environmental aspects of river valley

Environmental Aspect of River Valley Project Dam

ENVIRONMENTAL ASPECTS OF RIVER VALLEY

PROJECTS DAMS

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ABSTRACT

The paper presents an overview of Environmental Effects associated

with development and exploitation of River Valley Projects in India . The

construction of Dam and Reservoir for irrigation , hydropower , for water

supply may creat number of primary and secondary Environmental

degradation processes . On the river site it includes submergence of land ,

dislocation of human habitats , change in scenic value , change in Ground

Water conditions and alteration of flora and fauna . It resulting lake

environment may be preferred over the existing environment having degraded

forest land . The down stream pattern of river is change , change in aquatic

and riparian vegetation , variation in aquatic life . Construction of a project in

surrounding catchment area affecting it’s ecology .There are some positive

effects of this projects such as the exploitation of water resources for

irrigation , hydro-power , flood moderation . It also make the positive impact on

the environment of command area with improvement in Agriculture ,

Horticulture . The over all effect of these change in improvement in quality of

life and poverty alleviation . With increasing awareness for preservation of

Environment it has been realised that developing activities should go hand in

hand with efforts to maintain ecological and environmental balance . The

important facts about the River Valley Projects ( DAMS) and their

environmental impacts have been highlighted in the paper .

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INTRODUCTION

India is a land of rivers and our economy is predominantly based on

agriculture. Development of river valley projects had become a life line for

progress and prosperity for the country. But these projects imparts some

adverse effects on environment which includes physical dimensions like

productivity of down-stream agricultural fields , as well as it also affects the

social dimensions like population resettlement , submergence of habitation .

The environmental effects may be direct or indirect.

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NEED OF DAMS

Due to peculiar characteristics of Indian monsoon about 85 – 90 % of

annual surface water is available during a short period of 3 – 4 months. This is

a great unevenness in the availability of water over time and space, the growth

in population . Hence large storage capacity reservoir required for irrigation,

hydro-power generation, domestic and industrial water supply. Flood causes

immense damage to property and suffering to millions each year; this can not

be regulated with out storage.

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ENVIRONMENTAL EFFECTS OF RIVER VALLEY

PROJECTS (DAMS)

River Valley Project has positive as well as negative impacts on the

environment. River Valley Projects invariably change the river flow

characteristics and echo-systems regimes of The command area. Following

are the effects –

1} ECOLOGICAL EFFECTS:-

On reservoir site : -

It includes submergence of different kinds of land, dislocation of habitats,

change in scenic value, modification of the micro climate of the region,

alteration in flora and fauna. In short it resulting Lake Environment may be

preferred over the existing environment having degraded forest land.

On down stream site: -

Down stream flow pattern of river is changed; change in aquatic and

vegetation take place, variation in aquatic life. The capacity of river to flush the

pollutants accumulate during the non rainy season may be reduced which

leads to pollution.

2} DEFORESTATION:-

This is un avoidable in areas to be submerged under water. As in case

of impoundment, during construction the forest coming under various

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components, such as dam seat, access roads, quarries, other civil works. In “

NEERA – DEOGHAR ” project at Bhor ( in Pune dist.) the submergence area

is about 1528 ha out of which 55.51 ha is forest area and in “WAGHUR ”

project at Raipur ( in Jalgaon dist.) the submergence area of forest is about

397.41 ha . Which shows the lot of deforestation take place.

3} EFFECT ON WILD LIFE:-

Almost all reservoirs are located in hilly and forested areas which are

the habitat of wild life.

4} HEALTH IMPACTS:-

It is a very important point of discussion as the ill effect of river valley

project. It believed that water impoundment give rise to increasing scope for

breeding mosquitoes. Which may give rise to incident of malaria and other

mosquito-bourn diseases, also the other water bourn diseases. Soil bourn

parasitic and protozoan induction tends to increase due to rising of water and

also due to higher atmospheric humidity. These ill effects are mostly found in

the wet area.

5} DURING CONSTRUCTION:-

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Environmental impact during dam construction are mostly direct and of

short duration. The impacts such as deterioration of water quality in down

stream areas increase in noise level.

6} SOIL EROSION, SILTING OF RESERVOIR AND ON DOWN

STREAM SIDE:-

The river valley projects do not cause any soil erosion. In fact such

projects act as major check-dams where excessive silt gets trapped and

siltation on down stream side reduced. Reservoir have not accelerated the

rate of siltation.

7} WATER LOGGING:-

In many of the irrigation projects, the experience is that the soil in the

command area to become water logged. An area is said to be water logged,

when the water table rises to such an extent that soil pores in that root zone of

crops become saturated resulting in restriction of the normal circulation of air,

the decline in the level of oxygen and increase in the level of carbon-dioxide.

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THESE ARE THE ILL EFFECTS OF THE RIVER VALLEY PROJECT

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Following are the positive effects of the river valley project

1} Change in climate:-

Moderate change in temperature and humidity are mostly beneficial.

2} Tourism and recreation:-

The for water sports may be created in this projects. These projects

lead to social and cultural improvements. The Vrindavan Garden,

Dnyaneshwar Uadyan and Bhakra Dam are the great tourist attraction.

3} Health impacts:-

It provides dependable source of drinking water for the dry reason and

it would be improves the health in that region.

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SUGGESTED ENVIRONMENTAL SAFE GUARDS

1} Rehabilitation and Resettlement:-

There is a provision for more liberal compensation, amenities, land and

employment for displaced population.

2} Compensatory Afforastration:-

With enforcement of replacement of forest submerged by compensatory

afforestation. Also, additional vegeted covers along the rim of the reservoir

compensate the forest loss within the reservoir.

3} Protection of flora and fauna:-

The common effect of reservoir on wild life involved are removal of

feedings area, loss of habitat, limitation on mobility. It can be reduced by

making proper planning and making provision of alternative feeding areas and

habitat.

4} Fisheries development

5} Command area development.

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CASE SYUDY :- ( WAGHUR DAM)

Location: - Waghur river, in Tapi Basin.

Village – Raipur Tal. And Dist. Jalgaon

Maharashtra .

Catchment area :- 1 , 01 , 300 ha .

Command area :- No . of villages benefited = 60

Drinking water for Jalgaon city and 7 villages .

Environmental Impacts and Assesment :-

1} Vegetation and Plants :-

No. of species recorded = 142

Dry deciduous forest .

Most of the submergence was un irrigated and cultivated land .

Additional 78.62 ha of Reserved forest is required for the project .

2} Faunal Diversity :-

No. of Bird species observed = 64

No. of Butterflies species observed = 50

No. of Mammal observed = 8

No. of Fish species observed = 11

3} Positive Impacts :-

a) Drinking water for Jalgaon city and 7 villages .

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b) Improved aesthetic value of the area with additional potential of

tourism development .

c) Development of fisheries .

d) River flow regulated making optimum resource use .

e)1 MW Power generation .

f) Economic development promotion in Command Area through

irrigated agriculture .

g) Development of Local Tourism .

4} Negative Impacts :-

a) Change in microclimate

b) Loss of vegetation and fauna .

c) Change in landscape

d) Alteration to Topography .

5} Impacts to be Mitigated through EMP :-

a) Land pollution by debris deposition .

b) Silting of reservoir .

c) Water logging in the command area .

d) Loss of forest cover / habitats .

6} Conclusion : -

a) The positive effects weigh more than the losses .

b) Project is necessary as the Jalgaon City is facing acute

shortage of Drinking Water .

c) No rare and endangered species of flora and fauna is affected .

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CONCLUSION

1. Nothing can be 100 % perfect . Engineers are human , they are far from

perfect .

2. In the world there are 2000 study done by the WORLA RESOURCES

INSTITUTE which altered that the destroy of wild life habitats along the

rivers and in costal delts by reducing water flow.

3. Irresponsible media coverage concerning the “destruction of flora and

fauna” by the large water projects have helped to create misconceptions in

public mind .

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REFERENCES

1) BOOKS :

Environmental Impacts of Water Resources Development

(By: R. S. Goel)

Environmental Engineering

(By : Gerard Kielley)

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INDEX

Sr. No. Particulars Page No.

1. ABSTRACT 1

2. INTRODUCTION 2

3. NEED OF DAMS 3

4. ENVIRONMENTAL EFFECTS OF RIVER VALLEY PROJECTS (DAMS) 4

5. SUGGESTED ENVIRONMENTAL SAFE GUARDS 8

6. CASE SYUDY :- ( WAGHUR DAM) 9

7. CONCLUSION 11

8. REFERENCES 12

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environmental aspects of river valley

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