As water temperature decreases, what happens to settleability?

As water temperature decreases, settleability becomes slower due to the increased viscosity of the water. When temperatures drop, water molecules move more slowly, which affects the overall movement of particles suspended in the water. This results in reduced kinetic energy, making it more difficult for particles to overcome the forces keeping them in suspension and allowing them to settle at the bottom of a treatment vessel.

The slower settleability at lower temperatures can also be attributed to the reduced activity of microorganisms and the chemical processes involved in treatment processes, which may be less efficient in colder conditions. This phenomenon is particularly important in drinking water treatment processes, where optimal conditions for sedimentation and clarification are crucial for effective removal of solids and contaminants.