On Site Sewage Facilities (OSSF)

​​​​​​​​​​​​ To determine if the on-site sewage facility on your property is due for an inspection, view the report below:

For the rules and regulations pertaining to on-site sewage facilities, please review the court order provided below:

​OSSF Permits and Documents

  
  
collapse DocType : Form ‎(3)
OSSF_Certification.pdfAffidavit of OSSF Requiring Maintenance
ETJPlattingVerificationForm.aspxETJ Platting Verification Form
OSSF_Aerobic_Systems_Information_Sheet.pdfOSSF Information Sheet
collapse DocType : Document ‎(9)
Aerobic_Systems_Information_Sheet.pdfAerobic Systems Information Sheet
ESC-015_Septic_Maintenance.pdfMaintain your septic system to protect well water
On-Site Sewage Facilities Rules and Regulations (CO. No. 2008-187-03-11).pdfOn-Site Sewage Facilities Rules and Regulations (CO. No. 2008-187-03-11)
OSSF_Inspection_List.pdfOSSF Inspection Handout
StormWaterBrochure.pdfPreventing Stormwater Pollution at Construction Sites Brochure
Site_Evaluator_Info_Sheet.pdfSite Evaluator Information Sheet
constructionguide_final.pdfTCEQ Construction General Permit Requirements Brochure
DirtyDozen.pdfThe Dirty Dozen: 12 Tips to Prevent Storm Water Pollution Brochure
Driveway_TXDOT.pdfTxDOT Driveway Permit Information Sheet

OSSF FAQs

On Site Sewage Facilities (AKA "Septic")

  
Do I need to apply for OSSF (On-Site Sewage Facility) through Collin County?
• If your property is located OUTSIDE of city limits – you are required to apply for an OSSF permit through the Collin County Citizen Self-Service Portal. You can find instructions on how to use the portal, as well as other helpful information, Here.

IF YOU ARE BUILDING A NEW STRUCTURE THAT WILL CONNECT TO A NEW OSSF, THEN APPLY FOR YOUR DEVELOPMENT PERMIT FIRST AND STAFF WILL THEN SEND AN ASSOCIATED OSSF PERMIT THROUGH YOUR PORTAL TO BE COMPLETED BY YOU. DO NOT APPLY FOR A SEPARATE DEVELOPMENT PERMIT AND OSSF PERMIT.

• If your property is located INSIDE of city limits – you MAY BE required to apply for an OSSF permit through the Collin County Citizen Self-Service Portal. The Texas Commission on Environmental Quality (TCEQ) maintains a List of the permitting agency (Authorized Agent) for each city. First select “Collin” from the dropdown County list. If your city is not listed, Collin County is your Authorized Agent.
If Collin County is your permitting authority and you are adding a new structure, altering an existing structure or building a swimming pool on a property with an existing OSSF, you are required to apply for a Review of Existing OSSF for New Construction/Improvement permit through the Collin County Citizen Self-Service Portal.

Where do I find a Registered Sanitarian or Professional Engineer to design a new OSSF or design a repair to an existing OSSF?
Collin County maintains a courtesy List of local individuals that have the approved, required credentials to perform OSSF design work in Collin County. The list is provided solely for your convenience. Collin County in no way recommends or guarantees the work of any of the individuals on the list. You may choose any currently licensed Registered Sanitarian or Professional Engineer to perform your work.
Where do I find an Installer or Maintenance Provider for my OSSF?
The Texas Commission on Environmental Quality (TCEQ) maintains a List of certified/licensed providers.
What rules do I have to follow for OSSF?
In addition to the State Rules (scroll down and choose Chapter 285) for OSSFs, Collin County has a Court Order that details additional, more stringent rules that must be followed.
Where do I file the OSSF Affidavit?
The Affidavit must be filed with the County Clerk's Office located at 2300 Bloomdale Rd., Suite 2104, McKinney, TX.
Does my OSSF permit have an expiration date?
OSSF permits expire after 365 days of no activity (from date of issuance).
I have purchased a property that has an aerobic OSSF system.  How do I register the OSSF in my name?
Collin County requires three (3) forms when property is sold that has aerobic system: (1) Change of Ownership (2) Aerobic Wastewater Homeowner's Information sheet, and (3) Maintenance contract in new owner's name (must be obtained from your licensed maintenance provider).
Where do I send OSSF Contracts, Maintenance Reports or Change of Ownership Forms?
You can either mail them to: 4690 Community Ave., Suite 200 McKinney, TX 75071, fax to (972) 548-5555 or by email.
What is the minimum lot size to utilize an OSSF on a property?
Any lot divided between 1983 and 2008 (contact development services if exact dates in 1983 or 2008 are critical to your project) must start with a minimum of 1 acre (or 1.5 acres if there is a water well on the property) and any lot divided in 2008 or later must start with 1 useable acre (1.5 acres minimum with 1 acre useable if there is a water well on the property). “Useable” means useable for OSSF components/disposal area (excluding most easements, ponds, etc.).
What if my lot is smaller than required for OSSF?
If the small lot existed as that same small lot prior to 1983 (you will have to do your own research to find proof that the lot existed prior to 1983 and present that proof to Development Services) and if the designed/installed OSSF complies with all requirements set forth the State and County OSSF regulations, then it is allowed. Whether or not an OSSF can be designed and installed, meeting all current State and County OSSF regulations, for that specific lot cannot be determined until you hire a 3rd party Registered Sanitarian or Professional Engineer to evaluate the site and design a system.

If the property was made smaller than the required acreage after the aforementioned dates, the property is ineligible for an OSSF. PLEASE NOTE THAT PROPERTIES AFFECTED BY A GOVERNMENT TAKING (FOR A ROADWAY, ETC.) MAY STILL BE ELIGIBLE FOR AN OSSF. CONTACT DEVELOPMENTSERVICES@CO.COLLIN.TX.US WITH PROOF OF THE GOVERNMENT TAKING FOR REVIEW.