This research conducted a citizen scientific field investigation and water quality assessment of nine major rivers using only on-site equipment and a smartphone in the Province of Antique, Philippines. Potential issues concerning water resources management in the province were discussed with local governors and citizens while conducting the water sampling and on-site measurement. The results of water quality assessments revealed that some of the rivers have experienced high turbidity, caused by anthropogenic activities such as embankment, sand mining, and dredging. In highly populated basins, such as the Sibalom and Malandog Rivers, a high biochemical oxygen demand level (>7 mg/L) was confirmed by the water quality analysis using an iPhone. Since high consumption of groundwater has already affected the lives of people in the province, surface water usage shifting from groundwater, involving the construction of a facility treating physical and chemical parameters, is needed. The citizen scientific approach employed in this research can provide more realistic insights into local environmental concerns, which would not be possible through quantitative measurements of water quality.

This research assessed water quality, based on the purpose of water consumption, in households in the municipality of Barbaza, the Province of Antique, Philippines, according to the national water quality guidelines. The effects of the empirical/traditional water use actions taken by local people on the quality of the water they use were investigated through a descriptive study using water quality measurements. Most of the drinking water in the community did not meet the required standards of pH, total dissolved solids (TDS), or coliform. Tap water and well water samples generally met the pH and TDS standards. However, Escherichia coli (E. coli) and coliform were detected, and nitrogen pollution in well water was also confirmed. Local practices, such as using old clothes as filters for well pumps, increased the coliform concentration from 0–10 CFU/mL to too numerous to count (TNTC) levels of more than 100 CFU/mL. Storing well water in a bucket also affected both E. coli and coliform concentrations. Such empirical/traditional water use actions create a high risk of exposing local people to harmful microorganisms. This research integrated citizen science into the methodology for local water management, which could assist governors, practitioners, and citizens, particularly in Southeast Asia, where strong community relationships exist.

This research investigated the historical changes in basin-scale rainfall characteristics and their spatial distributions in the Lake Biwa and Yodo River Basin. Nine rainfall indices including two general and seven extreme rainfall indices and the probable rainfall according to 50- and 100-year return periods were evaluated based on the data gathered from 61 rain gauge stations. The regionalization of the rainfall indices and probable rainfall was then examined using spatial interpolation via the Kriging method. The results of the spatial analysis for the rainfall indices showed that there is a potentially high risk of extreme rainfall events and pluvial floods, particularly in the northern, western, and southern areas. The 50- and 100-year probable rainfall has historically increased in the north through to the western area of the basin. The return periods of the 50- and 100-year rainfall events decreased in the northern area of Lake Biwa and the western area of the basin. The findings of this research suggest that the local flood management plan needs to be updated depending on the regional differences in extreme rainfall characteristics. In basins/areas with sparsely distributed rain gauge stations, regionalization can provide useful information as part of local flood management planning.

The use of smartphones in assisting with water quality measurement enables us not only to collect quantitative environmental information but also to use smartphones as an environmental education and management tool. In this study, we evaluated the performance of a smartphone-based water quality monitoring method, known as the SMART PACKTEST, for environmental assessments. Specifically, we measured nitrogen parameters (ammonium-nitrogen (NH4-N), nitrite-nitrogen (NO2-N), and nitrate-nitrogen (NO3-N)) using the SMART PACKTEST with an iPhone 12 Pro Max and compared the results to those obtained using the DIGITAL PACKTEST, which uses a simplified portable absorption spectrophotometer. The water samples analyzed were collected from the Komaba-ike Pond at the University of Tokyo. The SMART PACKTEST tended to overestimate NH4-N and NO3-N concentrations by 1.5 to 2.6 times, respectively. However, the results obtained by the two methods showed good agreement, with the pseudo coefficients of determination being 0.96–0.98. This suggests that the SMART PACKTEST could be used for preliminary investigations to determine overall spatial/temporal water quality trends in the target area rather than for collecting accurate data. Further research is needed to confirm the applicability of this smartphone-based water quality monitoring method, particularly in developing regions with diverse water conditions.

In the Philippines, the Ecological Solid Waste Management Act (RA 9003) designates solid waste management as an essential service that municipal authorities provide to maintain environmental cleanliness. However, current waste management systems are unscientific, outdated, and inefficient. Furthermore, it remains unclear whether RA 9003 effectively reaches rural and remote areas of the country. This research explored barangay-level waste management strategies in Barbaza, Antique, using a comprehensive field survey involving government data collection and interviews with barangay leaders and residents. The findings revealed that a total of 37.6 tons of waste was collected in 2024, but garbage trucks still fail to reach all remote barangays. Despite efforts like establishing materials recovery facilities and community composting campaigns, greater public engagement and education are necessary to achieve a cleaner, safer environment. This paper proposes future directions for improving waste management practices in communities based on successful strategies modeled elsewhere in Antique.

This research presents a comprehensive citizen-scientific water quality assessment and evaluation, focusing on water quality at the points of water consumption in public and private high school campuses in the Province of Antique, Philippines. The water quality assessment showed that Escherichia coli was detected in several samples from tap water exclusively used for handwashing by public school students, indicating potential contamination sources such as outdated treatment facilities. To improve the WASH environment of the provincial school campuses, old facilities, such as filters and pipes, need to be checked and renovated to avoid contamination caused by penetration and leakage. School-level and individual practices, such as chlorination, covering water tanks, and encouragement of handwashing, could be the first step. The citizen scientific methodology facilitated the collection of water quality information and enhanced discussions with stakeholders, generating practical and affordable solutions based on the findings.