IAH’s 53 national chapters are voluntary groups that operate within their own national regulatory frameworks while upholding IAH’s principles and aims. Each chapter develops its own identity and activities—often with unique logos—and focuses on locally relevant talks, webinars, seminars, workshops, and professional engagement. Their contributions significantly strengthen the global hydrogeology community. Highlights from 2025 illustrate the breadth and impact of their work.
The Spanish National Chapter delivered several major initiatives, including a well‑attended Well Construction and Sealing Course in Alicante, supported by local government and the University of Alicante. The course attracted 75 in‑person participants and 70 online attendees from fields such as hydrogeology, agronomy, and forestry engineering. The Chapter also contributed to drafting groundwater regulations in Honduras, supported the Colombian Hydrogeology Congress, signed a collaboration agreement with CONAMA—Spain’s leading environmental forum—and funded the Best Scientific Poster Award at the 28th Salt Water Intrusion Meeting.
The Turkish National Chapter held its biennial symposium in Isparta, covering a wide range of topics including climate change impacts, karst hydrogeology, coastal aquifers, isotope hydrology, groundwater monitoring, hydrogeothermal systems, and modelling.
In Slovakia, the Slovak National Chapter and the Slovak Association of Hydrogeologists organised their 7th field hydrogeological seminar on groundwater interactions with anthropogenic activities, particularly in relation to highway tunnel construction. The event brought together experts from water management, environmental protection, consulting, balneology, academia, and research institutions.
The Argentine National Chapter continued publishing the Revista Argentina de Hidrogeología, an open‑access journal that fills a regional gap for Spanish‑language hydrogeology publications. The Chapter collaborates widely across Latin America and relies on the voluntary work of its editorial team.
The Hungary National Chapter focused on preparations for the 2026 IAH World Groundwater Congress in Budapest, launching the official congress website in 2025.
The Chilean National Chapter hosted a national congress featuring 41 oral presentations, 30 posters, and keynote lectures by leading hydrogeologists from Brazil, Mexico, and Chile. The event brought together professionals, academics, and students to discuss advances in groundwater management and protection.
The Great Britain National Chapter and the UK Hydrogeological Group held their annual meeting on the theme Sustainable Groundwater: Old and New. The programme included the Ineson Lecture by Dr Bridget Scanlon on conjunctive water management and the Darcy Lecture by Dr Grant Ferguson on fossil groundwater systems and their strategic value.
Finally, colleagues in Switzerland published a national survey examining groundwater in the context of global megatrends – climate change, land‑use change, population growth, and digitisation – while exploring differences in perspectives across research, implementation, water supply, and consulting sectors.
Together, these activities demonstrate the vitality, diversity, and professional value of IAH’s national chapters worldwide.