AIH Professional Hydrologist - Groundwater Examination
AIH Professional Hydrologist (PH) Examination - Groundwater
More study resources
Cheat sheet
Keep the key ideas within reach.
ExploreKey terms
Get comfortable with the vocabulary.
ExploreStudy plan
Give each week a clear focus.
ExploreCommon mistakes
Understand the traps and how to avoid them.
ExploreCase studies
Put your knowledge to work in context.
ExploreExam-day guide
Prepare for the day ahead.
ExploreAbout this exam
The Professional Hydrologist (PH) credential is issued by the American Institute of Hydrology (AIH), a non-profit scientific and educational organization founded in 1981 and described by AIH as the only nationwide organization offering certification to qualified hydrologic professionals. AIH positions the PH Exam for experienced professionals ready to demonstrate advanced knowledge and ethical leadership in the field, and states that its exams focus exclusively on knowledge and understanding of hydrology rather than broader or adjacent disciplines. AIH describes certification as a way for the public, employers, and clients to identify water professionals who meet high standards of hydrology knowledge, demonstrate qualified experience, and practice ethically. This independent study page is organized around the three groundwater-relevant areas AIH names for its examinations: fundamentals of hydrology, surface water hydrology, and groundwater hydrology. Preparation should combine a working command of hydrologic fundamentals with quantitative problem practice in groundwater flow, aquifer testing, and well hydraulics, plus review of the ethical standards AIH maintains to protect the public. Because AIH administers the actual examination, candidates should confirm current eligibility, application, and examination-process requirements directly with AIH before scheduling; this page is not affiliated with or endorsed by AIH.
What you'll study
About AIH Professional Hydrologist - Groundwater Examination preparation
Who should sit for the PH Exam rather than the HIT or HT exams?
AIH describes the PH Exam as the route for experienced professionals ready to demonstrate advanced knowledge and ethical leadership in the field. The Hydrologist-in-Training exam is aimed at emerging professionals preparing for a career and future PH or HT certification, and the Hydrologic Technician exam targets those with hands-on field experience. Choose based on where you sit in that progression.
What content areas does the exam cover?
AIH states its exams focus exclusively on knowledge and understanding of hydrology, testing expertise in the fundamentals, surface water, and groundwater. For a groundwater-oriented candidate, that means fundamentals and surface water material is fair game alongside groundwater, so do not study groundwater in isolation.
How long is the exam, how many questions, and what is the passing score?
AIH does not publish these details on the pages reviewed here, so this page does not state them. Confirm the current examination format, item count, time allowance, and passing standard with AIH directly before you build a study schedule around any assumed number.
What does it cost and is there a retake policy?
Fees and retake terms are not stated in the AIH material reviewed for this page, so no figures are given here. AIH notes that from September through December 2026, qualified students and early-career professionals can take the AIH Fundamental Exam at no upfront cost, but that is a time-limited offer for a different exam, not the PH fee.
How should I sequence my study time?
Start with fundamentals, since both of the other areas depend on them: the water balance, unit conversions, Darcy's law, porosity and specific yield, and basic statistics. Then move to groundwater, which is usually the deepest quantitative block, and finish with surface water so you can handle cross-over topics such as stream-aquifer interaction and baseflow.
What are the most common ways candidates lose points?
Unit and dimensional errors dominate: mixing gallons and cubic feet, days and seconds, or transmissivity and hydraulic conductivity. Second is misreading what a question asks, such as a drawdown versus an absolute head. Third is skipping fundamentals because the candidate works in groundwater daily. Write units at every step and sanity-check magnitudes.
How much quantitative problem practice do I need?
Plan on solving problems rather than reading about them. Working through pump-test analysis, flow-net interpretation, mass-balance calculations, and unit conversions by hand builds the speed and error-checking habits that a timed exam rewards. Review any missed problem until you can reproduce the method without notes.
Does AIH certification require continuing education?
AIH maintains a Continuing Education section and lists access to monthly webinars and other continuing education opportunities among the benefits of membership and certification. Verify the specific continuing education obligations that apply to your certification status with AIH, since requirements are administered by the institute.
Is this study page affiliated with AIH?
No. This is independent study material prepared by a third party. AIH is the organization that certifies hydrologists and administers the examinations. For requirements, applications, and the examination process, AIH directs inquiries to its own contact channels, and candidates should rely on those for authoritative answers.