Groundwater

Madagascar is becoming increasingly vulnerable to the impacts of climate change and related disasters, namely drought, cyclones and flooding. While it is well-recognised that southern Madagascar has been suffering from drought for decades, it has not yet been properly acknowledged that northern Madagascar (The Diana region, Antsiranana and surrounding villages (e.g. Namakia)). Andranovondronina is also beginning to feel the impacts of drought. This is particularly affecting small-holder farmers who rely on rain-fed agriculture for both food and income. The climate of northern Madagascar is typically categorised as "transition tropical", so the onset of drought could also have major implications for the rest of the island. Northern Madagascar used to have a 6-month dry season and a 6-month rainy season, but the length of the rainy season has reduced significantly in recent years and is now locally considered a "cyclone season". More people are relying on groundwater, which is often contaminated with bacteria and excrement, leading to an increase in water-borne diseases and illnesses.

Decline in groundwater quality is the challenge I have observed and experience in my country. Groundwater systems are particularly important in places where no rivers flows on the surface. In Yucatan, Mexico, for example, there are no rivers on the surface but we can find the Yucatán Peninsula Aquifer one of the biggest aquifers in the world. Today, the peninsula only has a population of 2 million, yet groundwater is being overexploited and polluted. In the peninsula, all socio-economic sectors rely directly or indirectly on groundwater. The main users – agriculture and industry – are causing high levels of pollution and severely overexploiting the cenotes. The quality of groundwater is also being affected by the construction of roads, buildings and other modifications that include pumping wells, infrastructure for tourism and the use of technology to extract and modify groundwater. In addition, warmer temperatures and increasingly unpredictable rainfall during the year are making it harder to store water. Another factor is that the large number of cenotes and lack of reliable hydrological data are making it difficult for users to monitor and control their usage of groundwater. Consequently, the population faces a greater risk to its groundwater reserves than is currently recognized. I would like use time–space evidence from the natural and social sciences for Earth information systems, but to find approaches to better integrate Indigenous knowledge and in situ observations from local communities that can be used to identify/estimate parameters that can support the management of aquifers.Y

Jordan’s water scarcity is primarily driven by overextraction of groundwater resources, inadequate rainfall, and inefficient water management practices. The country’s renewable water resources are estimated at less than 100 cubic meters per capita annually, far below the water poverty threshold of 500 cubic meters per capita. The overuse of aquifers, such as the Disi and Azraq aquifers, has led to water quality degradation and declining availability (Al-Zu’bi, 2007). The issue is exacerbated by climate change, which has resulted in erratic rainfall patterns, increased temperatures, and prolonged droughts (Al-Karablieh et al., 2016). Additionally, the rapid population increase, including the influx of refugees, has intensified demand for water resources. Agricultural activities, which consume approximately 50% of the country’s water supply, often rely on inefficient irrigation methods that contribute to groundwater depletion. If left unaddressed, the crisis will continue to threaten Jordan’s water security, agriculture, and public health.

Water availability is a critical issue for smallholder farmers in Southwest Kyrgyzstan, where natural springs serve as the primary water source for irrigation, livestock, and household use. However, these springs are becoming increasingly unreliable due to climate change, land degradation, and inefficient management practices. Water-related challenges include: Seasonal and interannual fluctuations in spring discharge, leading to water shortages during dry periods. Climate change impacts, such as rising temperatures and altered precipitation patterns, reducing groundwater recharge. Water loss due to inefficient infrastructure, including seepage and evaporation from open channels. Lack of monitoring and sustainable management strategies, leading to overuse and depletion of spring water resources. These challenges directly impact agricultural productivity, food security, and rural livelihoods, making it essential to develop adaptive water management strategies to optimize spring water use and ensure long-term sustainability. This research focuses on hydrological assessments, water conservation techniques, and community-based management approaches to improve water security for smallholder farmers in the region.

Groundwater is a critical resource for drinking water, agriculture, and industry. With increasing anthropogenic activities and exponentially increasing population, groundwater in India is facing several challenges, related to quality as well as quantity, due to over-extraction, pollution, and climate change. Over-exploitation of groundwater may impact the availability and quality of groundwater which is not sustainable. Moreover, due to pollution in surface water, groundwater quality is also affected. In most of the cities of India, the quality of groundwater is below standard. Remote sensing and artificial intelligence can play a very vital role in monitoring the quantity as well as quality of groundwater. As, it is clear that presently no remote sensors can directly be used for groundwater observations, but by using surface features anomalies and gravity data obtained by various satellites, optimal groundwater management can be done using remote sensing. Space4water is one of the best communities addressing water related issues and work towards sustainable solutions. For the last three years, I am following this community, and I find that the community consists of scientists, NGO, policy makers etc. This combination has the potential to resolve issues related to any challenges related to social issues. I am looking for few global research partners who work for groundwater management using space technology. I am equally looking for data driven resource persons who can collaborate with me on real field conditions of various countries, related to groundwater management. What has been done so far is listed below: • Worked on GRACE satellite data and used it in field condition to study groundwater anomalies of few cities of India. • Developed spatio-temporal maps of Standardized Groundwater Index (SGI). • Worked on water quality of water bodies. • Used various satellite data to map water spread areas of various water bodies. • Worked on machine learning models to study in situ remediation of contaminated groundwater.

Water scarcity episodes followed by flooding events demands human intelligence and technological intervention for proper administration, to protect lives and valuable resources needed to sustain life.

There are times when the high demand for water in West Africa, particularly in the Sahel region, surpasses the supply, or when poor quality makes it difficult to use. Freshwater resources suffer from a decline in quantity due to water stress (dry rivers, over-exploitation of aquifers, etc.). Because of this scarcity, disputes between consumers of water are common. Uncontrolled urban growth makes poor sanitation worse since treated wastewater is thrown into rivers, lakes, and the ocean.

Egypt faces significant water scarcity due to its arid climate, rapid population growth, and dependency on the Nile River. Limited rainfall and inefficient water management exacerbate the crisis. Space technology can play a crucial role in monitoring water resources, optimizing agricultural water use, and identifying potential groundwater sources.

The Kingdom of Bahrain has an arid to semi-arid climate with minimal rainfall amount per year. The rapid increase in urbanization and population growth has placed a huge demand on water resources. The only natural resources available in the country and what has been relied on historically for water usage are spring waters and ground water, which are quickly being depleted due to the increasing demands on water needs. Due to the limits of groundwater and spring waters, they are now majorly complemented with non-conventional water resources to supply the country’s needs. The country has invested heavily in water desalination plants of sea water to meet domestic needs and tertiary sewage treatment plants for municipal and agricultural uses through water and treated wastewater networks.

In Nepal’s Middle Hills, community-managed forests have successfully reversed deforestation, but they are now unintentionally contributing to water insecurity. Afforestation has heavily favored Pinus roxburghii, a fast-growing conifer with high year-round evapotranspiration and low infiltration capacity, significantly reducing groundwater recharge. As pine offers limited economic value, forest users increasingly shift to Sal (Shorea robusta) forests, valued for timber and compostable leaf litter. This shift concentrates human activity—such as litter collection, grazing, and trampling—around Sal patches, causing surface compaction and further reducing infiltration. Combined with unplanned road construction that disrupts natural flow paths, these disturbances have degraded upland recharge zones. Once crucial for replenishing groundwater, these uplands are now losing their recharge capacity, leading to measurable declines in groundwater storage and drying of springs in foothill and riparian zones that once flowed year-round. The consequences are widespread and socio-ecologically severe. Rural and Indigenous communities relying on spring-fed systems for drinking water, irrigation, and livestock now face escalating dry-season scarcity. Women and elderly members of marginalized groups bear the greatest burden, while increasing outmigration to urban centers exacerbates inequality. Yet forest governance remains focused on canopy cover and carbon sequestration, often overlooking essential hydrological processes like infiltration, baseflow, and subsurface storage. The continued decline in groundwater recharge also raises long-term concerns about shallow aquifer sustainability and overall water security. This situation is further complicated by a lack of reliable, long-term ground-based hydrometeorological data—many precipitation, temperature, and stream discharge records are missing or incomplete due to sensor failure—making it difficult to calibrate ecohydrological models and to design informed forest and water policies. Fortunately, space-based technologies provide a powerful solution. Remote sensing allows for long-term monitoring of vegetation, precipitation, soil moisture, and terrain, revealing the drivers of spring decline. When paired with ecohydrological modeling and community knowledge, these tools can guide forest management strategies that restore groundwater recharge and help achieve SDG targets 6, 13, and 15. Goals and milestones: The main goal of this research is to assess and mitigate ecohydrological trade-offs in Nepal’s Middle Hills caused by unscientific forest expansion under community forestry (CF). While CF has successfully increased forest cover, it has often overlooked hydrological impacts—particularly where high water-use species like pine have been planted without considering water balance consequences. This has led to declining baseflows, reduced groundwater recharge, and increased dry-season water stress. A key focus is to bridge the gap between Indigenous forest management practices and scientific understanding of forest-water interactions. By integrating Regional Hydro-Ecological Simulation System (RHESSys), ecohydrological modeling, satellite remote sensing, and community-level knowledge, the project aims to reveal how forest type, topography, and land use influence spring recharge zones, groundwater dynamics, and soil moisture retention. Research has shown that nearly 70 per cent of the springs in the region are degrading, threatening long-term water security. One of the critical goals of this research is to identify vulnerable and resilient spring zones—and ultimately support the rebirth of these springs through improved forest and land-use strategies. Short-term milestones include generating high-resolution maps of vegetation phenology, evapotranspiration, and groundwater storage (1985–2025), and validating RHESSys outputs with both field data and satellite products. In the mid-term, the study will identify groundwater-rich zones for future water-resilient settlements, simulate climate scenarios, and collaborate with local stakeholders. The long-term objective is to promote scientifically informed, community-adapted forest governance that enhances both ecological and water resilience across Nepal’s Middle Hills.

The Congo Basin (CB), home to the world’s second-largest river basin and tropical rainforest (Laraque et al., 2020), holds significant groundwater resources (Kasongo-Numbi, 2008; MacDonald et al., 2012; Tourian et al., 2023). Despite the abundance of surface water within the region, groundwater is a crucial source of freshwater for the vast majority of the CB’s population. It plays a vital role in sustaining human consumption, particularly for the rural population, also, for ecosystems and agriculture even though the latter is still rainfed. Domestic water use constitutes the first sector that withdraw the large amount of groundwater in the basin. The water withdrawal is projected to grow significantly due to the human population that is expected to double by 2050 in Africa (Partow, 2011, United Nations, 2019). Additionally, considering the emerging importance of the global change due to climate change and environmental alterations that have already affected surface water within the basin (Reed and Miranda, 2007; Wongchuig et al., 2023), groundwater is likely to become a critical resource for future development in the region. Therefore, there is an urgent need for a sustainable groundwater management. However, groundwater management in the CB faces numerous challenges.

This challenge centers on Jordan’s worsening water crisis, one of the most severe globally. The country faces chronic water scarcity due to naturally low rainfall, limited renewable water sources, and rapid population growth. The crisis is further intensified by climate-driven droughts and unsustainable groundwater extraction, which together threaten long-term water security. The challenge aims to develop space-based monitoring and management strategies to better understand, predict, and mitigate the compounding impacts of drought and groundwater depletion on national water systems.