Septic system requirements in Decatur County, Iowa
The septic rules landplan.io applies in Decatur County, what a septic tank costs there, and the parcel data we hold.
Updated
Design a septic system for an address in Decatur County
Iowa's state rules apply in Decatur County: landplan.io has no county rules of its own here. State rules: Reviewed See Iowa's rules
Septic systems allowed in Decatur County
The system types landplan.io permits in Decatur County:
- Mounded Leaching System
- Spray Distribution System
- Low Pressure Pipe System
- Drip Distribution System
- Leaching Trench System
- Infiltrator Advanced Treatment Leachfield (ATL)
- Infiltrator Advanced Enviro-Septic® (AES)
- Discharging System
Septic tank size in Decatur County
The daily design flow of a home: 150 gal/day per bedroom, at least 240 gal/day. The septic tank is sized from that flow:
| Daily design flow | Minimum tank |
|---|---|
| up to 240 gal/day | 1,000 gallons |
| 240 to 360 gal/day | 1,500 gallons |
| 360 to 600 gal/day | 2,000 gallons |
| 600 to 720 gal/day | 2,500 gallons |
| 720 to 840 gal/day | 2,750 gallons |
| 840 to 920 gal/day | 3,000 gallons |
| 920 to 1,040 gal/day | 3,250 gallons |
Septic setbacks in Decatur County
| From | To | Distance |
|---|---|---|
| Polygon | Existing Septic Component to be Abandoned | 5 ft |
These are the values the landplan.io design engine applies in Decatur County. Confirm a design with the Iowa health department or your county's before you build.
Parcel data in Decatur County
landplan.io has parcel boundaries for Decatur County (100% of its area): type an address and the design starts from the parcel.
Septic companies, designers and jobs in Iowa
Where the rules come from
The regulations and documents landplan.io's Decatur County, Iowa rules are read from:
- Private Sewage Disposal Systems (Iowa Admin. Code r. 567 Chapter 69)
- Iowa DNR Onsite News - Chapter 69 Legislative Session Delay (guidance on which separation distances apply) (Iowa DNR Onsite News bulletin (GovDelivery IACIO 3f26912))
- Story County Ordinance No. 287 - Chapter 65, Private Sewage Disposal Systems (signed ordinance) (Story County, Iowa, Code of Ordinances ch. 65 (Ordinance No. 287))
- Iowa DNR copy of 567 IAC 60.2(2)"c" Table I - Wastewater Separation Distances (from ch. 60, effective 6/18/2025) (Iowa Admin. Code r. 567-60.2(2)"c", Table I (DNR copy))
- Chapter 60 - Scope of Title, Definitions, Forms, Rules of Practice (Table I: Wastewater Separation Distances, 567-60.2(2)"c") (Iowa Admin. Code r. 567-60)
Near Decatur County
- Clarke County
- Ringgold County
- Wayne County
- Union County
- Lucas County
- Madison County
- Warren County
- Taylor County
- All of Iowa
Questions
What septic systems are allowed in Decatur County?
landplan.io designs by Iowa's state rules there and permits: Mounded Leaching System, Spray Distribution System, Low Pressure Pipe System, Drip Distribution System, Leaching Trench System, Infiltrator Advanced Treatment Leachfield (ATL), Infiltrator Advanced Enviro-Septic® (AES) and Discharging System.
What size septic tank do I need in Decatur County?
landplan.io sizes the septic tank in Decatur County from the daily design flow: up to 240 gal/day: 1,000 gallons; 240 to 360 gal/day: 1,500 gallons; 360 to 600 gal/day: 2,000 gallons; larger flows need larger tanks. A home's design flow is 150 gal/day per bedroom, at least 240 gal/day.
Does landplan.io have parcel data for Decatur County, Iowa?
Yes: parcel boundaries cover Decatur County (100% of its area).