wcm.01.2026.32.37

Water management in tropical highlands always presents challenges, especially in intensive horticultural lands that experience degradation of soil structure and affect groundwater infiltration. This research method was carried out by surveying the soil with 13 location points. Through infiltration measurements at 13 points and nine-year rainfall analysis in the Twin Lakes area. The data were analyzed statistically descriptive, then looked at the relationship between soil properties and infiltration. The results of the study found that the soil infiltration capacity was much lower than expected for volcanic soils. The measured infiltration was only 0.30– 4.92 cm h⁻¹, while the annual rainfall routinely exceeded 2,000 mm. From field observations and statistical analysis, soil compaction (high bulk density) and decomposition of organic matter play a major role in suppressing infiltration. A strong negative correlation between infiltration and bulk density (r = –0.78) as well as a positive correlation with porosity (+0.71) and C-organic (+0.65) confirmed this relationship. This condition creates a hydrological imbalance, especially in the peak rainy months (November–December) when the soil is often in a post-harvest open state. These findings point to the need for the immediate adoption of conservation measures such as organic mulching, minimum tillage, and vegetative barriers to restore infiltration capabilities and reduce erosion in steep-sloped horticultural areas.