1. DEPARTMENT OF CIVIL ENGINEERING
SATARA COLLEGE OF ENGINEERING & MANAGEMENT
LIMB SATARA-415001
2. A PRESENTATION ON
“GEOCHEMICAL INVESTIGATION OF GROUNDWATER OF
KRISHNA BASIN ”
BY
NAME ROLL NO
BHOSALE AKSHAY 11
JADHAV ANANT 12
JADHAV VAIBHAV 13
PATIL PRASHANT 14
SHINDE VIKRAM 15
4. TABLE OF CONTENTS
INTRODUCTION
GROUNDWATER CONTAMINATION
GEOCHEMISTRY OF GROUNWATER
STUDY AREA
METHODOLOGY
TABLE OF PERMISSIBLE LIMITS
GRAPHICAL REPRESENTATION OF RESULTS
RESULTS & CONCLUSION
5. 1.INTRODUCTION
1.1 IMPORTANCE OF GROUNDWATER
Most important natural resource
Approx. 97.2% salty
2.8% fresh water out of this 20%
water is used for purposes like domestic, industrial, commercial, etc.
In rural areas, ground water is preferred source of water due to non-
availability or poor quality of other water resources.
More than 90% of the rural population uses groundwater for domestic
purposes and KRISHNA basin is no exception to this.
6. Water is also an essential part of Geological cycle as it converts the rocks into
clays, sand and transports them to the oceans where they become raw
material of the future continents.
The hydrological cycle.
7. 1.2 GROUNDWATER POTENTIAL IN INDIA
Parameter
Unit
( Billion cubic
meter)/year
Annual water
availability
1869
Usable water 1123
Surface water 690
Ground water 433
The overall contribution of rainfall to the
country’s annual ground water resource is
68% and the share of other resources, such
as canal seepage, return flow from
irrigation, recharge from tanks, ponds and
water conservation structures taken
together is 32%
8. 1.3 QUALITY OF WATER
“Water quality” is a term used here to express the suitability of water to sustain
various uses or processes.
particular use will have certain requirements for the physical, chemical or
biological characteristics of water.
The composition of surface and underground waters is dependent on natural
factors geological, topographical, hydrological and biological, etc.
Human activities such as the discharge of domestic, industrial, urban and other
wastewaters into the watercourse (whether intentional or accidental) and the
spreading of chemicals on agricultural land in the drainage basin are also
effecting the groundwater quality.
9. The quality of ground water is much better than surface water, because
surface water contains large amount of suspended impurities, whereas
ground water is free from it.
But sometimes ground water dissolves mineral, salts, etc. which come in
contact while being in movement.
10. 1.4 NEED FOR MORE RESEARCH
Due to various human activities, the quality of groundwater is being
AFFECTED.
The commonly observed contaminants include bacteria, phosphates and
heavy metals, etc.
Numerous water bodies have became temporarily or permanently unsuitable for
human use.
It has been pointed out that nearly 60% of all the districts in the country have
issues related to either availability of ground water or quality of ground water
or both.
In such areas, physico-chemical investigation of water quality could serve as a
convenient tool for examining intensity of contamination.
11. 1.5 AIMS AND OBJECTIVES
Understanding the effects of human factors on the geochemistry of
groundwater of Krishna basin.
To establish groundwater sampling network on the basis of land use
information.
To investigate the impact of geological, hydrological and land use factors on
the geochemistry of groundwater.
To delineate potable/non-potable areas of groundwater occurrence by using
geochemical data.
To find out suitability of groundwater for drinking and agricultural
purposes.
12. 2. GROUNWATER CONTAMINATION
The ground water is the most prime water
. The quality of water depends on
o The composition of recharge water
o Interactions between the water and soil
o The rocks with which it comes into contact in unsaturated zones
o Residence time and the reactions that take place within the aquifer
Earlier the ground water was supposed to be chemically and
microbiologically non-polluted. But in recent decades, different types of
organic and inorganic contaminants found in ground water.
13. 2.2 How does the ground water gets polluted or contaminated?
Depending on its physical, chemical and biological properties, contaminant
that has been released into the environment may move within an aquifer in
the same manner that ground water moves.
Just as ground water generally moves slowly, so do contaminants in ground
water. Because of this slow movement, contaminants tend to remain
concentrated in the form of a plume that flows along the same path as the ground
water.
Generally, the greater the distance between a source of contamination and a
ground water source, the more likely that natural processes will reduce the
impacts of contamination. Processes such as oxidation, biological degradation
and adsorption may take place in the soil layers of the unsaturated zone and
reduce the concentration of a contaminant before it reaches ground water.
14. 2.3 Sources of ground water contamination
Natural sources
• Some substances found naturally in rocks or soils, such as iron, manganese,
arsenic, chlorides, fluorides, sulfates or radionuclides, can become dissolved in
ground water.
• Naturally occurring substances, such as decaying organic matter, can move in
ground water as particles.
Improper disposal Hazardous waste
• Hazardous waste should always be disposed of properly, unless it may cause
pollution to ground water.
• Many chemicals should not be disposed of in household septic system,
including soils, lawn and garden chemicals, etc.
15. Landfills
• Solid waste is disposed of in thousands of municipal and industrial
landfills throughout the country. Chemicals that should be disposed of in
hazardous waste landfills sometimes end up in municipal landfills
• New landfills are required to have clay or synthetic liners and leachate
(liquid from a landfill containing contaminants) collection systems to
protect ground water.
• Closed landfills can continue to pose a ground water contamination
threat if they are not capped with an impermeable material (such as clay)
before closure to prevent the leaching of contaminants by precipitation.
16. 2.4 Effects of ground water contamination
Contamination of ground water can result in poor drinking water quality, loss of
water supply, degraded surface water systems, high cleanup costs, high costs for
alternative water supplies, and/or potential health problems.
In terms of water supply, in some instances, ground water contamination is so
severe that the water supply must be abandoned as a source of drinking water.
17. 3. GEOCHEMISTRY OF GROUNDWATER
3.1 INTRODUCTION
The word “Geochemistry”, generally refers to the study of earth crust from
chemical point of view. The chemical aspects of hydrogeology are quite different
from physical aspects.
The purpose of studying geochemistry is to conclude an integrated effect of
lithology, land use and hydrogeological factors on the composition of groundwater
of Krishna basin.
18. 3.2 DISSOLVED CONSTITUENTS IN GROUNDWATER
The ground water contains dissolved, suspended and colloidal matter in it. It is also
natural habitat for numerous micro-organisms. The dissolved constituents are mainly
derived from interaction of ground water with aquifer rocks. The constituents
dissolving in ground water are classified as,
1. Major Constituents-
Positively charged cations - Na+, K+, Ca+, and Mg+.
Negatively charged anions – Cl-, SO4
-, NO3
-, CO3
-, HCO-
3
2. Minor Constituents – Fe, Mn, Cu, Zn, Pb, Ag, Hg, As, Al.
In addition to these, pH and Electrical Conductivity are also important
properties of ground water, which should be taken into consideration.
19. 4. STUDY AREA – KRISHNA BASIN
4.1 LOCATION
KRISHNA river basin is located in hilly area region of western ghats.
The KRISHNA river originates in the hilly region of SAHYADRI characterized by
thick lateritic capping.
It occupies an area about 69425 sq.km.
The length of river is about 1300 km.
It includes some villages of three Talukas namely –WAI, SATARA, KARAD and
MAHABALESHWAR in the SATARA district.
20. 4.2 Physiography
Physiographically, Krishna River basin can be divided into three parts as,
Hilly terrain with steep slopes characterizing relatively high altitude source area (700m
to 960m) above mean sea level.
Rolling topography with moderate slopes and moderate altitude covering middle part
of the River basin (600m to 700m) above mean sea level.
Valley floor area with gentle slopes and flat plains at lower altitude (540m to 600m)
above mean sea level.
Due to very rugged topography, large number of streams of different types are present
such as,
• Perennial - having water throughout year
• Seasonal – having water only in rainy season
• Ephemeral – having water only for few days
21. 4.3 GEOLOGY OF STUDY AREA
Geologically, the basalts of the Deccan Volcanic Province characterize the
Krishna Basin.
In general, the basaltic flows are of simple type with maximum thickness
upto 35 meters.
The flows have been separated by thin clayey horizons called as the red beds.
The thickness of the red beds varies from less than a meter to 2 meter.
22. Alluvium
Occurs along the banks of the KRISHNA river and major streams joining the
main stream
Thickness varies 2 to 6 meters
Mainly consists of pebble beds, sand and laterites
ALLUVIUM (LOCALITY-RIVER BANK NEAR WAI)
23. Laterite
Occurs in upstream part in the source of Krishna river
Occur at an elevation of 2500-3000 ft.
Occur as capping over the flat topped basaltic flows
The laterite is the product of chemical weathering of the basalts under tropical
climatic conditions
Chemical weathering gives it red or white colour
Thickness varies 25 to 30 meters
24. Basalts
The basalts constitute the major litho unit in the Krishna basin.
The typical sections of basalts can be observed in the road cut sections and as
well as along the stream banks.
The basalts from the area are dark to grey in colour and fine to medium
grained in texture.
26. Basalts displaying two sets of prominent vertical as well as horizontal joints
can also be seen
Vertically jointed basalts
27. Red boles
Seen at the separation of two basaltic flows
Thickness 2 meters
Red in colour, clayey in texture and ferruginous in character that imparts the
red colour.
28. 5. METHODOLOGY
In order to get an idea about ground water quality, the methodology used
for obtaining reliable and useful data includes selection of sampling sites,
collection of ground water samples and analysis of those samples by suitable
methods available.
Therefore following data steps have undertaken to fulfill the objectives of
this study as well as, to collect reliable data.
1) Selection of suitable groundwater sampling stations
2) Collection of samples
3) Analysis of collected water samples by suitable methods available.
4) Evaluation of water chemistry data obtained.
29. 5.1 SELECTION OF GROUNDWATER SAMPLING STATIONS
The first stage of the planning of the sampling program was the
selection of suitable sampling sites, which are likely to provide the
required data. Thirty-one sampling stations were chosen for the
collection of Groundwater samples.
These wells were broadly classified into two categories:
• Those, which are serving as source of water supply for drinking &
Agricultural purpose.
• Those used for domestic purpose such as washing, bathing etc.
30. 5.2 COLLECTION OF GROUNDWATER SAMPLES
As water is susceptible to changes in composition because of its powerful
solvent properties the following precautions were taken while collecting the
samples,
• The plastic bottles (1lit) were used for the sample collection, as it is resistant to
solution action.
• The containers were thoroughly washed, cleaned and rinsed before every
collection for each station, separate containers were used.
• The water samples from the wells were collected after pumping them for 5 to 10
min to discharge the water remained in the pipe.
• The collected samples were labeled properly and stored in suitable place.
• Physicochemical analysis were carried out within 24 hours after collection of the
samples.
31. 5.3 Analysis of water samples
The groundwater samples collected were subjected to the chemical analysis.
The chemical analysis were carried out for determining the major and minor
constituents present in samples.
The following techniques were employed for the analysis.
a. Volumetric titrimetric methods
To determine Total alkalinity, total hardness and chlorides were
analyzed by this technique.
b. Spectrophotometric methods
To determine the sulphates and nitrates .
32. c. Flame photometric methods
To determine Alkali elements like sodium (Na), Calcium (Ca)and
potassium (K)
d. Atomic absorption spectrophotometric methods
To determine Ca, Mg, Fe, Mn, Cu, Pb, Zn, Ag, etc.
45. 8. CONCLUSION
Aim of the project was to determine the groundwater quality with special
reference to physical and chemical analysis of groundwater.
The tremendous use of fertilizers and expansion of population has changed the
qualities of groundwater. In order to collect the data regarding quality of
groundwater in krishna basin, various physico- chemical laboratory tests were
carried out on collected water samples. The
water samples were collected from 31 sites. The analysis included
determination of pH.Acidity.Alkalinity.Hardness. Ca. Mg, CI, SO4. PO4, K.
Na, Pb. Fe etc.The analytical method included volumetric (Alkalynity.
Hardness, Ca, Mg. and CI), spectrophotometric (SO4. PO4), flame
photometric (Na and K) analysis.
The results of various analysis in the present study reveal the following
information.
