The goal of the research was to estimate the amount of pollutants washed off from highways during rainfall. The researchers monitored five locations to measure the concentrations of pollutants like sediments, metals, and toxic chemicals in the runoff. They found that highways are highly polluted areas due to vehicle activities, with event mean concentrations ranging from 45.52-125.76 mg/L for TSS, 52.04-95.48 mg/L for COD, 1.77-4.48 mg/L for TN, and 0.29-0.54 mg/L for TP. This study provides valuable information on the pollution levels in highway runoff, which can help in managing and improving water quality in rivers.