The archipelagic Romblon province frequently experiences typhoons and heavy rains that causes extreme flooding, this produces particular concern about the severity of damage in the Municipality of Odiongan. Hence, this study aimed to assess the spatial flood risk of Odiongan using the analytical hierarchy process (AHP), considering disaster risk factors with data collected from various government agencies. The study employed the geographic information system (GIS) to illustrate the spatial distribution of flooding in the municipality. Sendai Framework was the basis of risk analysis in this study. The hazard parameters considered were average annual rainfall, elevation, slope, soil type, and flood depth. Population density, land use, and household number were considered parameters for the exposure assessment. Vulnerability assessments considered gender ratio, mean age, average income, number of persons with disabilities, educational attainment, water usage, emergency preparedness, type of structures, and distance to evacuation area as physical, social, and economic factors. Each parameter was compared to one another by pairwise comparison to identify the weights based on experts’ judgment. These weights were then integrated into the flood risk assessment computation. The results led to a flood risk map which recorded nine barangays (small local government units) at high risk of flooding, notably the Poblacion Area. The results of this study will guide local government units in developing prompt flood management programs, appropriate mitigation measures, preparedness, and response and recovery strategies to reduce flood risk and vulnerability to the population of Odiongan.

The unique two-dimensional structure and chemical properties of graphene oxide (GO) provide a convenient method for preparing novel membranes. In this study, GO membranes were prepared through filtration by a pressure-assisted self-assembly method involving the cross-linking of three diamine monomers on a polyethersulfone (PES) support. The different small molecular diamines, ethylenediamine, butanediamine, and p-phenylenediamine, were introduced as cross-linking agents to investigate the effect of diamine on the properties of GO membranes. The hydrophobic substances ibuprofen, gemfibrozil, and triclosan were selected as target pharmaceuticals and personal care products (PPCPs). The adsorption and molecular sieving activities of PPCPs by cross-linked GO membranes at a pH of 3 were investigated. The permeate water was analyzed for dissolved organic carbon, ultraviolet absorption at 254 nm, molecular weight distribution, and fluorescence excitation–emission matrices. The results showed that the removal of hydrophobic PPCPs by GO membranes was mainly due to their adsorption and molecular sieving activities. Adsorption was mainly determined by the hydrophilic and hydrophobic properties of the membranes and PPCPs. The interception effect was mainly determined by the interlayer spacing between the GO membranes and the molecular weight and steric hindrance of the PPCPs. A smaller spacing of the GO membrane layers resulted in greater steric hindrance and a higher removal rate.

Floods are among the most devastating natural hazards, causing widespread damage to lives, livelihoods, and infrastructure, particularly in vulnerable river basins. The Cagayan River Basin (CRB), the largest and most flood-prone basin in the Philippines, remains a significant challenge for disaster risk management. This study developed an event-based hydrologic–hydraulic modeling framework by coupling HEC-HMS rainfall–runoff simulations with HEC-RAS 2D unsteady flow routing to produce validated flood hazard maps. Inputs included rainfall from 41 gauge stations and observed inflows from the Magat Dam, processed in HEC-DSS. Validation utilized 137 surveyed flood marks collected from post-flood surveys, community reports, government archives, and household RTK measurements, with a concentration in Tuguegarao City. The coupled model reproduced key hydrograph peaks with moderate accuracy (R² = 0.56, Bias = +0.32 m, RMSE = 1.61 m, MAE = 1.43 m), although NSE (−2.30) reflected the limits of daily rainfall inputs. Simulated hazard maps identified 767.97 km² of inundated area (approximately 2.77% of CRB), concentrated along the floodplain and at the Magat confluence. Unlike previous scenario-based or localized efforts, this study delivers the first basin-wide, event-validated flood hazard maps for the CRB using integrated depth and depth–velocity criteria. The resulting hazard layers provide a scientific basis for strengthening evacuation planning, guiding land-use and infrastructure decisions, and supporting long-term resilience strategies in one of the Philippines’ most flood-prone rivers.

Hydrologic and hydraulic model applications for floodplain analysis are very limited in the Philippines due to the insufficiency of topographic, river geometric and hydrologic data. However, with Light Detection and Ranging (LiDAR) technology, the country is able to overcome this problem resulting to much more accurate mapping and modeling possibilities. With the use of a modern hydrologic modelling software, rainfall runoff model based on LiDAR data was created for Malaking-Ilog River in Batangas-Quezon with precipitation input of five, ten, twenty-five, fifty and a hundred-year return period. In this study, the significance of the hydrologic model and the selection of return period in the design of various water related structures were discussed. Moreover, river analysis software was utilized in a case study for design of a dike. The communities which are politically grouped as "barangays" surrounding the river that are directly affected when the river overflows were identified. With the help of the hydrographs generated from the rainfall runoff model in this study, the design parameters of various water related structures are easily determined leading to a more efficient design process.

Brine generated from seawater desalination presents significant environmental challenges due to its high salinity and pollutant content, particularly when discharged without adequate treatment. While advanced brine treatment systems offer opportunities for resource recovery and pollution reduction, they often involve increased energy and material demands, creating trade-offs between environmental benefits and resource consumption. This study integrates Water Footprint Assessment (WFA) and Life Cycle Assessment (LCA) to evaluate the freshwater sustainability of circular brine treatment systems under different process configurations. The framework is applied to four treatment scenarios, including variations in precipitation agents (NaOH and Ca(OH)₂) and the inclusion of calcination processes, and compared with a reference scenario representing direct brine discharge. The results show that the blue water footprint is primarily driven by indirect water use associated with energy consumption, while pollutant loads influence the grey water footprint. Although advanced scenarios increase gross water demand, significant reductions are achieved through avoided water contributions from resource recovery and internal water reuse. Among the evaluated configurations, Scenario 2 exhibits the highest total water footprint due to elevated energy and pollutant-related impacts, whereas Scenarios 3 and 4 demonstrate improved performance through enhanced recovery efficiency. The water–carbon trade-off analysis highlights that minimizing carbon emissions does not necessarily reduce water consumption, emphasizing the importance of integrated assessment. Overall, the findings demonstrate that sustainable brine treatment design requires balancing water use, pollution control, energy demand, and resource recovery. The proposed WFA–LCA framework provides a robust decision-support tool for optimizing circular brine management systems.