Biofilters are underground structures located in remote areas. Their purpose is to remove Nitrogen(N) and Phosphate(P) nutrients from runoff, therefore reducing the number of pollutants being discharged to the environment. The most common forms of biofiltration include biological or natural systems such as riverbank filtration or soil aquifer treatment, and engineered filtration such as rapid sand filters, or chemical filtration. These designs are successful in N and P removal, however, they have several disadvantages, such as the down time required for cleaning them. Consequently, the utilization of engineered 3D printed biofilters is being developed and tested for its many benefits. These benefits include a high surface area which promotes the growth of microalgae which enhances N and P removal from runoff as well as more space for bacteria that form biofilm to grow. Lastly, it is a cheaper medium to manufacture and easier to clean.
