Spring

Place where water flows natural from a rock or soil onto land, or into a body of surface water (United Nations Publication, 2013)
 

Sources

United Nations Publications. "Glossary of Shared Water Resources (English-Arabic): Technical, Socioeconomic and Legal Terminology." (2013). DOI:https://dx.doi.org/10.18356/70b462ce-en
 

Related Content

Article

Interview with Alicia Simón Sisimit, Kaqchikel Journalist and activist at DDASO Project

Interview with Alicia Simón Sisimit, Kaqchikel Journalist and activist at DDASO Project

DDASO project team conducting field work

Short description of the Kaqchikel community

The municipality of San José Poaquil was founded on November 1, 1891. It is located in the department of Chimaltenango with a territorial extension of approximately 100 km² and has almost 30 000 inhabitants. It is one of the 16 municipalities that make up the department of Chimaltenango. It is located in the west of the Republic of Guatemala at a distance of 101 kilometers from the Capital City and distance 47 kilometers from the Departmental Capital.

Read More

Interview with Alicia Simón Sisimit, Kaqchikel Journalist and activist at DDASO Project

Interview with Alicia Simón Sisimit, Kaqchikel Journalist and activist at DDASO Project

DDASO project team conducting field work

Short description of the Kaqchikel community

The municipality of San José Poaquil was founded on November 1, 1891. It is located in the department of Chimaltenango with a territorial extension of approximately 100 km² and has almost 30 000 inhabitants. It is one of the 16 municipalities that make up the department of Chimaltenango. It is located in the west of the Republic of Guatemala at a distance of 101 kilometers from the Capital City and distance 47 kilometers from the Departmental Capital.

Read More

Local Perspectives Case Studies

Need for technical assistance to identify new water sources such as springs within the forest, in Guatemala

Honouring Andes's water heritage: bridging traditional knowledge and technology for ancestral water sources management in Quilloac, Ecuador

Water availability and management strategies for spring-dependent smallholder farms in southwest Kyrgyzstan

Water availability and management strategies for spring-dependent smallholder farms in southwest Kyrgyzstan

A view of the Khojabakirgan River flowing through the village of Layli in Leilek District, Kyrgyzstan. The river winds through a broad valley with scattered trees, farmland, and dry hills under a clear blue sky.
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.
Read More

The ecohydrological trade-off in Nepal’s Middle Hills: mapping spring decline and groundwater loss in community forests through space-based solutions

The ecohydrological trade-off in Nepal’s Middle Hills: mapping spring decline and groundwater loss in community forests through space-based solutions

Map of Sharadha Khola watershed in Nepal
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.
Read More

Space-based Solution

Satellite-based ecohydrological analysis for spring revival in Nepal's Middle Hills - in development and need for input

Addressed challenge(s)
Map of Sharadha Khola watershed in Nepal

The ecohydrological trade-off in Nepal’s Middle Hills: mapping spring decline and groundwater loss in community forests through space-based solutions

Collaborating actors (stakeholders, professionals, young professionals or Indigenous voices)
Suggested solution

This solution combines multi-source satellite remote sensing, ecohydrological modeling, and community science to address spring decline and water insecurity caused by afforestation and land-use changes in Nepal's Middle Hills. The integrated approach offers a pathway to scientifically informed, community-driven forest and water management.

  1. Satellite Data Fusion: The first core strategy involves fusing multi-temporal and multi-sensor satellite data to assess vegetation trends, hydrological changes, and potential spring recharge zones.
  • Vegetation Monitoring: Time-series NDVI, EVI, and LAI are derived using Sentinel-2, Landsat, NOAA and MODIS. These indices help detect vegetation growth trends and assess forest types based on phenological signatures.
  • Cloud Mitigation: Nepal’s rugged terrain and monsoon conditions create persistent cloud cover challenges. While no perfect cloud-removal technique exists, we aim to apply machine learning and established algorithms like CLAY3 or Fmask to improve data quality for vegetation and land cover analysis.
  • Hydrological Metrics: ET using MODIS, Soil moisture is mapped using SMAP data, downscaled using terrain parameters such as slope and elevation. GRACE data informs groundwater trends. Satellite-based precipitation datasets are validated against DHM station data to compensate for missing or sparse in-situ observations.

 

  1. RHESSys Ecohydrological Simulation: The RHESSys model simulates the complex interactions between vegetation, soil moisture, surface and subsurface water flow, and groundwater storage. The model is run in growth mode to evaluate how forest type changes influence spring discharge.
  • MODIS ET and Sentinel-1 soil moisture serve as validation inputs.   
    The model provides spatial outputs including groundwater depth, lateral flow, and baseflow dynamics—critical for delineating micro-watersheds and assessing recharge efficiency.

 

  1. Recharge Zone and Spring Hotspot Mapping: Topographic indices such as TWI (Topographic Wetness Index) and HAND (Height Above Nearest Drainage), derived from ASTER DEMs, are used to identify spring recharge zones.
  • These zones are further validated using RHESSys outputs, satellite data layers, and available field measurements.
  • Machine learning (e.g., Random Forest) and participatory mapping help cross-check locations of active and declining springs.
  • The resulting maps guide protection measures and afforestation policies targeting hydrologically sensitive areas.

 

  1. Field Validation and Community Co-Design: Local participation through spring monitoring and mapping ensures the integration of indigenous knowledge with scientific analysis. Field measurements validate model predictions and support community-driven management strategies.

 

Requirements

Data

  • Remote sensing: NDVI, EVI, LAI, Evapotranspiration (MODIS), Soil Moisture (SMAP), satellite-based precipitation, terrestrial Groundwater storage (GRACE), Land Use Land Cover, DEM (ASTER).
  • In-situ: Precipitation and temperature data from DHM Nepal

Software

  • Google Earth Engine (cloud computing, satellite data analysis)
  • GRASS GIS and QGIS (terrain analysis, TWI, HAND)
  • RHESSys (eco-hydrological modeling)
  • R/Python (statistical modeling, ML integration)
  • LEAF Toolbox for LAI/phenology

Physical Requirement

  • Cross-validation of spring locations and groundwater depth measurements through field visits.

Priority Support Areas: To realize objectives, we seek support in the following areas:

  • High-Resolution and Cloud-Free Satellite Data: Technical assistance in accessing and processing Sentinel-1 SAR, Sentinel-2, and Landsat data, and applying cloud-removal algorithms.
  • Downscaling Remote Sensing Products: Assistance in refining MODIS-based NDVI, EVI, LAI, and phenological indicators using auxiliary terrain and land cover datasets.
  • Integration of Hydrological and Remote Sensing Data: Guidance on synchronizing outputs from RHESSys with MODIS, SMAP, and GRACE datasets for robust cross-validation.
  • Mapping Recharge and Spring Zones: Technical support in combining terrain indices with RHESSys-derived metrics to map spring recharge zones and inform land-use planning.

 

Outline steps for a solution

Phase 1: Satellite Analysis and Vegetation Mapping (completed)

 

Phase 2: GIS and Terrain Modeling (In Progress)

  • Use DEM, LULC, TWI, HAND for recharge/discharge mapping.   
    Analyze terrain factors (slope, curvature, aspect, valley) for moisture prediction.

 

Phase 3: Hydrological Simulation and Analysis (To Do)

  • Run RHESSys in growth mode to simulate hydrological-vegetation dynamics.
  • Validate against spring discharge logs.
  • Output: groundwater depth, saturation deficit, soil moisture, flow trends, seasonal water availability.

 

Phase 4: Community Co-Design and Policy Translation (To Do)

  • Share vulnerability maps with CFUGs and municipal planners.
  • Recommend native species afforestation rather than heavily water dependent species.
  • Promote thinning, selective logging, litter removal, etc. (forest management plant).
  • Water availability zone mapping for settlement

 

RHESSys model

Note: "The full code and comprehensive instructions for running the model are provided in this repository."

Results

  • Preliminary analysis shows increasing trends in both evapotranspiration and LAI, indicating higher water consumption by vegetation and less water available for downstream use. 
  • Mapped recharge zones and high-risk spring areas.
  • Groundwater storage trends over time and identification of water-available zones suitable for settlement planning.
  • Spatial maps and hydrologic models to support forest and water governance.
  • Policy briefs on forest-water tradeoffs and spring recovery.
  • Community awareness on how certain forest types and species are accelerating water loss and increasing water stress for downstream communities, prompting migration.
  • Technical findings paired with management strategies offer actionable insights for land-use planning and ecosystem resilience.
Leaf Area Index of Sharada Khola Watershed

 

Evapotranspiration for Sharadha Khola Watershed
Relevant publications
Related space-based solutions
Keywords (for the solution)
Remote SensingGroundwater rechargeSpringNormalized Difference Vegetation Index (NDVI)EvapotranspirationEcohydrology
Climate Zone (addressed by the solution)
Dry winter subtropical highland
Habitat (addressed by the solution)
Mountain habitats
Region/Country (the solution was designed for, if any)
Nepal
Relevant SDGs