Ten States Standards for Clarifier Weirs
Weir overflow rate is critical to prevent high-velocity approach currents that pull settling floc or solids over the effluent launders.
- Plants ≤ 1.0 MGD: Standard maximum WOR is 10,000 gpd/ft.
- Plants > 1.0 MGD: Standard maximum WOR is 15,000 to 20,000 gpd/ft.
- Clarifier Surface Loading Rate: Typically 500 to 1,200 gpd/sq ft.