecology of the river is so vital to this small State.


Emerald-green fields on the banks of the Madei – a village near Honda, Sattari Taluka, Goa-Pic by Mohan Pai

The ecology of the Mahadayi basin is already very fragile on account of large scale deforestation and illegal mining in Khanapur taluka. Karnataka now proposes to intercept the yield from about 258 sq km which is the core catchment area of the Mahadayi. The massive diversion of the Mahadayi water from this area will see a quantum jump in the silt flowing down from the denuded mountain ranges from across the border and will result in water flow being reduced to a trickle. For Goa, the fresh water flows from the core catchment area that lies in the heavy rainfall, thickly forested area of about 200 sq. km. of mountain topography of Khanapur taluka barely 10 km upstream of Valpoi in Goa. A very large quantity of water that flows down the Mandovi all the year round originates in the streams and rivulets that spring around Kankumbi, Jamboti, Talewadi, Gavali and Hemadga villages.

Goa has been at the mercy of its two larger and powerful neighbours and bordering states of Maharashtra to the north and Karnataka to the east and the south. Most of Goa’s major streams – Tiracol, Chapora, Mandovi, Surla, Ragoda, Khandepar and Galgibag originate just across the border in the Western Ghats of either Maharahtra or Karnataka. For this reason Goa is an extremely vulnerable state when its bigger neighbours draw ambitious plans to create large storages or divert waters close to the sources of rivers flowing into Goa.

The Mahadayi/Mandovi river valley is one of the few surviving pockets of the “Last Wilderness” in the world and the main watershed for Goa’s rivers. It’s a pity that instead of saving and protecting it, it has now come under the axe for the sake of “development”!

Mahadayi/Mandovi River Valley, India – Part II


Threats to the Valley

Location of the Valley

The Mahadayi River Valley is one of the few remaining areas of wilderness in the Sahyadris and like the threats to these remaining wildernesses all over the world, this piece of wilderness is also facing several threats due to human pressure.

Mahadayi River before Vajra Poha Waterfalls – Pic by Srihari Kugaji

The main threats are as follows:


Many forest patches in the valley are privately owned (malki lands). The owners of these lands are a law unto themselves. While the Forest Act provisions are also applicable to private forest lands there is nothing much that can be done to prevent the owners from felling trees. Many malki lands have been denuded of tree covers and converted to food and cash crops. There are instances of valuable forest lands being sold to unscrupulous elements. There was a move to sell Yellurgad fort also known as Rajahansagad and there has been apprehension of Bhimgad fort being sold in the light of the fact that 47 acres of land adjacent to the fort has been already sold to a Kerala based firm. Private mining interests are taking advantage of the situation to carry on illegal mining.


Illegal mining has been going on in the valley for decades with the help of powerful vested interests.


Large scale illegal mining – Kalmani Village in Khanapur Taluk – Pic by Srihari Kugaji

Illegal tree felling also continues with a powerful timber lobby. Timber felling also clears the way for manganese mining. Large-scale felling of trees has also been going on by various gangs in connivance with forest officials.

Large scale tree felling & burning of forests on the steep precipitous slopes – Maan village, Chorla, Khanapur taluk – Pic by Srihari Kugaji


Large-scale monoculture plantations of acacia (Australian) and mangium are being plantednot only in the heart of denuded forests but also in the rich grasslands between the forestexpanses and over the plateau. This disturbs the very composition of the flora itself adversely affecting the dependent fauna, particularly birds, bees and insects.


a) A sponge iron plant has been set up in Londa, just south of the Mahadayi Valley. The project site is within 25 km radius of the Londa Forest range and situated virtually on the crestline of the Western Ghats. In Goa itself, four sponge iron plants are operating in the Sahyadri zone.
b) Goa part of the Madei/Mandovi river basin is also facing considerable amount of pollution and damage.

Mining dumps along the banks of the Mandovi in Goa –Pic by Mohan Pai

Numerous mining leases for manganese and iron ore have destroyed the wilderness in Goa, leaving its surface looking like a bombed crater. As a result there is considerable sediment load in the rivers. It is estimated that at least 70,000 of run-off materials are dumped in the Mandovi river. The worst affected rivers are the Mandovi and its two tributaries – Dicholi and Khandepar. According to Goa University researchers there are 27 major mines within the Mandovi river basin. Tata Energy Research Institute which prepared “Area-wise Environmental Quality Plan” states in it report that “ around 21,000 hectares of private and forest land, which accounts for at least 18% of Goa’s private and Government forest, has been lost due to mining”. • POACHING There is widespread poaching both on Karnataka and Goa side. Hunting parties come from places like Mumbai with sophisticated gear for game that includes deer, wild boar, bear, bison, jungle fowl and panthers.


Much more threatening of all the threats is the energetic resurrection of the Karnataka Government’s decades old projects of diversion of the Mahadayi waters into the Malaprabha river along with the Mahadayi Valley power projects.

Kalasa Nala Dam Site at Kankumbi – Pic by Mohan Pai

The Malaprabha story



The Malaprabha Reservoir Project at Naviluteertha in Belgaum district Karnataka was completed in 1974 to irrigate an area of 2,18,000 hectare in Dharwad, Belgaum and Bijapur districts. What was envisaged during the planning of the project as the “cropping pattern” and what exists today is a complete contrast. Crops like paddy, sugarcane and horticulture which are water guzzlers, seem to have replaced the traditional cropping pattern. In the last thirty years four sugar mills have come up in the Malaprabha basin, apart from many others in neighbouring areas. The traditional four-month cultivation cycle has found it difficult to resist the profit-driven approach of growing of the 11-month water intensive crops. The farmers at the head and mid reaches of the irrigated belt are using water of the east-flowing Malaprabha by employing electric pumps. As a result the tail-end villages are facing an acute state of drought. There is almost a sense of doom in the Malaprabha basin with water scarcity and environmental deterioration. The Malaprabha dam since its completion thirty years ago has filled to capacity only thrice. The hills of the eastern plains in the area are denuded and extensively deforested and as a result there is a decrease in the rainfall. Drinking water supply has been affected seriously. Villagers gathering around a single tap with red, green, yellow plastic pots to collect their little share of water is a common sight.

Malaprabha is a much bigger stream than the Mahadayi. According to a former Conservator of Forests, Government of Karnataka, it was the wanton deforestation of the Jamboti area of Khanapur that was primarily responsible for the present state of the Malaprabha river. As a result the Renuka Sagar Reservoir has been affected seriously failing to fulfill the targets.


The proposed Mahadayi River Valley scheme involves building six dams on the Mahadayi and its tributaries near Kankumbi-Chola to divert water into the Malaprabha, While the Mahadayi hydroelectric project will have five more dams on the tributaries to produce of power. The main diversion dam on the Mahadyi known as Kotni dam, is also designed to produce power, apart from diverting water into the Malaprabha above Khanapur.


Foundatiom markingsfor Mhadei Dam at Kotni – Pic by Mohan Pai

These dams will be: one on Kalsa (below its confluence with Surla), one on Haltar Nullha, diverting its water into Kalsa reservoir near Chorla and three small dams on Potni Nullha above Kankumbi (it meets Tilari river in Maharashtra), interconnected and led into Kalsa reservoir. Kalsa reservoir, cumulatively then, is diverted to the Malaprabha through a tunnel near Kankumbi. The water from the main Kotni dam is to be led through a 5.5 km tunnel into the Malaprabha at Asoga near Khanapur.

These six diversion dams involve 1.6 km of dam length, 6.4 km of tunnels through forested ridges, and 3.5 km of open channels as excavations. Areas of submersion amount to 4,300 acres of prime forests and 1000 acre of dry and wet agricultural land. The second project – Mahadayi Hydroelectric project with twin purpose Kotni dam and dams on the tributaries of Irti, Bail and Andhari will submerge another 400 acres of pristine forests bringing the total area of submersion to 5,700 acre including a few villages. The diversion dam on Kalasa (below its confluence with Surla river) will be depleting the waters of Surla river. Surla river makes a beautiful waterfall in the Chorla Ghat and this will turn into a mere trickle like the Jog falls. Besides, the reduction in waters of Surla river will alter the ecology of Sattari Taluk affecting its agriculture, fishery and its economy.

South of the Mahadayi river, two more dams have been planned at Palna and Katla on Dudhsagar (Khandepar) river which forms the source of Dudhsagar Waterfalls in Goa. These dams will reduce this beautiful falls to a sorry state of a trickle just like the famed Jog falls. But more serious will be the consequences for Khandepar river, the waters of which will be considerably reduced. The reservoir at Opa which meets the drinking water needs of Ponda will be seriously affected. River Khandepar is the main tributary of the Mandovi and this will ultimately reduce the inflow in the Mandovi.

A sizeable area will have to be cleared to accommodate the labour and it can be expected that the forests will be further damaged for the requirement of their fire-wood. Within an area of 20-25 km there will be as many as 11 dams and extensive excavation, blasting, etc on account of tunnels and channels. All these activities will seriously disturb and wipe out the wildlife of the area.

The Kalasa-Bhandura water diversion scheme on which the work has already commenced is going to submerge about 723 ha(Kalasa 320 ha & Bhandura 403 ha). Should Karnataka go ahead with the Kotni Hydroelectric & diversion project on the scale that it has been planned the total area to be submerged will be 2145 ha forests plus another 330 ha of forest land for roads, dams power houses, township, field offices, etc. The villages that will be submerged, some them completely and some partially are: Kankumbi, Parwad, Chorla, Kongla, Kirwale and Kabnail, Gavali, Pastoli, Nerse, Jamgaon, Mugwede, Chapoli, Jamgaon and Kavale

Another Malaprabha ?

The question to be posed here is, considering the imbalance existing in the Malaprabha basin, to what extent will the diversion from the Mahadayi will really solve the problem. And at what cost ? As long as the exploitation of water resources in the Malaprabha basin continues, no matter how much water and from where we divert it, we are likely to face the same situation in the near future. As outlined above, the environmental cost of the “developmental scheme” will be devastating.
The denuded Malaprabha Valley in Khanapur taluka bereft of tree cover – Pic by Mohan Pai

Malaprabha basin itself provides a potent pointer. Barely 10 km away from the Mahadayi valley separated by Jamboti ridge, the Malaprabha basin has witnessed marked deforestation, denudation, water scarcity and environmental deterioration within a span of 32 years.

The forest cover of Belgaum district would be reduced from 13% to 8% after releasing the forest land to Mahadayi Diversion and Hydro-electric project. Reduction in forest cover would have considerable effect on the climate – reduction in rainfall, temperature and humidity.

What the Mahadayi project is set to do is to destroy permanently an area, rich in biodiversity, which ranks second in India after Sundarbans and eighth in the world as the finest tiger habitat and is home to many species of flora and fauna including endangered Wroughton’s Freetailed bat and Theobald’s Tomb bat. Barapedi caves in the Mahadyi valley is the only place where Wroughton’s Free-tailed bat is found in the whole world and Theobald’s Tomb bat is rare. Apart from Krishnapur caves it survives only in two other places in India.

Forest destruction spree

In the words of a retired Conservator of Forest, Government of Karnataka “In the name of development the Karnataka Power Corporation has ruined much of our forests and so far more than one lakh hectares has already been destroyed in Sharavathi, Kadra, Kodasalli, Supa, etc. The same fate has fallen on Bedthi – Aghanashini valley forest. And now, it is the turn of Mahadayi. KPC should stop this forest destruction spree immediately other wise we will have to pay heavy price for it”. He also adds “It is not prudent move to destroy forest for electricity. Let it be generated by some other means”

Stockpile of timber near Amgaon – Pic by Srihari Kugaji

Deforestation and the Global Carbon Cycle

Carbon dioxide ( CO2) is the major gas involved in the greenhouse effect, which causes global warming. All the things that produce CO2 (like car burning gas) and the things that consume Co2 (growing plants) are involved in the “global carbon cycle”.

Tropical forests hold an immense amount of carbon, which joins with oxygen to form CO2. The plants and soil of tropical forests hold 460-575 billion metric tons of carbon worldwide. Each acre of tropical forest stores about 180 metric tons of carbon.

Deforestation increases the amount of CO2 and other trace gases in the atmosphere. When a forest is cut and replaced by cropland and pastures, the carbon that was stored in the tree trunks (wood is about 50% carbon) joins with oxygen and is released into the atmosphere as Co2. The loss of forests has a great effect on the global carbon cycle. From 1850 to 1990, deforestation worldwide (including that in the United States) released 122 billion metric tons of carbon into the atmosphere, with the current rate being 1.6 billion metric tons per year. In comparison all the fossil fuels (coal, oil and gas) burned during a year release about 6 billion tons per year.

Releasing CO2 into the atmosphere increases the greenhouse effect, and may raise global temperature. The role of fossil fuels burned by cars and industry is well known, but tropical deforestation releases about 25% of the amount released by fossil fuel burning. Tropical deforestation, therefore, contributes a significant part of the increasing CO2 in the atmosphere.

Mahadayi/Mandovi River Valley, India – Part III

By Mohan Pai

Ecological Impact of the Mahadayi
Water Diversion on Goa
The construction work on the Kalasa-Bhandura diversion dam for which the Deputy Chief Minister of Karnataka laid the foundation stone on September 22, 2006 at Kankumbi near Goa-Karnataka border is progressing rapidly. The project is threatening to wipe out this millennia old culture and society. Goa, although a small state, is one of the most prosperous state of the Indian union, paying the highest per capita tax and earn the highest per capita foreign exchange. Mining, tourism, corporate taxes, income tax, excise etc. net about Rs. 8,000 crores an annum to the National Exchequer.
The State of Goa is the smallest of all the States in the country yet, it shows an astonishing diversity of endemic species, habitats and ecosystems. Goa is under the influence of two global biomes – the marine biome of the Arabian Sea and the terrestrial forest biome of the Western Ghats. Within this geographical canvas are a wide range of ecosystems and habitats e.g. forests, Ghats, alluvial plains, coasts, rivers, estuaries, mangroves, wetlands, etc.
Madei river at Ganjem, Ponda taluka, Goa – Pic by Mohan Pai

Madei/Mandovi is the largest river in Goa which drains almost all of northern and central Goa with the basin area of 1,580 sq km or 43% of Goa’s total land area. Any tempering with its headwaters will seriously disturb its natural ecology and will damage the ecosystem of the entire river basin in Goa.
The livelihood of 296 villages in the talukas of Tiswadi, Bardez, Bicholim, Sanguem and Ponda depends on the resources of Madei/Mandovi waters. It will also affect the Zuari river basin which is linked with the Mandovi through the Cumbharjua canal.
The change in the Mandovi’s profile will also adversely alter the ecology of its estuarine, thickly populated islands of Chorao, Diwar, Corjuem, Jua, Cumbharjua, etc.

The Salinity Factor

The fresh water flow from the Mahadayi river in Khanapur taluka maintains the Mandovi. The Mandovi is a tidal estuary which means that it is an extended arm of the sea with tidal salt water intrusion. The fresh water flow keeps the salinity at a certain level. Reduction in the fresh water flow will disturb the fresh water regime by pushing up the salinity to a much higher level.
At present the salt water ingress and the tidal influence is felt 36 km upstream beyond Ganjem or nearly 70% of the river’s length in Goa. Reduction in the fresh water flow from Karnataka would completely alter the river profile by moving the estuarine front deeper even beyond Valpoi.
Out of the total drainage area of 1,580 sq km 509 sq km is affected by salinity and in another 540 sq km local conditions do not permit any water resource conservation schemes and that leaves only 531 sq km drainage in Goa which could be utilised. The increase in the salinity level will have a detrimental effect on Goa’s entire coastal ecosystem not only jeopardising Goa’s khazan lands, mangroves, avifauna, agriculture, fisheries and river navigation but also its drinking water storages and treatment plants at Sanqulim, Opa and other places sharply reducing the drinking water availability in the river basin.
Forests & Wildlife
The Madei river waters sustain the forests and the wildlife of the Madei Wildlife Sanctuary in Sattari taluka, Bhagawan Mahavir Wildlife Sanctuary and Molem National Park in Sanguem taluka and Bondla Wildlife Sanctuary.

Tree Frog – Pic by Mohan Pai


The reduction in the Mahadayi waters will not only decimate this area (448.5 sq km) but will result in decimating surrounding forests since the whole belt is one contiguous belt of wilderness.

  Gaur or Indian Bison, the State Animal of Goa

The whole of Sattari taluka depends on the waters of Madei for its agriculture including the centuries old method of ‘Puran Sheti’ and the Vasant Bhandaras – lift irrigation employed by most of the villages. These 27 odd villages will face a total ruin.
Khazan fields – intricate system of dykes & sluice gates – Pic by Mohan Pai

Khazan lands are saline floodplains covering an area of about 17,500 ha which have been reclaimed over centuries (Historical records of the 6th century mention Khazan lands) by constructing an intricate system of bunds (dykes) and sluice gates. Khazan lands are ecologically, economically and socially very important for agriculture and piscine culture. This unique system is based on the ecology of the area that includes the present level of salinity of the water. About 2,000 ha are under dense mangrove vegetation. The mangroves help protect the outside of the mud and laterite bunds that enclose the Khazan. Mussels, clams, oysters, crabs and prawns are harvested and the fish and shellfish sustain a large population of indigenous and migratory birds. Reduction in fresh water flow will push up the salinity to a much higher level which may result in the Khazan lands becoming unproductive, affecting thousands of people depending on the Khazan lands.
Khazan field – Sluice gate – Pic by Mohan Pai

(Kulagar in Sattari – Kulagars are hill slope terraces where arecanut and coconut plantationsalong with climbers like betel leaves, pepper, etc. are cultivated. Banana, mango, jackfruit, pineapple, kokum, chillies, turmeric are also being cultivated in kulagars) – Pic by Mohan Pai

Other plantation crops grown in Goa are the bamboo, the banana and mango, bhirand or kokum is also an important plantation crop which forms a part of daily diet. It is used as a garnish to give an acidic taste to curries and vegetable as well as in the preparation of cooling kokum syrup during the hot summer months.
River Navigation

The Mandovi estuary is navigable round the year up to about 45 km from the mouth upstream and is one of the two main waterways of Goa mainly used for transporting iron ore barges of capacity 1,000 – 1,500 tons and transported to the Mormugao Port for export. The depth of estuary varies from 8-10 m at the mouth to less than 2 m.

Mouth of the River Mandovi – Barge carrying iron-ore – Pic by Mohan Pai

Fishing is a major industry in Goa and over 40,000 people are dependent on fisheries for their livelihood. Out of 11 talukas of the state, fisherman fro 8 talukas are involved in fishing. Fish curry and rice is a staple food of Goan people.

Fisherwomen of Britona – Pic by Mohan Pai

The inland catch from the rivers was 3,749 tonnes as against the total catch of 73,135 tonnes (2001). There are landing centres for inland fisheries all along the banks of the Mandovi. The reduction in the water level and the deeper ingress of salt water will affect the fishing due to barriers to fish migration and this will reduce the fish catch. The tourism industry in Goa depends on the local fish produce which will definitely face problems.
The mangroves will be also affected and the shellfish breeding will be depleted and the aqua farms along the river banks also will face problems.


Goa’s sandy beaches are major tourist attraction. Goa is an international tourist destination and tourism is the most important component of Goa’s economy providing employment related opportunities to the local population. Tourist arrivals amounted to 2.3 million in 2005 exceeding the local population by almost a million. Number of hotels and resorts, residential dwellings, commercial establishments, beach side entertainment centres/eat outs have changed the landscape of the coastal strip with activities that follow such a coastal tourism.
Tourists at CalangutePic by Mohan Pai

The Government has laid special emphasis on creating an attractive image for this international destination by developing infrastructure and diversifying a beach oriented tourism to other forms of tourism such as heritage tourism, eco-tourism, adventure and aqua-sports, etc. And there is an attempt to shift developmental activities towards hinterlands and backwaters as well as the Western Ghat forests in the form of eco-tourism. The other tourist attractions are the wildlife sanctuaries and the waterfalls of Dudhsagar which is a main tourist attraction as well as Surla waterfalls and Vajra Sakhala waterfalls in Chorla Ghat which will be reduced to a trickle due to reduced waters.

Watersports – Northern beaches of Goa Pic by Mohan Pai

Seismic threat

Karnataka’s project with as many as 11 dams to be located within an area of 50 km radius have been planned in an area much prone to earthquakes. Two large dams – Supa reservoir and Codasalli are just 50 and 35 km away respectively from the Mahadayi project area. Since the project area is bordering Goa, Goa will also be very vulnerable for any seismic disturbances.

As a result of shortage of water staple produce of rice, pulses and cereals may get affected. The plantation crops such as cashew, coconut and arecanut which are largest plantation crops in Goa are bound to suffer. The largest size of cashew plantations are located in the Madei/Mandovi river basin in the talukas of Sattari, Bicholim and Bardez. The area under arecanut is 2,000 hectares and almost half of it is in Ponda taluka.


Mahadayi/Mandovi River Valley, India – Part IV

By Mohan Pai


The MAHADAYI in Karnataka

The Mahadayi after Vajrapoha waterfalls before the confluence with Bail Nadi – Pic by Srihari Kugaji

The Mahadayi river originates in the Western Ghats of Khanapur taluka, Belgaum district, Karnataka. As the streams of the Sahyadris go, the west- flowing streams are short, swift-flowing, and plunge over precipitous escarpments to discharge their waters into the Arabian Sea. As they plunge towards the coastal strip, they pass through deep gorges creating spectacular waterfalls. The Mahadayi river follows this pattern and is a comparatively small stream with a total length of just about 87 km.- 35 km. in Karnataka and 52 km. in Goa.
Degaon in Khanapur Taluka – the birth place of the Mahadayi river – Pic by Srihari Kugaji
The Mahadayi rises on the eastern slopes of the Sahyadri’s crestline near Degaon village. The origin of the Mahadayi is a multitude of streams from within the fan shaped surrounding hills capped by dense, pristine forests.
Gavali village also claims the origin of the river Mahadayi – Temple and tank, is said to be the source of the Mahadayi – Pic by Mohan Pai
It flows eastward for a short distance and then loops into an arc around the ridges and turns westward across the crestline into Goa. Both, the Malaprabha and the Mahadayi run parallel to each other for some distance but flow in the opposite directions.

Iskcon is setting up a large complex in the Mahadayi Valley near Amgaon. ISCKON has already acquired about 500 acres of land. The project is intended for the development of agriculture, horticulture and medicinal plants with a view to help the local population – Pic by Mohan Pai
Between the Malaprabha river at Kankumbi in the north, Khanapur to the east, Anmod ghat on the Goa highway to the south and Molem/Madei wildlife sanctuaries across the crestline in Goa to the west, the Mahadayi valley with its luxurious forest covers an area of approximately 750 sq. km.
The valley is studded with graceful peaks, deep gorges, thick pristine monsoon forests and flat terraces of paddy fields at the bottom.
Bail Nadi near Amgaon – Pic by Mohan Pai

As many as 75 big and small streams join the Mahadayi at various stages increasing its volume and velocity. The main tributaries of the Mahadayi in the upper and middle catchment areas in Karnataka are small streams of an average length of 5 to 10 km. and as one follows the flow, they are: Right Bank: Bhandura Nala near Kongla, Singar Nala, Doli Nala, Kotni Nala, Irti Nala, Bail Nadi. Left Bank: Pansheer Nala, Madhuhalla Nala.
Confluence of the Mahadayi & Bail Nadi – Pic by Srihari Kugaji
These two streams arise on the crest line astride Talewadi and rush down on either side of the Barapedi caves within a km of each other near Krishnapur in the lower loop.
Vanrachi Khadi – ‘the monkey gorge – Pic by Srihari Kugaji

North of the loop near Kankumbi in the catchment area of Malaprabha river, two potent streams – Kalasa and Surla (Bhandura nala) join east of Chorla and flow across the crestline as Surla river in Goa emptying into the Madei above Valpoi at Nanode in Goa. These two streams are very important and major streams that feed the Mahadayi river.

Jamboti forests – Pic by Mohan Pai

The valley is a scenic treat and one of the richest reservoirs of biodiversity in the world and reflects the complexity in plant, animal and bird life and is home to endangered bat species. The valley is comparable to the Silent valley of Kerala in its significance and an important biological and ecological remaining pocket in the Western Ghats.
Bamboo bridge across the Bhandura Nala – Pic by Mohan Pai
About thirty villages scattered over the area remain poor, ill-served and rejected in the midst of thick resource-rich forests.

 Pastoli Village – Pic by Lt. Col. Ravinder Kumar

The ruins of Bhimgad, an old Maratha fort is located north-east of Molem wildlife sanctuary in Goa and north of Dandeli widlife sanctuary in Uttara Kannada. The area forms a core part of the Western Ghats.

Krishnapur – ampitheatre-like rocky outcrop. Krishnapur is just 2.5 km from Goa border and is home to a rare species of bats – Theobald’s Tomb bat – Pic by Srihari Kugaji

Vertical rock cave ampitheatres of Krishnapur near Goa border are gigantic wall formations 1000-1500 ft in height. The caves are extremely difficult to access, have remained untouched and are nature’s secret providing haven to a large number of floral and faunal species.
Stone icon in a sacred grove at Amgaon – Pic by Srihari Kugaji
The steep drop of over 300 metres near Krishnapur and over 400 metres near Bhimgad to the valley down below is breathtaking. Thereafter, the land rises to the north of the Mahadayi to peaks of about 700 metres at Kedi Paunda and Tamadi Mokh.
Over 2,000 year old Salactite formation – Pic by Srihari Kugaji
12 km from Jamboti is Vajra Poha waterfalls. Here the river Mahadayi is joined by two other streams – Maradha nala and Pansheer nala, creating the magnificent Vajra Poha waterfalls.
Vajra Poha Waterfalls near Bhimgad on the Mahadayi – Pic by Srihari Kugaji
The Mahadayi takes a leap of over 150 ft. with rapids above and below the waterfalls.
Nersa Village
The village of Nersa in Khanapur nestles in the thick forests of Mahadayi valley.
Nersa Village – Pic by Mohan Pai
One of the proposed dams is to be builtclose to this village on Bhandura/Singar Nala confluence, submerging a sizeable area and threatening the very existence of this village.
The Hermitage Farms, a popular ecoresort in Nersa – Pic by Mohan Pai
Tribal Art – Wall Murals at Hermitage Farms done by Gavali tribesman at Nersa – Pic by Mohan Pai

Dam site at Kongla – the confluence of Bhandura & Singar nala near Nersa village – Pic by Mohan Pai

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