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Four alternative sewage disposal systems were evaluated to determine their ability to reduce nitrogen. The systems monitored in this study were: a shallow pressurized trench system, an intermittent sand filter followed by drip irrigation, a pressurized sandlined bed, and a proprietary aerobic treatment unit (Multi-flo). Systems were monitored pre and post treatment unit and from suction lysimeters and piezometers placed hydraulically upgradient and downgradient to the disposal component. The overall goal of the study was to measure the decrease in total nitrogen (TN) concentration in the waste stream caused by 1) the treatment unit, 2) plant uptake in the drainfield, and 3) dilution by ground water. Nitrogen reduction from the treatment units was less than 50% in all cases. Downgradient soil water samples had TN concentration 50% less than was measured in the dosing chamber. Results were not sufficient to differentiate the relative contribution from plant uptake vs. dilution for the decreased TN concentration. Overall, the intermittent sand filter system reduced TN concentration the most, and was the most consistent system for nitrogen reduction.