On-Site Sewage Facility (OSSF) Regulation & Inspection

OSSF Regulations

The WCCHD Environmental Health Services is the authorized agent of the Texas Commission on Environmental Quality (TCEQ) for Williamson County. Each new or altered single family dwelling, multi-family dwelling, business, commercial, or industrial structure must be connected to an approved On-Site Sewage Facility (OSSF), or be connected to an authorized wastewater disposal system.

The Environmental Health Services staff faces unique challenges in the management of OSSF's in Williamson County because the soils are not generally appropriate for small lot conventional septic systems. Also, a significant part of Williamson County is in the Edwards Aquifer recharge or contributing zone.

The Williamson County Board of Health, in acknowledgement of these technical facts and the unprecedented rapid residential and commercial growth in the county, adopted in 1999 more restrictive OSSF regulations to better protect human health and the environment. Among the revised regulations for Williamson County was the requirement of one acre or more to install an OSSF. The WCCHD On-Site Sewage Facility Rules for Williamson County contains the full text of the regulations. The State regulations 30 TAC 285 State OSSF Regulations, can be viewed at the TCEQ website.

Inspection of a New OSSF
Environmental Health Services issues permits for OSSF's, commonly known as septic systems. Staff inspect the OSSF at various points during the critical phases of construction. A final inspection must be passed before the system can be used.

For more information about the OSSF inspection process call our office at (512) 943-3620. See also related OSSF fees.

How To Apply for a Permit
To begin the application process, the property owner needs to provide the deed and the survey of the property and be prepared to pay a permit fee (check or cash only). If the property is in an established subdivision, the survey is not required. If the property owner wishes to have their agent apply for the permit they must provide a notarized "power of attorney" note authorizing this person. The property owner will then be given specific instructions on how to obtain a soil report and how to choose a licensed installer and designer.

For more information about the OSSF permit process call our office at (512) 943-3620. See also related OSSF fees.

Re-Inspection of an OSSF
Most mortgage lenders require a re-inspection of an OSSF whenever the property is sold. Environmental Health Services staff perform a surface inspection for this purpose. The Application for Evaluation of an Existing On-Site Sewage Facility form describes the scope and limitations of this inspection.

For more information about OSSF re-inspection call our office at (512) 943-3620. See also related OSSF fees.

Additional Information

All OSSF forms, permits, fees, guides, and applications are available in our Forms Library.

These websites and additional documents provide more information about On-Site Sewage Facility regulation and inspection.

Advice for an Owner of an On-Site Sewage Facility
TCEQ: On-Site Sewage Facilities (Septic Systems)