- What CWD Means Here: Certified Well Driller
- Who Issues the Credential and Who Administers the Exams
- The Two-Exam Pathway That Makes the Letters Valid
- The Six General Drilling Domains
- Choosing a Drilling-Method Specialty
- Who Can Apply: Eligibility in Plain Terms
- Fees: What Is Published and What Is Not
- Sample Question Styles With Explanations
- Voluntary NGWA Certification vs. State Licensing
- Keeping the Credential: Annual Renewal
- A Domain-Based Preparation Sequence
- Frequently Asked Questions
- CWD here means Certified Well Driller, a voluntary credential from the National Ground Water Association (NGWA), not any other credential sharing the letters.
- You earn CWD only by passing General Drilling plus at least one drilling-method specialty within 12 months, scoring 70% or higher on each.
- General Drilling alone does not confer the CWD designation; it is one half of the required pair.
- The General Drilling exam has 50 multiple-choice questions in 60 minutes; Construct Water Well carries the most items (16).
What CWD Means Here: Certified Well Driller
On this site, CWD stands for Certified Well Driller. It is a professional designation for people who drill water wells and install pumps, awarded through the National Ground Water Association's voluntary contractor certification program. The letters are shared by several unrelated credentials and terms in other fields, which is why searches for the acronym return a confusing mix of results. If you are here because you work in the water well industry, or because an employer, supervisor, or colleague mentioned the credential, this is the one you are looking at.
The designation signals that a driller has met an experience requirement, supplied professional references, and passed written examinations covering both general drilling practice and at least one specific drilling method. It is not an academic degree, and it is not a government license. That distinction matters enough that it gets its own section below.
If you want other framings of the same question, the site also covers what CWD is, what CWD stands for, and what the certification involves. This article focuses on the meaning of the designation itself and what stands behind the letters.
Who Issues the Credential and Who Administers the Exams
The National Ground Water Association (NGWA) runs the certification program. Examinations are delivered by PSI Services, which administers closed-book, computer-based tests at proctored testing centers. You do not sit the exam at an NGWA office or a job site; you test in a controlled environment with identity checks and supervision.
A few logistics worth knowing before test day:
- A nonprinting, nonprogrammable calculator without an alphabetical keypad is permitted.
- Scratch paper is supplied and collected at the end of your session.
- The exams are closed-book, so you cannot bring reference tables or manuals into the room.
For scheduling windows and deadlines, see the CWD exam dates guide.
The Two-Exam Pathway That Makes the Letters Valid
The most common misunderstanding about this credential is treating General Drilling as the whole exam. It is not. CWD requires General Drilling and at least one drilling-method specialty, both passed within the same 12-month period, with at least 70% on each. Passing General Drilling by itself does not give you the designation.
| Component | What It Covers | Format |
|---|---|---|
| General Drilling | Six formal exam objectives spanning the full job lifecycle | 50 multiple-choice questions, 60 minutes |
| Drilling specialty (at least one) | A specific drilling method | Normally 50 questions; Exam M (Augering and monitoring) has 75 |
| Passing standard | Each exam scored separately | At least 70% on each, within the same 12-month period |
The 70% figure is the required score on each examination. It is not a pass rate, and no current aggregate pass rate has been verified. For a closer look at the score threshold, read the CWD passing score guide, and for what the data does and does not show, see the CWD pass rate discussion.
The Six General Drilling Domains
The General Drilling content outline lists six formal objectives. They follow the natural order of a well project, from arriving at the site to leaving it. Published item allocations are counts of questions, not percentage weights, so the numbers below are the number of items assigned to each area on the 50-question exam.
Domain 1: Mobilize for the Site (10 items)
Everything that happens before the bit touches ground. Expect questions on getting equipment and materials to the location and preparing the site safely.
- Pre-job planning and site readiness
- Safe positioning of the rig and support equipment
- Awareness of utilities and site hazards
Domain 2: Construct Water Well (16 items)
The largest allocation on the exam, and the area where practical drilling knowledge is tested most heavily.
- Drilling and borehole advancement fundamentals
- Casing, screen, and annular materials
- Grouting and sealing practices that protect the aquifer
Domain 3: Rehabilitate Wells (5 items)
Restoring performance to an existing well rather than building a new one.
- Recognizing causes of declining well performance
- Choosing appropriate rehabilitation approaches
Domain 4: Develop Wells (11 items)
Conditioning a newly constructed well so it produces cleanly and efficiently.
- Purpose and methods of well development
- Judging when development is complete
Domain 5: Decommission Wells (3 items)
Properly closing a well that is no longer in service, a small slice of the exam that still demands precision.
- Why abandoned wells must be sealed correctly
- General sequence for permanent closure
Domain 6: Demobilize the Site (5 items)
Wrapping up the job responsibly.
- Cleanup and restoration of the work area
- Final equipment removal and site documentation
These six headings are the formal General Drilling objectives. They are not a complete blueprint for the specialty exam you must also pass. For a deeper breakdown, the CWD exam domains guide walks through each content area.
Key Takeaway
Construct Water Well (16 items) and Develop Wells (11 items) together account for 27 of the 50 General Drilling questions. Those two domains deserve the largest share of your study hours, though no area should be skipped.
Choosing a Drilling-Method Specialty
Because the specialty exam is mandatory, picking one is a real decision. The specialty exams are organized around drilling methods, and they normally contain 50 questions each. The notable exception is Exam M, Augering and monitoring, which has 75 questions, so budget extra stamina and time awareness if that is your choice.
A sensible way to choose:
- Start with your daily work. The method you run most often is the one where your experience will carry you.
- Consider the regional market. Geology and local practice shape which methods are common in your area.
- Check the specialty outline separately. Do not assume the General Drilling study materials cover it. The supplemental study guide maps its references to the six General Drilling headings and does not supply complete specialty coverage.
- Plan the 12-month window. Both exams must be passed within the same 12-month period, so avoid starting with a specialty you cannot realistically prepare for in that time.
Who Can Apply: Eligibility in Plain Terms
Sitting the exam is only part of earning the designation. NGWA sets prerequisites that you must satisfy:
- You must be age 20 or older.
- You need 24 consecutive months of full-time drilling or pump-installation experience.
- You must provide two written professional references from people not affiliated with your current employer.
- You must sign the required agreement and submit a current-year affidavit.
- Application materials must arrive within 12 months of the qualifying examination session.
The full walkthrough is in the CWD requirements guide.
Fees: What Is Published and What Is Not
The published examination fee is $75 per examination, the same for members and nonmembers. Because the pathway requires two exams, a first-attempt candidate pays at least $150 in examination fees. That is a floor, not a complete budget.
Several costs sit outside that number:
- The candidate bulletin warns of an additional certification-application fee for nonmembers but does not state the amount, so confirm it directly with NGWA.
- Study materials, travel to a testing center, time away from work, and any retakes are not included.
- Annual renewal carries its own fees, covered below.
For a structured view of the full financial picture, see the CWD certification cost breakdown, and for whether the spend pays off, the ROI analysis.
Sample Question Styles With Explanations
The exam uses multiple-choice items. The examples below are original practice questions written to show the style and reasoning, organized by domain. They are illustrations, not actual exam content.
Practice Question: Domain 2, Construct Water Well
A driller is placing the annular seal around a well casing. What is the primary purpose of this seal?
- A. To increase the diameter of the borehole
- B. To prevent surface contamination and cross-flow between zones from traveling along the casing
- C. To make the casing easier to remove later
- D. To reduce the cost of casing material
Answer: B. The annular seal blocks pathways along the outside of the casing. Without it, surface water or water from other zones could migrate down or across and compromise the well and the aquifer.
Practice Question: Domain 4, Develop Wells
Why is a newly constructed well developed before it is placed into service?
- A. To remove fine material near the screen and improve water flow into the well
- B. To lower the total depth of the well
- C. To replace the need for grouting
- D. To satisfy marketing requirements only
Answer: A. Development clears drilling debris and fines from the area around the screen so the well yields water efficiently and produces less sediment.
Practice Question: Domain 5, Decommission Wells
What is the main reason an unused well must be properly decommissioned rather than simply abandoned?
- A. Open wells are valuable as storage space
- B. It guarantees the pump can be reused
- C. An open or poorly sealed well can serve as a direct route for contaminants to reach groundwater
- D. It removes the need for any future permits
Answer: C. A neglected well is a conduit. Proper sealing restores protection of the aquifer and eliminates a physical hazard.
For more practice in this style across all six categories, use the CWD practice test. A condensed review lives in the CWD cheat sheet.
Voluntary NGWA Certification vs. State Licensing
This is the point most newcomers get wrong. NGWA certification is voluntary. State licensing, where it exists, is a legal requirement set by the state and administered separately.
| Feature | NGWA Certified Well Driller | State Licensing |
|---|---|---|
| Nature | Voluntary professional credential | Legal authorization to work, where required |
| Issued by | National Ground Water Association | State or regional authority |
| Basis | Experience, references, and two passed exams | Varies by jurisdiction |
| Replaces the other? | No | No |
Holding CWD does not substitute for a state license where one is required, and a state license does not automatically earn you the CWD designation. Renewal of the NGWA credential even lists compliance with licensing requirements as a condition. Always verify the rules in the state where you work. For the employment angle, see CWD jobs and the CWD salary guide.
Keeping the Credential: Annual Renewal
The designation is not permanent. Renewal is annual and involves:
- Seven continuing education points (CEPs)
- An affidavit
- Applicable fees
- Compliance with licensing requirements
The stated renewal due date is December 31. The currently linked 2027 renewal form lists $50 for members and $150 for nonmembers; these are renewal fees and should not be confused with the $75 per-exam fee.
A Domain-Based Preparation Sequence
Rather than generic scheduling, tie your preparation to the structure of the exam. This sequence assumes you are also preparing a specialty and gives the heaviest General Drilling domains the most time. The supplemental NGWA-authored General Drilling study guide maps its preparation references to the same six headings, which makes it a natural companion to this plan.
Construct Water Well
- Largest allocation at 16 items, so start here
- Focus on casing, screen, and sealing logic
Develop Wells and Mobilize for the Site
- Development (11 items) and mobilization (10 items) together form a large block
Rehabilitate, Decommission, Demobilize
- Smaller allocations (5, 3, and 5 items) that are quick to cover but easy to underestimate
Specialty exam and mixed review
- Study your chosen method from its own outline
- Take timed practice sets against the 60-minute General Drilling limit
For a fuller plan, read the CWD study guide, the CWD training overview, and the difficulty guide. When you are ready to test yourself, start a session on the main practice test.
Frequently Asked Questions
CWD means Certified Well Driller, a voluntary professional credential from the National Ground Water Association for people who drill water wells and install pumps. It is earned by meeting experience and reference requirements and passing two examinations.
No. General Drilling is only one required exam. You must also pass at least one drilling-method specialty exam, both within the same 12-month period, scoring at least 70% on each.
The General Drilling exam has 50 multiple-choice questions to be completed in 60 minutes. Specialty exams normally have 50 questions, while Exam M, Augering and monitoring, has 75.
No. NGWA certification is voluntary and issued by a professional association, while state licensing is a legal requirement where it applies. One does not replace the other, so check the rules where you work.
Renewal is annual and requires seven continuing education points, an affidavit, applicable fees, and licensing compliance. The stated due date is December 31, but sources conflict on late fees, so confirm the deadline with NGWA.