Slide 49 of 119
Notes:
In this design, runoff flows through a rock filter with wetland plants at the surface. Pollutants are removed through biological activity on the surface of the rocks, as well as by pollutant uptake of the plants. This practice is fundamentally different from other wetland designs because, while most wetland designs behave like ponds with differences in grading and landscaping, gravel-based wetlands are more similar to a filtering system. This treatment practice was adapted from wastewater treatment applications, and relies on anaerobic reactions for greater nutrient removal.