Visible and Invisible Waters at the Hungarian Academy of Sciences: Live Demonstration on Groundwater and the NaBa-MAR® Innovation

On 12 December 2025, a live demonstration connected to the hydrogeological exhibition “Visible and Invisible Waters Tabletop Model & Nature-Based Managed Aquifer Recharge Model” took place at the Headquarters of the Hungarian Academy of Sciences (MTA), Budapest, attracting strong interest from a broad audience. The event was organised as part of the MTA200 Earth Sciences event series.

The programme was delivered through the joint contribution of Dunakanyar Cultural Landscape and Environmental Protection Association (DUNAKÉKE) (Mónika Korcsák, Gábor Korcsák), the József and Erzsébet Tóth Endowed Hydrogeology Chair, Eötvös Loránd University (ELTE) (Judit Mádl-Szőnyi, Márk Szijártó, Ildikó Erhardt, Imola Koszta, Hanna Lukács), and ELTE’s Kármán Laboratory (Miklós Vincze).

Throughout the day, school groups, adult visitors, senior participants and water professionals visited the exhibition space on the mezzanine level, where two thematic stations guided them through the “seen” and “unseen” parts of the water cycle—and how nature-based solutions can help societies adapt to climate extremes.

Station 1: “Visible and Invisible Waters” — Making Human Impacts Understandable

The tabletop model follows water from clouds and precipitation through landscapes to a river valley, demonstrating the close coupling of surface water and groundwater. Visitors could observe how water infiltrates through soils to the water table, then continues its journey—largely invisible to us—within complex groundwater flow systems, moving from higher recharge areas toward lower-lying discharge zones.

A core message of the demonstration was to make human interventions and their consequences tangible. The model highlights, in clearly separated elements:

• Pollution sources (e.g., mining activities, oil drums),

• Groundwater abstractions that can contribute to declining groundwater levels, and

• “Good practices” that support local water retention, infiltration and improved landscape water balance.

Among the nature-friendly, positive examples presented were:

• Agricultural cover and mulching, which protect soils from drying and support infiltration,

• An infiltration pond, illustrating how surface water can be retained locally and gradually routed underground, and

• A brushwood hedge, functioning as a biodiverse green strip that supports water retention and soil protection while providing habitat.

Station 2: NaBa-MAR® Board Model — Nature-Based, Targeted Managed Aquifer Recharge

The second station focused on the NaBa-MAR® physical model, demonstrating the principles of Nature-Based Managed Aquifer Recharge in a managed, controlled way that still builds on natural processes. With the model, visitors could trace how available surface water—for example precipitation or temporary surplus water in streams—can be guided into aquifer layers through carefully designed, site-specific interventions.

During the live explanation, we walked participants step-by-step through:

• how the model is constructed,

• how groundwater flow develops within it,

• what happens when additional water is infiltrated into the system, and

• why rapid drainage via channels should often be avoided if the goal is to retain water in the landscape, in soils, and in groundwater storage.

A key takeaway was that the subsurface can behave as a natural reservoir: infiltrated water can increase groundwater storage while contributing to a more stable local water balance—a crucial aspect of climate adaptation.

Relevance to ClimEx-PE: From Demonstration to Climate-Resilience Solutions

The event directly reflects the mission of ClimEx-PE, which investigates how groundwater flow systems can buffer climate extremes and how nature-based managed aquifer recharge approaches can be designed, evaluated and scaled as part of climate adaptation and sustainable water management.

By translating hydrogeological processes into a hands-on experience, the two models supported several ClimEx-PE priorities:

• Knowledge transfer and literacy: making groundwater processes understandable for non-experts, while enabling deeper technical discussion with professionals.

• Nature-based solutions in practice: demonstrating how NaBa-MAR® can help retain water locally and support aquifer recharge in a way that aligns with ecosystem functions.

• Adaptation to extremes: illustrating, in an intuitive way, how increased infiltration and subsurface storage can help mitigate drought impacts, reduce risks associated with hydrological extremes, and support long-term resilience.

Experience-Based Learning for All Ages

The audience composition confirmed the value of interactive, experience-based outreach. Younger visitors often highlighted “the journey of a water drop” and the most visual parts of the tabletop, while participants with professional backgrounds initiated discussions about hydrogeological mechanisms, implementation constraints, and practical applicability.

Feedback repeatedly underlined that making “invisible” processes tangible had the strongest impact: many visitors reported that they could finally see how closely surface water and groundwater are connected, and why responsible, long-term groundwater stewardship is essential for sustainable development and climate resilience.

ClimEx-PE will continue to build on such outreach formats to strengthen societal understanding of groundwater—and to support informed dialogue on nature-based adaptation options, including NaBa-MAR®, across stakeholder groups.