The sources of plastic wastes and areas of expected high levels of plastic waste generation were mapped in the Imus River Watershed in the Province of Cavite, in the Philippines. Different sources of plastic waste were identified, and used to estimate the magnitude of plastic waste generation. Information on the major sources of plastic waste were obtained from the 10-Year Solid Waste Management Plan of the seven cities and municipalities located within the boundaries of the watershed. Remote sensing technology was used to identify the coordinates of different potential sources. For higher resolution, Google Imagery was used in preparing base maps which were imported and georeferenced in ArcMap. A 7-day waste characterization study in three selected barangays was conducted to determine the average amount of plastic waste generated per household. This data served as inputs for a hotspot analysis in ArcGIS to identify plastic waste generation hotspots within the watershed. The Imus River system traverses seven cities and municipalities that include parts of Tagaytay City, Silang, and Amadeo in the upland areas, a large part of the densely populated and urbanized cities of Dasmariñas and Imus City in the central hilly areas, and portions of the lowland City of Bacoor and the coastal Municipality of Kawit. It has a total drainage area of 11,259.80 hectares. A total of 222 barangay communities were identified within the boundaries of the watershed with a total population of 1,351,057. The major sources of waste in the watershed were primarily households, followed by commercial, institutional, and industrial establishments. The total number of commercial, institutional, and industrial establishments identified was 778, and a total of 54 waste storage facilities were found in the watershed. From the 7-day characterization study in three selected barangay communities, an average of 113.03 kg of plastics was generated daily by the households in Barangay Burol 1, Dasmariñas City; 9.17 kg/day in Barangay Mabolo 1, Bacoor City; and 29.29 kg/day in Barangay Maitim 2nd Central, Tagaytay City. An average of 0.17 Kg/day per household of plastics were generated in the watershed and 0.05 Kg/day per capita.  A cluster of high plastic waste generating barangays was identified in Dasmariñas City, where various tributaries of the Imus River converge. This combination is likely to create a significant hotspot for waste leakage. Clusters of low plastic waste generating barangays were identified in parts of Imus, Kawit, and Bacoor. These cold spots should not be ignored, as increasing plastic waste generation could exceed capacity and push them into future leakage hotspots.

With technical guidance/assistance from PRF, NIVA, and other partners, DLSU-D conducted a survey on plastic litters in the waters of the Imus River located in at least one barangay of five cities/municipalities (Municipality of Silang, City of Dasmariñas, City of Imus, City of Bacoor, and Municipality of Kawit). The data in this report were based on on-site observations and the collection of plastic litters during dry and wet months using. Both visual and active trawl sampling methods were used. Sampling sites were selected to represent the upstream, midstream and downstream of the entire stretch of the river located along five (5) municipalities/cities.

This study tackles the Imus River, one of the six major river systems in the province of Cavite. The main river is 38.4 kilometers long and stretches from Tagaytay City in the northern upland region, through the municipality of Silang, the cities of Dasmariñas, Imus, and Bacoor, and lastly the lowland areas of Bacoor and the municipality of Kawit, where it empties into Bacoor Bay. Within these cities/municipalities are barangays that find the river useful for domestic, tourism, and industrial purposes. DLSU-D surveyed different stakeholders (households, LGUs, and households with small businesses) in 14 selected barangays in the five cities/municipalities (Silang, Dasmariñas City, Imus City, Bacoor City, and Kawit) located along the Imus River. This study determined the stakeholders’ knowledge, attitudes, and practices (KAP) related to plastic pollution problems including its impact, management, and their reasons for using plastic. It also assessed the economic value of the river to the community by identifying and analyzing economic benefits like employment, livelihood, goods, and services derived from the Imus River. Lastly, it determined the Ability to Pay (ATP) and Willingness to Pay (WTP) for better waste and pollution management of the selected communities dependent on the river for their day-to-day needs. Both quantitative and qualitative data were obtained for the study through surveys and interviews. Recommendations for a community-based plastic waste management program were made based on the collected data on KAP, ATP, and WTP of different stakeholders.

This study investigates the socioeconomic implications of plastic waste pollution mitigation initiatives near the Imus River, which traverses through the province of Cavite. It explores initiatives identified by the communities on plastic waste management and consequently examines how these initiatives are managed and implemented. It also describes the communities’ culturally nuanced understanding of plastic waste management, as well as the implications of such management to Cavite residents. The data is gathered from five sites traversed by the Imus River, in selected barangays in (upstream to downstream) Silang, Dasmariñas, Imus, Bacoor, and Kawit. The methods used were concurrent triangulation of quantitative and qualitative data, a survey of 300 residents, and in-depth interviews of 20 key informants from different sectors in the community. Other sources of data, i.e., local documents, online and on-site focus group discussions (FGDs), and direct observations complemented the survey results.

Both primary and secondary data sources were used to make comprehensive land use maps, population maps, and hydro-climatic data analyses. The boundary of the Imus River watershed was established using a digital elevation model of the province of Cavite in ArcGIS. Sangley Point Synoptic Station in Cavite and the CvSU-PAGASA Agrometeorological Station in Indang were used to assess the general hydro-climatic condition of IRW due to their close proximity to the watershed.

The study investigates the socioeconomic implications of plastic waste pollution mitigation initiatives along the Imus River, which traverses the Philippine province of Cavite. It explores initiatives identified by local communities on plastic waste management and examines how these initiatives are managed and implemented. It also describes the various communities’ culturally nuanced understanding of plastic waste management as well and its implications to them as Cavite residents. It is based on reports commissioned by the ASEANO project to help Local Government Units (LGUs) better understand the plastics pollution problem and develop practical and enforceable solutions.

This study mapped the sources and concentration of plastic waste in the Imus River watershed, which lies in the Philippine province of Cavite. It aimed to identify different origin points for plastic waste, and determine the magnitude of plastic waste generation within the watershed. A seven-day waste characterization study in three selected barangays was conducted to determine the average amount of plastic waste generated per household.

This study targeted communities along the Imus River, one of six major water sources in the province of Cavite, a rapidly-developing province south of Manila. It determined the stakeholders’ knowledge, attitude and practices related to plastic pollution problems including the impact, management and the communities’ reasons for using plastic products. It assessed the economic value of the river by identifying and analyzing economic benefits like employment, livelihood, plus goods and services derived from the river. Lastly, it determined the ability to pay and willingness to pay of the selected communities dependent on the river for people’s daily needs.

This study assesses the extent of plastic pollution in the Imus River by quantifying and characterizing macroplastics and microplastics. The water quality of the river was also assessed based on its physicochemical characteristics to confirm the Class-C (intended for fisheries, agriculture, and recreational use) classification of the river per DENR standards. Physicochemical parameters were correlated to the quantities of collected plastic litter.