832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 124

eol 11 1st Sem AY2011-12 91920

DNJ

Groundwater

Geology 11 ndash Principles of Geology

A M P Tengonciangamp D D N Javier

Department of Physical Sciences

University of the Philippines Baguio

The Hydrologic Cycle

Precipitation =Runoff + Infiltration + Transpiration + Evaporation

httpgawaterusgsgovedugraphicsearthwheredistributiongifTarbuckamp Lutgens 20xx Earth Science

Earthrsquos Inventory

of WaterSaline

Fresh25 of all the fresh

water on Earth

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 224

eol 11 1st Sem AY2011-12 91920

DNJ

- all water in the ground occupying the pore spaces within rock

and regolith

- that portion of precipitation (rainfall snow etc) which seeps

through the ground and is stored below the surface

Geologic importance erosional agent equalizes streamflow

(reservoir for rivers during periods of no rain)

Economic importance drinking water irrigation livestock power

generation industrial cooling

Groundwater Sources of groundwater

bull Connate water ndash water that has remainedtrapped in a sedimentary rock since the original

sediments were deposited in the water prior tolithification may be very old and saline

bull Meteoric water ndash water of atmospheric originwhich reaches the Earthrsquos surface as rainfall orseepage from surface water bodies

bull Juvenile water ndash original water formed frommagmatic processes has never been in theatmosphere

bull Zone of aeration ndash

unsaturated zone vadose

zone (Lat shallow)

ndash water is able to pass

through to reach the

water-table (vadose

water)

ndash pore spaces are not

completely filled with

water

bull Zone of saturation ndash

phreatic zone (Gr

wellspring)

ndash pore spaces are

saturated with water

bull Water table ndash upper surface

of zone of saturation

The Water Table

-boundary between the

unsaturated (vadose)

zone and saturated zone

of an aquifer

Note

The vadose zone has an

important

environmental role in

groundwater systems

Surface pollutants must

filter through the vadose

zone before entering the

zone of saturation

bull Capillary fringe ndash zone

where water is drawnupward by capillary

action immediately

above the water table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 324

eol 11 1st Sem AY2011-12 91920

DNJ

Water Table

bull Important in predicting

the productivity of wells

bullExplains the changes inflows of springs and

streams

bull Accounts for fluctuation

in levels of lakes

bull Unobservable directly

but can be mapped and

studied in detail in areas

where wells are

numerous

bull The shape of the water

table is usually a subdued

replica of the surfacetopography

bull Irregularities are due to

ndash variations in rainfall

ndash nature of carrying

material

ndash slow and varied

groundwater

movement under

different conditions

downward

movement of

water from the

soil to the water

table

Porosity

bull Measure of how much of a rock is open space

bull Percentage of total volume of rock or sediment thatconsists of pore spaces (absolute porosity)

bull Effective porosity ndash the proportion of the rock or

sediment consisting of interconnected pores

bull Dictates the amount of water stored by material

Porosity in Sediments

Porosity in differentsedimentsA) A porosity of 30 percent

in a reasonably well-sortedsedimentB) A porosity of 15 percentin a poorly sorted sedimentin which fine particles fill

spaces between largergrainsC) Reduction in porosity inan otherwise very poroussediment due to cementthat binds particles together

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 424

eol 11 1st Sem AY2011-12 91920

DNJ

Porosity

bull Primary ndash created by the same

processes that formed the

material

ndash sediments amp sedimentary

rocks

ndash vesicular lava deposits

bull Secondary ndash develops after the

material was formed

ndash rock fractures (joints and

faults)

ndash cavities formed by

dissolution of soluble rocks22

Bedient et al 1999

Typical Values of Porosity

Permeability

bull Measure of the ease with which water can move

through a porous rock

bull The ability of a material to transmit fluid

bull Related to the effective porosity of a material

ndash the smaller the pore spaces the slower the

movement of water

ndash sandstone ndash good permeability

ndash shale ndash poor permeability

Porosity and Permeability

Porous

and

Permeable

Porous but

not

Permeable

Reduced

Porosity and

Permeability

Porosity and Permeability

shale sandstone limestone

Porous and PermeablePorous but not Permeable

Porosity and permeability

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 524

eol 11 1st Sem AY2011-12 91920

DNJ

HYDRAULIC HEAD FLUID POTENTIAL = h (length units)bull Measure of energy potential (essentially is a measure ofelevationalgravitational potential energy)

bull The driving force for groundwater flow

bull

Water flows from high to low fluid potential or hydraulic (even if thismeans it may go uphill)

bull Hydraulic head is used to determine the hydraulic gradient

Hydraulic head = the driving force that moves groundwater Thehydraulic head combines fluid pressure and gradient and can bethought of as the standing elevation that water will rise to in a wellallowed to come to equilibrium with the subsurface Groundwateralways moves from an area of higher hydraulic head to an area of lowerhydraulic head Therefore groundwater not only flows downward it canalso flow laterally or upward

Groundwater Movement

S Hughes 2003

Groundwater Flow Velocity - Darcyrsquos Law

v = K (h1-h2)lv velocity

K hydraulic conductivity

The velocity of groundwater is based on hydraulic conductivity (K)as well as the hydraulic head (I)

The equation to describe the relations between subsurface materialsand the movement of water through them is

Q = KIAQ = Discharge = volumetric flow rate volume of water flowingthrough an aquifer per unit time (m3 day)

A = Area through which the groundwater is flowing cross-sectionalarea of flow (aquifer width x thickness in m 2)

Rearrange the equation to QA = KI known as the flux (v) which isan apparent velocity

Groundwater Movement -- Darcyrsquos Law

S Hughes 2003

Groundwater Movement -- Darcyrsquos Law

Q = KIA -- Henry Darcy 1856 studied water flowing through porous

material His equation describes groundwater flow

Darcyrsquos experiment

bull Water is applied underpressure through end Aflows through the pipe anddischarges at end B

bull Water pressure ismeasured using piezometertubes

Hydraulic head = dh (change in height between A and B)Flow length = dL (distance between the two tubes)Hydraulic gradient (I) = dh dL

S Hughes 2003

High K materials

Groundwater MovementTable 106 in textbook (Keller 2000)

Porosity and hydraulic conductivity (rate at which water moves througha material) of selected earth materials

Hydraulic

Porosity ConductivityMaterial () (mday)

UnconsolidatedClay 45 0041Sand 35 328Gravel 25 2050Gravel and sand 20 820

RockSandstone 15 287Dense limestone or shale 5 0041Granite 1 00041

S Hughes 2003

Hydraulic conductivity = ability of material to allow water to move through itexpressed in terms of mday (distancetime) It is a function of the size andshape of particles and the size shape and connectivity of pore spaces

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 624

eol 11 1st Sem AY2011-12 91920

DNJ

Flow lines

Confining beds

WellsWater table

Millennia

Centuries

Decades

Years

Days

Dischargearea

Unconfinedaquifer

Confinedaquifers

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Years

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining bedsDecades

Years

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Centuries

Decades

Years

Days

Dischargearea

Unconfinedaquifer

Confinedaquifers

WellsWater table

Flow lines

Confining beds

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Millennia

Centuries

Decades

Years

Days

Dischargearea

WellsWater table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 724

eol 11 1st Sem AY2011-12 91920

DNJ

Effluent streams

bull Receive water emergingfrom a submerged spring or

other groundwater seepage

bull The surface of the streamdirectly relates to the watertable thus will rise and fallas the water table rises andfalls

bull Common in temperate totropical climates run yearround

Influent streams

bull May or may not be directly

connected to the water table

bull Supplement the water in the

zone of saturation producing

an upward bulge in the water

table directly underneath

bull Common in arid climates may

be temporary only present

when rainfall or flash flooding

occurs

Groundwater storage amp movement

bull Aquifer ndash permeable rock strata or sediment thattransmits groundwater freely (eg sands gravelsfractured rock)

An aquifer is a formation that allows water to be accessibleat a usable rate

bull Aquitard ndash impermeable rock strata or sedimentthat slows down or retards water movement (egclay non-fractured rock)

bull Aquiclude (aquifuge) ndash porous rock stata or

sediment with poor permeability such that itblocks groundwater movement

Unconfined

Aquifer

They are notsealed off at anypoint

Recharge canoccur anywhere

Water at wtableunder atmpressure

Must lower bucketor pump to accesswater

Unconfined aquifer ndash an aquifer whose upper limit is the water table has no confining

layers that retard vertical water movement

Confined aquifer ndash an aquifer sandwiched between two impermeable strata Confined

aquifers have non-permeable layers above and below the aquifer zone referred

to as aquitards or aquicludes

Unconfined aquifer

-Sealed off

-Transmits waterdown from RA

-Water confined inaquifer unlessdrilled

-Water underhydrostaticpressure

- Water rises wellmay flow

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 824

eol 11 1st Sem AY2011-12 91920

DNJ

Perched aquifer ndash an unconfined groundwater body supported by a

small impermeable or slowly permeable layer

Spring ndash natural flow of groundwater resulting from the intersection

of the water table with the land surface

Springs

bull Form when an aquicludeblocks the downwardmovement of

groundwater and forces itto move laterally towardsa more permeable bed orarea of less confinement

bull Dependent on rock typesand relationshipsprimary amp secondaryporosity and permeability

Porous limestone overlies an impermeable shale unit and a line

of springs occurs along the hillside where the two rock unitsmeet

Springs issue from the contact between a highly jointed lava flow

and the underlying impermeable mudstone

Springs flow from the place where a fault intersects the ground

surface

Springs

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 924

eol 11 1st Sem AY2011-12 91920

DNJ

Springs Desert Oases

Wells

bull Openings bored into the zone of saturationSuccessful andUnsuccessful Wells

Yields to wells from nonhomogeneous rock can bevariableA) wells that penetratefractures in metamorphicand igneous rocks producewater Dry wells result if nowater-bearing fractures areencounteredB) Perched water bodiesabove the main water tableare held up by aquicludes

and provide shallow sourcesof groundwater Wells thatmiss the perched water bodyand do not reach the deeperwater table are dry

Wellsbull Drawdown ndash lowering of water

table resulting from the

removal of water from a well

cone of depression

bull Hydraulic gradient ndash slope of

the water table increases with

more groundwater extraction

thereby increasing the rate of

groundwater flow into the well

Artesian wells

bull Groundwater under pressure rises above the level of the

aquiferbull Conditions for an artesian system

ndash Water must be confined to an aquifer that is inclined so that

one end can receive water

ndash Aquicludes or aquitards both above and below the aquifer

must be present to prevent the water from escaping the

pressure created on the aquifer will cause the water to rise

bull Does not always connote free-flowing surface discharge

bull Nonflowing artesian wells ndash pressure surface is below ground

level

bull Flowing artesian wells ndash pressure surface is above ground level

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1024

eol 11 1st Sem AY2011-12 91920

DNJ

Flowing or Artesian Well Development

Flowing Artesian Wells

groundwater in confined system is

under enough pressure that no well

pumping is needed

The Dakota Aquifer System

Problems with groundwater withdrawal

bull Groundwater depletion or lowering of the water

table

ndash groundwater removed from an aquifer exceeds

the amount produced (ie demand gtgt supply)

ndash caused by

bull too much demand

bull too little recharge

Lowering of the Water Table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 224

eol 11 1st Sem AY2011-12 91920

DNJ

- all water in the ground occupying the pore spaces within rock

and regolith

- that portion of precipitation (rainfall snow etc) which seeps

through the ground and is stored below the surface

Geologic importance erosional agent equalizes streamflow

(reservoir for rivers during periods of no rain)

Economic importance drinking water irrigation livestock power

generation industrial cooling

Groundwater Sources of groundwater

bull Connate water ndash water that has remainedtrapped in a sedimentary rock since the original

sediments were deposited in the water prior tolithification may be very old and saline

bull Meteoric water ndash water of atmospheric originwhich reaches the Earthrsquos surface as rainfall orseepage from surface water bodies

bull Juvenile water ndash original water formed frommagmatic processes has never been in theatmosphere

bull Zone of aeration ndash

unsaturated zone vadose

zone (Lat shallow)

ndash water is able to pass

through to reach the

water-table (vadose

water)

ndash pore spaces are not

completely filled with

water

bull Zone of saturation ndash

phreatic zone (Gr

wellspring)

ndash pore spaces are

saturated with water

bull Water table ndash upper surface

of zone of saturation

The Water Table

-boundary between the

unsaturated (vadose)

zone and saturated zone

of an aquifer

Note

The vadose zone has an

important

environmental role in

groundwater systems

Surface pollutants must

filter through the vadose

zone before entering the

zone of saturation

bull Capillary fringe ndash zone

where water is drawnupward by capillary

action immediately

above the water table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 324

eol 11 1st Sem AY2011-12 91920

DNJ

Water Table

bull Important in predicting

the productivity of wells

bullExplains the changes inflows of springs and

streams

bull Accounts for fluctuation

in levels of lakes

bull Unobservable directly

but can be mapped and

studied in detail in areas

where wells are

numerous

bull The shape of the water

table is usually a subdued

replica of the surfacetopography

bull Irregularities are due to

ndash variations in rainfall

ndash nature of carrying

material

ndash slow and varied

groundwater

movement under

different conditions

downward

movement of

water from the

soil to the water

table

Porosity

bull Measure of how much of a rock is open space

bull Percentage of total volume of rock or sediment thatconsists of pore spaces (absolute porosity)

bull Effective porosity ndash the proportion of the rock or

sediment consisting of interconnected pores

bull Dictates the amount of water stored by material

Porosity in Sediments

Porosity in differentsedimentsA) A porosity of 30 percent

in a reasonably well-sortedsedimentB) A porosity of 15 percentin a poorly sorted sedimentin which fine particles fill

spaces between largergrainsC) Reduction in porosity inan otherwise very poroussediment due to cementthat binds particles together

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 424

eol 11 1st Sem AY2011-12 91920

DNJ

Porosity

bull Primary ndash created by the same

processes that formed the

material

ndash sediments amp sedimentary

rocks

ndash vesicular lava deposits

bull Secondary ndash develops after the

material was formed

ndash rock fractures (joints and

faults)

ndash cavities formed by

dissolution of soluble rocks22

Bedient et al 1999

Typical Values of Porosity

Permeability

bull Measure of the ease with which water can move

through a porous rock

bull The ability of a material to transmit fluid

bull Related to the effective porosity of a material

ndash the smaller the pore spaces the slower the

movement of water

ndash sandstone ndash good permeability

ndash shale ndash poor permeability

Porosity and Permeability

Porous

and

Permeable

Porous but

not

Permeable

Reduced

Porosity and

Permeability

Porosity and Permeability

shale sandstone limestone

Porous and PermeablePorous but not Permeable

Porosity and permeability

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 524

eol 11 1st Sem AY2011-12 91920

DNJ

HYDRAULIC HEAD FLUID POTENTIAL = h (length units)bull Measure of energy potential (essentially is a measure ofelevationalgravitational potential energy)

bull The driving force for groundwater flow

bull

Water flows from high to low fluid potential or hydraulic (even if thismeans it may go uphill)

bull Hydraulic head is used to determine the hydraulic gradient

Hydraulic head = the driving force that moves groundwater Thehydraulic head combines fluid pressure and gradient and can bethought of as the standing elevation that water will rise to in a wellallowed to come to equilibrium with the subsurface Groundwateralways moves from an area of higher hydraulic head to an area of lowerhydraulic head Therefore groundwater not only flows downward it canalso flow laterally or upward

Groundwater Movement

S Hughes 2003

Groundwater Flow Velocity - Darcyrsquos Law

v = K (h1-h2)lv velocity

K hydraulic conductivity

The velocity of groundwater is based on hydraulic conductivity (K)as well as the hydraulic head (I)

The equation to describe the relations between subsurface materialsand the movement of water through them is

Q = KIAQ = Discharge = volumetric flow rate volume of water flowingthrough an aquifer per unit time (m3 day)

A = Area through which the groundwater is flowing cross-sectionalarea of flow (aquifer width x thickness in m 2)

Rearrange the equation to QA = KI known as the flux (v) which isan apparent velocity

Groundwater Movement -- Darcyrsquos Law

S Hughes 2003

Groundwater Movement -- Darcyrsquos Law

Q = KIA -- Henry Darcy 1856 studied water flowing through porous

material His equation describes groundwater flow

Darcyrsquos experiment

bull Water is applied underpressure through end Aflows through the pipe anddischarges at end B

bull Water pressure ismeasured using piezometertubes

Hydraulic head = dh (change in height between A and B)Flow length = dL (distance between the two tubes)Hydraulic gradient (I) = dh dL

S Hughes 2003

High K materials

Groundwater MovementTable 106 in textbook (Keller 2000)

Porosity and hydraulic conductivity (rate at which water moves througha material) of selected earth materials

Hydraulic

Porosity ConductivityMaterial () (mday)

UnconsolidatedClay 45 0041Sand 35 328Gravel 25 2050Gravel and sand 20 820

RockSandstone 15 287Dense limestone or shale 5 0041Granite 1 00041

S Hughes 2003

Hydraulic conductivity = ability of material to allow water to move through itexpressed in terms of mday (distancetime) It is a function of the size andshape of particles and the size shape and connectivity of pore spaces

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 624

eol 11 1st Sem AY2011-12 91920

DNJ

Flow lines

Confining beds

WellsWater table

Millennia

Centuries

Decades

Years

Days

Dischargearea

Unconfinedaquifer

Confinedaquifers

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Years

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining bedsDecades

Years

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Centuries

Decades

Years

Days

Dischargearea

Unconfinedaquifer

Confinedaquifers

WellsWater table

Flow lines

Confining beds

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Millennia

Centuries

Decades

Years

Days

Dischargearea

WellsWater table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 724

eol 11 1st Sem AY2011-12 91920

DNJ

Effluent streams

bull Receive water emergingfrom a submerged spring or

other groundwater seepage

bull The surface of the streamdirectly relates to the watertable thus will rise and fallas the water table rises andfalls

bull Common in temperate totropical climates run yearround

Influent streams

bull May or may not be directly

connected to the water table

bull Supplement the water in the

zone of saturation producing

an upward bulge in the water

table directly underneath

bull Common in arid climates may

be temporary only present

when rainfall or flash flooding

occurs

Groundwater storage amp movement

bull Aquifer ndash permeable rock strata or sediment thattransmits groundwater freely (eg sands gravelsfractured rock)

An aquifer is a formation that allows water to be accessibleat a usable rate

bull Aquitard ndash impermeable rock strata or sedimentthat slows down or retards water movement (egclay non-fractured rock)

bull Aquiclude (aquifuge) ndash porous rock stata or

sediment with poor permeability such that itblocks groundwater movement

Unconfined

Aquifer

They are notsealed off at anypoint

Recharge canoccur anywhere

Water at wtableunder atmpressure

Must lower bucketor pump to accesswater

Unconfined aquifer ndash an aquifer whose upper limit is the water table has no confining

layers that retard vertical water movement

Confined aquifer ndash an aquifer sandwiched between two impermeable strata Confined

aquifers have non-permeable layers above and below the aquifer zone referred

to as aquitards or aquicludes

Unconfined aquifer

-Sealed off

-Transmits waterdown from RA

-Water confined inaquifer unlessdrilled

-Water underhydrostaticpressure

- Water rises wellmay flow

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 824

eol 11 1st Sem AY2011-12 91920

DNJ

Perched aquifer ndash an unconfined groundwater body supported by a

small impermeable or slowly permeable layer

Spring ndash natural flow of groundwater resulting from the intersection

of the water table with the land surface

Springs

bull Form when an aquicludeblocks the downwardmovement of

groundwater and forces itto move laterally towardsa more permeable bed orarea of less confinement

bull Dependent on rock typesand relationshipsprimary amp secondaryporosity and permeability

Porous limestone overlies an impermeable shale unit and a line

of springs occurs along the hillside where the two rock unitsmeet

Springs issue from the contact between a highly jointed lava flow

and the underlying impermeable mudstone

Springs flow from the place where a fault intersects the ground

surface

Springs

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 924

eol 11 1st Sem AY2011-12 91920

DNJ

Springs Desert Oases

Wells

bull Openings bored into the zone of saturationSuccessful andUnsuccessful Wells

Yields to wells from nonhomogeneous rock can bevariableA) wells that penetratefractures in metamorphicand igneous rocks producewater Dry wells result if nowater-bearing fractures areencounteredB) Perched water bodiesabove the main water tableare held up by aquicludes

and provide shallow sourcesof groundwater Wells thatmiss the perched water bodyand do not reach the deeperwater table are dry

Wellsbull Drawdown ndash lowering of water

table resulting from the

removal of water from a well

cone of depression

bull Hydraulic gradient ndash slope of

the water table increases with

more groundwater extraction

thereby increasing the rate of

groundwater flow into the well

Artesian wells

bull Groundwater under pressure rises above the level of the

aquiferbull Conditions for an artesian system

ndash Water must be confined to an aquifer that is inclined so that

one end can receive water

ndash Aquicludes or aquitards both above and below the aquifer

must be present to prevent the water from escaping the

pressure created on the aquifer will cause the water to rise

bull Does not always connote free-flowing surface discharge

bull Nonflowing artesian wells ndash pressure surface is below ground

level

bull Flowing artesian wells ndash pressure surface is above ground level

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1024

eol 11 1st Sem AY2011-12 91920

DNJ

Flowing or Artesian Well Development

Flowing Artesian Wells

groundwater in confined system is

under enough pressure that no well

pumping is needed

The Dakota Aquifer System

Problems with groundwater withdrawal

bull Groundwater depletion or lowering of the water

table

ndash groundwater removed from an aquifer exceeds

the amount produced (ie demand gtgt supply)

ndash caused by

bull too much demand

bull too little recharge

Lowering of the Water Table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 324

eol 11 1st Sem AY2011-12 91920

DNJ

Water Table

bull Important in predicting

the productivity of wells

bullExplains the changes inflows of springs and

streams

bull Accounts for fluctuation

in levels of lakes

bull Unobservable directly

but can be mapped and

studied in detail in areas

where wells are

numerous

bull The shape of the water

table is usually a subdued

replica of the surfacetopography

bull Irregularities are due to

ndash variations in rainfall

ndash nature of carrying

material

ndash slow and varied

groundwater

movement under

different conditions

downward

movement of

water from the

soil to the water

table

Porosity

bull Measure of how much of a rock is open space

bull Percentage of total volume of rock or sediment thatconsists of pore spaces (absolute porosity)

bull Effective porosity ndash the proportion of the rock or

sediment consisting of interconnected pores

bull Dictates the amount of water stored by material

Porosity in Sediments

Porosity in differentsedimentsA) A porosity of 30 percent

in a reasonably well-sortedsedimentB) A porosity of 15 percentin a poorly sorted sedimentin which fine particles fill

spaces between largergrainsC) Reduction in porosity inan otherwise very poroussediment due to cementthat binds particles together

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 424

eol 11 1st Sem AY2011-12 91920

DNJ

Porosity

bull Primary ndash created by the same

processes that formed the

material

ndash sediments amp sedimentary

rocks

ndash vesicular lava deposits

bull Secondary ndash develops after the

material was formed

ndash rock fractures (joints and

faults)

ndash cavities formed by

dissolution of soluble rocks22

Bedient et al 1999

Typical Values of Porosity

Permeability

bull Measure of the ease with which water can move

through a porous rock

bull The ability of a material to transmit fluid

bull Related to the effective porosity of a material

ndash the smaller the pore spaces the slower the

movement of water

ndash sandstone ndash good permeability

ndash shale ndash poor permeability

Porosity and Permeability

Porous

and

Permeable

Porous but

not

Permeable

Reduced

Porosity and

Permeability

Porosity and Permeability

shale sandstone limestone

Porous and PermeablePorous but not Permeable

Porosity and permeability

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 524

eol 11 1st Sem AY2011-12 91920

DNJ

HYDRAULIC HEAD FLUID POTENTIAL = h (length units)bull Measure of energy potential (essentially is a measure ofelevationalgravitational potential energy)

bull The driving force for groundwater flow

bull

Water flows from high to low fluid potential or hydraulic (even if thismeans it may go uphill)

bull Hydraulic head is used to determine the hydraulic gradient

Hydraulic head = the driving force that moves groundwater Thehydraulic head combines fluid pressure and gradient and can bethought of as the standing elevation that water will rise to in a wellallowed to come to equilibrium with the subsurface Groundwateralways moves from an area of higher hydraulic head to an area of lowerhydraulic head Therefore groundwater not only flows downward it canalso flow laterally or upward

Groundwater Movement

S Hughes 2003

Groundwater Flow Velocity - Darcyrsquos Law

v = K (h1-h2)lv velocity

K hydraulic conductivity

The velocity of groundwater is based on hydraulic conductivity (K)as well as the hydraulic head (I)

The equation to describe the relations between subsurface materialsand the movement of water through them is

Q = KIAQ = Discharge = volumetric flow rate volume of water flowingthrough an aquifer per unit time (m3 day)

A = Area through which the groundwater is flowing cross-sectionalarea of flow (aquifer width x thickness in m 2)

Rearrange the equation to QA = KI known as the flux (v) which isan apparent velocity

Groundwater Movement -- Darcyrsquos Law

S Hughes 2003

Groundwater Movement -- Darcyrsquos Law

Q = KIA -- Henry Darcy 1856 studied water flowing through porous

material His equation describes groundwater flow

Darcyrsquos experiment

bull Water is applied underpressure through end Aflows through the pipe anddischarges at end B

bull Water pressure ismeasured using piezometertubes

Hydraulic head = dh (change in height between A and B)Flow length = dL (distance between the two tubes)Hydraulic gradient (I) = dh dL

S Hughes 2003

High K materials

Groundwater MovementTable 106 in textbook (Keller 2000)

Porosity and hydraulic conductivity (rate at which water moves througha material) of selected earth materials

Hydraulic

Porosity ConductivityMaterial () (mday)

UnconsolidatedClay 45 0041Sand 35 328Gravel 25 2050Gravel and sand 20 820

RockSandstone 15 287Dense limestone or shale 5 0041Granite 1 00041

S Hughes 2003

Hydraulic conductivity = ability of material to allow water to move through itexpressed in terms of mday (distancetime) It is a function of the size andshape of particles and the size shape and connectivity of pore spaces

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 624

eol 11 1st Sem AY2011-12 91920

DNJ

Flow lines

Confining beds

WellsWater table

Millennia

Centuries

Decades

Years

Days

Dischargearea

Unconfinedaquifer

Confinedaquifers

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Years

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining bedsDecades

Years

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Centuries

Decades

Years

Days

Dischargearea

Unconfinedaquifer

Confinedaquifers

WellsWater table

Flow lines

Confining beds

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Millennia

Centuries

Decades

Years

Days

Dischargearea

WellsWater table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 724

eol 11 1st Sem AY2011-12 91920

DNJ

Effluent streams

bull Receive water emergingfrom a submerged spring or

other groundwater seepage

bull The surface of the streamdirectly relates to the watertable thus will rise and fallas the water table rises andfalls

bull Common in temperate totropical climates run yearround

Influent streams

bull May or may not be directly

connected to the water table

bull Supplement the water in the

zone of saturation producing

an upward bulge in the water

table directly underneath

bull Common in arid climates may

be temporary only present

when rainfall or flash flooding

occurs

Groundwater storage amp movement

bull Aquifer ndash permeable rock strata or sediment thattransmits groundwater freely (eg sands gravelsfractured rock)

An aquifer is a formation that allows water to be accessibleat a usable rate

bull Aquitard ndash impermeable rock strata or sedimentthat slows down or retards water movement (egclay non-fractured rock)

bull Aquiclude (aquifuge) ndash porous rock stata or

sediment with poor permeability such that itblocks groundwater movement

Unconfined

Aquifer

They are notsealed off at anypoint

Recharge canoccur anywhere

Water at wtableunder atmpressure

Must lower bucketor pump to accesswater

Unconfined aquifer ndash an aquifer whose upper limit is the water table has no confining

layers that retard vertical water movement

Confined aquifer ndash an aquifer sandwiched between two impermeable strata Confined

aquifers have non-permeable layers above and below the aquifer zone referred

to as aquitards or aquicludes

Unconfined aquifer

-Sealed off

-Transmits waterdown from RA

-Water confined inaquifer unlessdrilled

-Water underhydrostaticpressure

- Water rises wellmay flow

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 824

eol 11 1st Sem AY2011-12 91920

DNJ

Perched aquifer ndash an unconfined groundwater body supported by a

small impermeable or slowly permeable layer

Spring ndash natural flow of groundwater resulting from the intersection

of the water table with the land surface

Springs

bull Form when an aquicludeblocks the downwardmovement of

groundwater and forces itto move laterally towardsa more permeable bed orarea of less confinement

bull Dependent on rock typesand relationshipsprimary amp secondaryporosity and permeability

Porous limestone overlies an impermeable shale unit and a line

of springs occurs along the hillside where the two rock unitsmeet

Springs issue from the contact between a highly jointed lava flow

and the underlying impermeable mudstone

Springs flow from the place where a fault intersects the ground

surface

Springs

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 924

eol 11 1st Sem AY2011-12 91920

DNJ

Springs Desert Oases

Wells

bull Openings bored into the zone of saturationSuccessful andUnsuccessful Wells

Yields to wells from nonhomogeneous rock can bevariableA) wells that penetratefractures in metamorphicand igneous rocks producewater Dry wells result if nowater-bearing fractures areencounteredB) Perched water bodiesabove the main water tableare held up by aquicludes

and provide shallow sourcesof groundwater Wells thatmiss the perched water bodyand do not reach the deeperwater table are dry

Wellsbull Drawdown ndash lowering of water

table resulting from the

removal of water from a well

cone of depression

bull Hydraulic gradient ndash slope of

the water table increases with

more groundwater extraction

thereby increasing the rate of

groundwater flow into the well

Artesian wells

bull Groundwater under pressure rises above the level of the

aquiferbull Conditions for an artesian system

ndash Water must be confined to an aquifer that is inclined so that

one end can receive water

ndash Aquicludes or aquitards both above and below the aquifer

must be present to prevent the water from escaping the

pressure created on the aquifer will cause the water to rise

bull Does not always connote free-flowing surface discharge

bull Nonflowing artesian wells ndash pressure surface is below ground

level

bull Flowing artesian wells ndash pressure surface is above ground level

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1024

eol 11 1st Sem AY2011-12 91920

DNJ

Flowing or Artesian Well Development

Flowing Artesian Wells

groundwater in confined system is

under enough pressure that no well

pumping is needed

The Dakota Aquifer System

Problems with groundwater withdrawal

bull Groundwater depletion or lowering of the water

table

ndash groundwater removed from an aquifer exceeds

the amount produced (ie demand gtgt supply)

ndash caused by

bull too much demand

bull too little recharge

Lowering of the Water Table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 424

eol 11 1st Sem AY2011-12 91920

DNJ

Porosity

bull Primary ndash created by the same

processes that formed the

material

ndash sediments amp sedimentary

rocks

ndash vesicular lava deposits

bull Secondary ndash develops after the

material was formed

ndash rock fractures (joints and

faults)

ndash cavities formed by

dissolution of soluble rocks22

Bedient et al 1999

Typical Values of Porosity

Permeability

bull Measure of the ease with which water can move

through a porous rock

bull The ability of a material to transmit fluid

bull Related to the effective porosity of a material

ndash the smaller the pore spaces the slower the

movement of water

ndash sandstone ndash good permeability

ndash shale ndash poor permeability

Porosity and Permeability

Porous

and

Permeable

Porous but

not

Permeable

Reduced

Porosity and

Permeability

Porosity and Permeability

shale sandstone limestone

Porous and PermeablePorous but not Permeable

Porosity and permeability

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 524

eol 11 1st Sem AY2011-12 91920

DNJ

HYDRAULIC HEAD FLUID POTENTIAL = h (length units)bull Measure of energy potential (essentially is a measure ofelevationalgravitational potential energy)

bull The driving force for groundwater flow

bull

Water flows from high to low fluid potential or hydraulic (even if thismeans it may go uphill)

bull Hydraulic head is used to determine the hydraulic gradient

Hydraulic head = the driving force that moves groundwater Thehydraulic head combines fluid pressure and gradient and can bethought of as the standing elevation that water will rise to in a wellallowed to come to equilibrium with the subsurface Groundwateralways moves from an area of higher hydraulic head to an area of lowerhydraulic head Therefore groundwater not only flows downward it canalso flow laterally or upward

Groundwater Movement

S Hughes 2003

Groundwater Flow Velocity - Darcyrsquos Law

v = K (h1-h2)lv velocity

K hydraulic conductivity

The velocity of groundwater is based on hydraulic conductivity (K)as well as the hydraulic head (I)

The equation to describe the relations between subsurface materialsand the movement of water through them is

Q = KIAQ = Discharge = volumetric flow rate volume of water flowingthrough an aquifer per unit time (m3 day)

A = Area through which the groundwater is flowing cross-sectionalarea of flow (aquifer width x thickness in m 2)

Rearrange the equation to QA = KI known as the flux (v) which isan apparent velocity

Groundwater Movement -- Darcyrsquos Law

S Hughes 2003

Groundwater Movement -- Darcyrsquos Law

Q = KIA -- Henry Darcy 1856 studied water flowing through porous

material His equation describes groundwater flow

Darcyrsquos experiment

bull Water is applied underpressure through end Aflows through the pipe anddischarges at end B

bull Water pressure ismeasured using piezometertubes

Hydraulic head = dh (change in height between A and B)Flow length = dL (distance between the two tubes)Hydraulic gradient (I) = dh dL

S Hughes 2003

High K materials

Groundwater MovementTable 106 in textbook (Keller 2000)

Porosity and hydraulic conductivity (rate at which water moves througha material) of selected earth materials

Hydraulic

Porosity ConductivityMaterial () (mday)

UnconsolidatedClay 45 0041Sand 35 328Gravel 25 2050Gravel and sand 20 820

RockSandstone 15 287Dense limestone or shale 5 0041Granite 1 00041

S Hughes 2003

Hydraulic conductivity = ability of material to allow water to move through itexpressed in terms of mday (distancetime) It is a function of the size andshape of particles and the size shape and connectivity of pore spaces

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 624

eol 11 1st Sem AY2011-12 91920

DNJ

Flow lines

Confining beds

WellsWater table

Millennia

Centuries

Decades

Years

Days

Dischargearea

Unconfinedaquifer

Confinedaquifers

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Years

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining bedsDecades

Years

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Centuries

Decades

Years

Days

Dischargearea

Unconfinedaquifer

Confinedaquifers

WellsWater table

Flow lines

Confining beds

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Millennia

Centuries

Decades

Years

Days

Dischargearea

WellsWater table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 724

eol 11 1st Sem AY2011-12 91920

DNJ

Effluent streams

bull Receive water emergingfrom a submerged spring or

other groundwater seepage

bull The surface of the streamdirectly relates to the watertable thus will rise and fallas the water table rises andfalls

bull Common in temperate totropical climates run yearround

Influent streams

bull May or may not be directly

connected to the water table

bull Supplement the water in the

zone of saturation producing

an upward bulge in the water

table directly underneath

bull Common in arid climates may

be temporary only present

when rainfall or flash flooding

occurs

Groundwater storage amp movement

bull Aquifer ndash permeable rock strata or sediment thattransmits groundwater freely (eg sands gravelsfractured rock)

An aquifer is a formation that allows water to be accessibleat a usable rate

bull Aquitard ndash impermeable rock strata or sedimentthat slows down or retards water movement (egclay non-fractured rock)

bull Aquiclude (aquifuge) ndash porous rock stata or

sediment with poor permeability such that itblocks groundwater movement

Unconfined

Aquifer

They are notsealed off at anypoint

Recharge canoccur anywhere

Water at wtableunder atmpressure

Must lower bucketor pump to accesswater

Unconfined aquifer ndash an aquifer whose upper limit is the water table has no confining

layers that retard vertical water movement

Confined aquifer ndash an aquifer sandwiched between two impermeable strata Confined

aquifers have non-permeable layers above and below the aquifer zone referred

to as aquitards or aquicludes

Unconfined aquifer

-Sealed off

-Transmits waterdown from RA

-Water confined inaquifer unlessdrilled

-Water underhydrostaticpressure

- Water rises wellmay flow

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 824

eol 11 1st Sem AY2011-12 91920

DNJ

Perched aquifer ndash an unconfined groundwater body supported by a

small impermeable or slowly permeable layer

Spring ndash natural flow of groundwater resulting from the intersection

of the water table with the land surface

Springs

bull Form when an aquicludeblocks the downwardmovement of

groundwater and forces itto move laterally towardsa more permeable bed orarea of less confinement

bull Dependent on rock typesand relationshipsprimary amp secondaryporosity and permeability

Porous limestone overlies an impermeable shale unit and a line

of springs occurs along the hillside where the two rock unitsmeet

Springs issue from the contact between a highly jointed lava flow

and the underlying impermeable mudstone

Springs flow from the place where a fault intersects the ground

surface

Springs

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 924

eol 11 1st Sem AY2011-12 91920

DNJ

Springs Desert Oases

Wells

bull Openings bored into the zone of saturationSuccessful andUnsuccessful Wells

Yields to wells from nonhomogeneous rock can bevariableA) wells that penetratefractures in metamorphicand igneous rocks producewater Dry wells result if nowater-bearing fractures areencounteredB) Perched water bodiesabove the main water tableare held up by aquicludes

and provide shallow sourcesof groundwater Wells thatmiss the perched water bodyand do not reach the deeperwater table are dry

Wellsbull Drawdown ndash lowering of water

table resulting from the

removal of water from a well

cone of depression

bull Hydraulic gradient ndash slope of

the water table increases with

more groundwater extraction

thereby increasing the rate of

groundwater flow into the well

Artesian wells

bull Groundwater under pressure rises above the level of the

aquiferbull Conditions for an artesian system

ndash Water must be confined to an aquifer that is inclined so that

one end can receive water

ndash Aquicludes or aquitards both above and below the aquifer

must be present to prevent the water from escaping the

pressure created on the aquifer will cause the water to rise

bull Does not always connote free-flowing surface discharge

bull Nonflowing artesian wells ndash pressure surface is below ground

level

bull Flowing artesian wells ndash pressure surface is above ground level

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1024

eol 11 1st Sem AY2011-12 91920

DNJ

Flowing or Artesian Well Development

Flowing Artesian Wells

groundwater in confined system is

under enough pressure that no well

pumping is needed

The Dakota Aquifer System

Problems with groundwater withdrawal

bull Groundwater depletion or lowering of the water

table

ndash groundwater removed from an aquifer exceeds

the amount produced (ie demand gtgt supply)

ndash caused by

bull too much demand

bull too little recharge

Lowering of the Water Table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 524

eol 11 1st Sem AY2011-12 91920

DNJ

HYDRAULIC HEAD FLUID POTENTIAL = h (length units)bull Measure of energy potential (essentially is a measure ofelevationalgravitational potential energy)

bull The driving force for groundwater flow

bull

Water flows from high to low fluid potential or hydraulic (even if thismeans it may go uphill)

bull Hydraulic head is used to determine the hydraulic gradient

Hydraulic head = the driving force that moves groundwater Thehydraulic head combines fluid pressure and gradient and can bethought of as the standing elevation that water will rise to in a wellallowed to come to equilibrium with the subsurface Groundwateralways moves from an area of higher hydraulic head to an area of lowerhydraulic head Therefore groundwater not only flows downward it canalso flow laterally or upward

Groundwater Movement

S Hughes 2003

Groundwater Flow Velocity - Darcyrsquos Law

v = K (h1-h2)lv velocity

K hydraulic conductivity

The velocity of groundwater is based on hydraulic conductivity (K)as well as the hydraulic head (I)

The equation to describe the relations between subsurface materialsand the movement of water through them is

Q = KIAQ = Discharge = volumetric flow rate volume of water flowingthrough an aquifer per unit time (m3 day)

A = Area through which the groundwater is flowing cross-sectionalarea of flow (aquifer width x thickness in m 2)

Rearrange the equation to QA = KI known as the flux (v) which isan apparent velocity

Groundwater Movement -- Darcyrsquos Law

S Hughes 2003

Groundwater Movement -- Darcyrsquos Law

Q = KIA -- Henry Darcy 1856 studied water flowing through porous

material His equation describes groundwater flow

Darcyrsquos experiment

bull Water is applied underpressure through end Aflows through the pipe anddischarges at end B

bull Water pressure ismeasured using piezometertubes

Hydraulic head = dh (change in height between A and B)Flow length = dL (distance between the two tubes)Hydraulic gradient (I) = dh dL

S Hughes 2003

High K materials

Groundwater MovementTable 106 in textbook (Keller 2000)

Porosity and hydraulic conductivity (rate at which water moves througha material) of selected earth materials

Hydraulic

Porosity ConductivityMaterial () (mday)

UnconsolidatedClay 45 0041Sand 35 328Gravel 25 2050Gravel and sand 20 820

RockSandstone 15 287Dense limestone or shale 5 0041Granite 1 00041

S Hughes 2003

Hydraulic conductivity = ability of material to allow water to move through itexpressed in terms of mday (distancetime) It is a function of the size andshape of particles and the size shape and connectivity of pore spaces

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 624

eol 11 1st Sem AY2011-12 91920

DNJ

Flow lines

Confining beds

WellsWater table

Millennia

Centuries

Decades

Years

Days

Dischargearea

Unconfinedaquifer

Confinedaquifers

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Years

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining bedsDecades

Years

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Centuries

Decades

Years

Days

Dischargearea

Unconfinedaquifer

Confinedaquifers

WellsWater table

Flow lines

Confining beds

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Millennia

Centuries

Decades

Years

Days

Dischargearea

WellsWater table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 724

eol 11 1st Sem AY2011-12 91920

DNJ

Effluent streams

bull Receive water emergingfrom a submerged spring or

other groundwater seepage

bull The surface of the streamdirectly relates to the watertable thus will rise and fallas the water table rises andfalls

bull Common in temperate totropical climates run yearround

Influent streams

bull May or may not be directly

connected to the water table

bull Supplement the water in the

zone of saturation producing

an upward bulge in the water

table directly underneath

bull Common in arid climates may

be temporary only present

when rainfall or flash flooding

occurs

Groundwater storage amp movement

bull Aquifer ndash permeable rock strata or sediment thattransmits groundwater freely (eg sands gravelsfractured rock)

An aquifer is a formation that allows water to be accessibleat a usable rate

bull Aquitard ndash impermeable rock strata or sedimentthat slows down or retards water movement (egclay non-fractured rock)

bull Aquiclude (aquifuge) ndash porous rock stata or

sediment with poor permeability such that itblocks groundwater movement

Unconfined

Aquifer

They are notsealed off at anypoint

Recharge canoccur anywhere

Water at wtableunder atmpressure

Must lower bucketor pump to accesswater

Unconfined aquifer ndash an aquifer whose upper limit is the water table has no confining

layers that retard vertical water movement

Confined aquifer ndash an aquifer sandwiched between two impermeable strata Confined

aquifers have non-permeable layers above and below the aquifer zone referred

to as aquitards or aquicludes

Unconfined aquifer

-Sealed off

-Transmits waterdown from RA

-Water confined inaquifer unlessdrilled

-Water underhydrostaticpressure

- Water rises wellmay flow

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 824

eol 11 1st Sem AY2011-12 91920

DNJ

Perched aquifer ndash an unconfined groundwater body supported by a

small impermeable or slowly permeable layer

Spring ndash natural flow of groundwater resulting from the intersection

of the water table with the land surface

Springs

bull Form when an aquicludeblocks the downwardmovement of

groundwater and forces itto move laterally towardsa more permeable bed orarea of less confinement

bull Dependent on rock typesand relationshipsprimary amp secondaryporosity and permeability

Porous limestone overlies an impermeable shale unit and a line

of springs occurs along the hillside where the two rock unitsmeet

Springs issue from the contact between a highly jointed lava flow

and the underlying impermeable mudstone

Springs flow from the place where a fault intersects the ground

surface

Springs

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 924

eol 11 1st Sem AY2011-12 91920

DNJ

Springs Desert Oases

Wells

bull Openings bored into the zone of saturationSuccessful andUnsuccessful Wells

Yields to wells from nonhomogeneous rock can bevariableA) wells that penetratefractures in metamorphicand igneous rocks producewater Dry wells result if nowater-bearing fractures areencounteredB) Perched water bodiesabove the main water tableare held up by aquicludes

and provide shallow sourcesof groundwater Wells thatmiss the perched water bodyand do not reach the deeperwater table are dry

Wellsbull Drawdown ndash lowering of water

table resulting from the

removal of water from a well

cone of depression

bull Hydraulic gradient ndash slope of

the water table increases with

more groundwater extraction

thereby increasing the rate of

groundwater flow into the well

Artesian wells

bull Groundwater under pressure rises above the level of the

aquiferbull Conditions for an artesian system

ndash Water must be confined to an aquifer that is inclined so that

one end can receive water

ndash Aquicludes or aquitards both above and below the aquifer

must be present to prevent the water from escaping the

pressure created on the aquifer will cause the water to rise

bull Does not always connote free-flowing surface discharge

bull Nonflowing artesian wells ndash pressure surface is below ground

level

bull Flowing artesian wells ndash pressure surface is above ground level

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1024

eol 11 1st Sem AY2011-12 91920

DNJ

Flowing or Artesian Well Development

Flowing Artesian Wells

groundwater in confined system is

under enough pressure that no well

pumping is needed

The Dakota Aquifer System

Problems with groundwater withdrawal

bull Groundwater depletion or lowering of the water

table

ndash groundwater removed from an aquifer exceeds

the amount produced (ie demand gtgt supply)

ndash caused by

bull too much demand

bull too little recharge

Lowering of the Water Table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 624

eol 11 1st Sem AY2011-12 91920

DNJ

Flow lines

Confining beds

WellsWater table

Millennia

Centuries

Decades

Years

Days

Dischargearea

Unconfinedaquifer

Confinedaquifers

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Years

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining bedsDecades

Years

Days

Dischargearea

WellsWater table

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Centuries

Decades

Years

Days

Dischargearea

Unconfinedaquifer

Confinedaquifers

WellsWater table

Flow lines

Confining beds

Unconfinedaquifer

Confinedaquifers

Flow lines

Confining beds

Millennia

Centuries

Decades

Years

Days

Dischargearea

WellsWater table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 724

eol 11 1st Sem AY2011-12 91920

DNJ

Effluent streams

bull Receive water emergingfrom a submerged spring or

other groundwater seepage

bull The surface of the streamdirectly relates to the watertable thus will rise and fallas the water table rises andfalls

bull Common in temperate totropical climates run yearround

Influent streams

bull May or may not be directly

connected to the water table

bull Supplement the water in the

zone of saturation producing

an upward bulge in the water

table directly underneath

bull Common in arid climates may

be temporary only present

when rainfall or flash flooding

occurs

Groundwater storage amp movement

bull Aquifer ndash permeable rock strata or sediment thattransmits groundwater freely (eg sands gravelsfractured rock)

An aquifer is a formation that allows water to be accessibleat a usable rate

bull Aquitard ndash impermeable rock strata or sedimentthat slows down or retards water movement (egclay non-fractured rock)

bull Aquiclude (aquifuge) ndash porous rock stata or

sediment with poor permeability such that itblocks groundwater movement

Unconfined

Aquifer

They are notsealed off at anypoint

Recharge canoccur anywhere

Water at wtableunder atmpressure

Must lower bucketor pump to accesswater

Unconfined aquifer ndash an aquifer whose upper limit is the water table has no confining

layers that retard vertical water movement

Confined aquifer ndash an aquifer sandwiched between two impermeable strata Confined

aquifers have non-permeable layers above and below the aquifer zone referred

to as aquitards or aquicludes

Unconfined aquifer

-Sealed off

-Transmits waterdown from RA

-Water confined inaquifer unlessdrilled

-Water underhydrostaticpressure

- Water rises wellmay flow

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 824

eol 11 1st Sem AY2011-12 91920

DNJ

Perched aquifer ndash an unconfined groundwater body supported by a

small impermeable or slowly permeable layer

Spring ndash natural flow of groundwater resulting from the intersection

of the water table with the land surface

Springs

bull Form when an aquicludeblocks the downwardmovement of

groundwater and forces itto move laterally towardsa more permeable bed orarea of less confinement

bull Dependent on rock typesand relationshipsprimary amp secondaryporosity and permeability

Porous limestone overlies an impermeable shale unit and a line

of springs occurs along the hillside where the two rock unitsmeet

Springs issue from the contact between a highly jointed lava flow

and the underlying impermeable mudstone

Springs flow from the place where a fault intersects the ground

surface

Springs

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 924

eol 11 1st Sem AY2011-12 91920

DNJ

Springs Desert Oases

Wells

bull Openings bored into the zone of saturationSuccessful andUnsuccessful Wells

Yields to wells from nonhomogeneous rock can bevariableA) wells that penetratefractures in metamorphicand igneous rocks producewater Dry wells result if nowater-bearing fractures areencounteredB) Perched water bodiesabove the main water tableare held up by aquicludes

and provide shallow sourcesof groundwater Wells thatmiss the perched water bodyand do not reach the deeperwater table are dry

Wellsbull Drawdown ndash lowering of water

table resulting from the

removal of water from a well

cone of depression

bull Hydraulic gradient ndash slope of

the water table increases with

more groundwater extraction

thereby increasing the rate of

groundwater flow into the well

Artesian wells

bull Groundwater under pressure rises above the level of the

aquiferbull Conditions for an artesian system

ndash Water must be confined to an aquifer that is inclined so that

one end can receive water

ndash Aquicludes or aquitards both above and below the aquifer

must be present to prevent the water from escaping the

pressure created on the aquifer will cause the water to rise

bull Does not always connote free-flowing surface discharge

bull Nonflowing artesian wells ndash pressure surface is below ground

level

bull Flowing artesian wells ndash pressure surface is above ground level

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1024

eol 11 1st Sem AY2011-12 91920

DNJ

Flowing or Artesian Well Development

Flowing Artesian Wells

groundwater in confined system is

under enough pressure that no well

pumping is needed

The Dakota Aquifer System

Problems with groundwater withdrawal

bull Groundwater depletion or lowering of the water

table

ndash groundwater removed from an aquifer exceeds

the amount produced (ie demand gtgt supply)

ndash caused by

bull too much demand

bull too little recharge

Lowering of the Water Table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 724

eol 11 1st Sem AY2011-12 91920

DNJ

Effluent streams

bull Receive water emergingfrom a submerged spring or

other groundwater seepage

bull The surface of the streamdirectly relates to the watertable thus will rise and fallas the water table rises andfalls

bull Common in temperate totropical climates run yearround

Influent streams

bull May or may not be directly

connected to the water table

bull Supplement the water in the

zone of saturation producing

an upward bulge in the water

table directly underneath

bull Common in arid climates may

be temporary only present

when rainfall or flash flooding

occurs

Groundwater storage amp movement

bull Aquifer ndash permeable rock strata or sediment thattransmits groundwater freely (eg sands gravelsfractured rock)

An aquifer is a formation that allows water to be accessibleat a usable rate

bull Aquitard ndash impermeable rock strata or sedimentthat slows down or retards water movement (egclay non-fractured rock)

bull Aquiclude (aquifuge) ndash porous rock stata or

sediment with poor permeability such that itblocks groundwater movement

Unconfined

Aquifer

They are notsealed off at anypoint

Recharge canoccur anywhere

Water at wtableunder atmpressure

Must lower bucketor pump to accesswater

Unconfined aquifer ndash an aquifer whose upper limit is the water table has no confining

layers that retard vertical water movement

Confined aquifer ndash an aquifer sandwiched between two impermeable strata Confined

aquifers have non-permeable layers above and below the aquifer zone referred

to as aquitards or aquicludes

Unconfined aquifer

-Sealed off

-Transmits waterdown from RA

-Water confined inaquifer unlessdrilled

-Water underhydrostaticpressure

- Water rises wellmay flow

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 824

eol 11 1st Sem AY2011-12 91920

DNJ

Perched aquifer ndash an unconfined groundwater body supported by a

small impermeable or slowly permeable layer

Spring ndash natural flow of groundwater resulting from the intersection

of the water table with the land surface

Springs

bull Form when an aquicludeblocks the downwardmovement of

groundwater and forces itto move laterally towardsa more permeable bed orarea of less confinement

bull Dependent on rock typesand relationshipsprimary amp secondaryporosity and permeability

Porous limestone overlies an impermeable shale unit and a line

of springs occurs along the hillside where the two rock unitsmeet

Springs issue from the contact between a highly jointed lava flow

and the underlying impermeable mudstone

Springs flow from the place where a fault intersects the ground

surface

Springs

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 924

eol 11 1st Sem AY2011-12 91920

DNJ

Springs Desert Oases

Wells

bull Openings bored into the zone of saturationSuccessful andUnsuccessful Wells

Yields to wells from nonhomogeneous rock can bevariableA) wells that penetratefractures in metamorphicand igneous rocks producewater Dry wells result if nowater-bearing fractures areencounteredB) Perched water bodiesabove the main water tableare held up by aquicludes

and provide shallow sourcesof groundwater Wells thatmiss the perched water bodyand do not reach the deeperwater table are dry

Wellsbull Drawdown ndash lowering of water

table resulting from the

removal of water from a well

cone of depression

bull Hydraulic gradient ndash slope of

the water table increases with

more groundwater extraction

thereby increasing the rate of

groundwater flow into the well

Artesian wells

bull Groundwater under pressure rises above the level of the

aquiferbull Conditions for an artesian system

ndash Water must be confined to an aquifer that is inclined so that

one end can receive water

ndash Aquicludes or aquitards both above and below the aquifer

must be present to prevent the water from escaping the

pressure created on the aquifer will cause the water to rise

bull Does not always connote free-flowing surface discharge

bull Nonflowing artesian wells ndash pressure surface is below ground

level

bull Flowing artesian wells ndash pressure surface is above ground level

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1024

eol 11 1st Sem AY2011-12 91920

DNJ

Flowing or Artesian Well Development

Flowing Artesian Wells

groundwater in confined system is

under enough pressure that no well

pumping is needed

The Dakota Aquifer System

Problems with groundwater withdrawal

bull Groundwater depletion or lowering of the water

table

ndash groundwater removed from an aquifer exceeds

the amount produced (ie demand gtgt supply)

ndash caused by

bull too much demand

bull too little recharge

Lowering of the Water Table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 824

eol 11 1st Sem AY2011-12 91920

DNJ

Perched aquifer ndash an unconfined groundwater body supported by a

small impermeable or slowly permeable layer

Spring ndash natural flow of groundwater resulting from the intersection

of the water table with the land surface

Springs

bull Form when an aquicludeblocks the downwardmovement of

groundwater and forces itto move laterally towardsa more permeable bed orarea of less confinement

bull Dependent on rock typesand relationshipsprimary amp secondaryporosity and permeability

Porous limestone overlies an impermeable shale unit and a line

of springs occurs along the hillside where the two rock unitsmeet

Springs issue from the contact between a highly jointed lava flow

and the underlying impermeable mudstone

Springs flow from the place where a fault intersects the ground

surface

Springs

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 924

eol 11 1st Sem AY2011-12 91920

DNJ

Springs Desert Oases

Wells

bull Openings bored into the zone of saturationSuccessful andUnsuccessful Wells

Yields to wells from nonhomogeneous rock can bevariableA) wells that penetratefractures in metamorphicand igneous rocks producewater Dry wells result if nowater-bearing fractures areencounteredB) Perched water bodiesabove the main water tableare held up by aquicludes

and provide shallow sourcesof groundwater Wells thatmiss the perched water bodyand do not reach the deeperwater table are dry

Wellsbull Drawdown ndash lowering of water

table resulting from the

removal of water from a well

cone of depression

bull Hydraulic gradient ndash slope of

the water table increases with

more groundwater extraction

thereby increasing the rate of

groundwater flow into the well

Artesian wells

bull Groundwater under pressure rises above the level of the

aquiferbull Conditions for an artesian system

ndash Water must be confined to an aquifer that is inclined so that

one end can receive water

ndash Aquicludes or aquitards both above and below the aquifer

must be present to prevent the water from escaping the

pressure created on the aquifer will cause the water to rise

bull Does not always connote free-flowing surface discharge

bull Nonflowing artesian wells ndash pressure surface is below ground

level

bull Flowing artesian wells ndash pressure surface is above ground level

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1024

eol 11 1st Sem AY2011-12 91920

DNJ

Flowing or Artesian Well Development

Flowing Artesian Wells

groundwater in confined system is

under enough pressure that no well

pumping is needed

The Dakota Aquifer System

Problems with groundwater withdrawal

bull Groundwater depletion or lowering of the water

table

ndash groundwater removed from an aquifer exceeds

the amount produced (ie demand gtgt supply)

ndash caused by

bull too much demand

bull too little recharge

Lowering of the Water Table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 924

eol 11 1st Sem AY2011-12 91920

DNJ

Springs Desert Oases

Wells

bull Openings bored into the zone of saturationSuccessful andUnsuccessful Wells

Yields to wells from nonhomogeneous rock can bevariableA) wells that penetratefractures in metamorphicand igneous rocks producewater Dry wells result if nowater-bearing fractures areencounteredB) Perched water bodiesabove the main water tableare held up by aquicludes

and provide shallow sourcesof groundwater Wells thatmiss the perched water bodyand do not reach the deeperwater table are dry

Wellsbull Drawdown ndash lowering of water

table resulting from the

removal of water from a well

cone of depression

bull Hydraulic gradient ndash slope of

the water table increases with

more groundwater extraction

thereby increasing the rate of

groundwater flow into the well

Artesian wells

bull Groundwater under pressure rises above the level of the

aquiferbull Conditions for an artesian system

ndash Water must be confined to an aquifer that is inclined so that

one end can receive water

ndash Aquicludes or aquitards both above and below the aquifer

must be present to prevent the water from escaping the

pressure created on the aquifer will cause the water to rise

bull Does not always connote free-flowing surface discharge

bull Nonflowing artesian wells ndash pressure surface is below ground

level

bull Flowing artesian wells ndash pressure surface is above ground level

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1024

eol 11 1st Sem AY2011-12 91920

DNJ

Flowing or Artesian Well Development

Flowing Artesian Wells

groundwater in confined system is

under enough pressure that no well

pumping is needed

The Dakota Aquifer System

Problems with groundwater withdrawal

bull Groundwater depletion or lowering of the water

table

ndash groundwater removed from an aquifer exceeds

the amount produced (ie demand gtgt supply)

ndash caused by

bull too much demand

bull too little recharge

Lowering of the Water Table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1024

eol 11 1st Sem AY2011-12 91920

DNJ

Flowing or Artesian Well Development

Flowing Artesian Wells

groundwater in confined system is

under enough pressure that no well

pumping is needed

The Dakota Aquifer System

Problems with groundwater withdrawal

bull Groundwater depletion or lowering of the water

table

ndash groundwater removed from an aquifer exceeds

the amount produced (ie demand gtgt supply)

ndash caused by

bull too much demand

bull too little recharge

Lowering of the Water Table

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1124

eol 11 1st Sem AY2011-12 91920

DNJ

Problems with groundwater withdrawal

bull Saltwater contamination

ndash commonly occurs in many coastal areas where there is

a direct relationship between fresh groundwater andsalt groundwater

ndash since freshwater is less dense than salt water it f loats

on the salt water and forms a large lens-shaped body

that may extend to considerable depths below sea

level

ndash excessive pumping depletes the fresh groundwater

causing salt water to rise to a height where it can be

drawn into wells contaminating the freshwater supply

Saltwater Intrusion

Before

After

Animation

Problems with groundwater withdrawal

bull Groundwater contamination due to human activities

ndash most common source of pollution is sewage

(septic tanks inadequatebroken sewer systems

barnyard wastes etc)

ndash other sources include highway salt fertilizers

pesticides plus chemicals that may leak from

pipelines storage tanks landfills and holding

ponds

Reversal of Groundwater Flow Direction Reversal of Groundwater Flow Direction

Animation 1

Animation 2

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1224

eol 11 1st Sem AY2011-12 91920

DNJ

Development of Contamination in Groundwater

Contaminant Plumes

If contaminants are soluble (completely dissolved in thewater) they move with the local groundwater flow

If contaminants are INSOLUBLE (do not dissolve or mix in the water)

Contaminant Plumes

Problems with groundwater withdrawal

bull Pore collapse

ndash because water cannot be compressed it holds thegrains of the rock or sediment apart

ndash extraction of water from pores eliminate thesupport holding the grains apart (air that replacesthe water can be compressed)

ndash grains pack more closely together permanentlydecreasing the porosity and permeability of therock

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1324

eol 11 1st Sem AY2011-12 91920

DNJ

Problems with groundwater withdrawal

bull Surface subsidence

ndash common in areas underlain by thick layers of

unconsolidated sediments

ndash as water pressure drops the weight of the

overburden is transferred to the sediment

ndash increased pressure packs the sediments tightly

together and the ground subsides

USGS scientist Joe Poland shows

the amount of ground

subsidence in the San Joaquin

Valley California between 1925

and 1977 due to fluidwithdrawal and soil

consolidation

httpwwwaegweborgimagesGeologic20Hazardssubsidence_Polandjpg

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1424

eol 11 1st Sem AY2011-12 91920

DNJ

bull In coastal areas land subsidence may even make the land surface sink

below sea level

bull The flooding in Venice Italy is due to land subsidence accompanying the

withdrawal of groundwater

bull The Leaning Tower of

Pisa (Italy) tilts because

the removal of groundwater caused its

foundation to subside

bull Land subsidence is most

severe for clay- and

organic-rich sediments

Nixa Missouri

A sinkhole collapse early morning of 13 Aug 2006 in Nixa Missouri is responsiblefor the disappearance of a garage and the Chevy Cavalier once parked inside The

sinkhole was initially estimated to be approximately 18 m in diameter and 23 m

deep

Guatemala Cit y

This 100 m-deep sinkhole

swallowed about a dozen homes on

23 Feb 2007 and is so far blamed in

the deaths of three peoplemdashtwoteenagers found floating in torrent

of sewage and their father who

was pulled from the chasm

Rainstorms and a ruptured sewer

main may have caused the

sinkhole After the collapse the

seemingly bottomless depths gave

off tremors sounds of flowing

water and the scent of sewage

httpnewsnationalgeographiccomnews200702070226-sinkhole-photohtml

Guatemala City

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1524

eol 11 1st Sem AY2011-12 91920

DNJ

Damaging effects of subsidence

bull Construction damage (buildings roads dams etc)

bull Alteration of landscape

bull Increased risk of flooding (lowered land surface)

bull Case study Pampanga Delta subsidence - initial

results of an 3-year research project funded DA-BAR

with initial funding from UP-CIDS

ndash People involved Rhodora Aparente Cherry Ringor

Nathaniel Baluda Kelvin Rodolfo Corazon Lamug

Fernando Siringan Cristina Remotigue Napoleon

Villanueva

1989

2001

Typical emerging well

Well rising outdoors

0

Legend

Roads

N

10 kmsLineaments

2219

38gt4

27

Benchmarks (DPWH 2001)

Emerging wells (cmyr)

406 cmyr

07110

33

176 cmyr3213

05 cmyr

23 cmyr

18 cmyr

0

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1624

eol 11 1st Sem AY2011-12 91920

DNJ

At Manilarsquos South Harbor mean sea level rose at about 2millimeters per year from 1902 to the early 1960rsquos

lt20 million litersper day (MLD)

250MLD

725

MLD

778 MLD

then started rising ten times as fast WHY

Global warming

Groundwater withdrawal

Another consequenceof population growth

Loosely packed sand

When wateris removedgrains crowdtogether alittle moreclosely

Volume issomewhat

reduced soland sinks alittle

But sand cannot compactvery muchFreshly

deposited claycontains muchmore water

and canshrink muchmore

Our delta sediments are very clayey

Subsidence from water withdrawal

Other East Asian Coastal Cities Sinkingfrom Excessive Groundwater Usage

SUBSIDENCELOCATION PERIOD Meters cmyear

Tokyo 1918-87 45 65Japan

Tokyo

Osaka 1934-68 28 82Japan

OsakaShanghai 1921-65 263 6China

Shanghai

Yun-Lin 1989-97 066 825Taiwan (Fishpond area)

Yun-Lin

Hanoi 1988-93 01-03 2-6Vietnam

Hanoi

Manila Bay 1964-2002 1 25

Manila

Bangkok 1980-90 05-1 5-10Thailand

Bangkok

Jakarta 1991-99 03-08 4-10Indonesia

Jakarta

Some other regions of subsidence from over-pumping of ground water

SUBSIDENCELOCATION PERIOD Meters cmyear

London England 1865-1995 065 05

Venice Italy 1952-69 0014 08-17

Nile Delta Egypt 1985-2000 008 05

Sta Clara Valley Calif 1920-67 40 85

Houston Texas 1943-73 23 74

New Orleans LA 1924-78 20 37

Mexico City Mexico 1970-73 015 50

Latrobe Valley Austral 1961-78 16 94

Geologic work of groundwater

bull Groundwater dissolves rock

ndash Groundwater is often mildly acidic

bull Contains weak carbonic acid

bull Forms when rainwater dissolves carbon dioxide

from the air and from decaying plants

ndash Caverns

bull Most caverns are created by acidic

groundwater dissolving soluble rock at or just

below the surface in the zone of saturation

Effects of Ground-Water Actionbull caves (or caverns) naturally formed underground

chamber

bull most caves develop when slightly acidic groundwater dissolves limestone along joints and

bedding planes opening up cavern systems as

calcite is carried away in solution

bull most caves probably are formed by ground water

circulating below the water table

H2O + CO2 + CaCO3 Ca++ + 2HCO3-

water carbondioxide

calcite inlimestone

calciumion

bicarbonateion

development of caves (solution)

development of flowstone and dripstone (precipitation)

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1724

eol 11 1st Sem AY2011-12 91920

DNJ

Geologic work of groundwater

bull Features found within caverns

ndash Composed of dripstone (travertine)

ndash Calcite deposited as dripping water evaporates

ndash Collectively they are called speleothems

ndash Includes stalactites (hanging from the ceiling)

and stalagmites (form on the floor of a cavern)

Chemical Weathering of Carbonates

bull Carbonic acid dissolves the calcite in limestoneliberating CO2 and dissolved Ca2+

bull Carbonates exposed to

rain continuously dissolve

bull This dissolution results

in caverns and karst

topography

bull stalactites icicle-like pendants of dripstone hanging from

cave ceilings generally slender and are commonly aligned

along cracks in the ceiling which act as conduits for

ground water

bull stalagmites cone-shaped masses of drip-stone formed on

cave floors generally directly below stalactites

Water moves along fractures and bedding planes inlimestone dissolving the limestone to form cavesbelow the water table

Falling water table allows cave system now greatlyenlarged to fill with air Calcite precipitation formsstalactites stalagmites and columns above thewater table

Catastrophic Subsidence Caves

Collapse intocaverns

Caverns producedby dissolution of limestone by acidicwaters

Acid produced when CO2 dissolves in water (carbonic acid)

Rock dissolves below water table

Dropping water table leaves behind caverns

Formation of Sinkholes

Weakened caveroofs collapse

Often due topumping of groundwater(water helpssupportoverlying rock)

Over 4000 sinkholes have formed since1900 in Alabama alone

Sinkholes

Winter Park Florida sinkhole (100m across x 34 m deep) formed1981

ldquoDecember giantrdquo sinkhole Alabama (130 m long x 46m

deep) formed 1972

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1824

eol 11 1st Sem AY2011-12 91920

DNJ

Original artwork by Gary Hincks

bull Composed of dripstone (travertine) calcite deposited as

dripping water evaporates

bull Collectively they are called speleothems

bull Stalactites (ceiling) and stalagmites (floor)

Cavern FeaturesldquoSoda strawsrdquo in Carlsbad Caverns National Park

Kartchner Caverns Arizona

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1924

eol 11 1st Sem AY2011-12 91920

DNJ

Speleothems in Carlsbad Caverns National Park Geologic work of groundwater

bull Karst topography

ndash Landscapes that to a large extent have been shapedby the dissolving power of groundwater

ndash Some common features include

bull Irregular terrain

bull Sinkhole or sinks (formed by groundwater slowlydissolving the bedrock often accompanied bycollapse)

bull Striking lack of surface drainage (streams)

bull Caves and caverns

bull Tower karst

Karst topography

bull an area with many sinkholes and with cave

systems beneath the land surface

Karst topography is marked by underground cav es and numerous surface sinkholes A major river maycross the region but small surface streams generally disappear down sinkholes

Karst Sinkholes and Subsidence

Burnham

UP

MGB 200x

Subsidence Due to Karst

Natural developmentof sinkholes andunderground streamsin limestone areas is

a major factor in thesubsidence of certainareas of Baguio Cityincluding

Crystal CaveDominicanIrisanLourdes

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2024

eol 11 1st Sem AY2011-12 91920

DNJ

Ground subsidence in Crystal cave

(MGB 2006)

Satellite View mdash

Karst

Topography

Source Photograph copy NASA

Karstic

Area

Tower Karst

Southeastern China

Luoping Yunnan province China

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2124

eol 11 1st Sem AY2011-12 91920

DNJ

Arecibo Radio-telescope Puerto Rico

Restificar et al (2006)Protection of Karst in thePhilippinesActa

Carsologica 35 1 121 ndash

130

Restificar et al (2006) Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Restificaret al (2006)Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Chocolate Hills Bohol

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1324

eol 11 1st Sem AY2011-12 91920

DNJ

Problems with groundwater withdrawal

bull Surface subsidence

ndash common in areas underlain by thick layers of

unconsolidated sediments

ndash as water pressure drops the weight of the

overburden is transferred to the sediment

ndash increased pressure packs the sediments tightly

together and the ground subsides

USGS scientist Joe Poland shows

the amount of ground

subsidence in the San Joaquin

Valley California between 1925

and 1977 due to fluidwithdrawal and soil

consolidation

httpwwwaegweborgimagesGeologic20Hazardssubsidence_Polandjpg

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1424

eol 11 1st Sem AY2011-12 91920

DNJ

bull In coastal areas land subsidence may even make the land surface sink

below sea level

bull The flooding in Venice Italy is due to land subsidence accompanying the

withdrawal of groundwater

bull The Leaning Tower of

Pisa (Italy) tilts because

the removal of groundwater caused its

foundation to subside

bull Land subsidence is most

severe for clay- and

organic-rich sediments

Nixa Missouri

A sinkhole collapse early morning of 13 Aug 2006 in Nixa Missouri is responsiblefor the disappearance of a garage and the Chevy Cavalier once parked inside The

sinkhole was initially estimated to be approximately 18 m in diameter and 23 m

deep

Guatemala Cit y

This 100 m-deep sinkhole

swallowed about a dozen homes on

23 Feb 2007 and is so far blamed in

the deaths of three peoplemdashtwoteenagers found floating in torrent

of sewage and their father who

was pulled from the chasm

Rainstorms and a ruptured sewer

main may have caused the

sinkhole After the collapse the

seemingly bottomless depths gave

off tremors sounds of flowing

water and the scent of sewage

httpnewsnationalgeographiccomnews200702070226-sinkhole-photohtml

Guatemala City

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1524

eol 11 1st Sem AY2011-12 91920

DNJ

Damaging effects of subsidence

bull Construction damage (buildings roads dams etc)

bull Alteration of landscape

bull Increased risk of flooding (lowered land surface)

bull Case study Pampanga Delta subsidence - initial

results of an 3-year research project funded DA-BAR

with initial funding from UP-CIDS

ndash People involved Rhodora Aparente Cherry Ringor

Nathaniel Baluda Kelvin Rodolfo Corazon Lamug

Fernando Siringan Cristina Remotigue Napoleon

Villanueva

1989

2001

Typical emerging well

Well rising outdoors

0

Legend

Roads

N

10 kmsLineaments

2219

38gt4

27

Benchmarks (DPWH 2001)

Emerging wells (cmyr)

406 cmyr

07110

33

176 cmyr3213

05 cmyr

23 cmyr

18 cmyr

0

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1624

eol 11 1st Sem AY2011-12 91920

DNJ

At Manilarsquos South Harbor mean sea level rose at about 2millimeters per year from 1902 to the early 1960rsquos

lt20 million litersper day (MLD)

250MLD

725

MLD

778 MLD

then started rising ten times as fast WHY

Global warming

Groundwater withdrawal

Another consequenceof population growth

Loosely packed sand

When wateris removedgrains crowdtogether alittle moreclosely

Volume issomewhat

reduced soland sinks alittle

But sand cannot compactvery muchFreshly

deposited claycontains muchmore water

and canshrink muchmore

Our delta sediments are very clayey

Subsidence from water withdrawal

Other East Asian Coastal Cities Sinkingfrom Excessive Groundwater Usage

SUBSIDENCELOCATION PERIOD Meters cmyear

Tokyo 1918-87 45 65Japan

Tokyo

Osaka 1934-68 28 82Japan

OsakaShanghai 1921-65 263 6China

Shanghai

Yun-Lin 1989-97 066 825Taiwan (Fishpond area)

Yun-Lin

Hanoi 1988-93 01-03 2-6Vietnam

Hanoi

Manila Bay 1964-2002 1 25

Manila

Bangkok 1980-90 05-1 5-10Thailand

Bangkok

Jakarta 1991-99 03-08 4-10Indonesia

Jakarta

Some other regions of subsidence from over-pumping of ground water

SUBSIDENCELOCATION PERIOD Meters cmyear

London England 1865-1995 065 05

Venice Italy 1952-69 0014 08-17

Nile Delta Egypt 1985-2000 008 05

Sta Clara Valley Calif 1920-67 40 85

Houston Texas 1943-73 23 74

New Orleans LA 1924-78 20 37

Mexico City Mexico 1970-73 015 50

Latrobe Valley Austral 1961-78 16 94

Geologic work of groundwater

bull Groundwater dissolves rock

ndash Groundwater is often mildly acidic

bull Contains weak carbonic acid

bull Forms when rainwater dissolves carbon dioxide

from the air and from decaying plants

ndash Caverns

bull Most caverns are created by acidic

groundwater dissolving soluble rock at or just

below the surface in the zone of saturation

Effects of Ground-Water Actionbull caves (or caverns) naturally formed underground

chamber

bull most caves develop when slightly acidic groundwater dissolves limestone along joints and

bedding planes opening up cavern systems as

calcite is carried away in solution

bull most caves probably are formed by ground water

circulating below the water table

H2O + CO2 + CaCO3 Ca++ + 2HCO3-

water carbondioxide

calcite inlimestone

calciumion

bicarbonateion

development of caves (solution)

development of flowstone and dripstone (precipitation)

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1724

eol 11 1st Sem AY2011-12 91920

DNJ

Geologic work of groundwater

bull Features found within caverns

ndash Composed of dripstone (travertine)

ndash Calcite deposited as dripping water evaporates

ndash Collectively they are called speleothems

ndash Includes stalactites (hanging from the ceiling)

and stalagmites (form on the floor of a cavern)

Chemical Weathering of Carbonates

bull Carbonic acid dissolves the calcite in limestoneliberating CO2 and dissolved Ca2+

bull Carbonates exposed to

rain continuously dissolve

bull This dissolution results

in caverns and karst

topography

bull stalactites icicle-like pendants of dripstone hanging from

cave ceilings generally slender and are commonly aligned

along cracks in the ceiling which act as conduits for

ground water

bull stalagmites cone-shaped masses of drip-stone formed on

cave floors generally directly below stalactites

Water moves along fractures and bedding planes inlimestone dissolving the limestone to form cavesbelow the water table

Falling water table allows cave system now greatlyenlarged to fill with air Calcite precipitation formsstalactites stalagmites and columns above thewater table

Catastrophic Subsidence Caves

Collapse intocaverns

Caverns producedby dissolution of limestone by acidicwaters

Acid produced when CO2 dissolves in water (carbonic acid)

Rock dissolves below water table

Dropping water table leaves behind caverns

Formation of Sinkholes

Weakened caveroofs collapse

Often due topumping of groundwater(water helpssupportoverlying rock)

Over 4000 sinkholes have formed since1900 in Alabama alone

Sinkholes

Winter Park Florida sinkhole (100m across x 34 m deep) formed1981

ldquoDecember giantrdquo sinkhole Alabama (130 m long x 46m

deep) formed 1972

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1824

eol 11 1st Sem AY2011-12 91920

DNJ

Original artwork by Gary Hincks

bull Composed of dripstone (travertine) calcite deposited as

dripping water evaporates

bull Collectively they are called speleothems

bull Stalactites (ceiling) and stalagmites (floor)

Cavern FeaturesldquoSoda strawsrdquo in Carlsbad Caverns National Park

Kartchner Caverns Arizona

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1924

eol 11 1st Sem AY2011-12 91920

DNJ

Speleothems in Carlsbad Caverns National Park Geologic work of groundwater

bull Karst topography

ndash Landscapes that to a large extent have been shapedby the dissolving power of groundwater

ndash Some common features include

bull Irregular terrain

bull Sinkhole or sinks (formed by groundwater slowlydissolving the bedrock often accompanied bycollapse)

bull Striking lack of surface drainage (streams)

bull Caves and caverns

bull Tower karst

Karst topography

bull an area with many sinkholes and with cave

systems beneath the land surface

Karst topography is marked by underground cav es and numerous surface sinkholes A major river maycross the region but small surface streams generally disappear down sinkholes

Karst Sinkholes and Subsidence

Burnham

UP

MGB 200x

Subsidence Due to Karst

Natural developmentof sinkholes andunderground streamsin limestone areas is

a major factor in thesubsidence of certainareas of Baguio Cityincluding

Crystal CaveDominicanIrisanLourdes

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2024

eol 11 1st Sem AY2011-12 91920

DNJ

Ground subsidence in Crystal cave

(MGB 2006)

Satellite View mdash

Karst

Topography

Source Photograph copy NASA

Karstic

Area

Tower Karst

Southeastern China

Luoping Yunnan province China

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2124

eol 11 1st Sem AY2011-12 91920

DNJ

Arecibo Radio-telescope Puerto Rico

Restificar et al (2006)Protection of Karst in thePhilippinesActa

Carsologica 35 1 121 ndash

130

Restificar et al (2006) Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Restificaret al (2006)Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Chocolate Hills Bohol

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1424

eol 11 1st Sem AY2011-12 91920

DNJ

bull In coastal areas land subsidence may even make the land surface sink

below sea level

bull The flooding in Venice Italy is due to land subsidence accompanying the

withdrawal of groundwater

bull The Leaning Tower of

Pisa (Italy) tilts because

the removal of groundwater caused its

foundation to subside

bull Land subsidence is most

severe for clay- and

organic-rich sediments

Nixa Missouri

A sinkhole collapse early morning of 13 Aug 2006 in Nixa Missouri is responsiblefor the disappearance of a garage and the Chevy Cavalier once parked inside The

sinkhole was initially estimated to be approximately 18 m in diameter and 23 m

deep

Guatemala Cit y

This 100 m-deep sinkhole

swallowed about a dozen homes on

23 Feb 2007 and is so far blamed in

the deaths of three peoplemdashtwoteenagers found floating in torrent

of sewage and their father who

was pulled from the chasm

Rainstorms and a ruptured sewer

main may have caused the

sinkhole After the collapse the

seemingly bottomless depths gave

off tremors sounds of flowing

water and the scent of sewage

httpnewsnationalgeographiccomnews200702070226-sinkhole-photohtml

Guatemala City

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1524

eol 11 1st Sem AY2011-12 91920

DNJ

Damaging effects of subsidence

bull Construction damage (buildings roads dams etc)

bull Alteration of landscape

bull Increased risk of flooding (lowered land surface)

bull Case study Pampanga Delta subsidence - initial

results of an 3-year research project funded DA-BAR

with initial funding from UP-CIDS

ndash People involved Rhodora Aparente Cherry Ringor

Nathaniel Baluda Kelvin Rodolfo Corazon Lamug

Fernando Siringan Cristina Remotigue Napoleon

Villanueva

1989

2001

Typical emerging well

Well rising outdoors

0

Legend

Roads

N

10 kmsLineaments

2219

38gt4

27

Benchmarks (DPWH 2001)

Emerging wells (cmyr)

406 cmyr

07110

33

176 cmyr3213

05 cmyr

23 cmyr

18 cmyr

0

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1624

eol 11 1st Sem AY2011-12 91920

DNJ

At Manilarsquos South Harbor mean sea level rose at about 2millimeters per year from 1902 to the early 1960rsquos

lt20 million litersper day (MLD)

250MLD

725

MLD

778 MLD

then started rising ten times as fast WHY

Global warming

Groundwater withdrawal

Another consequenceof population growth

Loosely packed sand

When wateris removedgrains crowdtogether alittle moreclosely

Volume issomewhat

reduced soland sinks alittle

But sand cannot compactvery muchFreshly

deposited claycontains muchmore water

and canshrink muchmore

Our delta sediments are very clayey

Subsidence from water withdrawal

Other East Asian Coastal Cities Sinkingfrom Excessive Groundwater Usage

SUBSIDENCELOCATION PERIOD Meters cmyear

Tokyo 1918-87 45 65Japan

Tokyo

Osaka 1934-68 28 82Japan

OsakaShanghai 1921-65 263 6China

Shanghai

Yun-Lin 1989-97 066 825Taiwan (Fishpond area)

Yun-Lin

Hanoi 1988-93 01-03 2-6Vietnam

Hanoi

Manila Bay 1964-2002 1 25

Manila

Bangkok 1980-90 05-1 5-10Thailand

Bangkok

Jakarta 1991-99 03-08 4-10Indonesia

Jakarta

Some other regions of subsidence from over-pumping of ground water

SUBSIDENCELOCATION PERIOD Meters cmyear

London England 1865-1995 065 05

Venice Italy 1952-69 0014 08-17

Nile Delta Egypt 1985-2000 008 05

Sta Clara Valley Calif 1920-67 40 85

Houston Texas 1943-73 23 74

New Orleans LA 1924-78 20 37

Mexico City Mexico 1970-73 015 50

Latrobe Valley Austral 1961-78 16 94

Geologic work of groundwater

bull Groundwater dissolves rock

ndash Groundwater is often mildly acidic

bull Contains weak carbonic acid

bull Forms when rainwater dissolves carbon dioxide

from the air and from decaying plants

ndash Caverns

bull Most caverns are created by acidic

groundwater dissolving soluble rock at or just

below the surface in the zone of saturation

Effects of Ground-Water Actionbull caves (or caverns) naturally formed underground

chamber

bull most caves develop when slightly acidic groundwater dissolves limestone along joints and

bedding planes opening up cavern systems as

calcite is carried away in solution

bull most caves probably are formed by ground water

circulating below the water table

H2O + CO2 + CaCO3 Ca++ + 2HCO3-

water carbondioxide

calcite inlimestone

calciumion

bicarbonateion

development of caves (solution)

development of flowstone and dripstone (precipitation)

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1724

eol 11 1st Sem AY2011-12 91920

DNJ

Geologic work of groundwater

bull Features found within caverns

ndash Composed of dripstone (travertine)

ndash Calcite deposited as dripping water evaporates

ndash Collectively they are called speleothems

ndash Includes stalactites (hanging from the ceiling)

and stalagmites (form on the floor of a cavern)

Chemical Weathering of Carbonates

bull Carbonic acid dissolves the calcite in limestoneliberating CO2 and dissolved Ca2+

bull Carbonates exposed to

rain continuously dissolve

bull This dissolution results

in caverns and karst

topography

bull stalactites icicle-like pendants of dripstone hanging from

cave ceilings generally slender and are commonly aligned

along cracks in the ceiling which act as conduits for

ground water

bull stalagmites cone-shaped masses of drip-stone formed on

cave floors generally directly below stalactites

Water moves along fractures and bedding planes inlimestone dissolving the limestone to form cavesbelow the water table

Falling water table allows cave system now greatlyenlarged to fill with air Calcite precipitation formsstalactites stalagmites and columns above thewater table

Catastrophic Subsidence Caves

Collapse intocaverns

Caverns producedby dissolution of limestone by acidicwaters

Acid produced when CO2 dissolves in water (carbonic acid)

Rock dissolves below water table

Dropping water table leaves behind caverns

Formation of Sinkholes

Weakened caveroofs collapse

Often due topumping of groundwater(water helpssupportoverlying rock)

Over 4000 sinkholes have formed since1900 in Alabama alone

Sinkholes

Winter Park Florida sinkhole (100m across x 34 m deep) formed1981

ldquoDecember giantrdquo sinkhole Alabama (130 m long x 46m

deep) formed 1972

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1824

eol 11 1st Sem AY2011-12 91920

DNJ

Original artwork by Gary Hincks

bull Composed of dripstone (travertine) calcite deposited as

dripping water evaporates

bull Collectively they are called speleothems

bull Stalactites (ceiling) and stalagmites (floor)

Cavern FeaturesldquoSoda strawsrdquo in Carlsbad Caverns National Park

Kartchner Caverns Arizona

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1924

eol 11 1st Sem AY2011-12 91920

DNJ

Speleothems in Carlsbad Caverns National Park Geologic work of groundwater

bull Karst topography

ndash Landscapes that to a large extent have been shapedby the dissolving power of groundwater

ndash Some common features include

bull Irregular terrain

bull Sinkhole or sinks (formed by groundwater slowlydissolving the bedrock often accompanied bycollapse)

bull Striking lack of surface drainage (streams)

bull Caves and caverns

bull Tower karst

Karst topography

bull an area with many sinkholes and with cave

systems beneath the land surface

Karst topography is marked by underground cav es and numerous surface sinkholes A major river maycross the region but small surface streams generally disappear down sinkholes

Karst Sinkholes and Subsidence

Burnham

UP

MGB 200x

Subsidence Due to Karst

Natural developmentof sinkholes andunderground streamsin limestone areas is

a major factor in thesubsidence of certainareas of Baguio Cityincluding

Crystal CaveDominicanIrisanLourdes

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2024

eol 11 1st Sem AY2011-12 91920

DNJ

Ground subsidence in Crystal cave

(MGB 2006)

Satellite View mdash

Karst

Topography

Source Photograph copy NASA

Karstic

Area

Tower Karst

Southeastern China

Luoping Yunnan province China

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2124

eol 11 1st Sem AY2011-12 91920

DNJ

Arecibo Radio-telescope Puerto Rico

Restificar et al (2006)Protection of Karst in thePhilippinesActa

Carsologica 35 1 121 ndash

130

Restificar et al (2006) Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Restificaret al (2006)Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Chocolate Hills Bohol

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1524

eol 11 1st Sem AY2011-12 91920

DNJ

Damaging effects of subsidence

bull Construction damage (buildings roads dams etc)

bull Alteration of landscape

bull Increased risk of flooding (lowered land surface)

bull Case study Pampanga Delta subsidence - initial

results of an 3-year research project funded DA-BAR

with initial funding from UP-CIDS

ndash People involved Rhodora Aparente Cherry Ringor

Nathaniel Baluda Kelvin Rodolfo Corazon Lamug

Fernando Siringan Cristina Remotigue Napoleon

Villanueva

1989

2001

Typical emerging well

Well rising outdoors

0

Legend

Roads

N

10 kmsLineaments

2219

38gt4

27

Benchmarks (DPWH 2001)

Emerging wells (cmyr)

406 cmyr

07110

33

176 cmyr3213

05 cmyr

23 cmyr

18 cmyr

0

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1624

eol 11 1st Sem AY2011-12 91920

DNJ

At Manilarsquos South Harbor mean sea level rose at about 2millimeters per year from 1902 to the early 1960rsquos

lt20 million litersper day (MLD)

250MLD

725

MLD

778 MLD

then started rising ten times as fast WHY

Global warming

Groundwater withdrawal

Another consequenceof population growth

Loosely packed sand

When wateris removedgrains crowdtogether alittle moreclosely

Volume issomewhat

reduced soland sinks alittle

But sand cannot compactvery muchFreshly

deposited claycontains muchmore water

and canshrink muchmore

Our delta sediments are very clayey

Subsidence from water withdrawal

Other East Asian Coastal Cities Sinkingfrom Excessive Groundwater Usage

SUBSIDENCELOCATION PERIOD Meters cmyear

Tokyo 1918-87 45 65Japan

Tokyo

Osaka 1934-68 28 82Japan

OsakaShanghai 1921-65 263 6China

Shanghai

Yun-Lin 1989-97 066 825Taiwan (Fishpond area)

Yun-Lin

Hanoi 1988-93 01-03 2-6Vietnam

Hanoi

Manila Bay 1964-2002 1 25

Manila

Bangkok 1980-90 05-1 5-10Thailand

Bangkok

Jakarta 1991-99 03-08 4-10Indonesia

Jakarta

Some other regions of subsidence from over-pumping of ground water

SUBSIDENCELOCATION PERIOD Meters cmyear

London England 1865-1995 065 05

Venice Italy 1952-69 0014 08-17

Nile Delta Egypt 1985-2000 008 05

Sta Clara Valley Calif 1920-67 40 85

Houston Texas 1943-73 23 74

New Orleans LA 1924-78 20 37

Mexico City Mexico 1970-73 015 50

Latrobe Valley Austral 1961-78 16 94

Geologic work of groundwater

bull Groundwater dissolves rock

ndash Groundwater is often mildly acidic

bull Contains weak carbonic acid

bull Forms when rainwater dissolves carbon dioxide

from the air and from decaying plants

ndash Caverns

bull Most caverns are created by acidic

groundwater dissolving soluble rock at or just

below the surface in the zone of saturation

Effects of Ground-Water Actionbull caves (or caverns) naturally formed underground

chamber

bull most caves develop when slightly acidic groundwater dissolves limestone along joints and

bedding planes opening up cavern systems as

calcite is carried away in solution

bull most caves probably are formed by ground water

circulating below the water table

H2O + CO2 + CaCO3 Ca++ + 2HCO3-

water carbondioxide

calcite inlimestone

calciumion

bicarbonateion

development of caves (solution)

development of flowstone and dripstone (precipitation)

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1724

eol 11 1st Sem AY2011-12 91920

DNJ

Geologic work of groundwater

bull Features found within caverns

ndash Composed of dripstone (travertine)

ndash Calcite deposited as dripping water evaporates

ndash Collectively they are called speleothems

ndash Includes stalactites (hanging from the ceiling)

and stalagmites (form on the floor of a cavern)

Chemical Weathering of Carbonates

bull Carbonic acid dissolves the calcite in limestoneliberating CO2 and dissolved Ca2+

bull Carbonates exposed to

rain continuously dissolve

bull This dissolution results

in caverns and karst

topography

bull stalactites icicle-like pendants of dripstone hanging from

cave ceilings generally slender and are commonly aligned

along cracks in the ceiling which act as conduits for

ground water

bull stalagmites cone-shaped masses of drip-stone formed on

cave floors generally directly below stalactites

Water moves along fractures and bedding planes inlimestone dissolving the limestone to form cavesbelow the water table

Falling water table allows cave system now greatlyenlarged to fill with air Calcite precipitation formsstalactites stalagmites and columns above thewater table

Catastrophic Subsidence Caves

Collapse intocaverns

Caverns producedby dissolution of limestone by acidicwaters

Acid produced when CO2 dissolves in water (carbonic acid)

Rock dissolves below water table

Dropping water table leaves behind caverns

Formation of Sinkholes

Weakened caveroofs collapse

Often due topumping of groundwater(water helpssupportoverlying rock)

Over 4000 sinkholes have formed since1900 in Alabama alone

Sinkholes

Winter Park Florida sinkhole (100m across x 34 m deep) formed1981

ldquoDecember giantrdquo sinkhole Alabama (130 m long x 46m

deep) formed 1972

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1824

eol 11 1st Sem AY2011-12 91920

DNJ

Original artwork by Gary Hincks

bull Composed of dripstone (travertine) calcite deposited as

dripping water evaporates

bull Collectively they are called speleothems

bull Stalactites (ceiling) and stalagmites (floor)

Cavern FeaturesldquoSoda strawsrdquo in Carlsbad Caverns National Park

Kartchner Caverns Arizona

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1924

eol 11 1st Sem AY2011-12 91920

DNJ

Speleothems in Carlsbad Caverns National Park Geologic work of groundwater

bull Karst topography

ndash Landscapes that to a large extent have been shapedby the dissolving power of groundwater

ndash Some common features include

bull Irregular terrain

bull Sinkhole or sinks (formed by groundwater slowlydissolving the bedrock often accompanied bycollapse)

bull Striking lack of surface drainage (streams)

bull Caves and caverns

bull Tower karst

Karst topography

bull an area with many sinkholes and with cave

systems beneath the land surface

Karst topography is marked by underground cav es and numerous surface sinkholes A major river maycross the region but small surface streams generally disappear down sinkholes

Karst Sinkholes and Subsidence

Burnham

UP

MGB 200x

Subsidence Due to Karst

Natural developmentof sinkholes andunderground streamsin limestone areas is

a major factor in thesubsidence of certainareas of Baguio Cityincluding

Crystal CaveDominicanIrisanLourdes

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2024

eol 11 1st Sem AY2011-12 91920

DNJ

Ground subsidence in Crystal cave

(MGB 2006)

Satellite View mdash

Karst

Topography

Source Photograph copy NASA

Karstic

Area

Tower Karst

Southeastern China

Luoping Yunnan province China

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2124

eol 11 1st Sem AY2011-12 91920

DNJ

Arecibo Radio-telescope Puerto Rico

Restificar et al (2006)Protection of Karst in thePhilippinesActa

Carsologica 35 1 121 ndash

130

Restificar et al (2006) Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Restificaret al (2006)Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Chocolate Hills Bohol

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1624

eol 11 1st Sem AY2011-12 91920

DNJ

At Manilarsquos South Harbor mean sea level rose at about 2millimeters per year from 1902 to the early 1960rsquos

lt20 million litersper day (MLD)

250MLD

725

MLD

778 MLD

then started rising ten times as fast WHY

Global warming

Groundwater withdrawal

Another consequenceof population growth

Loosely packed sand

When wateris removedgrains crowdtogether alittle moreclosely

Volume issomewhat

reduced soland sinks alittle

But sand cannot compactvery muchFreshly

deposited claycontains muchmore water

and canshrink muchmore

Our delta sediments are very clayey

Subsidence from water withdrawal

Other East Asian Coastal Cities Sinkingfrom Excessive Groundwater Usage

SUBSIDENCELOCATION PERIOD Meters cmyear

Tokyo 1918-87 45 65Japan

Tokyo

Osaka 1934-68 28 82Japan

OsakaShanghai 1921-65 263 6China

Shanghai

Yun-Lin 1989-97 066 825Taiwan (Fishpond area)

Yun-Lin

Hanoi 1988-93 01-03 2-6Vietnam

Hanoi

Manila Bay 1964-2002 1 25

Manila

Bangkok 1980-90 05-1 5-10Thailand

Bangkok

Jakarta 1991-99 03-08 4-10Indonesia

Jakarta

Some other regions of subsidence from over-pumping of ground water

SUBSIDENCELOCATION PERIOD Meters cmyear

London England 1865-1995 065 05

Venice Italy 1952-69 0014 08-17

Nile Delta Egypt 1985-2000 008 05

Sta Clara Valley Calif 1920-67 40 85

Houston Texas 1943-73 23 74

New Orleans LA 1924-78 20 37

Mexico City Mexico 1970-73 015 50

Latrobe Valley Austral 1961-78 16 94

Geologic work of groundwater

bull Groundwater dissolves rock

ndash Groundwater is often mildly acidic

bull Contains weak carbonic acid

bull Forms when rainwater dissolves carbon dioxide

from the air and from decaying plants

ndash Caverns

bull Most caverns are created by acidic

groundwater dissolving soluble rock at or just

below the surface in the zone of saturation

Effects of Ground-Water Actionbull caves (or caverns) naturally formed underground

chamber

bull most caves develop when slightly acidic groundwater dissolves limestone along joints and

bedding planes opening up cavern systems as

calcite is carried away in solution

bull most caves probably are formed by ground water

circulating below the water table

H2O + CO2 + CaCO3 Ca++ + 2HCO3-

water carbondioxide

calcite inlimestone

calciumion

bicarbonateion

development of caves (solution)

development of flowstone and dripstone (precipitation)

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1724

eol 11 1st Sem AY2011-12 91920

DNJ

Geologic work of groundwater

bull Features found within caverns

ndash Composed of dripstone (travertine)

ndash Calcite deposited as dripping water evaporates

ndash Collectively they are called speleothems

ndash Includes stalactites (hanging from the ceiling)

and stalagmites (form on the floor of a cavern)

Chemical Weathering of Carbonates

bull Carbonic acid dissolves the calcite in limestoneliberating CO2 and dissolved Ca2+

bull Carbonates exposed to

rain continuously dissolve

bull This dissolution results

in caverns and karst

topography

bull stalactites icicle-like pendants of dripstone hanging from

cave ceilings generally slender and are commonly aligned

along cracks in the ceiling which act as conduits for

ground water

bull stalagmites cone-shaped masses of drip-stone formed on

cave floors generally directly below stalactites

Water moves along fractures and bedding planes inlimestone dissolving the limestone to form cavesbelow the water table

Falling water table allows cave system now greatlyenlarged to fill with air Calcite precipitation formsstalactites stalagmites and columns above thewater table

Catastrophic Subsidence Caves

Collapse intocaverns

Caverns producedby dissolution of limestone by acidicwaters

Acid produced when CO2 dissolves in water (carbonic acid)

Rock dissolves below water table

Dropping water table leaves behind caverns

Formation of Sinkholes

Weakened caveroofs collapse

Often due topumping of groundwater(water helpssupportoverlying rock)

Over 4000 sinkholes have formed since1900 in Alabama alone

Sinkholes

Winter Park Florida sinkhole (100m across x 34 m deep) formed1981

ldquoDecember giantrdquo sinkhole Alabama (130 m long x 46m

deep) formed 1972

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1824

eol 11 1st Sem AY2011-12 91920

DNJ

Original artwork by Gary Hincks

bull Composed of dripstone (travertine) calcite deposited as

dripping water evaporates

bull Collectively they are called speleothems

bull Stalactites (ceiling) and stalagmites (floor)

Cavern FeaturesldquoSoda strawsrdquo in Carlsbad Caverns National Park

Kartchner Caverns Arizona

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1924

eol 11 1st Sem AY2011-12 91920

DNJ

Speleothems in Carlsbad Caverns National Park Geologic work of groundwater

bull Karst topography

ndash Landscapes that to a large extent have been shapedby the dissolving power of groundwater

ndash Some common features include

bull Irregular terrain

bull Sinkhole or sinks (formed by groundwater slowlydissolving the bedrock often accompanied bycollapse)

bull Striking lack of surface drainage (streams)

bull Caves and caverns

bull Tower karst

Karst topography

bull an area with many sinkholes and with cave

systems beneath the land surface

Karst topography is marked by underground cav es and numerous surface sinkholes A major river maycross the region but small surface streams generally disappear down sinkholes

Karst Sinkholes and Subsidence

Burnham

UP

MGB 200x

Subsidence Due to Karst

Natural developmentof sinkholes andunderground streamsin limestone areas is

a major factor in thesubsidence of certainareas of Baguio Cityincluding

Crystal CaveDominicanIrisanLourdes

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2024

eol 11 1st Sem AY2011-12 91920

DNJ

Ground subsidence in Crystal cave

(MGB 2006)

Satellite View mdash

Karst

Topography

Source Photograph copy NASA

Karstic

Area

Tower Karst

Southeastern China

Luoping Yunnan province China

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2124

eol 11 1st Sem AY2011-12 91920

DNJ

Arecibo Radio-telescope Puerto Rico

Restificar et al (2006)Protection of Karst in thePhilippinesActa

Carsologica 35 1 121 ndash

130

Restificar et al (2006) Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Restificaret al (2006)Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Chocolate Hills Bohol

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1724

eol 11 1st Sem AY2011-12 91920

DNJ

Geologic work of groundwater

bull Features found within caverns

ndash Composed of dripstone (travertine)

ndash Calcite deposited as dripping water evaporates

ndash Collectively they are called speleothems

ndash Includes stalactites (hanging from the ceiling)

and stalagmites (form on the floor of a cavern)

Chemical Weathering of Carbonates

bull Carbonic acid dissolves the calcite in limestoneliberating CO2 and dissolved Ca2+

bull Carbonates exposed to

rain continuously dissolve

bull This dissolution results

in caverns and karst

topography

bull stalactites icicle-like pendants of dripstone hanging from

cave ceilings generally slender and are commonly aligned

along cracks in the ceiling which act as conduits for

ground water

bull stalagmites cone-shaped masses of drip-stone formed on

cave floors generally directly below stalactites

Water moves along fractures and bedding planes inlimestone dissolving the limestone to form cavesbelow the water table

Falling water table allows cave system now greatlyenlarged to fill with air Calcite precipitation formsstalactites stalagmites and columns above thewater table

Catastrophic Subsidence Caves

Collapse intocaverns

Caverns producedby dissolution of limestone by acidicwaters

Acid produced when CO2 dissolves in water (carbonic acid)

Rock dissolves below water table

Dropping water table leaves behind caverns

Formation of Sinkholes

Weakened caveroofs collapse

Often due topumping of groundwater(water helpssupportoverlying rock)

Over 4000 sinkholes have formed since1900 in Alabama alone

Sinkholes

Winter Park Florida sinkhole (100m across x 34 m deep) formed1981

ldquoDecember giantrdquo sinkhole Alabama (130 m long x 46m

deep) formed 1972

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1824

eol 11 1st Sem AY2011-12 91920

DNJ

Original artwork by Gary Hincks

bull Composed of dripstone (travertine) calcite deposited as

dripping water evaporates

bull Collectively they are called speleothems

bull Stalactites (ceiling) and stalagmites (floor)

Cavern FeaturesldquoSoda strawsrdquo in Carlsbad Caverns National Park

Kartchner Caverns Arizona

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1924

eol 11 1st Sem AY2011-12 91920

DNJ

Speleothems in Carlsbad Caverns National Park Geologic work of groundwater

bull Karst topography

ndash Landscapes that to a large extent have been shapedby the dissolving power of groundwater

ndash Some common features include

bull Irregular terrain

bull Sinkhole or sinks (formed by groundwater slowlydissolving the bedrock often accompanied bycollapse)

bull Striking lack of surface drainage (streams)

bull Caves and caverns

bull Tower karst

Karst topography

bull an area with many sinkholes and with cave

systems beneath the land surface

Karst topography is marked by underground cav es and numerous surface sinkholes A major river maycross the region but small surface streams generally disappear down sinkholes

Karst Sinkholes and Subsidence

Burnham

UP

MGB 200x

Subsidence Due to Karst

Natural developmentof sinkholes andunderground streamsin limestone areas is

a major factor in thesubsidence of certainareas of Baguio Cityincluding

Crystal CaveDominicanIrisanLourdes

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2024

eol 11 1st Sem AY2011-12 91920

DNJ

Ground subsidence in Crystal cave

(MGB 2006)

Satellite View mdash

Karst

Topography

Source Photograph copy NASA

Karstic

Area

Tower Karst

Southeastern China

Luoping Yunnan province China

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2124

eol 11 1st Sem AY2011-12 91920

DNJ

Arecibo Radio-telescope Puerto Rico

Restificar et al (2006)Protection of Karst in thePhilippinesActa

Carsologica 35 1 121 ndash

130

Restificar et al (2006) Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Restificaret al (2006)Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Chocolate Hills Bohol

832019 Groundwater Sept2011

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eol 11 1st Sem AY2011-12 91920

DNJ

Original artwork by Gary Hincks

bull Composed of dripstone (travertine) calcite deposited as

dripping water evaporates

bull Collectively they are called speleothems

bull Stalactites (ceiling) and stalagmites (floor)

Cavern FeaturesldquoSoda strawsrdquo in Carlsbad Caverns National Park

Kartchner Caverns Arizona

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1924

eol 11 1st Sem AY2011-12 91920

DNJ

Speleothems in Carlsbad Caverns National Park Geologic work of groundwater

bull Karst topography

ndash Landscapes that to a large extent have been shapedby the dissolving power of groundwater

ndash Some common features include

bull Irregular terrain

bull Sinkhole or sinks (formed by groundwater slowlydissolving the bedrock often accompanied bycollapse)

bull Striking lack of surface drainage (streams)

bull Caves and caverns

bull Tower karst

Karst topography

bull an area with many sinkholes and with cave

systems beneath the land surface

Karst topography is marked by underground cav es and numerous surface sinkholes A major river maycross the region but small surface streams generally disappear down sinkholes

Karst Sinkholes and Subsidence

Burnham

UP

MGB 200x

Subsidence Due to Karst

Natural developmentof sinkholes andunderground streamsin limestone areas is

a major factor in thesubsidence of certainareas of Baguio Cityincluding

Crystal CaveDominicanIrisanLourdes

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2024

eol 11 1st Sem AY2011-12 91920

DNJ

Ground subsidence in Crystal cave

(MGB 2006)

Satellite View mdash

Karst

Topography

Source Photograph copy NASA

Karstic

Area

Tower Karst

Southeastern China

Luoping Yunnan province China

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2124

eol 11 1st Sem AY2011-12 91920

DNJ

Arecibo Radio-telescope Puerto Rico

Restificar et al (2006)Protection of Karst in thePhilippinesActa

Carsologica 35 1 121 ndash

130

Restificar et al (2006) Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Restificaret al (2006)Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Chocolate Hills Bohol

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 1924

eol 11 1st Sem AY2011-12 91920

DNJ

Speleothems in Carlsbad Caverns National Park Geologic work of groundwater

bull Karst topography

ndash Landscapes that to a large extent have been shapedby the dissolving power of groundwater

ndash Some common features include

bull Irregular terrain

bull Sinkhole or sinks (formed by groundwater slowlydissolving the bedrock often accompanied bycollapse)

bull Striking lack of surface drainage (streams)

bull Caves and caverns

bull Tower karst

Karst topography

bull an area with many sinkholes and with cave

systems beneath the land surface

Karst topography is marked by underground cav es and numerous surface sinkholes A major river maycross the region but small surface streams generally disappear down sinkholes

Karst Sinkholes and Subsidence

Burnham

UP

MGB 200x

Subsidence Due to Karst

Natural developmentof sinkholes andunderground streamsin limestone areas is

a major factor in thesubsidence of certainareas of Baguio Cityincluding

Crystal CaveDominicanIrisanLourdes

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2024

eol 11 1st Sem AY2011-12 91920

DNJ

Ground subsidence in Crystal cave

(MGB 2006)

Satellite View mdash

Karst

Topography

Source Photograph copy NASA

Karstic

Area

Tower Karst

Southeastern China

Luoping Yunnan province China

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2124

eol 11 1st Sem AY2011-12 91920

DNJ

Arecibo Radio-telescope Puerto Rico

Restificar et al (2006)Protection of Karst in thePhilippinesActa

Carsologica 35 1 121 ndash

130

Restificar et al (2006) Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Restificaret al (2006)Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Chocolate Hills Bohol

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2024

eol 11 1st Sem AY2011-12 91920

DNJ

Ground subsidence in Crystal cave

(MGB 2006)

Satellite View mdash

Karst

Topography

Source Photograph copy NASA

Karstic

Area

Tower Karst

Southeastern China

Luoping Yunnan province China

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2124

eol 11 1st Sem AY2011-12 91920

DNJ

Arecibo Radio-telescope Puerto Rico

Restificar et al (2006)Protection of Karst in thePhilippinesActa

Carsologica 35 1 121 ndash

130

Restificar et al (2006) Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Restificaret al (2006)Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Chocolate Hills Bohol

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2124

eol 11 1st Sem AY2011-12 91920

DNJ

Arecibo Radio-telescope Puerto Rico

Restificar et al (2006)Protection of Karst in thePhilippinesActa

Carsologica 35 1 121 ndash

130

Restificar et al (2006) Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Restificaret al (2006)Protection of Karst in the PhilippinesActa Carsologica 35 1 121 ndash130

Chocolate Hills Bohol

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2224

eol 11 1st Sem AY2011-12 91920

DNJ

Coron Palawan

Saint Paul Limestone Cave Palawan

Limestone Cliffs - PalawanCallao Limestone caves Cagayan

Hundred Islands - Alaminos

832019 Groundwater Sept2011

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DNJ

The geology of Hundred Islands Wawa Gorge ndash

Montalban Rizal

Hot Water Underground

bull hot springs springs in which the water is

warmer than human body temperature

bull water can gain heat in two ways while

underground

bull ground water may circulate near a magma

chamber or a body of cooling igneous rock

bull ground water may circulate unusually deep in the

earth

Geysers Intermittent hot

fountainscolumns of water

Hot Water Undergroundbull geyser a type of hot spring that periodically

erupts hot water and stream the water is

generally near boiling (100oC)

1

2

3

4

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2424

eol 11 1st Sem AY2011-12 91920

Geothermal Energy

bull Electricity can be generated by harnessing

naturally occurring stream and hot water in

areas that are exceptionally hot underground(geothermal areas)

bull nonelectric uses of geothermal energy include

space heating as well as paper

manufacturing ore processing and food

preparation

Wallyrsquos and Deannarsquos Groundwater

Adventure

httpearthuwaterloocaoutreachmuseumwally-and-deannas-

groundwater-adventure

Isang Maikling KwentoSa buhay ng tubig

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2324

eol 11 1st Sem AY2011-12 91920

DNJ

The geology of Hundred Islands Wawa Gorge ndash

Montalban Rizal

Hot Water Underground

bull hot springs springs in which the water is

warmer than human body temperature

bull water can gain heat in two ways while

underground

bull ground water may circulate near a magma

chamber or a body of cooling igneous rock

bull ground water may circulate unusually deep in the

earth

Geysers Intermittent hot

fountainscolumns of water

Hot Water Undergroundbull geyser a type of hot spring that periodically

erupts hot water and stream the water is

generally near boiling (100oC)

1

2

3

4

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2424

eol 11 1st Sem AY2011-12 91920

Geothermal Energy

bull Electricity can be generated by harnessing

naturally occurring stream and hot water in

areas that are exceptionally hot underground(geothermal areas)

bull nonelectric uses of geothermal energy include

space heating as well as paper

manufacturing ore processing and food

preparation

Wallyrsquos and Deannarsquos Groundwater

Adventure

httpearthuwaterloocaoutreachmuseumwally-and-deannas-

groundwater-adventure

Isang Maikling KwentoSa buhay ng tubig

832019 Groundwater Sept2011

httpslidepdfcomreaderfullgroundwater-sept2011 2424

eol 11 1st Sem AY2011-12 91920

Geothermal Energy

bull Electricity can be generated by harnessing

naturally occurring stream and hot water in

areas that are exceptionally hot underground(geothermal areas)

bull nonelectric uses of geothermal energy include

space heating as well as paper

manufacturing ore processing and food

preparation

Wallyrsquos and Deannarsquos Groundwater

Adventure

httpearthuwaterloocaoutreachmuseumwally-and-deannas-

groundwater-adventure

Isang Maikling KwentoSa buhay ng tubig