Adverse effects are long term, impairing the habitat long after the visual presence of the silt in the water is gone. Some of Maine's lakes have natural sand beaches. They were created over time by geology and water movement. Plants and animals have adapted to these environments, and the beach areas are stable. However, a load of sand dropped at the edge of a lake is a form of pollution and the combined effect of many beaches can harm the lake.
Sand can be a significant source of phosphorus, a nutrient that contributes to algal blooms.
Sand can also cover critical edge habitat, suffocating freshwater clams and mussels and eliminating fish breeding areas. An artificial beach rarely stays put. Water and waves wash away the sand. Without continual new additions of sand the beach will disappear. As more sand is added to replenish the beach, the sand gradually spreads out over the bottom of the lake, smothering more and more habitat.