The study was conducted to assess land uses and infrastructures in the Pinacanauan de San Pablo Watershed. The methods used were review and analysis of existing maps and development plans; site assessment using photo documentation, site observation and informal interviews; gathering of secondary data at the local government unit at San Pablo, Department of Environment and Natural Resources and National Irrigation Administration; preparation of base maps i.e., road and irrigation maps. The watershed covers thirteen (13) barangay: i.e., eight in San Pablo, Isabela with an area of 29,272.85 hectares, four in Cabagan, Isabela with an area of 449.87 hectares, and one in Peñablanca, Cagayan with an area of 4,280.87 hectares. It has an aggregate area of 33,553.72 hectares. Its vast aquatic resources include the Cagayan River and the tributaries like the Pinacanauan River in the center, and Balulu Creek in the south as source of fish, transport and irrigation water. The infrastructures found in the watershed like irrigation facilities and road network were poorly managed and have not been fully operational due to the effects of weather disturbances. With the occurrence of flood during the rainy season, watershed degradation takes place due to soil erosion, sedimentation, and landslides that affects the productivity of the land. This result to unstable surface run-off that floods lower areas and leads to low agricultural yield, loss of income and induced poverty.