Water Treatment Wastewater Disposal


                                                                                                 Water Treatment Wastewater 
 16.1 General Standards 
  All WTW disposal systems shall prevent the discharge of WTW to the ground surface, wetlands, or open 
 watercourse, and shall comply with PHC section 19-13-B103g and the requirements outlined in the following 
 subsection (section 16.2). The DOH may require an inspection of the WTW disposal system. In areas where well 
 water treatment is anticipated, plans for new SSDSs shall designate an area where a WTW dispersal system may
 be installed in accordance with Table 9. WTWs approved by the commissioner to discharge to a SSDS are listed in Appendix D. 16.2 WTW Requirements.

1. Certain water treatment systems, including but not limited to, whole house or building reverse osmosis systems, may produce very large quantities of WTW that may require significant area for a WTW dispersal system, and in these cases the DOH may choose to require a PHC 19-13-B100a(e) review, pursuant to PHC 19-13-B103g(e), to ensure preservation of SSDS areas.

2. WTW solid conveyance piping shall have a minimum separating distance of 25 feet, 75 feet, and 100 feet, respectively, to public and private water supply wells with required withdrawal rates of <10 GPM, 10 to 50 GPM, and >50 GPM. The DOH may further reduce the distance to not less than 10 feet to private wells on existing developed properties if compliance cannot be met due to site limitations. WTW solid conveyance pipe shall be approved by the DOH and protected from freezing. Solid pipe listed in Table 2-A is acceptable for gravity WTW conveyance pipe, and pipe listed in Table 2-B is acceptable for pressure WTW conveyance pipe.

3. Non-discharging WTW disposal system components, including but not limited to, WTW holding tanks, WTW dispersal system settling or filtration structures, shall meet the minimum separation distances cited in Table 9, unless otherwise authorized by the Commissioner in the commissioner’s approval of the relevant WTW treatment or technology pursuant to PHC 19-13-B103g(b).

4. WTW dispersal systems shall meet the separation distances cited in Table 1, Item Q, and WTW dispersal system receiving structures shall meet the minimum separation distances cited in Table 9. Air gaps and breaks in WTW conveyance pipes that are outside of the building foundation shall meet the minimum separation distances cited in Table 9, unless otherwise authorized by the Commissioner, in the commissioner’s approval of the relevant WTW treatment or technology pursuant to PHC 19-13-B103g(b).

5. WTW holding tanks, including piping, shall be located at least 10 feet from SSDSs.

6. WTW dispersal systems and WTW holding tanks shall be H-20 load rated in vehicular travel areas.

7. The bottom of the WTW dispersal system shall be located a minimum 12 inches above maximum groundwater and 24 inches above ledge rock.

8. WTW dispersal systems shall have a minimum storage volume of 1.5 times of either the anticipated discharge per cycle or daily average, whichever is greater.

9. Stone aggregate used shall be free of silt, dirt and debris and covered with approved filter fabric.

10. WTW holding tanks shall provide an access cleanout to grade and be equipped with a high-level alarm.

11. The DOH or registered environmental health specialist licensed pursuant to Chapter 395 may approve the design of a WTW dispersal system or WTW holding tank prior to installation. Approval is not required from the Commissioner for WTW holding tanks; however, approval from the Commissioner is required for any sewage holding tank to receive WTW discharges. (See section 17.7).

12. The installer shall provide 24-hour minimum notice to the DOH prior to commencement of installation, unless otherwise approved by the DOH as part of the DOH approval of the WTW system.

13. An as-built drawing shall be submitted to the DOH that includes distances from 2 or more permanent reference points to the WTW disposal system.  

 Table 9. Water Treatment Wastewater Dispersal System Separation Distance Requirements 
Item Separation Distance (Feet) Special Provisions
Public or private water supply well with 
required withdrawal rate of: 
< 10 GPM 
10 – 50 GPM 
> 50 GPM 


75
150
200
The DOH may allow certain 
separation distance reductions 
on existing developed 
properties if compliance 
cannot be met due to site 
limitations. (1)(2)(3) 
Open Water Course 25
Public Water Supply Reservoir 100
Building 5
Property Line 10
Subsurface Sewage Disposal System See Table 1, Item Q
(1) Reductions shall not be granted to public water supply reservoirs or public water supply wells. 
(2) Reductions to private wells shall not be reduced to less than 25 feet. WTW discharges less than 75 
feet up-gradient of a private well shall be avoided, whenever possible. 
(3) The DOH shall not allow reduced setback distances if there is a concern that the WTW may negatively 
impact the quality of the groundwater.