------------------------------------------------------------------------------------------------
Type of Contaminant
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Chemical Micro-biological Physical Radio-chemical
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Inorganic Organic
Cr+3 Cd+2 Zn+2 Pb+2 Detergents Pathogenic Turbidity Radium & other
Fe+2 Ba+2 Mn+3+4 Li+ Alcohols Bacteria Colour Radio-active
K+ Ni+3+4 Ag+ Mo+2 Phenols Sulphate reducing; Particles nuclides
U Se Hg+2 Al+3 Gasoline Iron related & Odour
Cu+2 F CN Cl- Pesticides Slime Producing Hardness
B+3 SO4-2 NO3- Dyes Taste
NO2- NH PO-2 (salinity)
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Contamination of Ground Waters Due To Sea Water Intrusion
India has a very long coastal line stretching from Rann of Kutch in Gujarat to Konkan,
Malabar coast to Kanyakumari in the south to northwards along the Coromondal coast to
Sunderbans in West Bengal (Fig.2). The climatic conditions, which affect ground water
recharge, vary considerably with Kutch having arid to semi-arid climate, while the Malabar
coast has tropical humid climate (rainfall over 250 cm annually). The rainfall on the east
coast also varies being about 80 cm at Kanyakumari and 100 cm on the Madras coast.
However, further northwards, the rainfall again increases being 150-160 cm in the
Subarnrekha and Ganga deltaic areas.
Coastal aquifers particularly unconfined aquifers are also subject to saline as well as to
contamination by tidal waters; the distnce to which these factors affect ground water quality
depends upon several factors including topography of the area.
Pollution of Ground Waters By Nitrates
Nitrogen plays an important role in plant metabolism. It is an essential constituent of
different types of metabolic active compounds. Plants obtain most of their N-requirements
for growth by absorbing NO3- and NH4+ from the soil. For humans, an important
consideration is the fact that NO3- ions can be readily converted to NO2-, which oxidizes
haemoglobin to methomoglobin, a pigment ,which is incapable of acting as oxygen carrier in
blood. It has been well documented that milk feeds prepared for infants in water containing
over 45 mg NO3-/L has been responsible for infant methemoglobinemia (blue baby disease)
which resulted in many fatal cases in the period 1960-65. Most health authorities limit nitrate
content in potable waters to 45-50 mg NO3-/L.
Studies on nitrate concentrations in ground waters from unconfined or water table aquifers in
India have shown that in many cases the NO3 concentrations exceed 100 mg. NO3-/L and in
exceptional cases even 1000 mg. NO3-/L (Handa, 1992). Since the use of nitrogenous
fertilizers (urea, calcium ammonium nitrate, ammonium sulphate etc.) has increased
considerably during the past few years, it is generally presumed that the main reason behind
such anomalously high concentrations of NO3- ions, is the leaching down of nitrate enriched
return irrigation flows (Handa, 1992).
Ground Water Pollution Due to Solid Wastes (MUNICIPAL)
In India about 0.33 kg/capita/day of commercial and domestic wastes are produced. With an
urban population of about 200 million, it is estimated that about 24 X 106 tonnes of solid
wastes are produced annually. The waste is often disposed off in low lying areas. During the
rainy season, some of the rainwater percolates through the waste producing leaching
comprising of chemical, microbiological products produced by interaction of solid waste
with water. The leachates generally contain Cl-, SO2-, Ca2+, Mg2+, NH3- NO2-, Fe2+, organic
compounds etc besides some gaseous products like CH4, H2S and CO2 etc. which are partly
lost to the atmosphere and may also be partly present in the leachates; the exact composition
of the leachate however vary with the composition of the saline waste, temperature, pH, Eh
and moisture content prevailing in the solid waste-water mixture.
Proper location of refuse dumping sites and hygienic sealing are quite effective in lessening
ground water pollution from these sources.
Ground Water Contamination From Human and Animal Wastes
Human and animal excreta (faeces, dung, urine etc.) contain a variety of pollutants,
inorganic, organic & micro-biological, which can affect ground water quality adversely.
Humans excrete 100-400 g of faeces (wet weight) and 1.0-1.3 kg of urine daily, the drysolids
content ranging from 30-60 g in faeces and 50-70 g in urine. Taking mean values and
assuming population of India to be 8.50 millions, the human wastes produced would contain
about 4 million tonnes of N, 1.29 million tonnes of P (as P2O5) and 0.93 million tonnes of K
(K2O). However, a portion of this waste is lost as runoff, a portion is lost by microbial
decomposition, a portion is held up in soil and balance may be leached to the saturated zone.
Similarly, considerable amount of N, P & K compounds are released to theenvironment
through animal wastes, a portion of the which may reach the ground water body, affecting its
quality adversely.
Proper collection and disposal of human nd animal wastes can mitigate the problems
associalted with ground water pollution from leachates of these sources.
Pollution of Ground Waters Due to Mining Activities:
The working of mines results, directly or indirectly in deterioration of ground water quality.
Production of leachates from piled up solid wastes or from abandoned mines and production
of acid mine drainage waters may affect ground water quality directly with addition of toxic
wastes into it, while destruction of forest cover, affects recharge and thus may affect ground
water quality indirectly.
PROBLEMS OF WATERLOGGING AND SOILWATER SALINITY
Waterlogging and salinity are the most serious problems facing the world s irrigated
agriculture. But there can be no two opinions that our long term economic survival depends
upon how we come to terms with the problem raised by soil and water salinity. Waterlogging
and salinity are wide spread in India, but there are means to control these undesirable
processes. Salinity prevention and control in irrigation command areas can be effected
through combination of a number of structural and institutional measures. The choice of the
right combination of interventions can be arrived at through cost effectiveness analysis which
considers both the cost and the efficiency with which it is achieved. Water application at
farm level could be accomplished with reasonable efficiency by precision leveling. More
costly systems like drip and sprinkler irrigation may be adopted where salinity of
underground water is high. If, the technological feasibility exists, vertical drainage could
effectively control watertable.
Salinity is a major problem in India, Pakistan, China, USA, Soviet Union, Australia, Iraq,
Hungary and UAR.
The situation has slightly improved lot but waterlogging and salinity is a still serious problem
in north-west India. In India, as a whole, the irrigated area having waterlogging condition has
been estimated to be 2.46 million ha. while the salt affected area is 8.5 million ha. (Tyagi,
1994).
Waterlogging and Salinity Control Measures Include:
1. Improving irrigation management to reduce the amount of groundwater recharge.
2. Ameliorating salinity effects through sound groundwater management, land use
changes, and development of more salt tolerant crops.
3. Taking actions to lower water table, leaching and evacuation of saline water through
drainage.
CONCLUSIONS
Groundwater use has immensely increased for irrigation, domestic and industrial purposes.
Farmers have growing ambitions in raising high value crops by excessive use of groundwater.
The over exploitation of groundwater is causing resource depletion. Groundwater pollution is
also increasing with industrial, agricultural, urban and rural development. There is a need to
launch comprehensive groundwater management practices including enactment and
implementation of groundwater law to achieve equity, environmental sustainability and
economic efficiency in the real interest of the present and future human generations. This
calls for institutional reforms on priority to reorganise groundwater organs from different
departments into a Central Groundwater Authority for adopting sustainable development and
management practices by formulation of an effective action plan. This may also necessitate
proper education and training of ground water professionals in the Universities by
introducing new academic programmes in groundwater management (Singhal, 1996).
REFERENCES
Handa, B.K., 1992, Status report on Goundwater pollution in India. (Vols. 1 to 4).
Handa, B.K., 1994. Groundwater Contamination in India (Key paper) Proc. Regional
Workshop on Environment Aspects of groundwater Development, Kurukshetra University,
Kurukshetra (Oct., 1994), pp.I-1 to I-33).
Prasad, R.K., 1994. Overexploitation of Groundwater, Associated Phenomenon and
Rehabilitation Measures, (Key paper), Proc. Regional Workshop on Environmental Aspects
of Groundwater Development, Kurukshetra University, Kurukshetra (Oct. 1994), pp. IV-1 to
IV-8.
Saksena, R.S., 1994. Overexploitation of Groundwater in India Problems and Suggested
Measures (Review Paper), Proc. Regional Workshop on Environmental Aspects of
groundwater Development, Kurukshetra University, Kurukshetra (Oct. 1994), pp. IV-9 to IV-
18.
Singhal, D.C., 1996, Environmental Impacts of Groundwater Development (Key Note Paper),
First National Conference on Rural Development and Environment, Jiwaji University,
Gwalior (March, 1996).
Tanwar, B.S., 1994, Environmental Impact of Groundwater Development (Key paper) Proc.
Regional Workshop on Environment Aspects of Groundwater Development, Kurukshetra
University, Kurukshetra (Oct. 1994), pp.II-1 to II-8.
Tyagi, N.K., 1994, Prevention and Amelioration of Waterlogging and Salinity in India: An
Overview (Key Paper), Proc. Regional Workshop on Environmental Aspects of Groundwater
Development (Oct. 1994), Kurukshetra University, Kurukshetra, pp.III-1 to III-10.
tion of hydrometric studies.
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Period between No. of Area vacated by Average recession
observations years the glacier per year
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1935-1956 21.0 52,500 m2 2,500 m2
1956-1962 5.6 36,500 m2 6,158 m2
1962-1971 9.5 1,20,000 m2 12,631 m2
Sept.1971
to 3.8 9,500 m2 2,500 m2
July 1975
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Sahai (1992) has reported that the glacier vacated an area of 0.243 km2 during the last fifty
years (1935-1990). The annual rate of area vacated by the glacier between 1935 and 1971 (36
years) was 8.77 per cent and in the next six years (1971-1977) this value goes upto 10.4
percent. It is, however striking that in the last thirteen years (1977-1990) the area vacated
was exceptionally high 80.8 per cent. Perhaps serious ecological imbalances coupled with
increased human activity have caused its recession during the last three decades.
Sahai (1992) has reported that Geological Survey of India has carried out glaciological
studies pertaining to mass balance on Tipra Bank (1980-1988) and Dunagiri glacier 1984 to
1991 in the Ganga basin. Mention of similar studies on the Gangotri glacier is also found in
the available literature.
Mass balance is an important glaciological parameter as the deviations from steady state
mass balance conditions cause a dynamic response of the glacier, resulting in a change of
flow rate, leading finally to an advance or retreat of the glacier terminus. These effects also
induce the formation of moraines and other morphological features, which allow delineation
of the former extent of glaciers.
Hydrological processes
The quantity and timing of discharge in Bhagirathi river with snow and icemelt components
of runoff depend therefore on amount, incidence and form (liquid or solid) of precipitation,
and on the thermal regime which determines the amount of winter snow pack available and
of the melting of perennial ice throughout summer in these basins which are glacierised. The
timing and intensity of monsoonal rain storm also determines the shapes of the hydrograph.
The Geological Survey of India reported the measurement of discharge by salt-dilution
method in October 1971 towards the end of the ablation season. They found the average
discharge to be 29.5 m3/ sec and pH range 6 to 6.5. In the published Records of the GSI
1973-74,1974-75, 1975-76, 1976-77 and 1989-90 there is no mention of hydrometric studies.
A six month discharge (May to November 1994) hydrograph obtained on Dokriani glacier, a
small glacier in the Bhagirathi river headwaters has shown that the maximum flows take
place in early July when the transient snowline retreats rapidly, however between middle July
and September the glacier melt rate is reduced because of extensive cloud cover over the
entire elevation range of Garhwal Himalaya. But the flows are partially compensated by the
monsoonal precipitation. This type of behavior in the discharge pattern is characteristic of
southern Himalaya glaciers where monsoonal rains are widespread.
HIMALAYAN GLACIERS AS A SUSTAINABLE WATER RESOURCE
The perennial rivers of the Indus, Ganga and Brahamputra river system drain the fertile
agricultural plans of the north, northeast and northwest part of Indian Sub-continent are
mainly snow and glaciers melt fed. The first systematic hydrological studies on proglacial
streams were carried out be Kanwar Sain (1946). However, the most noteworthy work was
done by Gulati (1973, who delineated the glacierized areas in 20 major rivers having their
catchments in the Himalaya (Table 1.3). Aside from these studies no serious efforts have
been made to investigate the impact of Himalayan glaciers on the hydrological regime and
climate of North India.
In view of frequent flooding and drought problems the Department of Sciences and
Technology of the Government of India evolved in 1985 a national coordinated project for
the detailed study of glaciers on the southern slopes on the Himalaya. The main objective of
this programme is to establish a comprehensive date base on all the important glaciers in the
major river basins. A central part of this project to study the hydrological and hydrochemical
aspects of meltwater. The information on meltwater yield, its chemical and sediment
characteristics is vital to the safety and maintenance of the hydroelectric installations and
reservoirs in the outer and inner Himalaya. Recently it was observed that the Bakhra Nangal
reservoir was overdrawing from the ice resources of the Sutlej by 10 per cent to 13 per cent
of the river flow; from this observation it was concluded that the rate at which the glaciers
are melting may lead to their disappearance in future, destroying the ecology of the area and
permanently drying out the perennial rivers (Hasnain, 1989).
The climate and meteorology of the Himalayan controls the water resources. If you look at
the entire area from the far eastern Himalaya to the far western Karakoram, you find that the
monsoon diminishes in intensity and duration as you traverse from east to west. And
concomitantly the importance of snow and ice increases from east to west. There are regional
and vertical differences in the hydrological regimes of the Himalaya with strong seasonality
of precipitation. For example in the eastern Himalaya the summer monsoon causes snow fall
at the higher elevations and ice ablation at the lower elevation simultaneously.
Glaciers, in the Himalaya, are sustainable sources of fresh water. While every summer large
quantities of meltwater flows from them every winter fresh snow is added. the permanent
reservoir of glacier ice is enormous in the Himalaya. therefore, a detailed data base in
required on seasonal and permanent ice cover along with establishment of a hydrometric
network with measurement of climatic variable over the range of elevations in which the
fusion of snow and ice occurs. The principal scientific issues to be focussed in future studies
are:
(1) What are the seasonal variations in the amounts of runoff derived from the melting
snow and ice?
(2) How much do the timing and magnitudes of seasonal variations of runoff change
from year to year, and in response to what synoptic climatic conditions ?
(3) Which hydrometeorological variable at which measurement station are best related to
runoff variations and this will be used to predict variations in meltwater flows?
(4) What delay arises within glacierized basins between melt production and discharge at
the glacier terminus ?
Table 1 : Retreat of important Glaciers in the Himalaya.
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Glacier Period Year Retreat in meters.
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Milam 1849-57 108 1350-after C.P.Vohra.
Pindari 1845-66 121 2840-after C.P.Vohra
1858-1958 100 2600-after Mayewski & Jeschke, 1979.
Gangotri 1935-76 41 600
Bava-Shigri 1890-1906 16 320-after Mayewski & Jeschke,1979.
1906-1945 39 1075-after Srikantia & Padi-1963.
Kolahai (J&K) 1857-1909 52 800-after Mayewski
1912-1961 49 800 and Jeschke,1979.
Machoi (J&K) 1906-1957 51 457-after Tewari, 1971.
Rakhiot 1930-1950 20 600-after Mayewski & Jeschke, 1979.
(Nanga-Parbat)
Chungphar 1930-1950 20 600-after Mayewski & Jeschke, 1979.
(Nanga-Parbat)
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River Major river Mountain area Glacier area Percenta
system (km2) (km2) glaciation
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1. Indus 268842 7890 3.3
2. Jhelum 33670 170 5.0
3. Chenab Indus 27195 2944 10.0
4. Ravi 8092 206 2.5
5. Sutlej 47915 1295 2.7
6. Beas 14504 638 4.4
7. Jamuna 11655 125 1.1
8. Ganga 23501 2312 10.0
9. Ramganga Ganga 6734 3 0.04
10. Kali 16317 997 6.01
11. Karnali 53354 1543 2.9
12. Gandak 37814 1845 4.9
13. Kosi 61901 1281 2.1
14. Tista 12432 495 4.0
15. Raikad Brahmaputra 26418 195 0.7
16. Manas 31080 528 1.7
17. Subansiri 81130 725 4.0
18. Brahmaputra 256928 1080 0.4
19. Dibang 12950 90 0.7
20 Luhit 20720 425 2.01
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