Here’s a look back at the IAHS 2025 Scientific Assembly in Roorkee!

Between 5 and 10 October 2025, the XII^th Scientific Assembly of the IAHS brought more than 600 hydrologists together in Roorkee, India – a university town nestled between the River Ganges and the foothills of the Himalayas.

Hosted on the beautiful campus of the Indian Institute of Technology (IIT) Roorkee, the week was filled with lively discussion, new ideas, and lasting connections. Hydrologists from around the world gathered to share research, exchange experiences, and celebrate our shared mission of advancing hydrological science.

One of the stand-out features of IAHS2025 was its fresh new conference format, designed to foster collaboration and encourage more open discussion across disciplines and generations.

The programme was rich and varied, from inspiring scientific sessions to memorable community moments:

The SYSTA awardees were celebrated at a special luncheon on Monday, recognising the energy and ideas of the next generation of hydrologists.

The HSJ Retreat and dinner on Monday evening featured the Hydrological Sciences Journal Associate Editor Award for 2024. Marina Batalini de Macedo was awarded the prestigious Hydrological Sciences Journal Associate Editor Award at a dinner in India last night. The award is granted for outstanding overall contribution to the Journal’s impact and visibility, and excellence in supporting authors and editors through the peer review process. The award is granted annually by IAHS - International Association of Hydrological Sciences, with the support of Taylor & Francis Group, to one Associate Editor identified by the HSJ Editors.

The IAHS Awards evening on Wednesday featured the International Hydrology Prize which is awarded annually by IAHS, with UNESCO and WMO, to two people who have made an outstanding contribution to hydrological science. The award winners for 2025 are:

   Dooge medal - John W. Pomeroy (Canada)
   Volker medal - Giuliano Di Baldassarre (Sweden).

The IAHS Tison Award, established in 1982, aims to promote excellence in research by young hydrologists. The Award is granted for an outstanding paper published by IAHS in a period of two years previous to the deadline for nominations. The award winners for 2025 are:
RuiRui Xu, Dexun Qiu and ChangXue Wu (China) for the paper: Xu, R., Qiu, D., Wu, C., Mu, X., Zhao, G., Sun, W., & Gao, P. (2023). Quantifying climate and anthropogenic impacts on runoff using the SWAT model, a Budyko-based approach and empirical methods. Hydrological Sciences Journal, 68(10), 1358–1371. Https://doi.org/10.1080/02626667.2023.2218551. 
And the award winner for 2024 is:
Martin Addi (Ghana) for his work on the 2022 Hydrological Sciences Journal paper: Evaluation of imputation techniques for infilling missing daily rainfall records on river basins in Ghana, Hydrological Sciences Journal, Volume 67, Issue 4, Pages 613-627, DOI: 10.1080/02626667.2022.2030868.

The Falkenmark Award for best PhD thesis recognises outstanding contributions to hydrological understanding of water scarcity and water supply in one or more financially disadvantaged countries. The award winner for 2025 is Vinícius Bogo Portal Chagas (Brazil) for his PhD thesis entitled "Hydrological extremes in Brazil: Large-scale patterns, mechanisms, and change". He has provided significant contributions to the understanding of large-scale patterns, mechanisms, and climate change impacts on water availability and coupled hydrological extremes in South America.

The Stockholm Water Prize Lecture Series – a highlight of the week – saw laureates deliver thought-provoking talks that reminded us all of the global importance of hydrology. For the first time, IAHS has introduced a dedicated session to celebrate the Stockholm Water Prize — the world’s most prestigious distinction in the field of water — and will continue this initiative in future IAHS General Assemblies. By doing so, we aim to recognise and amplify the Prize’s unique role in highlighting scientific excellence and inspiring progress in water science. Over the past three decades, Stockholm Water Prize Laureates have represented a wide range of professions, disciplines, and regions — united by their outstanding achievements in advancing sustainable water solutions for people and the planet. In the special session organised during the IAHS Scientific Assembly in Roorkee, IAHS President Professor Salvatore Grimaldi and the LOC Chair Professor Sumit Sen chaired the discussion, which featured interventions from:
   2025 Laureate – Professor Gunter Bloschl (Austria),
   2024 Laureate – Professor Taikan OKI (Japan),
   2023 Laureate – Professor Andrea Rinaldo (Italy). 
This unprecedented event was deeply inspiring for all participants — particularly for young scientists — reflecting the transformative power of hydrological science in bridging theory, innovation, and real-world impact to ensure a more resilient and sustainable water future.

Community and culture were at the heart of the week, with events such as the sports and yoga evening, the festive IAHS Gala Dinner, and a Cultural Showcase on Thursday – all filled with laughter, conversation, and camaraderie.

As part of the Scientific Assembly, IIT Roorkee hosted a vibrant Cultural Evening on 9 October. This special event mesmerized participants with rich traditions, music, and dance forms of India, and offered a unique glimpse into the country’s cultural diversity. The evening featured a professional troupe of dancers, singers, and musicians who presented a carefully curated program. Highlights included:
   Nanda Raj Jaat – a traditional offering from Uttarakhand,
   Kumaoni Dance (Chhapeli) – celebrating Himalayan culture,
   Rajasthani Kalbeliya Dance – the world-renowned desert folk dance,
   Chhattisgarhi Folk Dance (Karma) – symbolizing community spirit and tradition,
   Punjabi Bhangra – a vibrant finale of rhythm and energy.

The cultural showcase not only provided entertainment but also connected participants with India’s artistic heritage, making the Assembly experience more memorable and immersive.

A special outing took participants to Haridwar, the sacred city where the Ganges River emerges from the Himalayan foothills. Here, attendees experienced the unique blend of spirituality, culture, and landscape that connects deeply with the essence of hydrology.

Quote from a delegate, “IAHS2025 reminded us that when we come together – across continents and disciplines – we strengthen not only the science, but the spirit of our community.”

As the Assembly concluded, the sense of connection and shared purpose was stronger than ever. The success of IAHS2025 reflects not only the hard work of the organisers and volunteers, but also the enthusiasm and generosity of the entire IAHS community. Explore more highlights:
   [Link to photo gallery]
   [Link to IAHS LinkedIn]
   [Link to HSJ LinkedIn]
   [Link to IAHS YouTube]

Looking ahead, we are already excited to gather again – this time at the General Assembly of the International Union of Geodesy and Geophysics (IUGG) in Incheon, South Korea, in July 2027. Until then, let’s keep the momentum going and continue building the future of hydrological science together.

Quote from the IAHS President, Prof. Salvatore Grimaldi “The Scientific Assembly in Roorkee was more than a conference — it was a celebration of global collaboration and shared passion for hydrology. My sincere thanks to everyone who joined us, whether in person or in spirit, for making IAHS2025 such a success.”

Our deepest and most sincere thanks must go to the Local Organising Committee chaired by Prof. Sumit Sen (Head, Department of Hydrology, IITR) convened by Professors D.S. Arya (Deptartment of Hydrology, IITR) and Ankit Agarwal (Deptartment of Hydrology, IITR), their Organising Secretaries, Treasurers, Members and Nominated SPOCs. Not to mention the many kind and expert volunteers without whom this event would not have been a success.

Until then, let’s carry forward the inspiration, connections, and momentum of IAHS2025 as we continue advancing hydrological science together.