In a presedimentation impoundment, which option would most directly limit algae growth by reducing light exposure?

In a presedimentation impoundment, which option would most directly limit algae growth by reducing light exposure?

• A. Line the bottom
• B. Chlorinate to kill algae
• C. Use potassium permanganate
• D. Cover the impoundment

Answer: (D)

Algae need light to photosynthesize, so reducing light directly limits their growth. Covering the impoundment blocks sunlight from reaching the water, preventing photosynthesis and thereby limiting algae formation. The other approaches don’t address light exposure as directly. Lining the bottom may alter bottom conditions but won’t stop light from reaching the water surface. Chlorinating or using potassium permanganate kills algae chemically, but light exposure remains unchanged, so algae could regrow once treatment stops.

Algae need light to photosynthesize, so reducing light directly limits their growth. Covering the impoundment blocks sunlight from reaching the water, preventing photosynthesis and thereby limiting algae formation.

The other approaches don’t address light exposure as directly. Lining the bottom may alter bottom conditions but won’t stop light from reaching the water surface. Chlorinating or using potassium permanganate kills algae chemically, but light exposure remains unchanged, so algae could regrow once treatment stops.