Potential Replacement of Septic Tank Drain Fields by Artificial Marsh Wastewater Treatment Systems

Use of emergent marsh vegetation planted in a gravel substrate in a plastic-lined trench to treat septic tank effluent is demonstrated. Treatment of unchlorinated primary municipal effluent reduces BOD 5 by 77%, COD by 71%, orthophosphate by 35%, total phosphorus by 37%, nitrate by 22%, and coliform bacteria by 99.9%. The method is useful at summer cottages, camping areas, resorts, and roadside rest areas. Marsh treatment systems are inexpensive to operate and virtually automatic.