AWWA Water Quality Analyst Certification
Exam Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. Which parameter is most commonly used as a general indicator of
water quality in distribution systems?
A. Chloride
B. Turbidity
C. Hardness
D. Fluoride
Answer: B. Turbidity
Rationale: Turbidity indicates the presence of suspended
particles in water. It is widely used as a general indicator of
treatment effectiveness and potential microbial risk.
,2. What is the primary purpose of residual chlorine in drinking water
systems?
A. Increase pH
B. Remove hardness
C. Provide ongoing disinfection
D. Reduce turbidity
Answer: C. Provide ongoing disinfection
Rationale: Chlorine residual ensures continued microbial control
throughout the distribution system after initial treatment.
3. Which organism is commonly used as an indicator of fecal
contamination?
A. Giardia
B. E. coli
C. Legionella
D. Algae
Answer: B. E. coli
Rationale: E. coli is a strong indicator of recent fecal
contamination and potential presence of pathogens.
,4. What does pH measure in water?
A. Dissolved solids
B. Acidity or alkalinity
C. Turbidity
D. Hardness
Answer: B. Acidity or alkalinity
Rationale: pH measures hydrogen ion concentration, indicating
how acidic or basic water is.
5. Which chemical is most commonly used for disinfection in
municipal water systems?
A. Ozone
B. Chlorine
C. Fluoride
D. Alum
Answer: B. Chlorine
Rationale: Chlorine is widely used due to its effectiveness, cost
efficiency, and ability to maintain a residual.
6. What is Total Dissolved Solids (TDS) primarily composed of?
A. Bacteria
, B. Organic matter only
C. Inorganic salts and minerals
D. Suspended particles
Answer: C. Inorganic salts and minerals
Rationale: TDS measures dissolved ions such as calcium,
magnesium, sodium, and chlorides.
7. Which instrument is used to measure turbidity?
A. pH meter
B. Turbidimeter
C. Spectrophotometer
D. Conductivity meter
Answer: B. Turbidimeter
Rationale: A turbidimeter measures light scattering caused by
suspended particles in water.
8. What does conductivity measure in water?
A. pH level
B. Microbial content
C. Ability to conduct electrical current
D. Turbidity
Exam Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. Which parameter is most commonly used as a general indicator of
water quality in distribution systems?
A. Chloride
B. Turbidity
C. Hardness
D. Fluoride
Answer: B. Turbidity
Rationale: Turbidity indicates the presence of suspended
particles in water. It is widely used as a general indicator of
treatment effectiveness and potential microbial risk.
,2. What is the primary purpose of residual chlorine in drinking water
systems?
A. Increase pH
B. Remove hardness
C. Provide ongoing disinfection
D. Reduce turbidity
Answer: C. Provide ongoing disinfection
Rationale: Chlorine residual ensures continued microbial control
throughout the distribution system after initial treatment.
3. Which organism is commonly used as an indicator of fecal
contamination?
A. Giardia
B. E. coli
C. Legionella
D. Algae
Answer: B. E. coli
Rationale: E. coli is a strong indicator of recent fecal
contamination and potential presence of pathogens.
,4. What does pH measure in water?
A. Dissolved solids
B. Acidity or alkalinity
C. Turbidity
D. Hardness
Answer: B. Acidity or alkalinity
Rationale: pH measures hydrogen ion concentration, indicating
how acidic or basic water is.
5. Which chemical is most commonly used for disinfection in
municipal water systems?
A. Ozone
B. Chlorine
C. Fluoride
D. Alum
Answer: B. Chlorine
Rationale: Chlorine is widely used due to its effectiveness, cost
efficiency, and ability to maintain a residual.
6. What is Total Dissolved Solids (TDS) primarily composed of?
A. Bacteria
, B. Organic matter only
C. Inorganic salts and minerals
D. Suspended particles
Answer: C. Inorganic salts and minerals
Rationale: TDS measures dissolved ions such as calcium,
magnesium, sodium, and chlorides.
7. Which instrument is used to measure turbidity?
A. pH meter
B. Turbidimeter
C. Spectrophotometer
D. Conductivity meter
Answer: B. Turbidimeter
Rationale: A turbidimeter measures light scattering caused by
suspended particles in water.
8. What does conductivity measure in water?
A. pH level
B. Microbial content
C. Ability to conduct electrical current
D. Turbidity
