Select Page

On-Site Sewage Facility (OSSF) – Frequently Asked Questions

On-Site Sewage Facility (OSSF)

Do I need to obtain a permit to build an On-Site Sewage Facility (OSSF)?

Yes, all new constructed and replacement On-Site Sewage Facilities (OSSF) will require a permit.

How do I apply for an On-Site Sewage Facility (OSSF) permit?

You can apply online via or using a paper application. The paper application can be found on the Hays County Development Services website or in person at the Development Services office.

How much does it cost to apply for my OSSF permit?

The type of system will determine the cost of the permit. You will need to contact a designer to see what the best system type for your property is. All our fees can be found on the Hays County Website (

How do I know what type of septic system to install at my home?

The type and size of the system will be determined by the licensed septic designer. The designer will take in consideration the size of the home and the amount of people who will be using the system.

Who should apply for the OSSF permit?

Anyone who is associated with the development / replacement of the OSSF can apply for the permit.

What documents do I need to submit when applying for a new system?

When you apply for your OSSF Permit, you will be required to submit a series of documents. These documents are: tax account summary, site plan, location map, floorplan of home/structure, septic design, OSSF affidavit (when applicable), and two-year initial contract from a maintenance provider (when applicable).

What type of OSSF requires a maintenance contract?

Any aerobic or advanced treatment systems, such as drip irrigation, will require a maintenance contract.

Why is a maintenance agreement required for an aerobic septic system?

A maintenance agreement is required for all aerobic onsite sewage facilities. Hays County requires ongoing maintenance with a Licensed Maintenance Provider. Having the maintenance agreement benefits you (the homeowner) by having a trained professional service and monitor your On-Site Sewage System for problems with the system before they result in a public health nuisance.

Can I install my own OSSF?

Yes. A homeowner can install their own residential On-Site Sewage System. Only a Licensed Installer can install a system that is used for commercial use, including rental houses.

Who do I contact about a complaint on a neighboring OSSF system?

 You can call the Hays County Development Services at 512.393.2150 and speak with an Environmental Health Specialist or email us at

Can a homeowner maintain their own / new OSSF?

Yes, but only after the initial two years after installation. All new On-Site Sewage System requires an initial 2 year contract with a licensed maintenance provider. After the initial two year contract expires, you can take a class in order to be certified in maintaining your own on-site sewage facility. There are several options for a homeowner to maintain their own system.

1. Texas A&M Agrilife Extension (TEEX) (

2. Basic Maintenance Course and Test from TOWA


3. Obtain a class D or higher wastewater operator’s license from the Texas Commission on Environmental

Quality (

Development Permits in
Hays County

Read through the Frequently Asked Questions to the left to learn more about the development permitting process for Hays County. If you cannot find an answer to your specific question, please contact our office via phone or email: 512.393.2150 or

Hays County