20090209 water biology - university of...

Water resource sustainability, groundwater hydrology, and contaminationJames W. JawitzSoil and Water Science Department

Take home messages

• importance of water resources

• how much water is there, and where is it?

• how does water move?

• vulnerability of water quality

Part I: Water Resources

Part II – Groundwater HydrologyPart III – Water Contamination

“Ugly bags of mostly water!”Alien life form 

(to Capt. Jean‐Luc Picard and crew of Enterprise)Star Trek The Next Generation, Season 1 (episode ‘Home Soil’), 1987

“Thousands have lived without love, not one without water.”W. H. AudenPoem “First Things First" written in 1957

Water for a person …• A person can live more than a month without food, but only

about a week, depending on conditions, without water.

• Water constitutes approximately 70% of human body weight.

• A person must consume 2.5 liters of water per day from all sources (drinking, eating) to maintain health. Water regulates the temperature of the human body, carries nutrients and oxygen to cells, cushions joints, protects organs and tissues, and removes wastes.

http://www.epa.gov/safewater/sdwa/30th/index.html

Water for the planet …• Water covers approximately 70% of Earth’s surface

• Water movement constitutes the largest flow of any material through the biosphere

• The ecological importance of fresh water is evident throughout the biosphere

• Fresh water is also critical to human society– Underpins global food production: irrigation, livestock, fisheries, and

aquaculture– Water use for domestic, industrial, hydropower, and recreation crucial

for growing population aspiring to long-term improvements in well-being

Vorosmarty et al., 2004. EOS, 85(48), pp. 509, 513-514

Water for people…• Providing basic sanitation and clean drinking water services

remains a major public health challenge. – more than 1 billion people are without access to clean drinking water, 2.5

billion are without sanitation

• 5,000 people, mostly children, die each day from water-related diarrheal diseases

• One in two hospital beds worldwide is occupied by a person with a water-borne disease. And one in seven graves.

• Violation of the human right to clean water and sanitation is destroying human potential on an epic scale. Overcoming the crisis in water and sanitation is one of the great human development challenges of the early 21st century.

2006 UN Human Development Report

Public Health Revolution (first of three, so far?)

Water for… revealing the mystery of language and awakening the soul

“We walked down the path to the well‐house, attracted by the fragrance of the honeysuckle with which it was covered. Some one was drawing water and my teacher placed my hand under the spout. 

As the cool stream gushed over one hand she spelled into the other the word water, first slowly, then rapidly. I stood still, my whole attention fixed upon the motions of her fingers. 

Suddenly I felt a misty consciousness as of something forgotten — a thrill of returning thought; and somehow the mystery of language was revealed to me. 

I knew then that "w‐a‐t‐e‐r" meant the wonderful cool something that was flowing over my hand. That living word awakened my soul, gave it light, hope, joy, set it free!”

Helen KellerThe Story of My Life, 1903

The water issue today… and yesterday

June 2007 March 2007August 2003

October 1965 September 1980

Earth systems are often studied as Hydrosphere, Atmosphere, Geosphere, Biosphere

• Hydrosphere physical processes: Physical attributes and processes of the traditional global hydrologic or “water cycle”, including runoff, geomorphology, sediment processes, evapotranspiration, moisture transport, and precipitation. The global water cycle encompasses not only hydrologic processes over and under the land surfaces of the earth, but also in its oceans and atmosphere.

•Hydrosphere biological and biogeochemical components: Includes aquatic and riparian organisms and their associated ecosystems and biodiversity. These organisms are also integral to the geochemical functioning of the global water system and not simply recipients of changes in the physico-chemical system. Hence we also include here the biogeochemistry of the global water system and water quality.

Hydrologic Cycle

UGSS Circular 1139http://pubs.usgs.gov/circ/circ1139/pdf/circ1139.pdf

What about humans?

• We left humans out of the Earth systems above (except in the biosphere):

• Human intervention in the hydrologic cycle defines water resources• Corollary to the hydrologic cycle: Hydraulic cycle

• The sum of water-related organizations, engineering works, and water use sectors. Society is not only a component of the global water system but also a significant agent of change within the system. Society is not only exposed to changes in water availability but also takes actions to mitigate or adapt to these changes.

Hydraulic cycle

• Source• Treatment• Distribution• Use• Collection• Treatment• Disposal

Chadwick and Moffett, 1998. Hydraulics in Civil and Environmental Engineering

Water SourceSurface WaterGroundwater

Water Treatment

Withdrawal

Distribution

Water UsePublic, Commercial,

Industrial, Institutional

Wastewater Treatment

WastewaterCollection

Disposal

Fresh Water Withdrawal

• Importance of agricultural use• Regional effects

Fraction of annual

renewable water resources

withdrawn (%)

Domestic Use (%)

Industrial Use (%)

Agricultural Use (%)

World 8 8 23 69 Egypt 97 7 5 88 Libya 404 15 10 75 United States 19 12 46 42

Gleick, 1993 or online version at http://worldwater.org

Earth’s Water Resources

Everything else (2.80%)

Oceans (97.20%)

Hydrosphere

All water in the atmosphere, soil, rivers, lakes, and wetlands: 0.03% of total on Earth.

Groundwater (0.62)

Everything else (0.03)

Glaciers (2.15)

Non-Ocean Components

Most freshwater is in the ice caps and below the ground

• All water in the atmosphere, soil, rivers, lakes, and wetlands: 0.03% of total on Earth.

• 2/3 of freshwater in polar ice caps– Antarctic ice sheet: 80% of the world’s ice– Covers an area almost 1.5 times the U.S. – Sea level would rise about 300 feet if the ice melted

• Groundwater represents 95% of availablefreshwater

The Antarctic ice sheet average thickness is nearly 1 mile (~ 2 km)

December 1997

http://airsports.fai.org/may98/may9804.html

Glacier Retreat

Rhone Glacier,Switzerland

2001

1930

Gary Braasch

Glacier Retreat

Rhone Glacier,Switzerland

2001Gary Braasch

1859

“shifting baseline syndrome”?Pauly, 1995 (fisheries)

Part II: Groundwater Hydrology

Who uses groundwater?

Ref 3.1, Alley, W.M., Reilly, T.E., and O.L. Franke, 1999, Sustainability of Ground-Water Resources. United States Geological Survey Circular 1186, USGS: Denver, CO. http://water.usgs.gov/pubs/circ/circ1186

Why do people use groundwater?

• Local springs• Not enough rainfall• Abundant supply• Water quality

Suwannee River State Park, FLPhoto by me.

Aquifer: n. body of permeable rock able to hold or transmit water [Latin: aqua + fer]

• Confined aquifer – Wedged between layers of relatively impermeable

materials and consequently under pressure.

• Unconfined aquifer – Water table is the upper boundary. Because the aquifer

is not under pressure the water level in a well is the same as the water table outside the well. An unconfined aquifer is near the earth's surface causing it to be easily recharged locally as well as contaminated.

Unconfined vs Confined

• Contamination issues?

Porosity = …

• Ratio of void spaces in a geologic formation to the total volume of the formation.

• Intergranular vs intragranular (also interparticle/intraparticle)

• Primary vs secondary

T

v

VV

=η

Intergranular Porosity

Water table = top of the zone of saturation (where pores are saturated with water)

• Relationship between water table and groundwater flow?– Hydraulic gradient (ΔH/Δx): slope of top of water table

• Water pressure is equal to atmospheric pressure• Water table depth fluctuates with climate

conditions on the land surface above and is usuallygently curved and follows a subdued version of the land surface topography.

Dynamics of water table connected to near-surface processes

• Infiltration from surface vs evapotranspiration• Influent vs effluent streams• “saturated zone” is a dynamic definition

Vadosezone

Vadose zone = between ground surface and water table

• Water pressure is less than atmospheric• ‘vadosus’

Groundwater flow – Darcy’s Law

• Darcy’s Law

• Porewatervelocity (for saturated porous media)

qQA

Kddl

= = −φ

vq

=η

unsaturated a bit more complex

cross-sectional area

hydraulic conductivity

pressure (potential energy)

distance

water flow rate

Monument to Henry DarcyDijon, France

Three Pilgrims in Hydrology Heaven

Hydraulic Gradient

• Natural groundwater flow• Groundwater is not sitting still!

– But is moving slowly…– Travel time for 10 m vs 1 km?

Definition of residence time

• The period of time that water remains in a system

τ = V/Q• How long does groundwater spend in an

aquifer?• Turnover time is inverse of residence time

Residence Time and Vulnerability

Tarbuck and Lutgens, Physical Geology

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Floridan Aquifer System: Thickness in Feet

Florida has 331 first-magnitude springs (out of 78 nationwide)

• First-magnitude springs– Flow > 100 cfs (> 65

MGD)– Biggest? 2

• Upper Floridan –confining unit?

1 2002 revision (classifications have changed since 1970s; karst window vs spring-seep, etc)2 SS 820 cfs (530 MGD)

Hydrogeology of South FloridaWest Palm

BeachLake

OkeechobeeFt. Myers Labelle

2300

2100

1900

1700

1500

1300

1100

900

700

500

300

1000

Water Table Aquifer

Lower Confining Unit

Boulder Zone

Lower Floridan Aquifer

Middle Confining Unit

Upper Floridan Aquifer

Mid Hawthorn Aquifer

Lower Tamiami Aquifer

Biscayne

Sandstone Aquifer

Aquifer

WEST EASTDisposal Disposal WellWell

ASR ASR WellWell

Hawthorn Confining Zone

Discharged to the ground: landapplication systems (drain fields, percolation ponds, sprayfields) and reuse systems

Marella, R.L., 2004, Water withdrawals, use, discharge, and trends in Florida,2000: U.S. Geological Survey Scientific Investigations Report 2004-5151, 136 p.

Part III: Water Contamination

Risk Assessment: Three components

• Contaminant Source– site characterization

• Transport – site characterization/transport processes -> model

• Receptor– Exposure pathways -> water and soil standards

Sources of contamination• Point source

– Gas station– Dry cleaner– Landfill– Deep-well injection– Other spills and disposal sites

• Nonpoint source– Agriculture– Wastewater

• Leaky sewers• Septic tanks

– Other wide-area sprays… (mosquito control; Goshutes)

Point source

Agricultural surface water drainage in the Everglades Agricultural Area (EAA) –nutrients (C, N, P), pesticides (photo from SFWMD)

Non-point source

In July 1945, DDT was widely hailed as a progressive measure to eradicate disease-bearing mosquitoes without posing a risk to human health. In this photo from a beach on Long Island, New York, a new insecticide-spraying machine is tested as beachgoers play in the mist. Although this chemical contact is obvious, many other sources of environmental chemical exposure are more difficult to identify.

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DDTPowerful InsecticideHarmless to Humans

Applied byTODD Insect Fog Applicator

Groundwater Contaminants

• Solutes– Organic– Inorganic

• salt

• Others?– Sediment– Biological (bacteria, viruses)

Contaminant Source Zone• Nonaqueous phase liquid (NAPL) contamination of groundwater

– immiscible with water – but enough dissolves to contaminate

DNAPL

GW Flow

Residual & Separate Phase Material

Solute Transport in One Slide

• Advection – physical mechanism by which pollutants are transported along with the flow of subsurface water

• Dispersion – spreading caused by ‘differential advection’

• Reactions– Sorption/desorption– Degradation

Dispersion conceptualized as differential advection

Chess-based alternatives for dealing with groundwater contamination

• When in check, four alternatives:– Check mate

– Move the king out of check

– Block the attack

– Remove the attacker

Alternate water supply

Source management (Containment)Plume management (PAT)

Source removal

Illinois and Michigan Canal

• 1836 – 1848 Constructed for cargo transport, 100 miles

• 1848 sugar from New Orleans passed through I&M Canal

• 1849 first of annual cholera outbreaks

What is cholera?

• Acute, diarrheal illness caused by infection of the intestine with the bacterium Vibrio cholerae.

• The infection is often mild or without symptoms, but sometimes it can be severe.

• Approximately one in 20 infected persons has severe disease characterized by profuse watery diarrhea, vomiting, and leg cramps.

• In these persons, rapid loss of body fluids leads to dehydration and shock.

• Without treatment, death can occur within hours.

http://www.cdc.gov/ncidod/dbmd/diseaseinfo/cholera_g.htmhttp://www.cdc.gov/ncidod/dbmd/diseaseinfo/cholera_g.htm

The Hall of Forgotten Presidents

• James K. Polk, President 1845 - 1849• “President Polk worked extremely hard during his

term and at the end of it, suffering from exhaustion, decided to return to private life even though he remained popular and probably could have won a second term. He also felt he had achieved what he had set out to do, and simply didn't need to return to the office. At the age of only 53, he died at his Nashville home a mere three months after leaving office.”

http://www.paulsilhan.com/hallpres.htmhttp://www.paulsilhan.com/hallpres.htm

Cholera today

WHO alerts (January 2006)

December 2008, Zimbabwe> 3000 deaths

Hamburg, Germany 1892

Dhaka, Bangladesh 2005Beds with plastic sheets, note the hole for drainage.

www.nationalgeographic.com

1854 Soho, London

860 cholera deaths

Dr. John Snow

Data map(see Edward Tufte)

www.nationalgeographic.com

http://www.ph.ucla.edu/epi/snow/snowpub.html

Broad Street Pump

“DEATH’S DISPENSARY: Open to the poor, gratis”

Cartoon from 1866 (by George John Pinwell) by which time most physicians and public health officials had finally been convinced that cholera was spread through the water supply.

American Scientist, May‐June 2007

By the 1880s, Chicago's sewage flowed from the Chicago River past the Two Mile Crib, the source of Chicago's drinking water in Lake Michigan. Epidemics of typhoid and other diseases led to the establishment, in 1889, of the Sanitary District of Chicago (nowMetropolitan Water Reclamation District).

http://en.wikipedia.org/wiki/Chicago_Sanitary_and_Ship_Canal

Engineered landscape: Human modifications to the natural Chicago River

While the Sanitary and Ship Canal resulted in 91% drop in the rate of typhoid deaths in Chicago by 1908, Chicago's water supply was not truly safe until the addition of chlorine to the water in 1912. By 1917 Chicago's typhoid death rate had fallen to lowest of any major city in the nation.

Chicago Public Libraryhttp://www.chipublib.org/digital/sewers/history4.html

1995 Motor vehicle accident deaths17 per 100,000

West Bengal/Bangladesh

• About 10% of global population lives in the Ganges-Brahmaputra delta

• Sediments carried by the rivers transformed the landscape to one of the most fertile lands of the world

Arsenic in Groundwater• What is the source?• What are the pathways?• What is the remedy?

http://international.usgs.gov/projects/bg_arsenic.htm

Woburn, MA• Leukemia cluster• Contamination of drinking water

not recognized for decades

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Groundwater Protection Zone

(Wellhead protection)

In situ flushing source zone remediation: Injection and extraction of chemical additives to solubilize(or mobilize) NAPLs from the subsurface

GW Flow

Injection WellRecoveryWell

2 PV 4 PV1 PV 9 PV6 PV

Jawitz et al., 1998. ES&T, 32(4).

Mass Reduction: SPME at Hill AFB

Remediation Performance Evaluation: Mass Removal

Hill AFB cosolvents (1994-1995) ~82%Hill AFB microemulsions (1996) ~90%CFB Borden cosolvents (1997) ~70%Dry cleaner site, Jacksonville, FL (1998) ~64%Dover AFB cosolvents (1998-1999) ~62%Dover AFB surfactants (2000) ~68%

Fraction of mass removed