Student Research Reports

View Research Report

This study, titled "A Study of the Relationship Between Runoff Volume, Water Quality, and Saltwater Intrusion in the Bang Pakong River," aimed to investigate the relationships between runoff volume, water quality, and saltwater intrusion, as well as the relationship between distance from the river mouth and water quality parameters and saltwater intrusion. Data was collected from June to October. Runoff volume ranged from 102.745 to 550.07 million cubic meters, and average salinity ranged from 0.13 to 1.85 ppt. Runoff volume showed an inverse relationship with salinity, while TDS and electrical conductivity showed a direct relationship with salinity. This is because runoff dilutes salt and pushes back seawater intrusion. However, high tides in late October led to higher salinity. Dissolved oxygen (DO) levels ranged from 2.75 to 8.25 mg/L, exceeding standards at several points. No significant relationship was found between runoff volume, distance from the river mouth, and salinity, due to the influence of organic leaching and local activities. Nitrate levels were not detected at any point except point A in June, where levels exceeded the standard. While nitrite and ammonia levels remained within standard limits throughout the study, the temperature and pH also remained within standard limits at all points. Monthly CCME WQI values ranged from 85.32 to 95.32, classified as good to very good, primarily affected by DO levels below standard and nitrate levels exceeding standard in some areas. Furthermore, location-based comparisons revealed that salinity was highest near the river mouth and decreased with distance from the mouth. DO and CCME WOI values also varied with local activities. In conclusion, runoff volume and land location play significant roles in changes in salinity and water quality of the Bang Pakong River.