Dr. Jitendra Sinha

1. 1
Basics of Ground Water
Speaker
Dr. Jitendra Sinha, Associate Professor
Department of Soil and Water Engineering,
SVCAETRS, FAE, IGKV, Raipur
jsvenusmars@gmail.com, 7000633581

2. • Groundwater, water that occurs below the surface of
Earth, where it occupies all or part of the void spaces in
soils or geologic strata. ... It is also called subsurface water
to distinguish it from surface water, which is found in large
bodies like the oceans or lakes or which flows overland in
streams.
• Groundwater is the water found underground in the cracks
and spaces in soil, sand and rock. It is stored in and moves
slowly through geologic formations of soil, sand and rocks
called aquifers.
2

3. • Groundwater is water that exists underground in saturated zones
beneath the land surface. The upper surface of the saturated
zone is called the water table. ... It fills the pores and fractures in
underground materials such as sand, gravel, and other rock, much
the same way that water fills a sponge.
• Groundwater, which is in aquifers below the surface of the Earth,
is one of the Nation's most important natural resources. ... It
often takes more work and costs more to access groundwater as
opposed to surface water, but where there is little water on the
land surface, groundwater can supply the water needs of people.
3

4. • Generally, both ground water and surface water can
provide safe drinking water, as long as the sources are not
polluted and the water is sufficiently treated. ... Through
wells, ground water can be tapped where it is need, whereas
surface waters are concentrated in lakes and streams.
• Groundwater can be found in aquifers. An aquifer is a body
of water-saturated sediment or rock in which water can move
readily. There are two main types of aquifers: unconfined and
confined. An unconfined aquifer is a partially or fully filled
aquifer that is exposed to the surface of the land.
4

5. • Ground water can be obtained by drilling or digging wells. A
well is usually a pipe in the ground that fills with ground water.
This water can then be brought to the land surface by a pump.
Shallow wells may go dry if the water table falls below the
bottom of the well, as illustrated at right.
• In fact, there is a over a thousand times more water in the
ground than is in all the world's rivers and lakes.
Some water underlies the Earth's surface almost everywhere,
beneath hills, mountains, plains, and deserts. ... Groundwater
is a part of the natural water cycle
5

6. • How do I find my water table?
• The most reliable method of obtaining the depth to the water table at
any given time is to measure the water level in a shallow well
with a tape. If no wells are available, surface geophysical methods can
sometimes be used, depending on surface accessibility for placing
electric or acoustic probes.
• What is the benefit of groundwater recharge?
• Groundwater recharge can act as a barrier to seawater intrusion in
coastal basins and to the migration of contaminants. Other
potential benefits include improving flows in rivers and streams, flood
control, and wildlife and bird habitat.
6

7. 4 Types Of Water
• Surface Water. Surface waters include streams,
rivers, lakes, reservoirs, and wetlands. ...
• Ground Water. Groundwater, which makes up
around 22% of the water we use, is the water
beneath the earth's surface filling cracks and other
openings in beds of rock and sand. ...
• Wastewater
• Stormwater
Then we have:
Blue water, Green water, Grey water, Black water
Any idea?
7

9. Occurrence of ground water in alluvial
formation

10. Occurrence of ground water in hard
rock formation
9/8/2020

15. 15
Source: Water Wells and Pumps, Michael and Khepar

16. Per capita water availability reducing
Year Water Availability
(cu.m.)/pp/yr
1951 5177
2001 1820
2025 1341
Falkenmark Water Stress Indicator
water stress areas < 1700 Cu.m./pp/yr
Many parts of India is under water stress in whole
of the year or in some parts of the year

17. Pattern of water use
 Agriculture ~92% (50% from GW)
 Domestic ~ 5% (>85% rural and >50% urban from GW)
 Industry ~3% (>50% from GW )
Different sources of Irrigation
39%
13%
48%
Major & Medium Irrigation
Minor(S urface Water)
Minor(Ground Water)

18. Groundwater Reservoirs / Water Bearing Formations
Aquifer, Aquiclude, Aquitard and Aquifuge
Aquifers
1. Unconfined Aquifers / WT aquifer
2. Confined Aquifers (Artesian Aquifers /
Pressure Aquifers / Flowing Aquifers)
3. Semi-confined aquifers (Leaky confined
aquifers)
4. Perched aquifer
5. Semi-unconfined aquifers
6. Aquifers bounded by recharge boundaries
7. Aquifers bounded by barrier boundaries
8. Idealized aquifers
18

19.  Idealized aquifers- homogeneous, isotropic and infinite in
areal extension
Interstices and Porosity
Void ratio
Specific yield (Sy)
Specific retention (Sr)
Four parameters for an aquifer
 Coefficient of Permeability or Hydraulic Conductivity K
 Transmissivity or Coefficient of Transmissivity T
 Storativity / Coefficient of storage S
 Drainage factor D or B
Some characters for confined beds
 Hydraulic resistance, C
 Leakage coefficient or Leakance, L
 Leakage factor B
Hydraulic Diffusivity (D) 19

20. • Ground Water: Sources of groundwater Meteoric Water –
It is the water derived from precipitation (rain and snow) although bulk
of the rain water or melt water from snow and ice reaches the sea
through the surface flows or runoffs a considerable part of
precipitation gradually infiltrates into ground water. This infiltrated
water continue its downward journey till it reaches the zone of
saturation to become the ground water in the aquifer. • Almost entire
water obtained from ground water supplies belongs to this category.
• Ground Water Connote Water • This is the water present in the
rocks right from the time of their deposition in an aqueous
environment. During the process of formation of sedimentary rock
in a lake or sea or river, depositions is followed by compaction,
which leads to the squeezing out of most of the water present
between the sediments. Sometimes however, incomplete
compaction may cause retention of some water by these rocks
which is known as connote water. And it may be found in rocks like
limestone, sandstone and gravels. It is saline in nature and is of no
importance as a source for exploitable groundwater.
20

21. • Ground Water Juvenile Water • It is also called
magmatic water and is of only theoretical
importance as far as water supply scheme is
concerned. It is the water found in the cracks or
crevices or porous of rocks due to condensation
of steam emanating from hot molten masses or
magmas existing below the surface of the earth.
Some hot springs and geysers are clearly derived
from juvenile water.
21

22. • Ground Water Distribution: The water that goes below the
surface of the land may be found to exist in two main zones or
environments classified as Vadose Water and phreatic water or
groundwater
• In the vadose water zone itself, three different types of
environment are distinguished; soil water, intermediate vadose
water and capillary water.
• The soil water forms a thin layer confined to the near surface
depth of the land. It may occur at depth between 1.0 to 9 m and
is held up by the root zone of vegetable cover of the globe It is
lost to the atmosphere by transpiration and evaporation.
• The intermediate vadose zone occurs immediately below the
zone of soil water. It is in fact a zone of non saturation; water in
this zone is moving downward under the influence of gravity. It is
generally of smaller thickness and may be even absent in many
cases. The above zones are sometimes collectively referred as
zone of aeration. 22

23. • The zone of capillary water, also called as capillary fringe., is present only in
soil and rocks of fine particles size underlying the vadose zone. In the fine
particle size zone, groundwater is drawn upward by capillary action,
sometimes to height of 2-3 m above saturated zone lying underneath.
Growth of vegetation in some desert is very often dependent on presence
of capillary fringe.
• Ground Water The Phreatic Water Zone, also known as zone of saturation
lies below the capillary fringe and is the water held in this zone that is
called groundwater in the real sense. The upper surface of water in the
zone marks the water table in the area. In this zone the layers or bodies of
rocks which are porous and permeable, have all their open spaces such as
pores, cavities, cracks etc. completely filled with water. All these openings
are interconnected, so that a well dug into this openings are completely
filled with water, there is no or very little downward movement of
groundwater. In all ground water exploration programmes, the main
objective is to locate this zone and determine its extent, geometry and
character.
• Forms of Subsurface Water • Water in the soil mantle is called subsurface
water and is considered in two zones • Saturated Zone • Aeration Zone.23

24. • Saturated Zone • This Zone is also known as groundwater zone in which all the
pores of the soil are filled with water. The water table forms the upper limit
and marks a free surface, i.e. a surface having atmospheric pressure.
• Zone of Aeration • In this zone the soil pores are only partially saturated with
water. The spaces between the land surface and the water table marks the
extent of this zone. The zone of aeration has three subzones.
• Soil water zone • This lies close to the ground surface in the major band of the
vegetation from which the water is lost to the atmosphere by
evapotranspiration. Capillary Fringe • In this the water is held by the capillary
action. This zone extends from water table upwards to the limit of the capillary
rise. Intermediate Zone • This lies between the soil water zone and the
capillary fringe. The soil texture and moisture content and vary from region to
region. The soil moisture in the zone of aeration is of importance in
agricultural practices and irrigation engineering.
• Saturated Formations • All earth materials from soils to rocks have pore
spaces. Although these pores are completely saturated with water table below,
from the groundwater utilization aspect only such material through which
water moves easily and hence can be extracted with ease are significant.
• On this basis the saturated formation are classified into four categories. •
Aquifer • Aqitard • Aquiclude • Aquifuge
24

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26. 26

27. 27
Aquifer
An aquifer is a geological unit that is saturated and permeable
enough to yield sufficient amount of water to wells.
Aquitard
Aquitard is a geological unit of low permeability that can store
groundwater and also transmit it slowly from one aquifer to
another.
Aquiclude
Aquiclude is an impermeable geological unit that does not transmit
any water at all.
Aquifuge
The term Aquifuge is sometimes used synonymously with Aquiclude.
However, there is a minor difference that the Aquiclude may have
some water storage whereas Aquifuge may not.

28. 28
Unconfined aquifers
 Dewatering .
 This results in significant volumes of water being released from storage
per unit volume of earth material in the cone of depression.
Confined aquifers
 No Dewatering
 Pumping causes a decrease in head and an accompanying decrease in
water pressure in the aquifer within the cone of depression.
 This decrease in water pressure allows the water to expand slightly and
causes a slight relaxation of the solid skeleton
 The volume of water released from storage per unit volume of earth
material in the cone of depression in a confined aquifer is small
Release of water from confined and unconfined aquifers

29. 29
Isotropic and Anisotropic
The Isotropy means that parameters does not vary with
direction.
Anisotropy indicates that the parameters vary with respect to
direction.
The parameter mostly we consider is Hydraulic Conductivity.
The directions we consider normally are the Directions of
Coordinate axes viz. X, Y, Z

30. 30
Homogeneous and Heterogeneous
The Homogeneity means that the parameters do not vary with
respect to location.
On the contrary, The Heterogeneity means that the parameters do
vary with respect to location.
The parameter mostly we consider is Hydraulic Conductivity.

31. 31
Steady State & Unsteady State Flow
Steady State Flow:
Theoretically the inflows into the system are equal
to the outflows from the system. Hence There will
not be any change in head over time.
Unsteady State or Transient Flow
Theoretically the inflows into the system are not
equal to the outflows from the system. Hence This
will be reflected as change in head over time.
:

32. •Rainfall
•Runoff
•Interflow
•Infiltration
•Percolation
•Soil water zone
•Zone of aeration
•Capillary fringe
•Water table
Recharge is defined as the downward flow of water reaching
the water table forming an addition to the ground water
reservoir.
Recharge Processes

33. Recharge Worthy Area
Hilly areas with slope >20 % are to be
demarcated as areas not suitable for recharge.

34. • Water in storage is the volume, that underlies a given area
of land surface.
• It represents the volume of water that could be recovered if
that area of aquifer were pumped dry.
Water in Storage

35. Ground Water Resources
Ground Water
Resources
Static Resource Dynamic Resource
Amount of
groundwater
available in the
permeable portion of
the aquifer below the
zone of water level
fluctuation.
Amount of
groundwater available
in the zone of water
level fluctuation.

36. Static and Dynamic GW Resources
Static
Resource
Dynamic
Resource
Fluctuation of
Water Table

37. Unsaturated zone
Saturated zone
Rainfall
Evapotranspiration
Pumping
Baseflow
River/Stream
Infiltration
Water Table
Changes in ground water reserve involves
RECHARGE: DISCHARGE:
Rainfall Evapotranspiration
Recharge from Rivers/Canals Pumping
Recharge from ponds Baseflow
Recharge from irrigation fields
Dynamics of Ground Water Reservoir

38. Basic Equation
Inflow-Outflow=Change in Storage
Dynamic Resource
Static Resorce
Seepage
from
canals
Return flow
from Irrigation
Seepage
from tanks
and ponds
Draft for
Irrigation
Draft for
domestic and
industrial use
Natural Losses
Rainfall
Ground Water Resource Estimation
Using GEC’97 Methodology

39. Inflow Components
 Rainfall Recharge
 Recharge From canals
 Recharge From Surface Water Irrigation
 Recharge From Ground Water Irrigation
 Recharge From Tanks & Ponds
 Recharge From Water Conservation
Structures
Ground Water Resource Estimation
Using GEC’97 Methodology

40. Outflow Components
Gross Draft
Ground Water Resource Estimation
Using GEC’97 Methodology

41. Draft can be of three types
1. Domestic draft
2. Irrigation draft
3. Industrial draft
Estimation Of Ground Water Draft

42. Domestic Draft
Well Census Method
No of different types of abstraction structures
Unit draft
Requirement Method
Population census
Per-capita requirement
Estimation Of Ground Water Draft

43. Irrigation Draft
Well Census Method
No. of different types of abstraction structures
Unit draft
Cropping Pattern Method
Cropping pattern
Crop water requirement
Power Consumption Method
Total power consumed
Unit power required for unit water lift
Estimation Of Ground Water Draft

44. Industrial Draft
Well Census Method
No. of different types of abstraction structures
Unit draft
Power Consumption Method
Total power consumed
Unit power required for unit water lift
Estimation Of Ground Water Draft

45. Water Well
• It is a shaft or hole, usually vertical,
excavated in earth for bringing ground
water to the surface.
45

46. The objective of well
• To provide good quality water,
• To provide a sufficient quantity of water,
• To provide water for a long time, and
• To provide water at low cost
46

47. The water wells sites are taken in
a) The point at which aquifer having high potential to
provide sufficient quantity of water to well
b) Around 50 m away from contamination sites,
c) Choose an area that is not prone to flooding
d) An appropriate distance from another production
wells
47

48. Abstraction structures
 Open dug well – small diameter Open well &
large diameter irrigation well
 Tube well
 Filter point well
 Bore well
 Surangam / Tunnel well
 Auto flow well / Artesian well / Free Flow Well48

49. Surangam
49

50. How water is tapped through water-wells?
 1. Drilling Operation
 2. Lowering of Assembly & Fitting of
Pump
 3. Development & Utilization of well
Water saturated
zone
50

51. Sources of fresh water on Earth
GROUNDWATER

52. GROUNDWATER
water in pores between
sediments
water in fractures, faults, cracks
water in larger
openings like vugs
or caves

53. GROUNDWATER
high porosity
--well sorted
low porosity---
poorly sorted
high porosity-- small platy
sediments—well sorted
most sandstones most conglomerates—
filling of openings
mudstones
and shales
low porosity—igneous and
metamorphic rocks

54. GROUNDWATER
high permeability—most
sandy materials--sandstones
high permeability—well
connected cracks
low permeability—mudstones-
shales low permeability--pumice

55. GROUNDWATER
• specific yield
– the percent water obtained from a substance
• specific retention
– the percent water retained by a substance after water
extraction
– an example of a non rock substance displaying specific yield
and retention would be a sponge in which after squeezing out
all water there still remains some water

56. GROUNDWATER
Unconfined
water
free to move up,
but not down
aquitard--aquiclude

57. GROUNDWATER
aquitard--aquiclude
confined water

58. Groundwater zones
GROUNDWATER
Zone of
Saturation

59. Groundwater zones
GROUNDWATER
Vadose or
Aeration
zone
Capillary
Fringe Area
Water Table

60. GROUNDWATER
vadose (aeration)
zone--unsaturated zone of saturation
water table

61. GROUNDWATER• changing levels of water table
– lowering (discharge) of water table takes place if the following usage
is greater than replenishment to zone of saturation
» continued pumping of groundwater
» plant usage
» leaking of water at the Earth’s surface into streams and lakes
– rising (recharge) of water table
» rate of replenishment (primarily by infiltration) is greater than
rate of depletion
» a spring is a natural surface emission of groundwater--
streams can form this way and many streams in the
Ozarks are spring-fed--a hot spring is about 10-15 degrees
F warmer than local annual mean air temperature
because of an association of water with subsurface
igneous intrusion

62. Mammoth Hot Springs in
Yellowstone National Park
GROUNDWATER

63. Old Faithful Geyser in Yellowstone National Park
A geyser is a hot spring which ejects steam
and water at the surface with great force
and in some cases at a consistent interval
(see example below)

64. GROUNDWATER
• interrelationship of groundwater and streams
– in some cases streams can directly supply groundwater and
vice versa
» an effluent (gaining) stream is supplied by groundwater
and abundant in humid climates— a type of spring

65. GROUNDWATER» an influent (losing) stream supplies water to the zone of
saturation and is characteristic for arid climates— not a spring

66. GROUNDWATER
a spring forming a river or lake a spring gushing out
from cracks
More Kinds of Springs

67. GROUNDWATER
springs from
limestone aquifers
springs from faults
or fractures etc.
spring from water
forced up
encountering a less
or non permeable
rock

68. A spring related to a perched water table
(this arises when there is groundwater in the zone of
aeration above the main or regional water table)

69. GROUNDWATER• pumping of groundwater
– heavy pumping can cause a cone of depression of the water from
drawdown and may leave many shallower wells dry at the surface

70. Confined artesian water
GROUNDWATER

71. GROUNDWATER
Most caves form below the water table,
these formed above the water table

72. GROUNDWATER
– Surface features
• Karst topography is a pitted looking Earth surface resulting
from subsurface solution action and include sinkholes and
solution valleys--enormous sinkholes are an example of mass
wasting

73. GROUNDWATER– Saltwater encroachment and pollution of groundwater
• pumping effects or mixing of groundwater and saltwater
near ocean areas can cause undesirable effects or pumping
too much water can cause the rising of salt water

74. GROUNDWATER– Septic tank leaks
• Sequiota Springs in Springfield is a good example of this

75. Another example of septic tank
leakage

76. What is the water table?
Zone of aeration-
Pore spaces
contain mostly air
Zone of
saturation-pore
spaces contain
mostly water
WATER TABLE-
TOP OF THE
ZONE OF
SATURATION

77. OBJECTIVE OF GW MONITORING
The main objectives of the GW regime
monitoring are ;
• To obtain the information on GW
quantity & quality data through
representative observation wells
• To record the response of GW
systems to a natural/artificial
recharge and output.

78. The Monitoring Cycle
Definition of
information
needed
Design
monitoring
program
Data collection
Data storage and
interpretation

79. Types of data for Groundwater Management
DATA TYPE BASELINE DATA (from archives)
TIME-VARIANT DATA
(from field stations)
Groundwater
Occurrence
& Aquifer
Properties
hydrogeologic logs, grdwater
levels, quality, etc.
 pumping tests
 grdwater level
monitoring
 grdwater quality
monitoring
Groundwater
use
water well pump installations
Water use inventories
 Population registers &
forecasts
Irrigation energy
consumption
 water well
abstraction
monitoring
(direct/indirect)
 grdwater level
variations
Supporting
Information
 climatic data
 land-use inventories
 geologic maps/sections
 riverflow gauging
 meteorologic
observations
 satellite land-use

80. Organizations involved
• CGWB
• State Ground Water Board
• Agricultural Department
• Irrigation Department
• R & D Organization

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86. 86

87. REFERENCES
1. Water Wells and Pumps: AM Michael &
Khepar
2. courses.missouristate.edu › creative ›
PPTglg110 › gro...
3. Watershed Hydrology, R. Suresh, Standard
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