The municipal solid waste (MSW) dump in Boragaon, Guwahati, lies on the fringe areas of the wetland, Deepor Beel, which is a Ramsar site. The study was undertaken to analyze the impact the solid waste dump has on the adjoining wetland. Five sampling locations (S1, S2, S3, S4 and S5) in the wetland were selected within a distance of 3000 m from the MSW dump for the continuous monitoring of the surface water and sediment of the wetland. Nineteen physicochemical parameters (pH, EC, air and water temperature, total hardness, alkalinity, turbidity, DO, free CO₂, TDS, BOD, Na⁺, K⁺, Ca²⁺, Cl⁻, NO₃⁻, HCO₃⁻, PO₄³⁻, SO₄²⁻) were analysed in the surface water, and 7 physicochemical parameters (pH, EC, %OC, %N, PO₄³⁻, K⁺, Na⁺) were analysed in sediment. Heavy metals Cu, Ni, Cd, Cr, Mn, Zn and As were analysed in surface water and sediment samples. The results of the principal component analysis (PCA) and cluster analysis (CA) applied on the surface water data have aptly described the source of contamination in the study area to be from the adjoining MSW dump site. The surface spread of contamination from the MSW dump towards the wetland was evident from the regression equations drawn from the sediment data. The mean concentration of Mn, Cr, Ni, Cd and As in surface water exceeded the MPL (maximum permissible limit) of WHO 2011 (World Health Organization). The pollution load index (PLI) of sediment in the wetland shows that the study area is under the category of “progressive deterioration”.