Wetlands are commonly understood to have the capacity to reduce the loads of excess nutrients, pathogens, sediments, and other contaminants generated by various activities in their catchment areas. However, quantifying these “services” is difficult and most research in this field has concentrated on artificial treatment wetlands. Understanding the value of their water treatment characteristics, as well as the other services they provide, is increasingly recognized as essential to achieving a balance between conservation and activities that degrade or replace wetlands.