Rills and gullies interfere with revegetation and maintenance, such as mowing on highway embankments. Large amounts of sediment leaving an eroding site fill downstream water-conveyance channels and reservoirs. Fine sediment degrades water and air quality.
Before conservation planning can occur, a criterion for excessive erosion is chosen as the basis for selecting conservation practices. One criterion is a performance-based standard where the erosion- and sediment- control practices must reduce erosion and sediment- delivery rates to less than the standard under site- specific conditions. The other criterion is based on the application of best management practices (BMPs) where particular practices are chosen without full consideration of the resulting erosion and sediment-delivery rates.