APPENDIX D: MINIMUM SETBACK DISTANCES
Minimum Setback Distances of Components of OWTS to Site Features
 
Component Part of System
Distance (in feet) From:
Building Sewer, Force Main, or effluent conveyance pipe from pretreatment tanks to soil absorption component
Septic Tank, Holding Tank, Aerobic Treatment Unit, Media Filter, Lift Station, Grease Interceptor
Primary and Reserve Soil treatment Area (basal area, mantle, edge of in-ground trench/bed, drip tubing, constructed wetland)
Large Capacity Septic System5
Wells1 or Suction Lines
502
50
75
200
Water Supply Line Under Pressure, In-ground swimming (water edge)
10
10
25
25
Above Ground Swimming Pool, hot tub, lined decorative pond
5
5
10
10
Surface Waters, Retention Facility (ordinary high water mark)
25
25
25
25
Wetlands
10
25
25
25
Detention Facility High Water Line
10
10
25
25
Building with Foundation Footing Drain
NA
10
203
10
Building Without Foundation Footing Drain
NA
5
10
10
Property Line, Fence Posts, Structure Support Posts
3
3
5
5
Driveways, Patios, Sidewalks, Retaining Walls
NA
5
104
104
Agricultural Drain Tile, Perforated Pipe
10
10
10
10
Drainage Easement, Open Ditches, Road Cuts, Storm Sewer Pipe
5
5
5
10
Utility Easements
5
5
5
5
Sealed Well
5
10
25
25
Upslope or Sideslope of Soil Treatment Area for System Types III, IV and V, Soil Treatment Area for All Other System Types
NA
5
NA
NA
Clearwater Conveyance Pipe
NA
5
10
10
Downslope of Soil Treatment Area for System Types III, IV and V
NA
10
NA
NA
Footnotes:
1- For separation distances to closed loop wells see 77 111. Adm. Code 920.180
2- A building sewer may be located to within 10 feet of a well or suction line from the pump to the well when cast iron pipe with mechanical joints or Schedule 40 PVC pipe with watertight joints is used for the building sewer. A force main may be located to within 10 feet of a well or suction line from the pump to the well when Schedule 40 PVC pipe with watertight joints is used.
3- The distance to the upslope edge of the basal area of a Type 3, 4 and 5 system can be reduced by 50% on sites where the soil treatment area is on a slope of 2% or greater.
4- This distance can be reduced by 50% if the soil treatment area is the edge of a trench/bed (System Type 1 or 2), drip tubing, or upslope or sideslope side of a soil treatment area.
5- Large Capacity Septic Systems, which are classified as Class V Injection Wells, are described and defined in the Illinois Pollution Control Board rules. They are typically a shallow well used to place fluids below the land surface. See 35111. Adm. Code 704.105, 704.106 and 704.280.
(Ord. [Bd of Health Ord., Art. V], passed 11-12-1996; Ord. [Bd of Health Ord., Art. V], passed 11-12-2013; Ord. 17-0605, passed 6-13-2017; Ord. 19-0775, passed 5-14-2019)