Verified against county records · sources last read August 31, 2026 · rules change — confirm with the agent before applying
A new single-family septic permit in Hays County costs $610 plus a $10 state fee, and the county requires one no matter how large your tract is. Before any of that matters, check one thing: four cities inside Hays County issue their own septic permits, and if your property sits in one of them, Hays County is not your permit office.
Hays County does not permit the whole county, and the map is not the one most people assume. TCEQ’s authorized-agent record for Hays County (AR 620098, status Current) states the county serves the “entire County except Cities of Dripping Springs, Niederwald, San Marcos, & Uhland.”
Those four cities are their own authorized agents. Everywhere else in Hays County, including inside city limits, the county takes the application.
That last point catches people out. Wimberley is incorporated and is still permitted by Hays County. The City of Wimberley says so on its own website: “On-site sewage facilities will now be permitted through Hays County.” So the common shorthand — that county septic permits cover “the unincorporated areas” — is wrong here, and the county’s own website summary repeats it. The Order is the better authority. Section 6.A says the rules apply “to all areas lying within Hays County, Texas, except for the areas regulated under an existing Order, Ordinance, or Resolution.”
If you are in Buda, Kyle or Woodcreek, you are on county septic rules. If you are in San Marcos, Dripping Springs, Niederwald or Uhland, stop reading and call the city.
Where the county’s office is:
| Office | Hays County Development Services |
| Address | 2171 Yarrington Rd, Suite 100, Kyle, TX 78640 |
| Phone | (512) 393-2150 |
| Contact of record | Eric Van Gaasbeek |
| Hours | Monday–Thursday 8am–5pm, Friday 8am–12pm |
| Applications | MyGovernmentOnline only, at MGOConnect.org |
Our directory of Texas septic permit authorities lists the agent for every county in the state.
This is the rule that decides whether you can build at all, and Hays sets it far above the state floor. Most Texas counties either take the state minimum or add a flat acreage number. Hays uses a matrix: your minimum lot size depends on which Edwards Aquifer zone you are in, where your water comes from, and whether the system is advanced or conventional.
Table 10-1 of the Hays County Order, in acres:
| Zone | Water supply | Advanced system | Conventional system |
|---|---|---|---|
| Recharge zone (EARZ) | Surface or rainwater | 1.50 | 2.00 |
| Recharge zone | Public groundwater | 2.50 | 4.50 |
| Recharge zone | Private well | 3.00 | 5.00 |
| Contributing zone (EACZ) | Surface or rainwater | 1.00 | 1.50 |
| Contributing zone | Public groundwater | 1.50 | 2.50 |
| Contributing zone | Private well | 2.00 | 3.00 |
| Elsewhere in county | Surface or rainwater | 0.50 | 1.00 |
| Elsewhere | Public groundwater | 1.00 | 1.50 |
| Elsewhere | Private well | 1.50 | 2.00 |
New subdivisions and manufactured-home rental communities on individual private wells inside the Priority Groundwater Management Area need 6.00 acres, whichever system type.
Two things fall out of that table. A conventional system on a private well in the recharge zone needs five acres; an advanced system on the same lot needs three. The zone does not dictate your system type in Hays — it prices it in acreage. And the state’s own recharge-zone floor of one acre, set by 30 TAC § 285.40(c)(1), is the smallest number anywhere in the county and applies nowhere on this table.
The Edwards rules add requirements the county does not set. On the recharge zone, § 285.40(b) requires that “All planning materials shall be submitted to the permitting authority by a professional engineer or professional sanitarian” — a licensed site evaluator alone is not enough. No sewage or holding tank may sit within 50 feet of a recharge feature, and no soil absorption system within 150 feet.
Hays names its creeks and rivers individually rather than relying on the state’s general water-body setback. For lots created after the Order took effect, effluent dispersal areas must sit 150 feet from Barton Creek, Bear Creek, the Blanco River, Cottonwood Creek, Cypress Creek, Little Bear Creek, Lone Man Creek, Long Branch, Onion Creek, Purgatory Creek, Roy Creek, the San Marcos River, Sink Creek, Smith Creek, Willow Creek and Wilson Creek, measured from the bank at average pool height.
Other distances from Table 10-2 and Section 10.F:
The fee schedule effective January 1, 2026 sets the single-family application at $610 and everything non-residential at $910, each carrying a separate $10 state fee.
| Fee | Amount |
|---|---|
| OSSF permit application, single family residence | $610 + $10 state fee |
| OSSF permit application, non-single family | $910 + $10 state fee |
| Minor system alteration | $310 + $10 state fee |
| Major system alteration | $510 + $10 state fee |
| Reinspection / tie-in inspection | $150 |
| Design resubmission | $150 |
| OSSF renewal | $600 single family, $900 non-single family |
| Maintenance contract late fee | $50 |
| Variance, Type I administrative | $100 |
| Variance, Type II Commissioners Court | $500 |
The schedule defines what it means by an alteration. Minor covers “sprayhead relocation, distribution line replacement, lift station addition, pump tank replacement.” Major covers “conversion from spray to drip, aerobic treatment unit replacement.” A renewal is only available with “a letter from designer stating no changes have/will be made to original design.”
The $10 is TCEQ’s, not the county’s. Order Section 12: “A fee of $10 will also be collected for each on-site sewage facility permit to be paid to the Texas Commission on Environmental Quality.”
One fee the county requires but does not publish. Order Section 10.K.1 requires annual registration to operate any surface-application system or any system carrying a maintenance contract, and says “The registration fee amount shall be in accordance with the current fee schedule adopted by Commissioners Court.” Neither the January 2026 schedule nor the older one it replaced contains that line. We are not going to guess at it. Call Development Services at (512) 393-2150 and ask what the annual registration costs before you budget the first year.
Two other things cost nothing, which is worth knowing because they look like they should. Maintenance provider registration is “free of charge” under Section 10.V.3. And there is no separate authorization-to-construct fee — the county issues that during technical review, inside the single application fee.
For how Hays compares across the state, see our Texas septic permit fee index.
Hays County has closed the state’s ten-acre exemption, in one sentence. Order Section 10.W.1:
“A permit will be required for all On-Site Sewage Facilities, regardless of the size of the lot or acreage onto which it is installed. A permit will not be issued for an On-Site Sewage Facility that is on a tract of land that is found to be in violation of the Hays County Development (Subdivision) Regulations.”
The state provision Hays overrode is 30 TAC § 285.3(f)(2), which waives planning materials, permit and inspections for a single-family home on ten acres or more, provided the system is at least 100 feet from every property line and the effluent stays on the property. Counties may adopt stricter rules than the state, and Hays did. Its Order says as much in the Section 10 preamble: “the more stringent local Rule shall take precedence over the corresponding Texas Commission on Environmental Quality requirements if local rules provide greater public health and safety protection.”
Several septic sites still publish the ten-acre exemption as live in Hays County. It is not. Our guide to the Texas ten-acre rule covers which counties have kept it and which have closed it.
The second sentence of 10.W.1 matters as much as the first. An unplatted tract that should have been platted gets no septic permit, and no county approval of any kind, until the platting is sorted out.
Applications are online only. The fee schedule is blunt about it: “Applications must be completed online at www.MGOConnect.org. Paper applications or documents will not be accepted or processed.”
The county asks for four things: the OSSF application; the site plan, design, location map, floor plan and tax account summary; a maintenance affidavit and two-year initial maintenance contract for advanced systems; and the fees.
Then, in the county’s own description of the sequence: an administrative review that “may take several business days,” assignment to an inspector for technical review, issuance of the authorization to construct during that technical review, and a notice of approval at the end.
The county publishes no technical-review turnaround and no total timeline. Any week-count you have read for Hays County came from somewhere other than Hays County.
What it does publish are three deadlines that start once you have the authorization to construct, from Section 10.W.2:
A tax balance will stop the permit. The county’s example-document sheet states that the tax account summary “must show a $0.00 remaining balance from the previous tax year. A permit may not be issued on any property with outstanding tax payments.”
Hays also asks for more on the site plan than the state does. Section 10.J requires topographic lines at one-foot intervals across the OSSF area and 25 feet beyond it, every well including wells on neighboring property, a tank battery flow diagram, and full calculations for hydraulic loading, wastewater strength, total head, dosing volume and pump tank reserve.
Nobody installed a standard trench or bed system under the county’s authority in 2025. TCEQ’s report of systems installed by time period, covering calendar 2025, records 131 authorizations to construct issued by the Hays County Authorized Agent:
| System type | Authorizations, 2025 |
|---|---|
| Surface irrigation | 55 |
| Drip irrigation | 53 |
| Leaching chamber | 13 |
| Low pressure dosing | 9 |
| Evapotranspiration bed | 1 |
| Standard trench or bed | 0 |
That 131 covers only the county’s own jurisdiction; the four self-permitting cities report separately. Statewide in the same year TCEQ recorded 41,990 authorizations, of which 3,105 were standard trench or bed. Hays issued none.
The soil explains it. The NRCS survey covering Hays County rates every component of its six dominant map units “Very limited” for septic tank absorption fields, which is the most restrictive class NRCS assigns. The limiting reasons split geographically: across the western and central county the Comfort, Brackett, Real and Eckrant soils are rated for depth to bedrock and for large stone content, while the eastern Blackland soils such as Houston Black are rated for slow percolation. Shallow rock in one half, tight clay in the other, and very little in between that will take a gravity drainfield.
Which is why the practical answer in Hays County is usually an aerobic treatment unit with spray or drip dispersal. Our aerobic septic system cost guide covers what that runs in Texas, and the new septic system cost guide covers the full install.
An advanced system in Hays County is a standing obligation, not a one-time approval.
Testing runs every four months unless the permit says otherwise, under Section 10.V.2, with the first report due within 14 days of the contract starting. If a test comes back off-spec — short chlorine residual, or the system otherwise not functioning — Section 10.V.4 gives the owner 10 days to correct it, retest, and get a new report to both the owner and the county. That clock does not push back the regular schedule.
Maintenance has to be done by a TCEQ-licensed provider who is also registered with Hays County. Registration runs to December 31 each year and is free, but it has teeth: a provider who misses testing intervals or files late twice in any 12 months can be suspended for up to a year, and Section 10.V.5 says that when that happens, “Outstanding contracts from a suspended maintenance provider will be void and property owners will need to submit a new contract with a registered maintenance provider.” Your contract can be canceled by your provider’s conduct, and the obligation lands back on you.
On a sale, the maintenance affidavit binds the owner to request transfer of the OSSF permit to the buyer, and a signed contract must reach Development Services within 30 days of the transfer. Our aerobic maintenance contract guide explains what those contracts have to contain.
There is no downloadable application PDF, by design — applications go through MyGovernmentOnline. What the county does publish:
The designer list carries two license types and only two: Registered Sanitarian and Professional Engineer. There is no county aerobic maintenance contract template; Section 10.K.3 instead sets out what the contract must contain, including the permit number, the provider’s license identification, both signatures, the start and end dates, and the maintenance company’s emergency phone number.
Looking for a licensed installer? Our Hays County directory lists TCEQ-licensed providers working in the county, and our septic installation service page covers what the work involves.
$610 for a single-family residence, plus a $10 state fee, under the schedule effective January 1, 2026. Non-single-family applications are $910 plus the same $10. A minor alteration is $310 and a major alteration $510, each plus $10. Reinspection is $150.
Yes. Order Section 10.W.1 requires a permit “for all On-Site Sewage Facilities, regardless of the size of the lot or acreage onto which it is installed.” Hays County adopted a stricter rule than the state’s ten-acre provision at 30 TAC § 285.3(f)(2), which it is entitled to do.
The county does not publish a turnaround. It describes an administrative review that “may take several business days,” followed by a technical review with no stated duration. Once you hold the authorization to construct, you have 12 months to complete the construction inspection and 14 months to finish construction, and no more than 18 months from the date you applied.
It depends on your aquifer zone and your water source, not on a single countywide number. Table 10-1 ranges from half an acre for an advanced system on surface water outside the aquifer zones to five acres for a conventional system on a private well in the recharge zone. New subdivisions on private wells inside the Priority Groundwater Management Area need six acres.
No, but the ground and the lot-size table push most projects there. No section of the Order mandates aerobic treatment by zone, soil or lot size. A conventional system needs one to three more acres than an advanced one on the same lot, and NRCS rates every dominant soil in the county “Very limited” for absorption fields. In 2025 the county authorized 108 spray or drip systems and zero standard trench or bed systems.
Hays County, not the City of Wimberley. The city’s own on-site sewage facility page states that OSSFs “will now be permitted through Hays County.” The four Hays County cities that do permit their own are San Marcos, Dripping Springs, Niederwald and Uhland.
Fees come from the Hays County Development Services Fee Schedule effective January 1, 2026, read in full as published. Regulatory text is quoted from the Hays County On-Site Sewage Facility Regulations, adopted by Commissioners Court on June 4, 2013 and approved by the TCEQ Executive Director on February 18, 2014, which remains the order TCEQ holds on file for authorized agent 620098 as of August 31, 2026. Jurisdiction is taken from TCEQ’s authorized-agent record for Hays County and corroborated against the City of Wimberley’s own page.
State provisions are cited to 30 Texas Administrative Code §§ 285.3 and 285.40. Installation counts are from TCEQ’s “Types of Systems Installed by Time Period” report dated April 27, 2026, covering January 1 to December 31, 2025; the Hays County row and the report’s printed grand total are quoted as published, and the two-category sum of spray and drip is our arithmetic on those figures.
Soil ratings are the USDA-NRCS published interpretation for septic tank absorption fields in survey area TX604, queried through Soil Data Access on August 31, 2026. The characterisation of which map units dominate the Hays County portion of that survey area is our own analysis of NRCS per-map-unit acreages, not an NRCS-stated ranking.
One requirement in the county’s Order has no published price: the annual registration to operate required by Section 10.K.1. We have asked the county and will publish the figure when we have it from them. We have not estimated it.
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