The study assessed the physicochemical characteristics, including pH, organic carbon, nitrogen, phosphorus, and the concentrations of heavy metals (Zn, Cr, Pb, Mn, Cu, Ni, and Cd) in the coastal lowland areas of Ernakulam district, Kerala. The findings indicate that the concentrations of heavy metals in the soil samples ranged as follows: chromium (Cr) from 0.073 to 0.311 mg/g, manganese (Mn) from 0.113 to 0.364 mg/g, nickel (Ni) from 0.017 to 0.065 mg/g, zinc (Zn) from 0.037 to 1.136 mg/g, cadmium (Cd) from 0.012 to 0.073 mg/g, copper (Cu) from 0.021 to 0.036 mg/g, and lead (Pb) from 0.039 to 0.053 mg/g. The concentration of heavy metals in soil samples was observed in the following descending order: Zn > Mn > Cr > Pb > Ni > Cd = Cu. Soil contamination was evaluated using the geo-accumulation index (Igeo), contamination factor (Cf), and Pollution Load Index (PLI). The average Igeo values were Cr-21.51, Mn-18.29, Ni-8.33, Zn-9.32, Cd-58.38, Cu-9.60, and Pb-6.87. Elevated Igeo values for Cd and Cr were noted at certain sampling stations. The PLI values for the sample stations (S1-S8) were 4.31, 3.60, 3.29, 4.21, 2.81, 2.32, 3.25, and 1.57, respectively. High contamination levels were observed for Cd and Cr at specific stations based on the Cf values. The spatial distribution of heavy metals was mapped using interpolation techniques. The results revealed that zones with high concentrations of Cd were located near industrial dumping areas. Conversely, the highest Pb, Mn, Cr, Ni, Cu, and Zn concentrations were found in the southeastern region adjacent to the effluent dumping zones. The ecological risk assessment indicated significant risks associated with these metals in sediment samples.