PracticeVideosBlogFlashcardsEspañol
All Practice Exams

100+ Free AZ ROC A-16 Waterworks Practice Questions

Prepare for the Arizona ROC A-16 Waterworks (Commercial) Examination exam with instant access — no signup required.

✓ No registration✓ No credit card✓ No hidden fees✓ Start practicing immediately
Not published Pass Rate
100+ Questions
100% Free

Loading practice questions...

Same family resources

Explore More Arizona Registrar of Contractors Trade Examinations

Continue into nearby exams from the same family. Each card keeps practice questions, study guides, flashcards, videos, and articles in one place.

Arizona ROC A (KA) Dual Engineering Examination

Practice Questions

Arizona ROC A General Engineering (Commercial) Examination

Practice Questions

Arizona ROC A-11/CR-17/R-17 Steel and Aluminum Erection Examination

Practice Questions

Arizona ROC A-12/CR-80 Sewers, Drains and Pipe Laying Examination

Practice Questions

Arizona ROC A-14 Asphalt Paving Examination

Practice Questions

Arizona ROC A-15 Seal Coating Examination

Practice Questions
2026 Statistics

Key Facts: AZ ROC A-16 Waterworks Exam

$66

Exam Fee

PSI / AZ ROC Bulletin

50 Questions

Official Scored Items

PSI A-16 Content Outline

120 Minutes

Time Allowed

PSI A-16 Content Outline

70%

Passing Grade

PSI A-16 Content Outline

Computerized Open-Book

Delivery Method

PSI Services LLC

Prepare for the official Arizona ROC A-16 Waterworks (Commercial) examination with 100 practice questions matching the official PSI blueprint. The official test features 50 scored multiple-choice questions, a 120-minute time limit, open-book book navigation, and a 70% passing threshold ($66 fee). Note: local practice MCQs are an English-language study adaptation designed to hone trade knowledge and code lookup capability.

Sample AZ ROC A-16 Waterworks Practice Questions

Try these sample questions to test your AZ ROC A-16 Waterworks exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 100+ question experience with AI tutoring.

1When assembling a push-on joint for Ductile Iron Pipe (DIP) in a water distribution main per AWWA C600, which procedure is required to ensure a watertight seal without damaging the rubber gasket?
A.Clean the socket and gasket groove, apply approved non-toxic vegetable lubricant to the spigot and gasket, and align pipe before pushing home
B.Apply petroleum-based grease liberally to the gasket and spigot end
C.Heat the bell end with a propane torch to expand the socket prior to inserting the spigot
D.Drive the spigot home using a backhoe bucket directly against the pipe bell without alignment
Explanation: AWWA C600 specifies that the bell socket and gasket groove must be thoroughly cleaned of dirt and debris. An approved non-toxic, NSF/ANSI 61 certified vegetable-based lubricant is applied to the spigot end and gasket surface. The pipe must be aligned straight before pushing the spigot home to avoid dislodging or fish-mouthing the gasket.
2According to AWWA C600 standards, what is the minimum hydrostatic test pressure and duration required for newly installed ductile iron water mains?
A.1.0 times the working pressure for 30 minutes
B.1.5 times the working pressure at the lowest point (or at least 150 psi) for a minimum duration of 2 hours
C.1.25 times the maximum operating pressure for 1 hour
D.2.0 times the system design pressure for 24 hours
Explanation: AWWA C600 requires that newly installed water mains undergo a hydrostatic pressure test at 1.5 times the working pressure measured at the lowest point of the test section, or at least 150 psi (whichever is greater), maintained for a minimum of 2 hours.
3A contractor is hydrostatically testing a 2,000-foot section of 12-inch nominal diameter ductile iron pipe at a test pressure of 150 psi. Using the AWWA C600 allowable leakage formula L = (S * D * sqrt(P)) / 148,000, what is the maximum allowable leakage rate in gallons per hour (gph)?
A.0.98 gph
B.3.45 gph
C.1.99 gph
D.5.20 gph
Explanation: Using AWWA C600 formula L = (S * D * sqrt(P)) / 148,000 where S = 2,000 ft, D = 12 inches, and P = 150 psi: sqrt(150) = 12.2474. L = (2,000 * 12 * 12.2474) / 148,000 = 293,938 / 148,000 = 1.986 gph, which rounds to 1.99 gph.
4A 16-inch water main operating at 100 psi makes a 45-degree horizontal bend. If the total hydrostatic thrust force generated is calculated as 15,400 lbs and the soil bearing capacity is 2,000 pounds per square foot (psf), what is the minimum required bearing area of the concrete thrust block against undisturbed soil?
A.3.85 sq ft
B.30.80 sq ft
C.15.40 sq ft
D.7.70 sq ft
Explanation: Required thrust block surface area against undisturbed trench wall = Total Thrust Force / Soil Bearing Capacity. Area = 15,400 lbs / 2,000 psf = 7.70 square feet.
5In hydraulic network calculations, how does the Hazen-Williams roughness coefficient (C-factor) affect pipe friction head loss?
A.A higher C-factor represents a smoother interior pipe surface, resulting in lower friction head loss
B.A higher C-factor represents a rougher interior surface, resulting in higher friction head loss
C.The C-factor only applies to open-channel flow and has no effect on pressurized pipes
D.Friction head loss is directly proportional to the square of the C-factor
Explanation: The Hazen-Williams C-factor indicates pipe interior smoothness. Higher numbers (e.g., C=140 for new DIP or PVC) indicate smoother pipe walls with less friction loss, whereas lower numbers (e.g., C=100 for aged unlined cast iron) indicate higher head loss.
6What is the continuous pressure rating for AWWA C900 PVC pipe designated as SDR 18 when evaluated with a hydrostatic design basis (HDB) of 4,000 psi?
A.150 psi
B.235 psi
C.200 psi
D.305 psi
Explanation: Per AWWA C900, the pressure class (PC) formula for PVC pipe is PC = (2 * HDS) / (SDR - 1), where Hydrostatic Design Stress (HDS) = HDB / 2 = 2,000 psi. PC = (2 * 2,000) / (18 - 1) = 4,000 / 17 = 235 psi.
7What is the required heater plate surface temperature range for making butt-fusion joints on High-Density Polyethylene (HDPE) water mains per ASTM F2620?
A.250°F to 300°F
B.325°F to 375°F
C.400°F to 450°F
D.500°F to 550°F
Explanation: ASTM F2620 specifies that the heating tool surface temperature for HDPE butt fusion must be maintained within 400°F to 450°F (204°C to 232°C) to ensure proper melt depth without degrading the polyethylene resin.
8When performing main disinfection using the continuous-feed method under AWWA C651, what initial chlorine concentration must be introduced, and what minimum free chlorine residual must remain after 24 hours?
A.10 mg/L initial, 2 mg/L residual
B.25 mg/L initial, 10 mg/L residual
C.100 mg/L initial, 50 mg/L residual
D.50 mg/L initial, 25 mg/L residual
Explanation: AWWA C651 continuous-feed method requires introducing chlorinated water to achieve an initial concentration of at least 50 mg/L throughout the line. After holding for 24 hours, the free chlorine residual must not be less than 25 mg/L.
9Under AWWA C651, what chlorine concentration and minimum contact time are required when using the slug method for main disinfection?
A.100 mg/L for 3 hours
B.50 mg/L for 6 hours
C.25 mg/L for 12 hours
D.200 mg/L for 30 minutes
Explanation: The slug method involves moving a continuous column (slug) of highly chlorinated water containing at least 100 mg/L of free chlorine along the pipe so that all internal surfaces are exposed to the slug for a minimum contact time of 3 hours.
10Which restriction applies to the use of the tablet method for main disinfection under AWWA C651?
A.It can be used on mains of any diameter up to 48 inches regardless of water cleanliness
B.It is restricted to mains 24 inches in diameter or smaller and requires clean, dry pipe conditions during laying
C.Tablets must be dissolved in petroleum distillate prior to attachment to pipe crowns
D.It requires flushing the main at 10 ft/s before introducing water to fill the pipe
Explanation: The tablet method attaches calcium hypochlorite tablets to the inside top of pipe joints during construction. It is restricted to mains 24 inches in diameter or smaller, and can only be used if the trench is dry and pipe interiors remain clean during installation.

About the AZ ROC A-16 Waterworks Exam

The Arizona ROC A-16 Waterworks (Commercial) examination is an open-book trade test administered by PSI Services LLC on behalf of the Arizona Registrar of Contractors. The exam tests commercial contractor expertise in building, altering, and repairing water utility infrastructure. Key content areas include water distribution main lines, water wells and development, excavation and trench backfilling, pump installations and control electrical, water storage tanks, drinking water treatment and disinfection, concrete thrust restraint and foundations, and OSHA safety standards.

Assessment

50 scored multiple-choice questions administered in a 120-minute open-book computer exam at PSI testing centers.

Time Limit

120 minutes

Passing Score

70%

Exam Fee

$66 (Arizona ROC / PSI Services LLC)

AZ ROC A-16 Waterworks Exam Content Outline

24%

Water Distribution Systems

Installation, mains, pipe materials (DIP, PVC, HDPE), valves, hydrants, hydrostatic testing, disinfection, thrust restraint, and Hazen-Williams head loss.

16%

Water Wells

Drilling methods, casing, screening, annular grouting, well development, drawdown testing, sanitary seals, and ADEQ well construction standards.

12%

Excavation and Backfill

Trenching safety, OSHA Soil Type classification (A, B, C), protective shoring/shielding, bedding materials, lift compaction, and pipe backfilling.

12%

Pumps and Related Electrical

Centrifugal and submersible pumps, TDH, NPSH, affinity laws, motor starters, 3-phase wiring, control panels, and electrical grounding.

12%

Water Storage Tanks

Elevated and ground storage tanks, steel/concrete construction, cathodic protection, overflow/venting rules, disinfection, and AWWA D100/D102.

8%

Water Treatment

Disinfection, chlorination math (dosage, demand, residual), filtration, coagulation/flocculation, softeners, backflow prevention (RPZ), and ADEQ drinking water rules.

8%

Concrete

Formwork, reinforcement (rebar/mesh), mix proportioning, water-cement ratio, placement, curing, compressive strength, and thrust block sizing.

8%

Safety

OSHA 29 CFR 1926 safety regulations, PPE, hazard communication, confined space entry in wet wells/tanks, fall protection, and lockout/tagout (LOTO).

How to Pass the AZ ROC A-16 Waterworks Exam

What You Need to Know

  • Passing score: 70%
  • Assessment: 50 scored multiple-choice questions administered in a 120-minute open-book computer exam at PSI testing centers.
  • Time limit: 120 minutes
  • Exam fee: $66

Keys to Passing

  • Work through all 100 available questions
  • Review every answer and explanation
  • Track weak areas and revisit them
  • Use our AI tutor for tough concepts

AZ ROC A-16 Waterworks Study Tips from Top Performers

1Practice hydrostatic pressure testing calculations per AWWA C600, including allowable leakage rates based on pipe diameter and test pressure.
2Memorize OSHA 1926 Subpart P trenching requirements: egress ramps every 25 lateral feet in trenches 4+ ft deep, and protective systems required at 5+ ft depth.
3Master pump hydraulics and affinity laws: power required is proportional to flow times total dynamic head (TDH) divided by pump and motor efficiency.
4Understand ADEQ Bulletin 10 standards for water well sanitary seals and minimum 20-foot annular casing grouting depth.
5Learn chlorination chemical dosage calculations using the formula: Pounds per Day = Flow (MGD) x Dosage (mg/L) x 8.34.

Frequently Asked Questions

What work is authorized under the Arizona ROC A-16 Waterworks license?

The A-16 Waterworks classification permits commercial contractors to construct, alter, or repair water utility lines, water mains, storage tanks, pumping stations, water treatment plants, water wells, and associated concrete, excavation, and electrical control systems.

How many questions are on the official AZ ROC A-16 exam and what is the passing score?

The official PSI trade exam consists of 50 scored multiple-choice questions with a 120-minute (2 hours) time limit. Candidates must achieve a score of at least 70% (35 out of 50) to pass.

Is the AZ ROC A-16 exam open book?

Yes, the trade exam is administered as an open-book test at PSI centers. Approved reference manuals, including AWWA standards, OSHA 1926 regulations, ADEQ engineering bulletins, and concrete handbooks may be brought into the testing site.

What trade experience is required to qualify for the A-16 license?

The Arizona Registrar of Contractors requires the designated qualifying party to document 4 years of verifiable commercial trade experience in waterworks utility construction.

Does taking this practice question bank replace the official exam?

No. These 100 practice multiple-choice questions serve as an English-language study adaptation to help candidates master code navigation, calculations, and technical trade principles required for PSI exam success.