Basumatary et al. (2026) From hillslope runoff to channel migration: A multi-scale decision-support framework for sustainable water management in an Eastern Himalayan foothill region

Identification

• Journal: Journal of Hydrology Regional Studies
• Year: 2026
• Date: 2026-09-07
• Authors: Sagar Basumatary, Soumen Maji
• DOI: 10.1016/j.ejrh.2026.103950

Research Groups

• Department of Civil Engineering, Central Institute of Technology Kokrajhar, Kokrajhar, Assam, India
• Geological Survey of India

Short Summary

This study presents a multi-scale hydrological assessment to support sustainable water management in the Eastern Himalayan foothill region. The research combines surface runoff estimation, groundwater-potential assessment, basin-scale hydrological simulation, and riverbank-migration analysis to provide complementary evidence for regional water-resource management.

Objective

• To develop a multi-scale decision-support framework for identifying runoff-prone areas, groundwater-potential zones, hydrologically sensitive areas, and erosion-prone river reaches in the Eastern Himalayan foothill region of Baksa District.
• To synthesize event-based runoff generation, regional groundwater potential, basin-scale hydrological behaviour, and river morphodynamics within a common regional assessment.

Study Configuration

• Spatial Scale: The study was conducted at multiple spatial scales, including the Pagladiya watershed (ungauged), the Beki River Basin (gauged), and Baksa District.
• Temporal Scale: The temporal coverage of the study ranges from 2008 to 2023 for rainfall data and 2011–2020 for calibration and validation of the SWAT model.

Methodology and Data

• Models used:
  • Soil Conservation Service Curve Number (SCS-CN) method for event-based runoff estimation.
  • Geographic Information System (GIS)-based Analytical Hierarchy Process (AHP) for groundwater-potential assessment.
  • Soil and Water Assessment Tool (SWAT) for basin-scale hydrological simulation.
  • Digital Shoreline Analysis System (DSAS) for riverbank-migration analysis.
• Data sources:
  • Topographic, meteorological, hydrological, soil, geological, land-use/land-cover, and satellite datasets.

Main Results

• Mean runoff across the Pagladiya sub-watersheds ranged from 71.73 to 114.07 mm, with greater runoff generation observed in downstream sub-watersheds.
• Groundwater assessment indicated that approximately 56.4% of Baksa District possesses moderate-to-high groundwater potential, predominantly within the alluvial plains.
• The calibrated SWAT model satisfactorily reproduced observed streamflow dynamics (NSE = 0.82 and 0.78; R² = 0.86 and 0.81 for calibration and validation, respectively).
• DSAS analysis revealed persistent riverbank instability and pronounced lateral channel migration, particularly along downstream reaches, with lateral displacement exceeding 39 m in the most unstable downstream zone.

Contributions

• This study provides a multi-scale decision-support framework for identifying runoff-prone areas, groundwater-potential zones, hydrologically sensitive areas, and erosion-prone river reaches.
• The research synthesizes event-based runoff generation, regional groundwater potential, basin-scale hydrological behaviour, and river morphodynamics within a common regional assessment.

Funding

• This study was funded by [project/program name] with reference code [reference code].

Citation

@article{Basumatary2026From,
  author = {Basumatary, Sagar and Maji, Soumen},
  title = {From hillslope runoff to channel migration: A multi-scale decision-support framework for sustainable water management in an Eastern Himalayan foothill region},
  journal = {Journal of Hydrology Regional Studies},
  year = {2026},
  doi = {10.1016/j.ejrh.2026.103950},
  url = {https://doi.org/10.1016/j.ejrh.2026.103950}
}