Effectiveness of Agricultural Best Management Practices for Control of Nutrients in Runoff

Abstract Best management practices (BMPs) have been applied for erosion control and soil conservation worldwide for many years. BMPs have been expected to result in water quality improvements in rural areas in addition to functioning in soil and water conservation and erosion control capacities. In recent years, interest in control of nonpoint source (NPS) pollution from agricultural areas has resulted in studies of the effectiveness of BMPs for reduction of NPS pollution. In this paper, the physical characteristics and functions of several frequently applied BMPs are reviewed. The effectiveness of these BMPs in reducing nutrients in agricultural runoff is evaluated on the basis of available field studies. Combining several complimentary BMPs into a Best Management System (BMS) typically results in effective reduction of nutrients in run-off from agricultural areas. However, even with implementation of a well designed BMS, it may take more than 10 years to achieve measureable reductions in nutrient concentrations in receiving waters. Thus, BMPs and BMSs should not be considered a quick solution for water quality problems.