Evaluation of agricultural best-management practices in the Conestoga River headwaters, Pennsylvania: A summary report, 1982-90

Pipe-outlet terracing was effective in reducing sediment losses from a field site, but total nitrogen and phosphorus losses with runoff were not significantly different before and after terracing. Median concentrations of dissolved nitrate in several ground-water sampling locations increased after terrace installation. Dissolved nitrate concentrations in ground water decreased significantly after nutrient-management implementation. Findings indicate that agricultural-management practices to improve water quality are most effective if their overall design effects on surface- and ground-water systems are considered in their design.