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Exam Review

Key Facts: ID Water/WW Operator Exam

70%

Passing Score

Idaho Board of Drinking Water and Wastewater Professionals (DOPL)

Varies

Exam Questions

Idaho Board of Drinking Water and Wastewater Professionals (DOPL)

Varies

Time Limit

Idaho Board of Drinking Water and Wastewater Professionals (DOPL)

100 Q

Practice Questions

OpenExamPrep

Sample ID Water/WW Operator Practice Questions

Try these sample questions to review concepts for the ID Water/WW Operator exam. Each question includes a detailed explanation. Start the interactive quiz above for the full 202+ question experience with AI tutoring.

1Which state agency oversees drinking water and wastewater operator licensing in Idaho?
A.Idaho Department of Environmental Quality
B.Idaho Division of Occupational and Professional Licenses (DOPL), Board of Drinking Water and Wastewater Professionals
C.Idaho Department of Health and Welfare
D.Idaho Water Resources Board
Explanation: The Idaho Board of Drinking Water and Wastewater Professionals, housed within the Division of Occupational and Professional Licenses (DOPL), oversees all operator licensing including exams, applications, and renewals.
2What license types does the Idaho Board of Drinking Water and Wastewater Professionals issue?
A.Only water treatment
B.Drinking water distribution, drinking water treatment, wastewater treatment, wastewater collection, wastewater lab analyst, and backflow assembly tester
C.Only wastewater treatment
D.Only backflow testing
Explanation: Idaho issues licenses in six categories: drinking water distribution operator, drinking water treatment operator, wastewater treatment operator, wastewater collection system operator, wastewater laboratory analyst, and backflow assembly tester.
3What is the minimum passing score for Idaho water and wastewater operator exams?
A.60%
B.65%
C.70%
D.80%
Explanation: Idaho requires a minimum score of 70% to pass licensing examinations for all water and wastewater operator classification levels.
4How many hours of on-site experience does Idaho require for a Class I wastewater treatment operator?
A.260 hours
B.800 hours
C.1,600 hours
D.4,800 hours
Explanation: Idaho requires 1,600 hours of on-site operating experience at a Class I or higher wastewater system. Alternatively, 3,200 hours at a Very Small Wastewater System or completion of an approved apprenticeship qualifies.
5What is an Idaho Class I Restricted wastewater license?
A.A temporary license with no restrictions
B.A system-specific license limited to a particular facility, requiring 260 hours during 12 consecutive months
C.A full unrestricted Class I license
D.A laboratory analyst license
Explanation: Idaho's Class I Restricted license is limited to a specific wastewater system. It requires 260 hours of on-site operating experience during 12 consecutive months.
6How many continuing education hours does Idaho require for license renewal?
A.3 hours
B.6 classroom hours (0.6 CEUs)
C.12 hours
D.24 hours
Explanation: Idaho requires 6 classroom hours (0.6 CEUs) of continuing education germane to the license type during the prior licensing period for renewal.
7Where are Idaho operator licensing exams administered?
A.DOPL office only
B.PSI testing centers (ABC exams via test-takers.psiexams.com/abc-id)
C.Any community college
D.By mail
Explanation: Since July 2023, Idaho exams are taken at PSI testing centers. Applicants visit test-takers.psiexams.com/abc-id to schedule ABC standardized exams and must pass before submitting their license application.
8What experience is required for Idaho Class II wastewater treatment operator?
A.1,600 hours
B.2,400 hours
C.4,800 hours at a Class I or higher system
D.8,000 hours
Explanation: Idaho Class II wastewater treatment requires 4,800 hours of on-site experience at a Class I or higher system, or completion of an approved apprenticeship program.
9What is the primary purpose of coagulation in water treatment?
A.To kill bacteria
B.To neutralize charges on particles so they clump together for removal
C.To remove dissolved gases
D.To adjust pH to 7.0
Explanation: Coagulation adds chemicals like alum or ferric chloride to neutralize electrical charges on colloidal particles. Once neutralized, particles aggregate into larger floc that settles and filters more easily.
10What is breakpoint chlorination?
A.Equipment failure point
B.Adding enough chlorine to satisfy all demands and produce free chlorine residual
C.Maximum chlorine dose before taste complaints
D.Temperature where chlorine changes state
Explanation: Breakpoint chlorination adds enough chlorine to oxidize all ammonia, organic matter, and reducing agents. Beyond this point, additional chlorine remains as free available chlorine for reliable disinfection.

About the ID Water/WW Operator Exam

The Idaho water/wastewater operator certification exam covers state-specific regulations, water treatment processes, wastewater treatment, distribution and collection systems, laboratory testing, safety procedures, and math calculations. Certification levels: Class I, II, I Restricted.

Exam sponsor: Idaho Board of Drinking Water and Wastewater Professionals (DOPL). The requirements and fees below concern the certification or admission exam, separate from our free practice resources.

Questions

100 questions

Time Limit

Varies by certification level

Passing Score

70%

Exam / Certification Fees

Varies

Exam sponsor website

Fees, eligibility, and exam policies can change. Confirm them with the exam sponsor before applying or paying.

Our practice resources: topics covered

We aim to reflect publicly available exam outlines and topic information in our study resources. Coverage, format, and difficulty may differ from the actual exam, and we cannot guarantee that every detail is accurate or current. Confirm exam requirements, fees, and policies with the official exam sponsor.

20%

State Laws & Regulations

Idaho water/wastewater operator licensing requirements, certification levels, and state-specific regulations

25%

Water Treatment

Coagulation, flocculation, filtration, disinfection, chlorination, and treatment math calculations

25%

Wastewater Treatment

Activated sludge, sludge handling, secondary treatment, and biological processes

15%

Distribution & Collection

Pump operations, hydraulics, flow calculations, and system maintenance

15%

Laboratory Testing

Water quality testing, sampling procedures, record-keeping, and regulatory reporting

Preparing for the ID Water/WW Operator Exam

What You Need to Know

  • Passing score: 70%
  • Exam length: 100 questions
  • Time limit: Varies by certification level
  • Exam / certification fees: Varies Official sources

Using Our Practice Resources

  • Work through all 202 available questions
  • Review every answer and explanation
  • Track weak areas and revisit them
  • Use our AI tutor for tough concepts

ID Water/WW Operator: Suggested Study Strategy

1Study Idaho-specific water/wastewater operator licensing requirements and regulatory structure
2Master water treatment processes: coagulation, flocculation, sedimentation, filtration, and disinfection
3Learn activated sludge process parameters: MLSS, SVI, F/M ratio, MCRT, RAS/WAS
4Practice math calculations: chemical dosing (lbs = Flow × Dose × 8.34), detention time, flow rate, and pump calculations
5Review OSHA safety requirements for confined space entry, chlorine handling, and lockout/tagout procedures

Frequently Asked Questions

What certification levels does Idaho offer?

Idaho offers Class I, II, I Restricted certification levels for water and wastewater operators.

What score do I need to pass?

The minimum passing score is 70%. Requirements may vary by certification level.

What are the continuing education requirements?

Idaho requires 6 classroom hours (0.6 CEUs) per renewal for license renewal.