Protecting Public Health and the Environment.

Technical Guidance Manual for Individual and Subsurface Sewage Disposal Systems

This document provides guidance on the design, construction, alteration, repair, operation, and maintenance of standard individual and subsurface sewage systems, their components, and alternatives. The manual is updated periodically to adapt to the dynamic and complex nature of small wastewater disposal systems; updates are cited below.

Current Year's Updates to the Manual

2020
Description
May
Section 1.5.1 Installer’s Registration Permit and Service Provider Certification Application, Bond, Fee, Training, and Exam (pp. 1-10 to 1-11)
Section 4.19.3.2 Pressurization Unit (pp. 4-95 to 4-96)
August
Section 4.3.3 Above-Grade Capping Fill System (p. 4-19)

Previous Years' Updates to the Manual

2019
Description
December
Section 1.4.2.1.1 Initial Septic Tank Approvals (p. 1-4)
Section 3.2.3 Septic Tank and Dosing Chamber Installation (p. 3-6)
Section 5.8 Septic Tank Effluent Filters, Table 5-12 (p. 5-23)
October
Section 4.23.3.2.1 Standard Enveloped In-Trench Filter Design and Construction. Figure 4-39. (p. 4-136)
Section 4.23.3.2.2. Pretreated Enveloped In-Trench Sand Filter Design and Construction. Figure 4-40. (p. 4-137)
Section 4.23.3.2.3. Pressurized Enveloped In-Trench Sand Filter Design and Construction. Figure 4.41. (p. 4-138)
Section 5.2. Approved Septic Tanks. Table 5-1. (p. 5-2)
Section 5.11. Drainfield Remediation Components. Table 5-15. (p. 5-27)
Section 5.13. Proprietary Wastewater Treatment Products. Table 5-17. (pp.5-29–5-30)

July
Section 2.2.5. Method of 72 to Determine Effective Soil Depths (pp. 5-17 to 5-19)
Section 4.23. In-Trench Sand Filter (pp. 4-133 to 4-138)
Section 5.2. Approved Septic Tanks, Table 5-1 (pp. 5-2 to 5-11)
Section 5.4. Extended Treatment Package Systems, Table 5-3 (pp. 5-13 to 5-15
Section 5.5. Approved Nondischarging Products, Table 5-5 (p. 5-17)

March
Section 1.9.5. Property Owner Operation, Maintenance, or Monitoring Requirements (pp. 1-31 and 1-32)
Section 4.24.3.1. Sand Mound Absorption Bed Cell Design (p. 4-141)
Section 5.2. Approved Septic Tanks, Table 5-1 (pp. 5-2 to 5-10)
Section 5.5. Approved Nondischarging Products, Tables 5-5 to 5-8 (pp. 5-17 to 5-19)
Section 5.13. Proprietary Wastewater Treatment Products, Table 5-13 (pp. 5-29 and 5-30)
January
Section 5.14. Updated products list in Table 5-15 (pp. 5-29 to 5-30)

Technical Guidance Committee

Next Scheduled Meeting Date

Thursday, November 5, 2020, 9:30 a.m. to 3 p.m.
DEQ State Office, Conference Room C
Agenda and Appendices TBD
This meeting will accommodate remote participants via telephone and web conferencing.
Remote participants may join the CenturyLink conference call from their phone:
Call-in phone number: (877) 820-7831    Call-in password: 903260
Remote participants may also join the Zoom web conference to view the shared documents.  No webcam or microphone necessary.
For more information or the Zoom login ID and password, please contact Peter Adams at Peter.Adams@deq.idaho.gov 

 

Meeting Minutes

For previous meeting minutes, contact the On-Site Wastewater Coordinator.

 


Page Subscription

Staff Contacts

On-Site Wastewater Analyst
Peter Adams
DEQ State Office
Water Quality Division
1410 N. Hilton
Boise, ID 83706
(208) 373-0464
Peter.Adams@deq.idaho.gov

Health District Contacts

For questions regarding a proposed or existing on-site wastewater system permit or inspection, please contact your local public health district.

DEQ Resources

More Information

Individual/Subsurface Sewage Disposal Rules

Idaho Code Related to Individual and Subsurface Sewage Disposal Systems

Rules Governing the Cleaning of Septic Tanks

Related Pages

On-Site Wastewater Systems (Septic Systems)

Extended Treatment Package Systems (Aerobic Treatment Units)

For Engineers and Developers