Envisioning a Sustainable Water Resource Governance in the Sambunotan Watershed: Integrating GIS, Hydrology, Geology, and Water Quality Insights

Meriam Makinano-Santillan; Arnaldo Gagula; Rowena Varela; Jojene Santillan

doi:10.54610/jeseg.v6i2.119

Authors

Meriam Makinano-Santillan Caraga Center for Geo-informatics, Caraga State University, Ampayon, Butuan City 8600, Agusan del Norte, Philippines, Department of Geodetic Engineering, College of Engineering and Geosciences, Caraga State University, Ampayon, Butuan City 8600, Agusan del Norte, Philippines
Arnaldo Gagula Caraga Center for Geo-informatics, Caraga State University, Ampayon, Butuan City 8600, Agusan del Norte, Philippines, Department of Geodetic Engineering, College of Engineering and Geosciences, Caraga State University, Ampayon, Butuan City 8600, Agusan del Norte, Philippines
Rowena Varela Caraga Center for Geo-informatics, Caraga State University, Ampayon, Butuan City 8600, Agusan del Norte, Philippines, Department of Plant and Soil Science, College of Agriculture and Agri-Industries, Caraga State University, Ampayon, Butuan City 8600, Agusan del Norte, Philippines
Jojene Santillan Caraga Center for Geo-informatics, Caraga State University, Ampayon, Butuan City 8600, Agusan del Norte, Philippines, Department of Geodetic Engineering, College of Engineering and Geosciences, Caraga State University, Ampayon, Butuan City 8600, Agusan del Norte, Philippines, Institute of Photogrammetry and GeoInformation, Leibniz University Hannover, Nienburger Str. 1, 30167 Hannover, Germany

DOI:

https://doi.org/10.54610/jeseg.v6i2.119

Keywords:

Sustainable Water, Watershed Governance, Sambunotan Watershed, GIS, Hydrological Analysis, Geological Mapping, Water Quality Assessment, Watershed Management

Abstract

KEY POINTS

● The Sambunotan Watershed is essential for water supply, agriculture, and biodiversity in northern Dinagat. However, it faces natural and man-made disruptions that include deforestation, mining, unsustainable farming, and climate variability, putting ecosystem services and the community well-being at risk.

● A revised watershed boundary corrected discrepancies in earlier delineations and revealed that the Sambunotan River is not its primary tributary.

● With approximately 70% of the watershed classified as Alienable and Disposable (A&D), 30% as timberland, and no protected areas, combined with mining tenements covering more than 75% of its area, the watershed is highly vulnerable to environmental degradation.

● Hydrological modeling highlighted seasonal water dynamics, with a total baseflow of 71.60 million cubic meters (MCM), while water quality analysis linked land use, particularly tree cover, to improved water parameters, underscoring the need for sustainable land-use practices.

● Key recommendations include designating protected areas or local conservation areas, regulating mining and land use in A&D zones, improving water and sediment monitoring, enhancing reforestation in riparian zones, and renaming the watershed to align governance with its true ecological and hydrological features.

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