Why are water intakes positioned at different levels in a lake?

Water intakes are strategically positioned at different levels in a lake primarily to find the cleanest water during seasonal turnover. During this natural phenomenon, water layers in the lake mix due to changes in temperature, density, and wind effects. As a result, the bottom layers may contain sediment and decay while the upper layers can provide fresher, clearer water. By having intakes at various depths, operators can draw from the layers that are less impacted by these factors, ensuring a higher quality of water for treatment and distribution.

The other aspects consider factors such as temperature variations and access during low water levels, but they do not address the primary concern of maintaining water quality effectively during seasonal changes. Aesthetics, although potentially relevant, are not a guiding factor in designing water intake systems focused on quality and safety.