Water Use, Overuse, and Natural Contamination

China India Iran Israel Jordan Mexico Morocco Pakistan Saudi Arabia South Korea Spain Syria Tunisia United States Yemen Withdrawals exceed recharge creating deficits in the aquifer Over-exploitation of renewable and non-renewable aquifers Water Mining Lack of contemporary recharge

GROUNDWATER. (Mm 3 /yr) COUNTRYTotal use% Non-renewable Saudi Arabia21,00084% Bahrain25835% Egypt4,85018% Jordan48635% Libya4,28070% Yemen2,20032% Saudi Arabia and Libya, use 77% of the estimated total world extraction of non-renewable groundwater for urban supply and irrigated agriculture. The Middle East

Falls in the water table between 1982 and 2000 range from 3 to 6 feet per year Within 15 years Quetta will run out of water if the current consumption rate continues Pakistan

Water table falling by 8.5 feet per year Iran: Water Refugees over pumping by an average of 5 billion tons (3.7 Ma-f)of water per year Equivalent to 1/3 Iran’s annual grain harvest Mashad Villages Abandoned

71 percent drop in wheat harvest from a high of 4.1 million tons in 1992 to 1.2 million tons in 2005, Saudi farmers are now pumping water from wells that are 4,000 feet deep Paleowater 35,000 years old Qa-Disi Aquifer

water extraction exceeds the annual recharge by a factor of five, Yemen pumped dry by 2010 Options: relocate the capital pipelines Water table dropping 6 meters (18 ft) per year

Other Large Deficits India China Pakistan ½ the world’s total use of groundwater for agriculture Pumping: 325 million acre feet Recharge: 205 million acre feet Deficit: 120 million acre feet 1 acre-foot = 325,851 gallons Area = 1 acre 1 foot

Deep wells must reach more than half a mile to tap fresh water Level of the deep aquifer is dropping nearly 3 meters (10 feet) per year Deficit feeds 100 million people Shallow, unconfined aquifer depleted

water table falling by 20 feet per year Deficit feeds 200 million 21 million wells Failure of 246 surface irrigation projects $600 electric pumps (1% of GDP) Deficit of 80 million acre-feet India 95 %

5 acres of land Pumps 3200 gallons/hr Irrigates alfalfa for 64 hours 24 times per year Yield: 6.5 gallons milk/day 4.9 million gallons => 2400 gallons milk (2000 gallons water/ gallon milk) 4.9 million gallons water/yr

United States

1/3 of irrigation water comes from groundwater The 3 largest aquifers are in arid/semi-arid regions Ogallala AquiferMidwest Central Valley AquiferCalifornia Southwest Aquifer SystemArizona, Utah, Nevada

Central Valley Aquifer (California) Pumping 15% more water than is replaced Southwest Aquifer (Utah, Nevada, Arizona) Pumping 50% more water than is replaced Deficit of 30 million acre-feet Water storage capacity has declined by 50% High Plains Aquifer (Ogallala) ¼ gone in areas of Texas, Oklahoma, Kansas Water table declines up to 100 feet in some areas

Phoenix Arizona Growing 2 acres/hr Among the highest water users

tripled in population over the last 40 years Tucson

Canal 335 miles long 44 billion gallons/yr 7% lost to evaporation Central Arizona Project

Use, Overuse, Quality

USTs Landfills Septic systems Urban Runoff Agriculture Industry Rainfall Contaminant Sources

Natural Groundwater Contaminants

Tapping water as deep as 1,000 meters water table falling by 20 feet per year 21 million wells India

Deeper Wells and Fluoride Naturally occurring element in Granite which dissolves into the groundwater Water near the surface is generally unaffected Lowering water tables = deeper wells Deep groundwater contains high fluoride levels fluoride in water can be a cumulative poison

Intentional Fluoridation of Water in the U.S. Fluoridation became an official policy of the U.S. Public Health Service in By 1960 water fluoridation had become widely used in the U.S. reaching about 50 million people. By 2006, 69.2% of the U.S. population on public water systems were receiving fluoridated water.

How does it work? Tooth enamel is made of a mineral called hydroxyapatite Ca 5 (PO 4 ) 3 OH Hydroxyapatite is subject to dissolution by acids (H + ) Fluoridation changes the chemical composition of hydroxyapatite to a crystal less subject to acid dissolution Bacteria in the mouth create acids (H + )

Ca 5 (PO 4 ) 3 Sodium fluorosilicate (Na 2 SiF 6 ) Sodium fluoride (NaF) NaFNa + + F - OH Ingestion of fluoridated water increases the F - concentration in saliva F - replaces OH in hydroxyapatite making fluoroapatite F-F- Fluoroapatite is less soluble in acid than hydroxyapatite

Fluoride concentrations In U.S. tap water 0.6 – 1.1 mg/L Lower values in warm climates

1.6 to 6.6 mg/day Colorado Brown Stain Dental Fluorosis Intake: Permissible fluoride limit in India is 1.2 mg/L Fluoride levels between 5-25 mg/L have been found Fluoride levels > 1.5 mg/L

9 mg/day to 12 mg/day Fluorosis has risen from 1 million to 25 million and now to 60 million people in India. Skeletal Fluorosis Intake Fluoride levels > 10 mg/L

Groundwater and Arsenic

Arsenic is Naturally Occurring occurs primarily in association with sulfur-containing minerals mean values of arsenic content in soils, the earth’s crust, and sediments are between 1.5, and 7.7 mg/kg Mobilization of arsenic in the environment arises from anthropogenic activities related to mining and ore processing, metallurgy, agriculture, wood preservation, and industry. Natural waters, in general, contain low levels of total arsenic

Inorganic Forms of Arsenic AsO 4 -3 AsO 3 -3 ArseniteArsenate Low Oxygen High Oxygen Arsenite is more toxic than arsenate, interfering with enzyme activities which catalyze metabolic reactions Arsenite compounds are also more mobile in the environment due to higher solubility compared to arsenate compounds Both arsenate and arsenite are chronic accumulative toxins

“The World’s Largest Mass Poisoning”

Bangladesh and W. India ranked among the world's 10 poorest countries

Accumulation of thick muds in the floodplains and deltas Floodplain and Delta of the Ganges and Brahmaputra Rivers. Floodplain: area paralleling a river that is periodically inundated Deltas are formed from the deposition of sediment carried by the river as the flow leaves the mouth of the river Himalayas Ganges-Brahmaputra Delta

Prior to 1970s One of the highest infant mortality rates in the world Principally due to waterborne disease. Ineffective water and sewage systems Periodic monsoons and floods cholera, dysentery water-borne pathogens Deaths Due to Surface water contamination: 250,000/yr

The Solution: Tap groundwater resources easy inexpensive First 1 million were sunk with aid from World Governments UNICEF World Bank

12 million hand-operated tube wells deliver water to over 80% of the rural village population Infant mortality and diarrheal illness reduced by 50%

Wells in Floodplain and Delta Sediments Water Bearing Muds Natural erosion of arsenic to water- bearing units. Well depths between 20m and 100 m

Majority of wells > 50 ppb arsenic Some wells contain ppb WHO/U.S limit: 10 ppb Bangladesh limit: 50 ppb

Exposure Estimates Above 50 ppb:35 million Above 10 ppb:57 million Early Symptoms: Skin lesions and thickening Strong skin pigmentation

2003 Studies

83 million people Bihar: 40% wells contaminated

Red River Delta 11 million people First wells sunk 7 years ago

End Lecture 17

Next: Florida’s Aquifers

Sea Levels Temporary reestablishment of carbonate deposition

Vulnerability One gallon of gasoline can contaminate 1 million gallons of drinking water 1 ppm

Metals Nutrients Pesticides Petroleum Solvents