Pollution of surface and groundwater is a growing public and environmental concern. Many techniques are being developing to manage land application of manure, especially in land deficient areas. One development has been the use of overland flow-riparian buffer system that assist in removing nitorgen and phosphorus from the lquid manure, therefore increasing the amount of liquid prroduct/acre that can be applied.

The ovreland flow-riparian buffer consisted of a 4 m wide and 30 m long vegatative strip consisting of a 10 or 20 m grass buffer zone and a 10 or 20 m riparian buffer zone, postioned on the landscape acording to land contour. Surface and groundwater were sampled at the top and bottom of each plot, with ground water being measured at depths of 0.5, 1.0, 1.5 and 2.0m depths.

The surface runoff water quality showed a large decrease in the N concentration near the bottom of the plot, due to assimilation of N by grasses, trees and shrubs and losses through ammonia volatilization. Evaluation of shallow ground water showed a sunstantial reduction in NO3-N from the top to the bottom of each plot. Little difference was reported between the three type of vegative strips used, howver the plot containing a 20 m grass buffer was somewhat less efective in assimilating N relative to the other two plolts.