Welcome to:Welcome to:

Water Quality and TreatmentWater Quality and Treatment

EH ProgramEH Program

Guang JinGuang Jin

Introduce YourselfIntroduce Yourself

What makes you to choose this What makes you to choose this course?course?

What do you expect to get out What do you expect to get out from this course?from this course?

I. Water QualityI. Water Quality

A. A History of Water QualityA. A History of Water Quality

Source of water and changes in Source of water and changes in water quality throughout historywater quality throughout history

ObjectivesObjectives

Students should be able to:Students should be able to:– Describe the source of water on Describe the source of water on

Earth.Earth.– Describe how water quality has Describe how water quality has

changed throughout history due to changed throughout history due to human actionshuman actions

Source of Water Source of Water on Earthon Earth

About 3 billions years ago, the Earth cooled About 3 billions years ago, the Earth cooled enough for hydrogen and oxygen to enough for hydrogen and oxygen to combine in the atmosphere to form water.combine in the atmosphere to form water.

Torrential rains occurred for millions of Torrential rains occurred for millions of years, washing salts and other minerals into years, washing salts and other minerals into low areas to form lakes, rivers and oceans.low areas to form lakes, rivers and oceans.

Changes in water quality Changes in water quality throughout historythroughout history

Physical, chemical, and biological Physical, chemical, and biological “contaminants” have always been “contaminants” have always been present in water in low present in water in low concentrations.concentrations.

Human activities have changed water Human activities have changed water quality dramatically because of high quality dramatically because of high population and synthetic chemicals.population and synthetic chemicals.

Changes in water quality Changes in water quality throughout history throughout history

Several major changes in the past Several major changes in the past few hundred years have changed few hundred years have changed water quality dramatically:water quality dramatically:– changed in animal populationchanged in animal population– changes in plant populationschanges in plant populations– introduction of “persistent” and introduction of “persistent” and

biomagnified” synthetic chemicals, biomagnified” synthetic chemicals, and other human wastes.and other human wastes.

Destruction of animal Destruction of animal populationspopulations

Beavers once slowed rates of water runoff Beavers once slowed rates of water runoff and allowed percolation of waterand allowed percolation of water

Prairie dogs and other rodents allowed quick Prairie dogs and other rodents allowed quick recharge of groundwater through borrows.recharge of groundwater through borrows.

Buffalo and other grazers created “wallows” Buffalo and other grazers created “wallows” to create groundwater recharge zonesto create groundwater recharge zones

Freshwater mussels filtered water to Freshwater mussels filtered water to improve water qualityimprove water quality

Changes in plant Changes in plant populationpopulation

Vast forests once captured water and Vast forests once captured water and released it slowly into the environmentreleased it slowly into the environment

Vast grassland prairies also slowed Vast grassland prairies also slowed movement of water through the movement of water through the environment.environment.

Agricultural “monocultures”, plowing, Agricultural “monocultures”, plowing, and damming of rivers created changes and damming of rivers created changes in both plant and animal populationsin both plant and animal populations

Human-made WastesHuman-made Wastes

Human designed synthetic organic Human designed synthetic organic chemicals which are “persistent” in the chemicals which are “persistent” in the environment.environment.

Humans capture, use, contaminate, treat, Humans capture, use, contaminate, treat, and release tremendous quantities of water. and release tremendous quantities of water. These wastes contain organic chemicals These wastes contain organic chemicals which can imbalance the natural ability of which can imbalance the natural ability of water to clean itself (BOD, or Biochemicalwater to clean itself (BOD, or Biochemical Oxygen Demand)Oxygen Demand)

SummarySummary

While some water had always While some water had always contained organic and inorganic contained organic and inorganic contaminants, human population has contaminants, human population has increased them significantly in the increased them significantly in the past few hundred years.past few hundred years.

Introduction of “persistent” synthetic Introduction of “persistent” synthetic compounds and other human wastes compounds and other human wastes has created imbalances in natural has created imbalances in natural systems designed to purify water.systems designed to purify water.

B. Aqueducts and ReservoirsB. Aqueducts and Reservoirs

A brief history of drinking water A brief history of drinking water treatment and protectiontreatment and protection

ObjectivesObjectives

Student should be able to:Student should be able to:– Describe the history of water sources, Describe the history of water sources,

treatment, and protection in the U.S. treatment, and protection in the U.S. and Europe.and Europe.

Early water supplies:Early water supplies:

As early as 2500 B.C., the As early as 2500 B.C., the SumeriansSumerians brought clean water from the mountains for brought clean water from the mountains for irrigation and drinking purposes.irrigation and drinking purposes.

Roman Roman aqueductaqueduct systems are a model of systems are a model of engineering efficiency (simple yet effective).engineering efficiency (simple yet effective).

However, early Europeans had poor quality However, early Europeans had poor quality waste treatment and water supplies.waste treatment and water supplies.

Water, waste and diseaseWater, waste and disease Early civilization knew that clean Early civilization knew that clean

water supplies were essential to good water supplies were essential to good health.health.

The relationship of human and animal The relationship of human and animal wastes to waterborne disease was not wastes to waterborne disease was not firmly established until the late firmly established until the late 1800’s. - example of 1800’s. - example of cholera(caused cholera(caused by by Vibrio choleraVibrio cholera))

Typhoid fever (caused by Salmonella typhi) was a problem in the U.S.

Early water sources Early water sources in the U.S.in the U.S.

Most early U.S. cities such as Boston, Most early U.S. cities such as Boston, got their drinking water from well, which got their drinking water from well, which rapidly became polluted with waste.rapidly became polluted with waste.

Like Europe, early U.S. cities were Like Europe, early U.S. cities were subjected to waterborne illness subjected to waterborne illness epidemics.epidemics.

Cities which had relatively clean water Cities which had relatively clean water supplies, such as Philadelphia, were supplies, such as Philadelphia, were noticed to have much lower illness rates.noticed to have much lower illness rates.

Early water Early water treatmenttreatment

Evidence of primary water treatment Evidence of primary water treatment was found in Egypt as early as 2000 was found in Egypt as early as 2000 B.C.B.C.

Pliny described the use of alum and lime Pliny described the use of alum and lime for water treatment in 77 A.D.for water treatment in 77 A.D.

In Englande, use of alum for purifying In Englande, use of alum for purifying drinking water was common.drinking water was common.

In Bolton, Englande in 1881, flocculation In Bolton, Englande in 1881, flocculation was used to treat drinking water.was used to treat drinking water.

Early water treatment Early water treatment in the U.S.in the U.S.

In 1892, Poughkeepsie N. Y. whose water In 1892, Poughkeepsie N. Y. whose water source was the Hudson River, used sand source was the Hudson River, used sand filtration for purifying drinking water.filtration for purifying drinking water.

In 1893, when Lawrence, MA, added water In 1893, when Lawrence, MA, added water filters, and death rate for filters, and death rate for typhoid fevertyphoid fever fell from 134 to 30 per 100,000.fell from 134 to 30 per 100,000.

Allen Hazen of Boston found in 1903 that Allen Hazen of Boston found in 1903 that death rates for other illness also dropped.death rates for other illness also dropped.

Disinfection of water Disinfection of water suppliessupplies

The Union Stockyard company of Chicago The Union Stockyard company of Chicago was sued by City of Chicago for poaching was sued by City of Chicago for poaching municipal water.municipal water.

The stockyard started using water from The stockyard started using water from sewage-polluted Bubbly Creek by adding sewage-polluted Bubbly Creek by adding first copper sulfate, then chloride of lime.first copper sulfate, then chloride of lime.

Cattle first lost weight, then thrived, and Cattle first lost weight, then thrived, and use of chlorine for disinfection was begun.use of chlorine for disinfection was begun.

SummarySummary

The value of clean drinking water supplies The value of clean drinking water supplies has been realized for thousands of years.has been realized for thousands of years.

Physical (filtration, sedimentation) and Physical (filtration, sedimentation) and chemical (flocculation) treatment of chemical (flocculation) treatment of polluted water supplies was shown to polluted water supplies was shown to dramatically reduce the prevalence of dramatically reduce the prevalence of waterborne illness.waterborne illness.

Disinfection (chlorine) was the final step in Disinfection (chlorine) was the final step in reducing waterborne illness.reducing waterborne illness.

C. Importance of water, its C. Importance of water, its unique properties, and its unique properties, and its

distribution on Earthdistribution on Earth

ObjectivesObjectives

Students should be able to:Students should be able to: List and describe unique List and describe unique

characteristics of water than make characteristics of water than make it essential for life.it essential for life.

Discuss the unequal distribution of Discuss the unequal distribution of available freshwater on the Earth available freshwater on the Earth and the U.S.and the U.S.

Importance of WaterImportance of Water

Most organisms are 60-65% water by Most organisms are 60-65% water by weight.weight.

Water is vital for agriculture, Water is vital for agriculture, manufacturing, climate, etc.manufacturing, climate, etc.

Life could not exist without water.Life could not exist without water. 71% of the Earth is covered by water71% of the Earth is covered by water Water is the major feature of the Water is the major feature of the

Earth seen from space.Earth seen from space.

Unique properties of waterUnique properties of water

Liquid over wide temperature Liquid over wide temperature range.range.(BP = 100(BP = 100ooC, FP = 0C, FP = 0ooC)C)

Temperature bufferTemperature buffer Heat exchange (climate)Heat exchange (climate) Polar solventPolar solvent Expand when it freezes. Expand when it freezes.

Distribution of world waterDistribution of world water

Distribution of water on Distribution of water on EarthEarth

97% of water is in the oceans.97% of water is in the oceans. 3% is freshwater3% is freshwater Only 0.003% is easily available as soil Only 0.003% is easily available as soil

moisture, usable groundwater, or in moisture, usable groundwater, or in lakes, rivers, and streamslakes, rivers, and streams

Assume that all water on Earth is Assume that all water on Earth is represented by 100 liter (26 gal.)represented by 100 liter (26 gal.)– less than one gallon would represent al less than one gallon would represent al

freshwaterfreshwater– less than one teaspoonful would be readily less than one teaspoonful would be readily

available freshwateravailable freshwater– Large portions of readily available freshwater Large portions of readily available freshwater

are polluted or inaccessibleare polluted or inaccessible

The distribution of water The distribution of water on Earth is unequalon Earth is unequal

Iceland has an abundance of water Iceland has an abundance of water from precipitationfrom precipitation

The Middle East has severe water The Middle East has severe water shortageshortage

The Northwest U.S. gets large The Northwest U.S. gets large amounts of rainfall due to mountains.amounts of rainfall due to mountains.

The southwest U.S. has severe water The southwest U.S. has severe water deficienciesdeficiencies

SummarySummary

Water is essential to living things Water is essential to living things and is chemically and physically and is chemically and physically unique.unique.

Quality water is extremely limited Quality water is extremely limited and is unequally distributed in the and is unequally distributed in the United States and on the Earth.United States and on the Earth.

D. The Hydrologic CycleD. The Hydrologic Cycle

ObjectivesObjectives

Student should be able to:Student should be able to: Describe and/or diagram the Describe and/or diagram the

hydrologic cycle and distinguish its hydrologic cycle and distinguish its components.components.

Discuss the importance of the Discuss the importance of the hydrologic cycle for purification of hydrologic cycle for purification of water on Earthwater on Earth

The Hydrologic Cycle:The Hydrologic Cycle:

This is a global, natural system in This is a global, natural system in place for purification of water on place for purification of water on Earth, and has several key Earth, and has several key elements:elements:– EvaporationEvaporation (Liquid to gas) (Liquid to gas)– CondensationCondensation (gas to liquid) (gas to liquid)– PrecipitationPrecipitation (rain, snow, sleet, etc.) (rain, snow, sleet, etc.)– Infiltration, percolation, runoffInfiltration, percolation, runoff..

EvaporationEvaporation

Evaporation is conversion of liquid Evaporation is conversion of liquid water into water vapor.water into water vapor.– This process distills the water, leaving This process distills the water, leaving

contaminants behind.contaminants behind. Evaportranspiration is evaporation of Evaportranspiration is evaporation of

water from leaves of plants and soilswater from leaves of plants and soils– functions due to surface tension functions due to surface tension

drawing water from soil to roots and to drawing water from soil to roots and to leaves.leaves.

CondensationCondensation

Absolute humidity is the amount of Absolute humidity is the amount of water that a volume of air can hold.water that a volume of air can hold.

Relative humidity is the amount of Relative humidity is the amount of water in air compared to the maximum water in air compared to the maximum it could hold at a particular it could hold at a particular temperaturetemperature

The dew point is the temperature at The dew point is the temperature at which moisture begins to condense which moisture begins to condense from the air.from the air.

PrecipitationPrecipitation

Moisture condenses on small Moisture condenses on small particles to form condensation nuclei.particles to form condensation nuclei.

Droplets combine until gravity causes Droplets combine until gravity causes them to fall to Earth (rain, snow, them to fall to Earth (rain, snow, sleet).sleet).

15 trillion liters of water (4 trillion 15 trillion liters of water (4 trillion gallons) of water fall on the U.S. gallons) of water fall on the U.S. every day.every day.

Infiltration, percolation, Infiltration, percolation, runoffrunoff

About 66% of precipitation evaporates.About 66% of precipitation evaporates. About 31% runs off land into lakes, rivers, etc. and About 31% runs off land into lakes, rivers, etc. and

eventually, the ocean.eventually, the ocean. About 3% percolates through soils into groundwater.About 3% percolates through soils into groundwater. Some water infiltrates into soils and remains as soil Some water infiltrates into soils and remains as soil

moisturemoisture The hydrologic cycle is powered by energy from the The hydrologic cycle is powered by energy from the

sun and gravity.sun and gravity.– Solar energy evaporates water and forms water vapor.Solar energy evaporates water and forms water vapor.– Winds and air movement transport the water vapor.Winds and air movement transport the water vapor.– Changing temperatures cause condensation and Changing temperatures cause condensation and

precipitation.precipitation.

How humans affect the How humans affect the hydrologic cyclehydrologic cycle

Humans affect the hydrologic cycle Humans affect the hydrologic cycle in two major ways:in two major ways:– By withdrawing huge amounts of By withdrawing huge amounts of

freshwater from well, lakes, streams, freshwater from well, lakes, streams, etc. (this may lead to water etc. (this may lead to water depletiondepletion or or intrusionintrusion of salt water) of salt water)

– By cleaning vegetation for agriculture, By cleaning vegetation for agriculture, mining, roads, etc. (mining, roads, etc. (decreasesdecreases infiltration, percolation, infiltration, percolation, increasesincreases runoff).runoff).

Environmental factors that Environmental factors that affect water quality and affect water quality and

availabilityavailability

ClimateClimate - rain, snow, temperature, etc. - rain, snow, temperature, etc. TopographyTopography - hills, valleys, slopes, etc. - hills, valleys, slopes, etc. GeologyGeology - soil, rock, minerals, etc. - soil, rock, minerals, etc. GeographyGeography - lakes, streams, cities, etc. - lakes, streams, cities, etc. PopulationPopulation - concentration of animals - concentration of animals

and plants.and plants. Water useWater use - drinking, bathing, etc. - drinking, bathing, etc.

SummarySummary

The hydrologic cycle is made up of The hydrologic cycle is made up of several components including several components including evaporation, condensation, and evaporation, condensation, and precipitation.precipitation.

The hydrologic cycle is a natural The hydrologic cycle is a natural process that helps to purify water on process that helps to purify water on Earth.Earth.