Studying for a Pennsylvania water or wastewater operator exam? You're in the right place. Pick your discipline below: each tab has the certification levels, how Pennsylvania names them, and the practice tests that match.
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Choose your certification
How Pennsylvania classifies drinking-water operators
Pennsylvania does not have a single ladder. DEP's Bureau of Safe Drinking Water certifies on two axes at once, and you need both to legally make a process control decision.
Full breakdown in the FAQ below.
Choose your Pennsylvania class and subclass
Water Class (size of system): Dn and Dc, then D through A
Pennsylvania Class Dc and Dn, Small System Practice Test
Dc covers a groundwater system serving fewer than 500 people or no more than 150 connections that needs only disinfection and is in compliance. Dn is the same thing with no disinfection at all. These are Pennsylvania's smallest special classes.
PA DEP · Class DPennsylvania Class D, Water Operator Practice Test
Class D covers systems of 100,000 gallons per day or less. Remember that the class is only half the picture: you also need a subclassification for each treatment technology you control.
PA DEP · Class CPennsylvania Class C, Water Operator Practice Test
Class C covers systems over 100,000 gpd up to 1 MGD. Your class must be equal to or greater than the size of the system you operate.
PA DEP · Class BPennsylvania Class B, Water Operator Practice Test
Class B covers systems over 1 MGD up to 5 MGD.
PA DEP · Class A (largest)Pennsylvania Class A, Water Operator Practice Test
Class A is the largest class, covering systems over 5 MGD. Class is awarded on your experience, while the subclassifications are awarded on education, exam score and experience combined.
Water Subclasses (treatment technology), the second exam
Pennsylvania wastewater practice tests
Wastewater in Pennsylvania uses the same two-axis scheme as drinking water. The class is size: Class A over 5 MGD, B over 1 up to 5 MGD, C over 100,000 gpd up to 1 MGD, D at 100,000 gpd or less, and Class E for a satellite collection system with a pump station. The subclassification is technology, and wastewater has five: 1 activated sludge, 2 fixed film, 3 treatment ponds and lagoons, 4 single-entity collection system, and 5 laboratory supervisor. For Classes A through D you must pass both the General Exam and a technology-specific subclass exam. Only Class E has a standalone exam. Subclass 5, laboratory supervisor, cannot be held on its own: you must already be certified in wastewater treatment at Class A, B, C or D before you can add it, and it takes two years of hands-on analytical testing experience.
Wastewater Class (size of system): D through A, plus Class E
Pennsylvania Class D, Wastewater Practice Test
Class D covers wastewater systems of 100,000 gallons per day or less. As with drinking water, the class sets the size you may operate and the subclass sets the technology you may control.
PA DEP · Class CPennsylvania Class C, Wastewater Practice Test
Class C covers systems over 100,000 gpd up to 1 MGD.
PA DEP · Class BPennsylvania Class B, Wastewater Practice Test
Class B covers systems over 1 MGD up to 5 MGD.
PA DEP · Class A (largest)Pennsylvania Class A, Wastewater Practice Test
Class A is the largest wastewater class, covering systems over 5 MGD.
Wastewater Subclasses (treatment technology)
Pennsylvania Subclass 1, Activated Sludge Practice Test
Subclass 1 is activated sludge, covering extended aeration, sequencing batch reactors, contact stabilization, conventional, step feed and oxidation ditch.
PA DEP · WW subclass 2-3Pennsylvania Subclasses 2 and 3, Fixed Film and Lagoons
Subclass 2 is fixed film treatment, meaning trickling filters and rotating biological contactors. Subclass 3 is treatment ponds and lagoons, covering aerated, anaerobic, facultative and wetland processes.
Distribution in Pennsylvania is Class E on the water side, defined as distribution and consecutive water systems. Consecutive means a system that buys its water from another system rather than treating its own, so a community that purchases all its water and simply distributes it is operating under Class E. Unlike Classes A through D, Class E is a standalone exam: there is no separate General Exam plus subclass combination to sit. DEP describes these special classifications as covering the non-treatment parts of a system, which is exactly what distribution is.
Pennsylvania Class E, Water Distribution Practice Test
Class E covers distribution and consecutive water systems. Mains, valves, hydrants, storage, disinfection in the system, cross-connection control and sampling.
Extra practicePennsylvania Distribution, Deeper Practice
A second, larger bank on the same Class E material: hydraulics, pumping, storage, water quality in the distribution system, and regulations.
Extra practicePennsylvania Distribution, Advanced Practice
Advanced distribution material for operators at larger systems who also hold a treatment class.
Collection in Pennsylvania is handled through wastewater Subclassification 4, single-entity collection system, defined as a collection system that relies on treatment from a plant owned by the same owner as the collection system. Subclass 4 can be combined with a Class A, B, C or D certification and with the other subclasses. Separately, wastewater Class E covers a satellite collection system with a pump station, and DEP pairs Class E with subclassification 4. So the answer to what a Pennsylvania collection operator needs depends on whether the collection system shares an owner with its treatment plant or runs as a satellite.
Pennsylvania Subclass 4, Collection Systems Entry Practice
Entry collection material for wastewater Subclassification 4: pipe, manholes, basic maintenance, safety and confined space awareness.
PA DEP · WW subclass 4Pennsylvania Subclass 4, Collection Operations Practice
Cleaning and inspection, lift station and pump station operation, infiltration and inflow, and overflow response. Relevant to Class E satellite systems with a pump station.
PA DEP · WW subclass 4Pennsylvania Collection, Senior Level Practice
Pump station hydraulics, force mains, odor and corrosion control, and rehabilitation methods.
PA DEP · WW subclass 4Pennsylvania Collection, Manager Level Practice
Asset management, capacity assurance, capital planning and regulatory reporting for the largest collection systems.
About the Pennsylvania operator exams
Operator certification in Pennsylvania covers several disciplines, drinking water, wastewater, distribution, and collections, which may be handled by the same agency or by separate programs (drinking water is administered by PA DEP, Bureau of Safe Drinking Water, Operator Certification (25 Pa. Code Ch. 302, Subchapter J)). The exact certification structure, exam format, levels, and continuing-education requirements vary by discipline and change over time, so always confirm the current scope and eligibility directly with the certifying agency. Our practice content focuses on the underlying technical material: the same operating principles, math, regulations, and process knowledge that show up on water and wastewater operator exams nationwide.
Frequently asked questions
How does Pennsylvania classify water operators?
Are these the exact questions on the Pennsylvania exam?
Are these practice tests free?
Disclaimer: WaterOperatorPracticeTest.com is an independent study aid. We are not affiliated with PA DEP, Bureau of Safe Drinking Water, Operator Certification (25 Pa. Code Ch. 302, Subchapter J) or any state primacy agency. Always confirm current exam requirements with your state's certification body.