In recent years, wetlands have received increasing attention in environmental engineering. Both natural and constructed wetland systems are now being used to treat a wide range of industrial, urban, and agricultural effluents. In the present study, we measured the heavy metal uptake of a wetland area in Brazil that receives runoff water from runways and paved areas. We analyzed the water, sediments, and emergent macrophytes and compared the data with the results of other studies of the retention of pollutants by wetlands. We also determined the heavy metal accumulation by the dominant macrophyte using transfer coefficients to determine metal transfer among sediments, roots, and leaves. We found that although the wetland removed significant amounts of pollutants from the airport’s drainage water through sedimentation, precipitation, and uptake by plants, additional work must be done to increase water retention times in the wetland to improve the wetland’s ability to immobilize pollutants.