advanced operator short schools water resources cal sawyer/mark anderson
TRANSCRIPT
Advanced OperatorShort Schools
WATER RESOURCES
Cal Sawyer/Mark Anderson
Advanced OperatorShort Schools
Introduction to Water Supply
Public Health Protection
Historical Context
Ancient times– Civilization began near
river valleys Water delivered by
nature
Historical Context (continued)
Water Supply– Quantity and not
quality– Most use for
irrigation, not for drinking
Hand carried
Historical Context (continued)
Little evidence on quality– Knew little about
disease– Treatment used
improved appearance or taste
History of Water Treatment
Distribution (hydraulics)– Roman aqueducts
– Indus Valley
– Irrigation canals
History of Water Treatment Hippocrates stated, “. . . water contributes
much to health,” and asserted rainwater be boiled and strained
Aristotle
History of Water Treatment
1771 first reference made to water filtration– Encyclopedia Brittanica
Slow sand filtrationNot straining-Schmutzdecke
In 1828, Chelsea Waterworks By 1850, use of chlorine bleach In 1852, law in London that all water should be
filtered
Broad Street Well
London outbreak of cholera in 1854– 700 deaths– 17 weeks
Broad Street Well Dr John Snow
conducted 1st epidemiological study
Leaky sewer from original cholera case passed near the well
Mrs. E. and her niece provided clue
Map
Broad Street
Sewage collector
Communicable Diseases
Disease spread by odors Up to the 1850’s (Snow’s work) Transmission by water accepted Although agents not identified yet
Louis Pasteur
1864- Wine 1865- Bacteria
caused disease Vaccines Pasteurization of
milk
Early Epidemiology
Concept that bacteria caused disease not widely accepted until the 1890’s
Work of Professor Sedgwick– Typhoid epidemic in Dec. 1890-1891– Lowell and Lawrence, MA– Form to collect data house to house
Sedgwick’s Study
Merrimack River
Lawrence
Lowell
9 miles
3 miles
Village of N. Chelmsford
Hamburg/Altona Cholera Outbreak
Hamburg
Altona
Death Rate per 100,000
Hamburg 1344
Altona 230
Elbe RiverFiltration Plant
1892
Turn-of-the Century America
36 typhoid fever deaths per 100,000 Typhoid fever deaths:other deaths
– Lawrence 1:4.4– Lowell 1:6– (Hamburg 1:15.8)
Actual Death Rate: 21,235:100,000
Yet, In America . . .
By 1900, less than 10 slow-sand filtration were in the US
Most efforts were in supply and distribution, not treatment
Disrupted by the Civil War Decades of observation on death by
waterborne disease was required before action taken
But Progress was being made
1871: first slow sand filter in US– Poughkeepsie, NY– Richmond, VA (1832)
1896: first rapid filter in US 1890’s: experimentation with chlorination 1908: first waterworks using chlorination
Treatment Effectiveness in Reducing Typhoid Deaths
0
5
10
15
20
25
30
Death
s per
100,0
00
DisinfectionNone Filtration & Disinfection
Detroit, Michigan
Civil Engineering Milestones in US
Early focus on supply, not treatment By 1800, there were 18 waterworks 1842 water begins flowing from Croton
reservoir to NYC via a 95-mgd aqueduct 1848 Cochituate Aqueduct supplies BostonCollection of wastewater and storm water 1855 Chicago begins developing sewage
system
Sanitary Engineering Research Milestones
1887 M.I.T.’s Sanitary Chemistry Lab tasked to analyzed water supplies
1887 Massachusetts Board of Health reorganized to add engineering department
1890 Lawrence Experiment Station demonstrated wastewater treatment to be a biochemical process
Sanitary Engineering Design Milestones
1871 First slow sand filter in Poughkeepsie 1880 Separate sewer systems
recommended 1893 slow sand filters treat Merrimack
River water– Removed 98% bacteria– Deaths from typhoid fever dropped
Bacteriological Examination of Water
1884 Escherich isolated organisms from stool samples thought to cause cholera
Proved the existence of coliform bacteria Recognized as an inherent characteristic of the
feces of man (E. coli)
Early Success in Drinking Water Protection
Typhoid Deaths Per 100,000 People
Waterborne Disease
Current status of waterborne diseases in U.S.– CDC Reports
– Waterborne diseases• Bacterial
• Intestinal parasites
• Viral
Sources– Drinking Water
– Recreational Water
Major microorganisms of health concerns
Bacteria– Salmonella Typhoid fever– Shigellae Shigellosis– Escheria coli
Gastroenteritis– Vibrio cholerae Cholera– Legionella Legionellosis
Major organism (continued)
Enteric viruses– Enteroviruses Gastroenteritis,
polio, aseptic meningitis, heart anomalies
– Rotavirus Gastroenteritis– Hepatitis A Infectious
hepatitis– Norwalk agent Gastroenteritis
Major organisms (continued)
Protozoans– Giardia lamblia Giardiasis– Entamoeba histolytica Amebic dysentery– Cryptosporidium Cryptosporidiosis
Waterborne Disease Outbreak
An incident in which two or more persons experience a similar illness after consumption or use of water intended for drinking and epidemiological evidence implicates the water as the source of the illness.
Waterborne Disease Outbreaks in United States, 1995-1996
STATE ETIOLOGICAGENT
CASES OFILLNESS
New York, Alaska Giardia lamblia 1,459Florida Sodium Hydroxide 30Idaho, Oklahoma Shigella sonnei 93Idaho, Montana,Pennsylvania,South Dakota,Wisconsin, California
Gastroenteritis,undefined
683
Iowa Concentrated LiquidSoap
13
Minnesota E. Coli 0157:h7 33Wisconsin Small Round
Structured Virus148
Wisconsin Copper 37CaliforniaNew Jersey
Nitrate 9e:
Impact of Water Treatment on Health
After reviewing the cause of death in America during the late 1800’s and early 1900’s, the microbiologists Gainey and Lord concluded that:
“The purification of water and pasteurization of milk have saved more lives than all the wonder drugs ever devised.”
Future Concerns
Deteriorating infrastructure At-risk populations Shift is back to microbial contamination Best water sources already tapped-
– 70% earth’s surface is water of which– 3% is fresh of which only– 0.04% is usable
Expanding Demographics
More demand: Capacity Quality
Water Quality
Best sources already used Demand forces the use of poorer quality
sources– Surface sources– Groundwater
Pollution– Point sources– Non-point sources
Our challenge is:
How do we ensure safe drinking water for future generations?
At-risk populations?
Work Smarter
Source water protection
Conservation Education New technology
Summary
Water treatment relatively new (around the turn of the century)
Quantity then quality issues Water treatment can effectively control
outbreaks of waterborne disease
Hydrologic Cycle
Virginia GroundwaterPhysiographic Provinces
Valley and Ridge
Estimated recharge is 8.2 billion gal/dayTotal use = 389 million gal/day (1980)
Coastal Plain
Piedmont
Cumberland Plateau
Blue Ridge
Water Distribution and Availability
40 million cubic miles of water on or in the earth
Oceans = 97%
Fresh Water = 3%- Snow & Ice = 2.25%- Usable Groundwater = 0.3%- Surface Water < 0.5%
Primary Sources of Water
•Captured and stored rainfall in cisterns
•Groundwater from springs, artesian wells, & drilled/dug/bored wells
•Surface water from lakes, rivers, & streams
•Desalinized seawater or brackish groundwater
•Reclaimed water
Virginia’s Surface Water
27,000 miles of streams and rivers 10 major river basins Average discharge about 25 billion gal/day 248 lakes and reservoirs 212,875 acres of wetlands 2,382 square miles of estuaries
Surface Water
Photo Credit: Virginia Department of Health
Surface Water Quality
Widely variable quality:
- Upstream waste discharges
- Flash changes in quality (rivers, streams, small lakes)
- Algae blooms (rivers & lakes)
- Stratification & Turnover (lakes) Must be filtered & disinfected Difficult to protect source
Surface Water Quality
Pollution sourcesRunoff (agriculture, residential, urban)SpillsMunicipal and Industrial wastewater
dischargesRecreational usersNature
Pathways of Contamination
Paths of Water Flow within Watershed
Groundwater Quality
Generally high quality (chemical, bacteriological, and physical properties)
Used without filtration, if not “Under the Direct Influence of Surface Water” (GWUDI)
Used without disinfection if low coliform count
Groundwater Quality Contamination Threats
Failing septic systemsSaltwater intrusionImproper land disposal of wastesLeaking USTsHazardous materials spillsMisapplication of fertilizers and pesticidesImproperly abandoned wellsMiningNaturally occurring constituents
Questions?