Johnson County Septic System Permitting

The Wyoming Department of Envrionmental Quality delegated the authority and responsibility to enforce and administer the provisions of W.S. 35-11-304 for small wastewater treatment facilities to Johnson County.  

Septic Permits are required prior to construction of all small wastewater treatment facilities.  

Johnson County requires a registered licensed engineer design all septic systems.   A septic acknowledgement is required in addition to all design applications.  


For information on Permitting Requirements contact the
County Sanitarian at the:


Johnson County 
Planning Department
26 N DeSmet Ave
Buffalo, WY  82834

OR call 307-684-1907.


All applciations and forms shall be submitted to the Planning Department prior to issuance of a Septic Permit.


Downloadable FORMS:

Septic Acknowledgement

Septic Design Application

Percolation Test Procedures

Certificate of Completion 

A certificate of Completion is only required when inspection has not be completed.  Inspections are required to be arranged 24 hours prior to backfilling.



Septic Regulations:  

In July 2016, revisions to Chapter 25, Wyoming Department of Environmental Quality (DEQ) Water Quality Division (WQD) Rules and Regulations were signed into effect.  

Current Small Wastewater Facitility Regulations



Helpful Links:

FAQS - Coming Soon

Web Soil Survey


Wyoming Department of Environmental Quality; Water Quality Division

Approved Septic Tanks 

Chamber Equivalent Areas