Wisconsin Administrative Code
Department of Natural Resources
NR 800 - Environmental Protection - Water Supply
Chapter NR 811 - Requirements For The Operation And Design Of Community Water Systems
Subchapter XII - Waste Disposal
Section NR 811.857 - Backwash wastewater from lime softening water treatment plants
Current through August 26, 2024
Filter backwash wastewater from lime softening water treatment plants shall be disposed of by any of the following methods:
(1) RECYCLE. Returned to the inlet end of the plant in accordance with the requirements of s. NR 811.862.
(2) DISCHARGE TO A SANITARY SEWER. Lime softening backwash water may be discharged to a sanitary sewer system subject to the requirements under s. NR 811.85 (1) (a).
(3) DISCHARGE TO A WATER OF THE STATE. Backwash wastewater from lime softening treatment plants may be discharged to a water of the state subject to the requirements under s. NR 811.85 (1) (b). Suspended solids shall be removed from the filter backwash wastewater prior to discharge by means of settling, and possibly coagulation. The pH shall be adjusted to within the range of 6.0 and 9.0 prior to surface water discharge.
