Introduction
Assoc. Prof. Kozet YAPSAKLI
Types of water
Rain water
Storm water
River water/ Lake water
Groundwater
Ocean water
Industrial water
Drinking water
Agricultural water
Irrigation water
Brown water
Yellow water
Grey water
Sewage etc.
HOW DO THEY APPEAR?
Blue water = seems as if good quality water
HOW DO THEY APPEAR?
Green water = seems as if nutrient-enriched water
HOW DO THEY APPEAR
Brown water comes from swamps & forests
Water pollution from poor land use practices
Algal bloom – sign of eutrophication
Choosing Water resources – Starting point of
WQ interventions
Water Quality - How good is it?
Affordability - What does it cost?
Adequacy – Can it supply enough water?
Reliability - How long will it last?
Convenience - How far away is it from homesteads?
TYPES OF DRINKING WATER STANDARDS
PRIMARY
health related
enforced
9
TYPES OF DRINKING WATER STANDARDS
SECONDARY
non-health related contaminants that affect flavor, odor,
color
iron
manganese
sulfate
hydrogen sulfide
chloride
recommended but not enforced
10
Abundance of Dissolved Constituents in
Surface and Ground Water
Major Constituents
(> 5 mg/L)
Ca
Mg
Na
Cl
Si
SO42- - sulfate
H2CO3 - carbonic acid
HCO3- - bicarbonate
Abundance of Dissolved Constituents
in Surface and Ground Water
Minor Constituents
(0.01-10 mg/L)
B
K
F
Sr
Fe
CO32- - carbonate
NO3- - nitrate
Abundance of Dissolved Constituents
in Surface and Ground Water
Trace Constituents
(< 0.1 mg/l) Pb
Al Mn
As Ni
Ba
Se
Br
Ag
Cd
Co Zn
Cu others
Drinking Water Standards
Pollutants/Contaminants Regulated
Microorganisms, Disinfectants & Disinfectant
Byproducts, Inorganic Chemicals, Organic Chemicals,
Radionuclides
Lists available at:
http://www.epa.gov/safewater/contaminants/index.htm
l
KINDS OF HEALTH RELATED
STANDARDS
Maximum Contamination Levels Goals (MCLG's)
Level at which there are no known or anticipated adverse
health effects.
non-enforceable
set at 0 for known carcinogens
15
KINDS OF HEALTH RELATED
STANDARDS
Maximum Contamination Level (MCL's)
set as close to the MCLG as is technically and economically
feasible
enforceable
16
KINDS OF HEALTH RELATED
STANDARDS
Non-regulatory Health Advisory (HA's)
Informal technical guidance regarding concentrations of
drinking water contaminants at which adverse health effects
would not be anticipated to occur
non-regulatory purposes
guidance to state and local officials when emergency
conditions occur
17
Drinking Water Health Advisories
(HA)
Lifetime HA: The concentration of a chemical in
drinking water that is not expected to cause any
adverse noncarcinogenic effects over a lifetime of
exposure, with a margin of safety.
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Dose-Response Curves
100
90
80
70
Response
60
50
40
30
NOAEL
20
RfD
10
0
0 20 40 60 80 100
19
Dose Rate (mg/kg/day)
Drinking Water Standards (EPA, May
1995)
A. Chemical
1. Maximum Contaminant Level (mg/ L)
lead .015
mercury .002
nitrate (as N) 10.0
nitrite (as N) 1.0
alachlor (lasso) 0.002
aldicarb 0.007
atrazine 0.003
carbofuran (Furadan) 0.04
20
Drinking Water Standards (EPA, May
1995)
2. Secondary Maximum Contaminant
Level (mg/ L)
chloride 250
copper 1
iron 0.3
pH 6.5 to 8.5
sulfate 250
total dissolved solids (TDS) 500
21
Drinking Water Standards (EPA, May
1995)
B. Physical
color 15 color
units
odor 3 odor
units
C. Bacteriological
coliform bacteria none
22
Water Quality Problem
The MCL for atrazine is 0.003 mg/L. How much atrazine at this
concentration would be in the water in a pond which has a surface
area of 5 acres and an average depth of 8 feet?
23
Water Classification
How?
Compare ions with ions using chemical equivalence
Making sure anions and cations balance
Use of diagrams and models
Why?
Helps define origin of the water
Indicates residence time in the aquifer
Aids in defining the hydrogeology
Defines suitability
What is Chemical Equivalence?
Chemical analysis of groundwater samples
Concentrations of ions are reported by
weight (mg/L)
chemical equivalence (meq/L)
Takes into account ionic charge
Equivalent Concentration
Ion Balance
If all ions are correctly determined by a lab
sum of cations should equal sum of anions (all in meq/L)
Errors in analysis and chemical reactions in samples
5% difference is considered acceptable
> 5%, question the lab results
Calculating Equivalence
Sandstone Aquifer
Parameter
mg/L Meq/L
Na+ 19 0.827
For instance:
Cl- 13 0.367 The atomic wt. of Sodium
SO42- 7 0.146 (valence of one) = 22.989
Ca2+ 88 4,391 And its charge is one
Mg2+ 7.3 0.6 Dividing the concentration of
HCO3- 320 5.245 sodium in the sample (19 mg/L)
by its “combining wt.” = 0.827
Total Anions 5.758 meq/L or its equivalent
Total 5.818 concentration.
Cations
%
1%
Difference
Aquatic Freshwater Protection
Criteria (USA EPA Guidelines)
Criteria Recommended Standard
pH 6.5-9.5
Alkalinity 20 mg/L or more
30 day average 5.5 mg/L
Dissolved Oxygen
(warm water fish)
Should not reduce Photosynthesis
Suspended Solids
by more than 10% in the water
Drinking Water Criteria
(USA EPA Guidelines)
Criteria Recommended Standard Reason
Coliform Bacteria 0 colonies/ml Health
pH 6.5-8.5 Aesthetic
Health
Barium 2 mg/L
Nitrate 10 mg/L Health
Total Dissolved
500 mg/L Taste
Solids
Secondary - Drinking water standards
(EPA)
Contaminant Secondary Standard
Aluminum 0.05 to 0.2 mg/L
Chloride 250 mg/L
Color 15 (color units)
Copper 1.0 mg/L
Corrosivity noncorrosive
Fluoride 2.0 mg/L
Foaming Agents 0.5 mg/L
Iron 0.3 mg/L
Manganese 0.05 mg/L
Odor 3 threshold odor number
pH 6.5-8.5
Silver 0.10 mg/L
Sulfate 250 mg/L
Total Dissolved
500 mg/L
Solids
