What is the minimum detention time required for flocculation facilities for basins built after October 1, 2000?

The correct response highlights that a minimum detention time of 2 minutes at design capacity is mandated for flocculation facilities in basins constructed after October 1, 2000. This requirement is based on the need for adequate contact time to ensure effective floc formation and settling of particles within the water treatment process.

Flocculation is a critical step in water treatment, where finely divided particles agglomerate into larger clusters or "flocs" that can then be removed from the water. By specifying a minimum detention time of 2 minutes, regulations ensure that there is sufficient time for flocs to form and grow to a size that allows for efficient sedimentation or removal, thereby enhancing the overall effectiveness of the water treatment process.

Understanding this requirement is essential for maintaining compliance with water quality standards and ensuring that treatment facilities operate efficiently. An adequate flocculation time is crucial in ensuring that contaminants are properly removed, thereby safeguarding public health and the environment.