REPORT · PUBLISHED OCT 13, 2026 · CC BY 4.0
Texas aerobic septic permits in 2025
28,159 of the 41,990 on-site sewage facility authorizations in Texas in 2025 were aerobic systems: 67.1%, up from 57.9% in 2015. Aerobic authorizations rose from 17,870 in 2015 to 28,159 in 2025, an increase of 57.6%. The peak was 2022, with 35,187; 2025 was 20% below it.
Aerobic authorizations, year by year
Texas Authorizations to Construct: surface irrigation plus drip. TCEQ annual reports, 2015–2025; the underlying data and limits are unchanged.
- 201517,870
- 201619,909
- 201721,713
- 201823,602
- 201925,357
- 202029,222
- 202133,501
- 202235,187
- 202329,302
- 202428,094
- 202528,159
Key findings
- 28,159 of the 41,990 on-site sewage facility authorizations in Texas in 2025 were aerobic systems: 67.1%, up from 57.9% in 2015.
- Aerobic authorizations rose from 17,870 in 2015 to 28,159 in 2025, an increase of 57.6%. The peak was 2022, with 35,187; 2025 was 20% below it.
- Montgomery County recorded 1,834 aerobic authorizations in 2025, 6.5% of the state’s total and more than any other county.
- The ten counties with the most aerobic authorizations accounted for 32.1% of the 2025 total.
- Ellis County grew the most since 2015, from 153 aerobic authorizations to 806.
- Aerobic systems were the majority of 2025 authorizations in 101 of the 195 counties that reported any.
- TCEQ Region 04 (DFW Metroplex) had the most aerobic authorizations of the sixteen regions in 2025: 8,307.
- Drip dispersal was 13.4% of aerobic authorizations in 2025 (3,767), up from 10.3% (1,845) in 2015; the rest were surface (spray) application. The drip share peaked at 13.8% in 2024.
Statewide, 2015–2025
| YEAR | ALL OSSF | AEROBIC | AEROBIC SHARE |
|---|---|---|---|
| 2015 | 30,858 | 17,870 | 57.9% |
| 2016 | 33,342 | 19,909 | 59.7% |
| 2017 | 35,984 | 21,713 | 60.3% |
| 2018 | 39,045 | 23,602 | 60.4% |
| 2019 | 42,433 | 25,357 | 59.8% |
| 2020 | 46,603 | 29,222 | 62.7% |
| 2021 | 51,324 | 33,501 | 65.3% |
| 2022 | 53,391 | 35,187 | 65.9% |
| 2023 | 45,716 | 29,302 | 64.1% |
| 2024 | 42,097 | 28,094 | 66.7% |
| 2025 | 41,990 | 28,159 | 67.1% |
Spray or drip: how new aerobic systems disperse, 2015–2025
Drip dispersal was 13.4% of aerobic authorizations in 2025 (3,767), up from 10.3% (1,845) in 2015; the rest were surface (spray) application. The drip share peaked at 13.8% in 2024.
| YEAR | SURFACE (SPRAY) | DRIP | DRIP SHARE |
|---|---|---|---|
| 2015 | 16,025 | 1,845 | 10.3% |
| 2016 | 17,921 | 1,988 | 10% |
| 2017 | 19,619 | 2,094 | 9.6% |
| 2018 | 21,003 | 2,599 | 11% |
| 2019 | 22,701 | 2,656 | 10.5% |
| 2020 | 25,723 | 3,499 | 12% |
| 2021 | 29,161 | 4,340 | 13% |
| 2022 | 30,550 | 4,637 | 13.2% |
| 2023 | 25,321 | 3,981 | 13.6% |
| 2024 | 24,205 | 3,889 | 13.8% |
| 2025 | 24,392 | 3,767 | 13.4% |
Drip share is drip as a share of aerobic authorizations (spray plus drip), statewide. It is not published per county: in a few county-years the TCEQ type columns add up to more than that county’s total authorizations, so a county share would not be reliable. Each county page shows its own spray and drip counts by year.
The ten counties with the most aerobic permits in 2025
| # | COUNTY | AEROBIC 2025 | ALL OSSF 2025 | AEROBIC SHARE |
|---|---|---|---|---|
| 1 | Montgomery | 1,834 | 1,850 | 99.1% |
| 2 | Parker | 1,154 | 1,300 | 88.8% |
| 3 | Comal | 941 | 1,026 | 91.7% |
| 4 | Johnson | 844 | 888 | 95% |
| 5 | Smith | 832 | 938 | 88.7% |
| 6 | Ellis | 806 | 822 | 98.1% |
| 7 | Harris | 667 | 736 | 90.6% |
| 8 | Grayson | 656 | 681 | 96.3% |
| 9 | Hunt | 656 | 665 | 98.6% |
| 10 | Brazoria | 654 | 675 | 96.9% |
Largest increases since 2015
| COUNTY | AEROBIC 2015 | AEROBIC 2025 | CHANGE |
|---|---|---|---|
| Ellis | 153 | 806 | +653 |
| Parker | 516 | 1,154 | +638 |
| Johnson | 296 | 844 | +548 |
| Smith | 346 | 832 | +486 |
| Grayson | 215 | 656 | +441 |
| Bell | 225 | 613 | +388 |
| Navarro | 17 | 387 | +370 |
| Hood | 155 | 495 | +340 |
| Hunt | 321 | 656 | +335 |
| Wise | 111 | 427 | +316 |
The sixteen TCEQ regions in 2025
| REGION | COUNTIES | AEROBIC 2025 | ALL OSSF 2025 | AEROBIC SHARE |
|---|---|---|---|---|
| Region 04 (DFW Metroplex) | 19 | 8,307 | 9,407 | 88.3% |
| Region 12 (Houston) | 13 | 5,689 | 6,023 | 94.5% |
| Region 05 (Tyler) | 23 | 4,211 | 4,552 | 92.5% |
| Region 09 (Waco) | 20 | 2,988 | 4,017 | 74.4% |
| Region 13 (San Antonio) | 15 | 2,470 | 4,416 | 55.9% |
| Region 11 (Austin) | 10 | 1,988 | 3,115 | 63.8% |
| Region 10 (Beaumont) | 15 | 1,286 | 1,587 | 81% |
| Region 14 (Corpus Christi) | 15 | 762 | 1,574 | 48.4% |
| Region 03 (Abilene) | 30 | 405 | 1,360 | 29.8% |
| Region 16 (Laredo) | 10 | 22 | 173 | 12.7% |
| Region 07 (Midland) | 17 | 15 | 1,745 | 0.9% |
| Region 08 (San Angelo) | 13 | 14 | 401 | 3.5% |
| Region 01 (Amarillo) | 26 | 2 | 613 | 0.3% |
| Region 02 (Lubbock) | 15 | 0 | 604 | 0% |
| Region 06 (El Paso) | 6 | 0 | 221 | 0% |
| Region 15 (Harlingen) | 7 | 0 | 2,182 | 0% |
Method and limits
- Counts are Authorizations to Construct from the eleven annual TCEQ “Types of Systems Installed” reports, 2015–2025, as assembled on Oct 5, 2026.
- “Aerobic” is surface irrigation plus drip. Both require aerobic pretreatment, so together they count new aerobic systems.
- An authorization is a permit to build, not a count of systems in service.
- 59 counties reported no authorizations at all in 2025. Where the TCEQ regional office permits systems directly, they can be recorded against the region rather than a county.
- Shares are rounded to one decimal place. Everything here is recomputed from the per-county rows in the CSV, which anyone can check.
How we research and check our data. Not legal advice.
How to cite this report
DulyTrack, “Texas aerobic septic permits in 2025,” Oct 13, 2026, https://dulytrack.com/data/texas-aerobic-permits-2025. Data: TCEQ “Types of Systems Installed” reports, 2015–2025. CC BY 4.0.
Free to reuse with attribution under CC BY 4.0.
Common questions
How many aerobic septic systems were permitted in Texas in 2025?
28,159 of the 41,990 on-site sewage facility authorizations in Texas in 2025 were aerobic systems: 67.1%, up from 57.9% in 2015.
Which Texas county permits the most aerobic septic systems?
Montgomery County recorded 1,834 aerobic authorizations in 2025, 6.5% of the state’s total and more than any other county.
Are aerobic septic permits growing in Texas?
Aerobic authorizations rose from 17,870 in 2015 to 28,159 in 2025, an increase of 57.6%. The peak was 2022, with 35,187; 2025 was 20% below it.
Are more Texas aerobic systems using drip instead of spray?
Drip dispersal was 13.4% of aerobic authorizations in 2025 (3,767), up from 10.3% (1,845) in 2015; the rest were surface (spray) application. The drip share peaked at 13.8% in 2024.
Where does this data come from?
The eleven annual TCEQ “Types of Systems Installed” reports, 2015 to 2025, which count Authorizations to Construct by county and by system type. Aerobic means surface irrigation plus drip, both of which require aerobic pretreatment.
Look up any county’s permitting authority and filing channel on the Texas county pages, see where maintenance providers are based, or the rules each report answers to.