Removal of Nutrients and Other Pollutants from Agricultural Drainage Ditch Water

The purpose of this award is for the grantee to develop ditch water filter technology and implementation guidance for ditch drained agro-ecosystems.Agricultural drainage ditches, which are commonplace on Maryland’s eastern shore and lower Delaware, represent a major transport pathway for nutrients, sediments, and other potential contaminants to surface-water bodies. These ditches also represent a possible intervention point in the system at which P derived from runoff and sub-surface flow generated across large acreages of agricultural soils can be prevented from entering the Chesapeake Bay at a single point. We propose the use of a phosphorus sorbing material (PSM) filled structure placed within drainage ditches to act as a P “filter”. Such a P removal structure would allow the removal of P from the aquatic system when P saturated PSMs are removed from the structure. Field prototypes of the proposed system have shown a high likelihood of success, removing approximately 99% of the P from treated water. In addition to removing P from ditch water these treatment systems have the potential to remove nitrogen, sediment, and other contaminants.