Water Resources Research Act Program

Details for Project ID GU_2023_KIM_1

Water Quality Monitoring of Agana Swamp on Guam

Institute: Guam
Year Established: 2023 Start Date: 2023-09-01 End Date: 2024-08-31
Total Federal Funds: $20,792 Total Non-Federal Funds: Not available

Principal Investigators: Yong Sang Kim

Project Summary: Agana Swamp is located near the village of Hagatna, one of the most developed and populated areas in Guam. Agana Swamp originates from Agana Spring and occupies the lowlands of the Agana-Choat river basin, encompassing Guam's largest wetland area. The swamp is beneficial as it can intercept runoff and store or transform possible pollutants. However, elevated levels of contaminants can adversely affect both benthic organisms and water quality. Examples of organic pollutants are polychlorinated biphenyls (PCBs) and perfluorooctanesulfonic acid (PFOS), which have been detected and reported in fish, soil, and water samples. Other factors, such as rainfall, runoff, and sea-level oscillation, cause the water table in the Agana Swamp to fluctuate rapidly. Additionally, this region's surface water, underlain by limestone, actively interacts with groundwater. Several production wells for drinking water supplies are located in this region; thus, the Agana swamp's water quality can directly affect drinking water quality. Several technical reports have been published for the Agana Swamp since 1970, but most studies focused on a hydrological and geological survey. Regular water quality monitoring is essential to evaluate risk assessment, but no water quality baseline has been formulated/studied. To establish the baseline water quality of the Agana swamp, we will select three or four water sampling sites. For one year, basic water quality parameters will be monitored monthly; these include temperature, pH, dissolved oxygen, total-nitrogen, total phosphorus, nitrate, nitrite, ammonia, ortho-phosphate, total dissolved solids, and conductivity.