Location tagging of groundwater sources for irrigation using GIS in the Municipality of San Lorenzo, Guimaras

Abstract

A Geographic Information System (GIS) was used to create a thematic map and pattern distribution analysis of groundwater sources in San Lorenzo, Guimaras. The study examined the groundwater sources used by vegetable farmers in San Lorenzo, focused on the service area, availability of groundwater sources, and crop area for cultivation within the municipality. The study found that 52 vegetable crop farmers in ten active barangays predominantly use groundwater sources for irrigation. The service area used by these farmers is 40.03 ha, with Brgy. Constancia and Cabano have the highest usage. The service areas range from 0.25 ha to 2.5 ha, with 1.1 to 2.5 ha being mostly utilized in the lowland portion of the municipality. During the dry season, groundwater sources are most abundant in lowland areas with low water tables and near rivers. High availability areas were found in Cabano, M. Chavez, Suclaran, Cabungahan, Sebario, and some upland areas like Gaban and Constancia. Upland areas had few available sources due to deep-water tables. The study classified groundwater tube wells used for irrigation: shallow tube wells were highly utilized in lowland areas and areas near watersheds with low water tables, while deep tube wells were used in upland areas with a deep-water table. The study revealed that San Lorenzo's areas are primarily used for planting fruit-bearing vegetables, with upland areas using leafy vegetables. The lowlands are most utilized for fruit-bearing vegetables and some for leafy. The study also revealed that the status and location of groundwater sources in San Lorenzo are clustered, as indicated by the pattern distribution analysis.