CWD Passing Score 2026: Exactly What You Need to Pass

The 70% Rule: What the Passing Score Actually Is

The passing standard for the National Ground Water Association's Certified Well Driller credential is simple to state: you must earn at least 70% on each examination you sit. There is no curve published in the candidate materials, no blended average that lets a strong result in one exam rescue a weak result in another, and no partial credit for coming close. Each exam stands on its own.

That per-exam structure is the single most important thing to understand about the CWD passing score. Many candidates prepare as though they are chasing one number. In reality you are chasing the same threshold twice, on two different bodies of knowledge, inside a fixed window of time.

Why One Passing Score Is Not Enough

Here is where the certification differs from many single-exam credentials. Certified Well Driller is earned by passing General Drilling and at least one drilling-method specialty, and both must be passed within the same 12-month period, each at 70% or better. Passing General Drilling alone does not confer CWD. It is a necessary half of the pathway, not the whole credential.

That has practical consequences for how you think about your score:

• A pass on General Drilling is not a finished credential. You still owe a qualifying specialty result.
• A failed specialty does not erase General Drilling, but the 12-month clock matters, so plan your retake timing carefully rather than assuming you can circle back whenever convenient.
• Each exam is scored independently. A 90% on General Drilling does not offset a 65% on your specialty.

If you are still mapping out whether you qualify to sit at all, review the full CWD eligibility and prerequisites guide before you invest in prep.

Question Counts and Time: What 70% Means in Items

Exams are closed-book and computer-based, administered by PSI Services at proctored centers. The General Drilling exam is 50 multiple-choice questions in 60 minutes. Drilling specialty exams normally have 50 questions as well, with one notable exception: Exam M, Augering and monitoring, has 75 questions.

Translating 70% into raw item counts is a useful mental exercise, though you should treat the arithmetic as a planning aid rather than a guarantee of how any individual form is scored:

Notice what that means for margin. On a 50-question exam you can miss at most 15 items. That sounds generous until you realize that a few weak topic areas can easily consume that cushion. With 60 minutes for 50 questions on General Drilling, you have a little over a minute per item, so there is time to think but not time to dwell.

Where the General Drilling Points Come From

The General Drilling exam is organized into six content areas. The published allocations are item counts, not percentage weights, so avoid converting them into percentages in your head and treating the result as official. Here is how the 50 items are distributed:

Two things jump out. First, Construct Water Well is the heavyweight at 16 of 50 items, the single largest allocation. Second, Develop Wells at 11 items and Mobilize for the Site at 10 items together with Construct account for the bulk of the exam. Those three areas alone supply 37 of the 50 items.

An important caveat: these six lines are the formal General Drilling exam objectives. They are not a complete blueprint for the additional specialty you must also pass. Your specialty preparation needs its own source material. For a deeper walk through each content area, see our complete guide to all six CWD content areas.

Choosing a Drilling Specialty Before You Sit

Because the CWD passing score applies to your specialty as well, the specialty you choose directly affects your odds. Pick the method that matches your actual field experience. A candidate who has spent two years running a particular rig type will usually find that specialty's questions intuitive, while a method you have only read about will feel abstract and trap-laden.

• Match experience to method. Your 24 months of qualifying full-time drilling or pump-installation experience should inform which specialty feels natural.
• Note the length difference. Exam M, Augering and monitoring, is 75 questions versus 50 for the typical specialty, which changes both pacing and the number of correct answers you need.
• Source your own study material. General Drilling has a mapped study guide, but the specialty does not share it, so budget extra effort to find specialty-specific references.

Passing Score Is Not a Pass Rate

It is worth separating three ideas that are often blurred together in forum posts and low-quality summaries:

• Passing score: the 70% you must earn on each exam.
• Pass rate: the share of candidates who succeed. No current aggregate CWD figure has been verified.
• Difficulty: a subjective measure shaped by your experience, your specialty, and your preparation.

If you want to calibrate how demanding the exams feel in practice, our guide on how hard the CWD exam is covers difficulty without inventing numbers. And for the cost side of retaking, the published fee is $75 per examination for members and nonmembers, so two first-attempt exams run at least $150. That is not an all-inclusive certification budget; the candidate bulletin separately warns of an additional certification-application fee for nonmembers without stating the amount. See the full CWD certification cost breakdown for how to plan around the unknowns.

Practice Questions That Mirror the Domains

The questions below are original, written to illustrate the style of reasoning each domain rewards. They are not drawn from any live exam. Try each before reading the explanation.

For more of this style of drill, take a full set on our CWD practice test platform, which maps questions to the same six content areas.

Test-Day Mechanics at the PSI Center

Knowing the rules of the room protects your score from avoidable stress. The exams are closed-book and computer-based at proctored PSI centers. A nonprinting, nonprogrammable calculator without an alphabetical keypad is permitted. Scratch paper is supplied and is collected at the end, so do not plan to carry notes out.

• Bring the right calculator. A programmable or alphabetical-keypad model is not allowed, so test your device against the stated rule well before exam day.
• Use scratch paper strategically. Jot unit conversions or formulas you want to recall early, since you cannot keep the sheet afterward.
• Watch the clock. On General Drilling, 60 minutes for 50 questions leaves little slack for lingering.

For scheduling windows and registration deadlines, use our CWD exam dates and scheduling guide, and remember that application materials must arrive within 12 months of the qualifying examination session.

A Domain-Weighted Prep Timeline

Rather than a generic schedule, tie your calendar to where the points live. Because Construct Water Well, Develop Wells, and Mobilize for the Site hold 37 of 50 General Drilling items, they get the earliest and longest blocks. Build in a separate stretch for your specialty, since it is scored independently.

For a broader plan built around first-attempt success, pair this with our CWD study guide.

After the Score: Application, Renewal, and State Licensing

Clearing 70% on both required exams is a milestone, not the finish line. Eligibility requires being age 20 or older, having 24 consecutive months of full-time drilling or pump-installation experience, supplying two written professional references unaffiliated with your current employer, the required agreement, and a current-year affidavit.

Certification then requires annual upkeep. Renewal is yearly and involves seven continuing education points (CEPs), an affidavit, applicable fees, and compliance with licensing requirements, with a stated due date of December 31. The currently linked 2027 renewal form lists $50 for members and $150 for nonmembers; these are renewal fees, not examination fees.

Also keep in mind that this is a voluntary NGWA credential, distinct from state licensing. Passing your exams does not replace whatever license your state requires to drill, and renewal explicitly requires compliance with licensing requirements. If you are weighing the payoff of the credential against these ongoing obligations, see whether the CWD certification is worth it and our CWD salary guide.

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