Transcript Powerpoint
Why we should be worried about our water
Lily Clark
ENVR 230
November 6, 2007
Drinking Water in the U.S.:
Overview
Overall, water quality has improved over the last 15 years,
according to a report done by the Natural Resources
Defense Council (NRDC)
Quality of tap water varies greatly from city to city
Most cities have good or mediocre water quality
NRDC estimates that 50 million Americans drink water
that is below the standards for water quality set by the EPA
(1996)
CDC estimates that half of the country’s water treatment
systems fail to remove the parasite that killed 100 people in
Milwaukee in 1993 (1996)
Contaminants enter water in many ways, such as through
runoff from sewage systems, runoff from roads and farms,
and dumping of industrial waste
Regulation
EPA has National Primary Drinking Water Regulations
(NPDWRs) to enforce standards for public water systems
Clean Water Act (CWA) of 1972 and Safe Drinking Water
Act (SDWA) of 1974 passed “to restore and maintain the
chemical, physical and biological integrity of the nation’s
waters”
Safe Drinking Water Act Amendments of 1996 introduced
new prevention approaches, changes in regulation, increased
funding to state and local governments and improved
consumer information
CDC performs and funds research and helps disseminate
information regarding safe drinking water
Maximum Contaminant Levels (MCLs)
Microorganisms
Cryptosporidium
Giardia
Legionella
Coliforms (including E. coli)
Turbidity
Enteric viruses
Disinfectants – chlorine and chloramines
Disinfection by-products – chlorite, haloacetic acids,
trihalomethanes
Inorganic chemicals – arsenic, cyanide, fluoride, lead, mercury
Organic chemicals – atrazine, carbon tetrachloride, TCDD, PCBs
Radionuclides
Problems with Regulation
Report by the General Accounting Office in 1993 found that
“most state inspection programs to ensure the safety of
public water supplies are a shambles”
State public health departments responsible for monitoring
and reporting to the EPA on water quality
However, many state inspection programs are under funded
and are thus unable to test the water every three years, as
recommended by the EPA
Deficiencies often went unidentified and uncorrected due to
bad record-keeping
Less than half of the inspectors nationwide had been formally
trained
Lapse in regulation seen in DC lead contamination and the
disease outbreak in Milwaukee
Health Effects
Lead
Permanent brain damage and decreased intellectual
ability in infants and children
Trihalomethanes and haloacetic acids
Cancer and reproductive problems, including
miscarriage
All possible health effects especially dangerous for
those with a compromised immune system
Pregnant women, infants, children, elderly, HIV/AIDS
patients, chemotherapy and cancer patients
Health Effects of Waterborne
Pathogens
Especially dangerous for the immuno-compromised
(HIV/AIDS, the elderly, children, chemo patients)
Cause diarrhea and acute gastrointestinal illness (AGI)
Currently estimated 4.26 – 11.69 million cases of AGI
annually
Due to drinking water from community drinking water
systems supplied by surface and groundwater sources
However, most of the microbes that have caused
outbreaks of waterborne diarrheal illnesses in the U.S.
and their sources are unidentified
Threats to Water Quality
Reliance on pipes that are 100 years old, on average
Problems with breakage
Leach contaminants and allow bacteria to breed
Reliance on outdated water treatment techniques
Regulatory efforts by the Bush administration
Weaken regulation on source waters
Stall the creation of new standards for contaminants
Cut funding and environmental programs
How the Bush Administration’s Policies
Threaten Our Drinking Water
Bush administration policies in 2003 supported reducing the
protection of our water sources and our drinking water
Specifically, proposed scalebacks would have removed protection
for headwaters, wetlands, seasonal streams and other water
sources
Policy would exempt protections on “isolated” waters
These exemptions would have affected directly the drinking water
sources for 15 U.S. cities, including Atlanta, Baltimore, D.C. and
Seattle
Policy rejected in 2006
In 2006, the Bush administration declared that federal workers
would not be protected under whistleblower protection for
reporting “water enforcement breakdowns, manipulations of
science, or cleanup failures”
Threatens the integrity of the CWA and SDWA by removing
protection from federal employees who attempt to uncover and
report honestly the state of our water quality
What’s On Tap: Grading Drinking
Water in U.S. Cities
The Natural Resources Defense Council issued a 2003
report on the quality of drinking water in 19 states
City
Water Quality &
Compliance
Right To Know
Source Water
Protection
Albuquerque
Poor
Good
Poor
Atlanta
Fair
Fair
Poor
Baltimore
Good
Good
Fair
Boston
Poor
Poor
Good
Chicago
Excellent
Good
Fair
Denver
Good
Good
Good
Detroit
Good
Good
Poor
Fresno
Poor
Poor
Failing
Houston
Fair
Fair
Poor
Los Angeles
Fair
Good
Poor (import)
Fair (local)
Manchester
Good
Good
Good
New Orleans
Good
Good
Poor
Newark
Fair
Failing
Fair
Philadelphia
Fair
Good
Poor
Phoenix
Poor
Failing
Poor
San Diego
Fair
Fair
Poor (import)
Fair (local)
San Francisco
Poor
Fair
Good
Seattle
Fair
Fair
Excellent
Washington, D.C.
Fair
Fair
Fair
Process of Water Treatment
Coagulation – addition of aluminum sulfate to make large particles of
solids stick together
Perchlorination (optional) – addition of chlorine or other oxidant to
start disinfection and oxidation of chemicals
If added at this early stage, can greatly increase levels of by-products
Sedimentation – water mixed and left to sit to allow coagulant to take
effect
Filtration – run water through filters of sand or coal to remove smaller
particles (unable to remove arsenic, pesticides and other chemicals)
Primary chemical disinfection – usually chlorine gas or liquid
Corrosion inhibitor – lime or zinc orthophosphate to inhibit ability of
water to corrode city and household piping
Fluoride and secondary disinfection – second dose of infectant to
prevent recontamination
Waterborne Pathogens
Vegetative bacteria and other microorganisms are killed by
disinfection process of water treatment
Cryptosporidium and Giardia are relatively resistant to
disinfection process
Many waterborne parasites are resistant to chlorination
Filtration removes these parasites, however many treatment
facilities have broken and failing filtration systems
Acute gastroenteritis illness (AGI) is most common health
problem associated with consumption of water
contaminated with microbes
Associations between water turbidity and AGI have been
found in citywide studies performed in Milwaukee and
Philadelphia
AGI rates in the US can be used to estimate the risk of
infectious, waterborne diseases
Waterborne Disease Outbreaks
(WBDOs)
Outbreak statistics do not accurately reflect the incidences of
waterborne illness due to endemic contamination
There is no surveillance system to report the incidences of endemic
waterborne illness, specifically AGI, in the US
Reported occurrences of WBDOs are only a fraction of the actual
occurrences of AGI because endemic illnesses are not included
WBDO statistics have been recorded since the 1920s through
local, state and national public health departments
Useful to identify risks of disease associated with source waters,
public water systems and treatments
Also provide information about the important waterborne
pathogens and adequacy of contamination regulations
Disease Outbreaks
Waterborne pathogens are increasing as a cause of
waterborne disease outbreaks in the U.S.
Between 1991 and 2002
403,000 people got sick
4,400 were hospitalized
50 died
Mortality associated with WBDOs decreased from 1920 to
1990 but has risen in the last 12 years
The percentage of WBDOs associated with contaminants
in the public water systems have increased since 1991
Outbreak tracking does not take into account rates of
endemic waterborne diseases, which can be caused by the
same pathogens
Taken from Craun et al. “Waterborne outbreaks reported in the United States.” Journal of
Water and Health. 2006.
Etiology of waterborne outbreaks reported in the U.S., 1991 –
2002
Etiological agent
Outbreaks
Cases
AGI
77
16,036
Chemical
33
577
Giardia
25
2,283
Cryptosporidium
15
408,371
Norovirus
12
3,361
E. coli O157:H7
11
288
Shigella
9
663
Campylobacter jejuni
7
360
Legionella
6
80
Salmonella
3
833
V. cholerae
2
114
Hepatitis A
2
56
Naegleria fowleri
1
2
Plesiomonas shigelloides
1
60
Campylobacter and Yersinia
1
12
E. coli O157:H7 & Campylobacter
1
781
Unidentified SRSV
1
70
Total
207
433,947
Taken from M. F. Craun et al. “Waterborne outbreaks reported in the United States.” Journal of Water and Health. 04.Suppl
2. 2006.
Milwaukee, 1993
400,000 people got sick and 100 died from
contaminated water
Cryptosporidium was the parasite found in the water
Caused death mostly in immuno-compromised
populations, specifically those with HIV/AIDS
New York, 1999
1,000 people got sick at a county fair in upstate New
York
The water was contaminated with a virulent strain of
E. coli
Resulted in the death of one elderly man and one 3year old girl
New York, 2005
Nearly 750 people got sick from a contaminated play
area in a water park
The water was found to be contaminated with
cryptosporidium
The tank from which the water park drew its water had
a chlorination and a filtration system
U.S. Public Interest Research Group
2005 Report on CWA Compliance
3600, or 57%, of the nation’s water treatment facilities
exceeded limits set by the CWA at least once in 2005
Noncompliant facilities reported 24,400 cases of exceeding
CWA permits
Indicates that facilities are exceeding their permits more than
once, and for more than one pollutant
628 facilities exceeded their permit limits for at least half of
the monthly reporting periods in 2005
On average, noncompliant facilities exceeded permit limits
by four times the allowed amount
On 1800 occasions, facilities reported exceeding the limits
by at least six-fold
Recommended Actions by the Natural
Resources Defense Council
Investment in upgrading water systems
Pipe breaks
Allow in bacteria and contaminants
Estimated $500 billion over the next two decades to ensure
the safety of drinking water nationwide
Upgrading of water treatment techniques
Currently use same basic water treatment technologies from
before WWI
New technologies available – ozone, UV light treatment,
membrane treatment, granulated activated carbon
Use a combination of two or more to maximize efficiency and
minimize by-products of treatment
Strengthen and enforce existing health standards and
create new standards for unregulated contaminants
Sources
EPA
CDC
Healthy Drinking Water: http://www.cdc.gov/Ncidod/dpd/healthywater/index.htm
“Surveillance for Waterborne-Disease Outbreaks --- United States, 1999-2000”:
http://www.cdc.gov/MMWR/preview/mmwrhtml/ss5108a1.htm
Natural Resources Defense Council
“Study Finds Safety of Drinking Water in U.S. Cities at Risk”: http://www.nrdc.org/water/drinking/uscities.asp
“What’s on Tap? Grading Drinking Water in U.S. Cities”: http://www.nrdc.org/water/drinking/uscities/contents.asp
“Limiting Clean Water Act Protection Could Contaminate Drinking Water”:
http://www.nrdc.org/media/pressReleases/030611a.asp
“Clean Water at Risk”: http://www.nrdc.org/water/pollution/cwa30/contents.asp
CNN
“Milwaukee learned its water lesson, but many other cities haven’t”:
http://www.cnn.com/HEALTH/9609/02/nfm/water.quality/
“1,800 infected; water park blamed”: http://www.cnn.com/2005/US/08/19/water.illness/index.html
New York Times
“Outbreak of Disease in Milwaukee Undercuts Confidence in Water”:
http://query.nytimes.com/gst/fullpage.html?res=9F0CE6D9143EF933A15757C0A965958260
“Nearly 750 Are Sickened at State Park”: http://www.nytimes.com/2005/08/19/nyregion/19sick.html
New York Department of Health
http://www.health.state.ny.us/press/releases/2000/ecoli.htm
US PIRG
“Troubled Waters: An analysis of 2005 Clean Water Act compliance”: http://static.uspirg.org/reports.asp?id2=35946
Stormwater Authority: http://www.stormwaterauthority.org/library/view_article.aspx?id=633
Earthjustice:
http://www.earthjustice.org/our_work/policy/2004/bush_administration_launches_effort_to_dismantle_clean_water_act.html
Office of Water: http://www.epa.gov/OW/
Health and Environmental Effects Research Laboratory: http://www.epa.gov/nheerl/articles/2006/waterborne_disease.html
“Clinton Administration works to help protect the public health from recent infectious disease outbreaks.”:
http://yosemite.epa.gov/opa/admpress.nsf/a21708abb48b5a9785257359003f0231/52a4c3f2c4d50b31852567ee00661941!OpenDoc
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