Texas Septic System Statistics (2015–2024)

Texas counties authorized 431,535 new septic systems between 2015 and 2024. Permits climbed every year through 2022, peaked at 54,593, then fell 21% in two years to 43,215 in 2024. Underneath that curve sits a technology shift most Texans never notice, and a geography so consistent you can predict a household’s septic system from its ZIP code.

Every figure here is parsed from TCEQ’s own annual on-site sewage facility (OSSF) reports.

The boom and the correction

Texas septic permitting rose 72% from 2015 to its 2022 peak, then gave back a fifth of that in two years.

The shape is familiar to anyone who watched Texas homebuilding over the same decade: a long climb, a pandemic-era surge, then a sharp pullback as rates rose. What makes the septic version worth noting is that it tracks rural construction: houses built beyond the sewer line, on the exurban edge, where growth shows up first and retreats first. A county’s septic permit count works as a running census of how far the metro is spilling.

Even after the correction, 2024 ran 36% above 2015.

Where the systems are going

The top 10 counties account for 116,064 permits, just 26.9% of the statewide total, so Texas septic demand is far less concentrated than the state’s population.

Two patterns are worth reading. The metro cores on this list (Bexar, Harris, Travis) are all shrinking as sewer extensions eat away at their unsewered fringe. The counties one ring out are exploding.

Fastest-growing counties (among those permitting 50+ systems in 2015):

That is a map of the Texas Triangle’s outer edge: Ellis and Hill south of Dallas, Cooke and Grayson to the north, Grimes and Washington between Houston and Austin. Parker County at +76% is the same story on the DFW flank.

Permits fell hardest outside that growth belt. Titus County, in Northeast Texas, dropped 70%, from 57 systems in 2015 to 17 in 2024, the steepest decline of any county that permitted 50 or more systems in 2015. In the West Texas oil patch, Ward (−51%) and Andrews (−49%) lost roughly half their volume, their 2015 baselines inflated by a drilling cycle that has since cooled.

The quiet technology shift

Conventional buried drainfields are disappearing from Texas. Aerobic systems with surface spray now take 58% of installs, up from 52% a decade ago, while standard trench-and-bed fell from 14% to 8%.

Drip grew fastest in relative terms, up more than half, because it threads the needle on sites that cannot take a conventional field but where spray is unwanted: steep lots, small lots, aquifer zones with nitrogen limits.

The practical consequence is money. An aerobic system is not a tank you forget about; it is treatment equipment with a maintenance contract, required inspections, and electricity. When your county’s soils push you into that category, the cost shows up every year for the life of the house, not just on install day.

Texas is three septic countries

The most striking finding is not the trend but the geography: cluster the counties and the state resolves into three technology regions, each near-total in its dominance.

Some counties are unanimous. Upshur, Hopkins, Camp, and Angelina each permitted 100+ systems in 2024 and used aerobic spray for every single one. Gaines County used leaching chambers for 99% of 386. Hidalgo used gravel-less for 94% of 1,348. El Paso, alone among large counties, still puts 91% into standard trench and bed.

The dividing line is essentially a rainfall map. Wet East Texas timberland soils hold water, so effluent is treated and sprayed above ground rather than buried in saturated soil. Dry, permeable West Texas and the Valley still absorb effluent underground, so cheaper chamber and gravel-less systems stay viable.

This is why national septic cost averages are close to useless in Texas. A homeowner in Angelina County is buying a fundamentally different machine than one in Gaines County, and the price gap runs to thousands of dollars.

What the data doesn’t cover

Three limits shape what you can read off this dataset.

• These are new authorizations, not existing systems. Texas has hundreds of thousands of older septic systems that predate this window and never appear here. No statewide inventory of installed systems exists.
• Regional-office permits carry no county detail. TCEQ’s regional offices authorized roughly 1,100 systems per year in counties without a local agent. Those permits sit inside our statewide totals but carry no county attribution, which slightly understates the rural counties.
• “Other” and unclassified types appear in the source data and are excluded from technology-share percentages, which are calculated on typed installs only.

Sources & Methodology

Every figure on this page traces to TCEQ’s own annual OSSF permitting reports, parsed July 30, 2026, and reconciled against TCEQ’s published statewide totals.

We parsed TCEQ’s annual “Types of Systems Installed by Time Period” reports for 2015 through 2024, both the Authorized Agent series and the TCEQ Regional Office series, into a structured dataset of 3,509 agent-county-year records, each carrying a total and 12 system-type counts.

Validation: our parsed totals reconcile exactly with TCEQ’s published statewide total for all ten years, and every system-type column sums exactly to each report’s own total. All 130 column checks passed. Where a figure here disagrees with a secondary source, this dataset agrees with TCEQ’s PDFs.

County rankings use Authorized Agent records, which carry county attribution. Statewide totals include both series, so county-share percentages on this page are measured against the full 431,535, including the region-issued permits no county is credited with. Technology shares are calculated on typed installs.

• TCEQ, OSSF annual permitting reports, 2015–2024 (Systems Authorized by Authorized Agents; Systems Authorized by TCEQ Regional Offices), parsed July 30, 2026
• TCEQ, Licensing Query (lic_dpa), OSSF licensee registry, pulled July 30, 2026
• TCEQ, OSSF Authorized Agent directory (OARS), pulled July 30, 2026

The dataset is free to use. Journalists, researchers, county officials, and extension staff are welcome to it: email hello@nearbyseptic.com for the CSVs. Cite it as: Nearby Septic, “Texas Septic Systems by the Numbers (2015–2024),” derived from TCEQ OSSF annual permitting reports, published July 30, 2026.

If you find an error, tell us and we will correct it publicly. Our full data practices are in how we verify.

County-level detail, local rules, and permitting offices for all 254 Texas counties: browse by county. What routine service costs: septic pumping in Texas.