77 Ill. Adm. Code 905.160
Swimming Pool Wastewater
Section 905
Section 905.160Â Swimming
Pool Wastewater
a)        General. Wastewater generated from the operation of a
swimming pool includes clear wastes, such as drainage from the pool proper,
deck drainage, and perimeter overflow system drainage, and turbid wastes, such
as filter wash and backwash water.
b)        Approved Treatment and Disposal. Wastewater from swimming
pools may not be discharged to a private sewage disposal system receiving
domestic sewage. It shall be disposed of in the following manner:
1)Â Â Â Â Â Â Â Â Clear water wastes may be discharged directly to storm sewers,
natural drainage areas, or to the ground surface without additional treatment.Â
Such drainage shall not result in nuisance conditions which create an offensive
odor, or which produce a stagnant wet area, or which produce an environment for
the breeding of insects. These discharges will require an NPDES Permit from
IEPA if contaminants are added to the discharge that will cause any water
quality violation.
2)Â Â Â Â Â Â Â Â Wash or backwash water from sand filters may be discharged to
natural drainage areas, storm sewers, seepage pits, or to the ground surface.
Diatomaceous earth filter wash or backwash water may be discharged to one of
the above after treatment consisting of one of the following:
A)Â Â Â Â Â Â Â Passing the wastewater through a separation tank designed for removal
of the diatomaceous earth and suspended solids.
B)Â Â Â Â Â Â Â Settling the wastewater in a tank which is capable of holding
the volume of one backwash. One backwash is defined as the amount of water
generated from the backwash of the filters for a period of 2 minutes for
diatomaceous earth filters, at the required backwash flow rate. The tank shall
be dewatered after settling and prior to subsequent backwashes. Settled sludge
shall be periodically removed to prevent flushing of solids during
backwashing. (See Appendix A: Illustration W of this Part.)
C)Â Â Â Â Â Â Â A separate private sewage disposal system designed and
constructed in accordance with the applicable Sections of this Part.