Hydrologic Cycle/Water Supply
Aquifers/Properties Well Construction
Hydrologic Cycle/Water Supply
Aquifers/Properties Well Construction
Waterworks OperationsWQT 111
Lecture 1
Waterworks OperationsWQT 111
Lecture 1
http://ga.water.usgs.gov/edu/watercycle.html Albany and Purdue
http://www.purdue.edu/dp/envirosoft/private/src/main.htm
ObjectivesObjectives
Parts the Hydrologic CycleParts the Hydrologic Cycle
Aquifer TypesAquifer Types
Porosity vs. PermeabilityPorosity vs. Permeability
Water Sources and SupplyWater Sources and Supply
Groundwater ProblemsGroundwater Problems
Well Construction and MaintenanceWell Construction and Maintenance
The objectives of today’s lecture are to learn the basics of:The objectives of today’s lecture are to learn the basics of:
Sources of Drinking WaterSources of Drinking Water
• Surface water
• Ground water
• Desalinated sea water
• Rain water
• Surface water
• Ground water
• Desalinated sea water
• Rain water
Many sources of water are directly suitable for drinking purposes without treatment?
Many sources of water are directly suitable for drinking purposes without treatment?
Tru
e
Fal
se
67%
33%
1. True
2. False
1. True
2. False
Source waters include these two broad categories
Source waters include these two broad categories
Surfa
ce w
ater
...
Res
ervo
irs a
nd...
Res
ervo
irs a
nd...
Flo
win
g wat
er ..
.
86%
7%7%0%
1. Surface water and ground water
2. Reservoirs and wells
3. Reservoirs and ground water
4. Flowing water and stagnant water
1. Surface water and ground water
2. Reservoirs and wells
3. Reservoirs and ground water
4. Flowing water and stagnant water
The Drinking Water Cycle
Water System
Distribution System
Sewer Lines
Wastewater Plant
Discharge
Homes or Businesses
Septic System
Infiltration
Source(aquifer, lake,
etc.)
Distribution of Earths WaterDistribution of Earths Water
Water For Human ConsumptionWater For Human Consumption
• 98% of available fresh water for human use is groundwater
• 98% of available fresh water for human use is groundwater
• We use 100 gal/day per person• We use 100 gal/day per person
Water For Human ConsumptionWater For Human Consumption
• 50% of US population (municipal water systems)
• 45-50% of US population groundwater
• 50% of US population (municipal water systems)
• 45-50% of US population groundwater
The mineral content and water quality of a particular well is usually pretty consistent.
The mineral content and water quality of a particular well is usually pretty consistent.
Tru
e
Fal
se
7%
93%1. True
2. False
1. True
2. False
What percentage of the water used in the United States comes
from underground sources?
What percentage of the water used in the United States comes
from underground sources?
45%
30%
60%
90%
56%
25%19%
0%
1. 45%
2. 30%
3. 60%
4. 90%
1. 45%
2. 30%
3. 60%
4. 90%
Nearly 95 percent of the rural population of the US relies on
ground water.
Nearly 95 percent of the rural population of the US relies on
ground water.
Tru
e
Fal
se
0%
100%1. True
2. False
1. True
2. False
It is estimated that daily water usage in the U.S is 88 billion gallons per day, two thirds of
which is used for crop irrigation.
It is estimated that daily water usage in the U.S is 88 billion gallons per day, two thirds of
which is used for crop irrigation.
Tru
e
Fal
se
20%
80%1. True
2. False
1. True
2. False
Hydrologic CycleHydrologic Cycle• Water moves from earth to sky
(evaporation and transpiration)
• Water vapor forms tiny droplets (condensation=clouds)
• Water falls back to earth (precipitation)
• Water on the earth penetrates the ground or runs off the surface (infiltration, percolation, surface runoff)
• Water moves from earth to sky (evaporation and transpiration)
• Water vapor forms tiny droplets (condensation=clouds)
• Water falls back to earth (precipitation)
• Water on the earth penetrates the ground or runs off the surface (infiltration, percolation, surface runoff)
EvapotranspirationEvapotranspiration
RechargeRecharge
Ground WaterGround WaterGround Water / Surface Water
InteractionGround Water / Surface Water
Interaction
StreamStream
LakeLake
PrecipitationPrecipitation
Plant UptakePlant UptakeLakeLake
Surface RunoffSurface Runoff
Riparian Zone
Riparian Zone
WetlandWetland
Hydrologic Cycle
http://ga.water.usgs.gov/edu/watercycle.html
(solid to gas)
Ocean
Evaporation Evapo-transpiration
runoff
Water Supply
Discharge treated water
Salt Water IntrusionAquifer
Infiltration
Recharge
Evaporation
Extraction
Precipitation
PrecipitationEvaporation/ETSurface WaterGroundwater
Soil moistureInfiltration (Art)
ExtractionReturn flowTreated water Aquifer intrusion
Soil moisture
Soil moisture
Detailed Hydrologic Cycle
Kennedy 2003
Condensation
http://ga.water.usgs.gov/edu/watercycle.html
Evaporation
http://ga.water.usgs.gov/edu/watercycle.html
Transpiration
http://ga.water.usgs.gov/edu/watercycle.html
Infiltration
http://ga.water.usgs.gov/edu/watercycle.html
Water TableWater Table• zone of aeration (vadose)
= air and water in pores (unsaturated)
• zone of saturation = water only in pores
• groundwater = water beneath soil and above bedrock
• zone of aeration (vadose) = air and water in pores (unsaturated)
• zone of saturation = water only in pores
• groundwater = water beneath soil and above bedrock
Ground WaterGround Water
UNSATURATEDZONE
Ground Water
UNSATURATEDZONE
WATER TABLE
ZONE OFSATURATION
Aquifer Types
Aquifers and Wells
Artesian wells are defined asArtesian wells are defined as
Hav
ing w
ater
u...
Bei
ng loca
ted ..
.
Any
wel
l use
d ...
Wel
ls c
ompl
ete.
..
This
des
ignat
i...
20% 20% 20%20%20%1. Having water under a
pressure greater than atmospheric which causes the water to rise
2. Being located in an aquifer more than 200 feet deep
3. Any well used to pump high quality drinking water
4. Wells completed less then 25 ft below the ground
5. This designation is just a clever marketing ploy as it applies to all wells
1. Having water under a pressure greater than atmospheric which causes the water to rise
2. Being located in an aquifer more than 200 feet deep
3. Any well used to pump high quality drinking water
4. Wells completed less then 25 ft below the ground
5. This designation is just a clever marketing ploy as it applies to all wells
Confined AquiferConfined Aquifer
Porosity and PermeabilityPorosity and Permeability
• porosity = percent pore space in sediment or rock
• permeability = capability of a substance to allow the passage of water
– depends on porosity and connectivity of pores or fractures
• porosity = percent pore space in sediment or rock
• permeability = capability of a substance to allow the passage of water
– depends on porosity and connectivity of pores or fractures
Porosity and PermeabilityPorosity and Permeability
• high porosity materials:
– clay, sand, well sorted gravel
• low porosity materials
– granite, gabbro, metamorphic rocks
– may have high permeability due to fractures
• high porosity materials:
– clay, sand, well sorted gravel
• low porosity materials
– granite, gabbro, metamorphic rocks
– may have high permeability due to fractures
Porosity and PermeabilityPorosity and Permeability
Clay Porosity and PermeabilityClay Porosity and Permeability
• Clay is a high porosity material!!!
• Clay is a low permeability material!!!
• Clay is a high porosity material!!!
• Clay is a low permeability material!!!
Porosity may be defined as Porosity may be defined as
The
perce
ntage.
..
The
ratio
of f
...
The
number
of .
..
None
of the
se ..
.
25% 25%25%25%1. The percentage of open
space or voids in a particular soil
2. The ratio of filtered to reject water for a sand filter
3. The number of wells sunk per area into a particular aquifer
4. None of these is correct
1. The percentage of open space or voids in a particular soil
2. The ratio of filtered to reject water for a sand filter
3. The number of wells sunk per area into a particular aquifer
4. None of these is correct
Limestone has more porosity than clay?
Limestone has more porosity than clay?
Tru
e
Fal
se
81%
19%
1. True
2. False
1. True
2. False
As groundwater moves through the soil, this type of material may be removed as the soil behaves
like a natural filter.
As groundwater moves through the soil, this type of material may be removed as the soil behaves
like a natural filter.
Susp
ended
mat
e...
Dis
solv
ed m
ate.
..
Sal
ts
Am
mon
ia a
nd o
t...
91%
0%0%9%
1. Suspended material
2. Dissolved material
3. Salts
4. Ammonia and other nitrogen compounds
1. Suspended material
2. Dissolved material
3. Salts
4. Ammonia and other nitrogen compounds
Specific yield may be defined as:Specific yield may be defined as:
The
amount o
f ...
The
amount o
f ...
The
amount o
f ...
The
amount o
f ...
15%8%
62%
15%
1. The amount of water that a particular volume of rock or soil will produce when drained by gravity.
2. The amount of water that a particular well produces when drained by gravity.
3. The amount of water that a particular well produces when pumped forceably.
4. The amount of water that may be squeezed from a volume of rock or soil with a Vadose press.
1. The amount of water that a particular volume of rock or soil will produce when drained by gravity.
2. The amount of water that a particular well produces when drained by gravity.
3. The amount of water that a particular well produces when pumped forceably.
4. The amount of water that may be squeezed from a volume of rock or soil with a Vadose press.
How much water is produced by a given well depends on which of
the following factors?
How much water is produced by a given well depends on which of
the following factors?
The
aquife
r
The
pump
The
wel
l
All
of the
abo...
0%
100%
0%0%
1. The aquifer
2. The pump
3. The well
4. All of the above
1. The aquifer
2. The pump
3. The well
4. All of the above
Well ConstructionWell Construction
• Wells should be at least 5 ft from any building
• Easy to access for repair and maintenance• Typically casing extends 1 to 2 feet above
the surrounding land • Properly fitted pump and pipes (to handle
demand)• Proper gravel pack and well completion• Disinfect w/ 100 mg/L available chlorine
• Wells should be at least 5 ft from any building
• Easy to access for repair and maintenance• Typically casing extends 1 to 2 feet above
the surrounding land • Properly fitted pump and pipes (to handle
demand)• Proper gravel pack and well completion• Disinfect w/ 100 mg/L available chlorine
Well/Pump PartsWell/Pump Parts• Properly fitted pump
– well pump pedestal- supports the weight of the pumping unit.
– Well pump motor base seal -watertight seal between the motor base and the concrete support pedestal.
– well pump blow-off -remove first water (usually sandy) pumped at start-up
– well casing vent (3”)- air enters well during drawdown to prevent vacuum conditions. Vents excess air during well recovery period.
– Air-release vacuum breaker valve (125 psi) -Permits discharge of air in column pipe during start-up and admits air during shutdown.
• Properly fitted pump – well pump pedestal- supports the weight of the pumping
unit.– Well pump motor base seal -watertight seal between the
motor base and the concrete support pedestal.– well pump blow-off -remove first water (usually sandy)
pumped at start-up – well casing vent (3”)- air enters well during drawdown to
prevent vacuum conditions. Vents excess air during well recovery period.
– Air-release vacuum breaker valve (125 psi) -Permits discharge of air in column pipe during start-up and admits air during shutdown.
Well MaintenanceWell Maintenance• Water level in well measured with a
sounder
• Hydrochloric and Sulfamic acid can be used to remove well crust. Chlorine to remove iron bacteria (new well 50 mg/l 24 hrs; old well 100-200 mg/L for shock)
• Well surging- physical cleaning of the well
• Water level in well measured with a sounder
• Hydrochloric and Sulfamic acid can be used to remove well crust. Chlorine to remove iron bacteria (new well 50 mg/l 24 hrs; old well 100-200 mg/L for shock)
• Well surging- physical cleaning of the well
New WellsNew Wells
1. Add enough chlorine to produce a concentration of 50 mg/L in the well casing.
2. Turn the pump on and off several times to mix the well (agitate).
3. Re-mix well several times at one-hour intervals.
4. Wait 24 hours.
5. Pump well water to waste until chlorine smell is gone.
6. Test for chlorine residual @ well sampling tap
7. Collect a bacteriological sample.
1. Add enough chlorine to produce a concentration of 50 mg/L in the well casing.
2. Turn the pump on and off several times to mix the well (agitate).
3. Re-mix well several times at one-hour intervals.
4. Wait 24 hours.
5. Pump well water to waste until chlorine smell is gone.
6. Test for chlorine residual @ well sampling tap
7. Collect a bacteriological sample.
What concentration of residual chlorine should be maintained
for 24 hours in a newly constructed well?
What concentration of residual chlorine should be maintained
for 24 hours in a newly constructed well?
50
mg/L
50
ug/L
25
mg/L
25
ug/L
100%
0%0%0%
1. 50 mg/L
2. 50 ug/L
3. 25 mg/L
4. 25 ug/L
1. 50 mg/L
2. 50 ug/L
3. 25 mg/L
4. 25 ug/L
What is the purpose of surging?What is the purpose of surging?
To c
lean
min
er...
To re
move
blo
c...
To b
ackw
ash fi
...
To p
repar
e pum
...
80%
0%7%
13%
1. To clean mineral deposits from well screens.
2. To remove blockages from the distribution system.
3. To backwash filters rapidly.
4. To prepare pump motors for erratic power supplies.
1. To clean mineral deposits from well screens.
2. To remove blockages from the distribution system.
3. To backwash filters rapidly.
4. To prepare pump motors for erratic power supplies.
Chlorine (100-200 mg/L) is an effective treatment for well
screens. It helps to remove this material.
Chlorine (100-200 mg/L) is an effective treatment for well
screens. It helps to remove this material.
Slim
e fro
m ir
o...
Bio
film
s fro
m ..
.
Iron a
nd m
anga.
..
Cal
cium
car
bon...
77%
0%
15%8%
1. Slime from iron-oxidizing bacteria
2. Biofilms from ammonia-oxidizing bacteria
3. Iron and manganese oxides
4. Calcium carbonate deposits
1. Slime from iron-oxidizing bacteria
2. Biofilms from ammonia-oxidizing bacteria
3. Iron and manganese oxides
4. Calcium carbonate deposits
Chlorine treatment of wells is sometimes referred to as ________
treatment because of the high concentrations of chlorine that is
agitated (100 and 200 mg/L).
Chlorine treatment of wells is sometimes referred to as ________
treatment because of the high concentrations of chlorine that is
agitated (100 and 200 mg/L).
Shock
Slu
g
Atte
nuat
ed
Chlo
ro-b
iotic
100%
0%0%0%
1. Shock
2. Slug
3. Attenuated
4. Chloro-biotic
1. Shock
2. Slug
3. Attenuated
4. Chloro-biotic
Finished Well Finished Well
• Drilled by cable tool method or rotary hydraulic• Sanitary seal top of the well • Surrounded by a 4-inch thick sloping slab extending at
least 2 feet in all directions• Typically casing extends 1 feet above 100 year flood line • Grout seal well casing with concrete or clay• Well screen keeps out particulates and allows water into
well (properly fitted slot size)• Proper sized pump
• Drilled by cable tool method or rotary hydraulic• Sanitary seal top of the well • Surrounded by a 4-inch thick sloping slab extending at
least 2 feet in all directions• Typically casing extends 1 feet above 100 year flood line • Grout seal well casing with concrete or clay• Well screen keeps out particulates and allows water into
well (properly fitted slot size)• Proper sized pump
Finished Well Finished Well
Well screen
Grout seal
Problems: Contaminated Aquifers
Sources of Contamination
Problems: Overpumping/Land subsidence
USGS Fact Sheet-165-00December 2000
This condition results when more water is removed from an aquifer than is replaced through
rain and snowmelt.
This condition results when more water is removed from an aquifer than is replaced through
rain and snowmelt.
Ove
rdra
ft
Dry
wel
ling
Ris
ing
water
t...
Air
bindin
g
100%
0%0%0%
1. Overdraft
2. Dry welling
3. Rising water table
4. Air binding
1. Overdraft
2. Dry welling
3. Rising water table
4. Air binding
Problems: Overpumping/Land subsidence
20-40ft decline
Problems: Salt Water Intrusion
Potential problems that can affect wells are
Potential problems that can affect wells are
Ove
rdra
ft
Gro
undw
ater
po...
Sal
t wat
er In
t...
All
of the
abo...
7%
93%
0%0%
1. Overdraft
2. Groundwater pollution
3. Salt water Intrusion
4. All of the above
1. Overdraft
2. Groundwater pollution
3. Salt water Intrusion
4. All of the above
The objectives stated in the syllabus to learn the basics of
(Parts the Hydrologic CycleAquifer types, Porosity/permeability, Well
construction, Groundwater problems) were met ?
The objectives stated in the syllabus to learn the basics of
(Parts the Hydrologic CycleAquifer types, Porosity/permeability, Well
construction, Groundwater problems) were met ?
Stro
ngly A
gree
Agre
e
Dis
agre
e
Stro
ngly D
isag
ree
80%
0%0%
20%
1. Strongly Agree
2. Agree
3. Disagree
4. Strongly Disagree
1. Strongly Agree
2. Agree
3. Disagree
4. Strongly Disagree