Sediment trap efficiency of a small reservoir

The sediment trap efficiency of a 2.7-acre reservoir was measured during a 2-year period. While the overall trap efficiency was about 77%, monthly trap efficiencies ranged from 9% to 100%. Trap efficiency was generally much higher for storms accompanied by high sediment loads and high sediment concentrations. Trap efficiency was generally low for storms producing low sediment concentrations. Highly variable flow detention times may explain part of the variation in storm trap efficiencies.