Identifying suitable sites for pump irrigation system from open source and shallow tube well in selected areas of Davao Del Sur through geographic information system-based water resources assessment

摘要

This paper features the Geographic Information System (GIS) in identifying suitable sites for small scale irrigation projects (SSIP) particularly pump irrigation system from open source (PISOs) and shallow tube well (STW) through water resource assessment. The development of GIS-based assessment model for SSIP and resource map in aid of SSIP planning and development is limited in some municipalities. To develop a reliable GIS-base framework, the ArcGIS tool and spatial method was used in compiling specific factors with field analysis and developing regional resource map for SSIP. The results showed that STW in Digos City and Municipality of Hagonoy is 117 units and 17 units respectively. The average water depth in existing STW is within the 6.5 meters with capacity to irrigate 3 to 5 hectares per unit, low investment with high water use efficiency and simple to operate. It was found out that most STW is provided by Department of Agriculture-Regional Field Office XI and Local Government Units. The STW is suitable for Digos City with an area of 379.32 hectares. While the PISOS were identified with different range of pump horsepower. There are 10 units of PISOS in Digos City and 15 units in Hagonoy mostly provided by National Irrigation Administration-XI. It was found out that in Digos City the 1,855.53 hectares are highly suitable and 14,377.55 hectares are not suitable for PISOS. The results of this study may assist the decision making processes for planning and development of SSIP using the developed protocol and tools for different purpose in agricultural production in Davao del Sur, Region XI and the whole country.