You’ve bought some land and…

You’re about to spend $15,000-$25,000 on a septic system.

If you misjudged your contractor or took a extremely low bid, you could be facing raw sewage in your yard, a failed inspection, or a complete system replacement within a few short years.

Texas soil doesn’t forgive shortcuts, and neither does the Texas Commission on Environmental Quality.

Here’s what separates a 30-year system from a 3-year nightmare.

Before You Even Get a Quote

1. “What’s your TCEQ installer license number?”

In Texas, septic installers must hold an active Installer License or On-Site Sewage Facility (OSSF) Installer License. Don’t just accept a business card. Go to TCEQ Search Licensing or Registration Information to verify current license.

Unlicensed installations are happening in rural areas, and you’ll be the one paying to rip it out and start over.

2. “Who’s designing my system, and are they a licensed Professional Engineer or Registered Sanitarian?”

Texas requires engineered designs for systems over 2,000 gallons per day or in challenging soil conditions. If they say “we’ll just use a standard design,” that’s your first red flag. Clay soils? High water table? Slopes? You need a PE stamp, period.

3. “Will you perform a complete site evaluation with soil testing?”

The installer should conduct percolation tests, soil profile analyses, and determine your soil’s absorption capacity. If they’re quoting without digging test pits, they’re guessing. Texas has everything from sandy loams to expansive clays, and the difference determines whether you need a conventional system ($15,000-$25,000) or an aerobic treatment unit with drip irrigation ($25,000-$45,000).

The Money Questions That Expose Bad Actors

4. “Does this quote include the TCEQ permit application and all county fees?”

Permit costs vary by county but typically run $200-$1,000. If it’s not itemized, you’re walking into surprise fees. Also ask: “Who’s responsible if the permit is denied?” A good installer builds permit cost into their proposal and handles resubmissions.

5. “What’s NOT included in this price?”

Septic quotes are notorious for hidden costs. Push for specifics: Is the electrical hookup included for aerobic systems? What about the control panel? Landscaping restoration? The sprinkler heads for spray distribution? Some contractors lowball by $5,000-$8,000, then hit you with “change orders” once equipment is on-site.

6. “What’s your payment schedule, and what protections do I have?”

Never pay more than 10% upfront. Standard is: 10% to start, 40% when materials arrive, 40% when installation is complete, and 10% after final inspection passes. If they want 50% down before breaking ground, they’re either cash-strapped or planning to disappear.

The Technical Deep Dive

7. “What size tank are you proposing, and how did you calculate it?”

Texas requires minimum 1,000-gallon tanks for 3-bedroom homes, but under sizing is rampant. The calculation should account for bedrooms, water fixtures, garbage disposals (which add 50% to capacity requirements), and future additions. An undersized tank means pumping every 8 months instead of every 3-5 years.

8. “What specific type of system are you recommending, and why?”

Conventional, aerobic treatment, drip irrigation, low-pressure dosing, mound systems—each has specific applications. If they can’t explain why your soil type, lot size, and setback requirements led them to this specific design, they don’t understand your property.

9. “What’s the brand and model of every major component?”

This matters enormously. Aerobic units from Norweco, Clearstream, or Jet have 20+ year track records. Generic units? Good luck finding parts in 5 years. Same for effluent pumps, control panels, and sprinkler heads. Get it in writing. No “equivalent” substitutions without approval.

10. “How deep is the water table on my property, and how does that affect the design?”

If groundwater is within 4 feet of the surface during wet seasons, you need either a raised bed system or an engineered solution. Installing a conventional drain field in a high-water table is creating a ticking time bomb. They should have done a site evaluation during wet season or reviewed well logs.

The Compliance Minefield

11. “What are the setback requirements for my property, and have you verified them?”

Texas requires minimum distances from wells (150 feet), property lines (5-10 feet), buildings (5-10 feet), and water bodies (50-150 feet depending on classification). County requirements may be stricter. If they haven’t measured and documented compliance, your system could fail inspection after installation.

12. “Will I need a maintenance contract, and what does Texas law require?”

Aerobic systems in Texas MUST have a maintenance contract with a licensed maintenance provider for the first two years minimum. This costs $300-$500 annually. If the installer doesn’t mention this, they’re either ignorant of the law or hiding the true cost of ownership.

13. “What inspections are required, and who schedules them?”

You need at least three inspections: initial site evaluation, mid-installation (before backfilling), and final. The installer should coordinate with the county inspector or TCEQ authorized agent. Ask: “What happens if we fail inspection? Who pays to fix it?”

The Disaster Prevention Questions

14. “What’s your warranty, and what specifically does it cover?”

Texas doesn’t mandate septic warranties, so everything is negotiable. A solid installer offers 1-3 years on workmanship and passes through manufacturer warranties (typically 2-3 years on aerobic units). Get it in writing. “Standard warranty” means nothing without documentation.

15. “Can you provide three references from installations in the last 18 months in similar soil conditions?”

Not just any references—recent ones, in comparable settings. Call them. Ask about change orders, timeline accuracy, and system performance. If the installer hesitates or provides only ancient references, that tells you everything.

16. “What’s your timeline, and what could delay it?”

Weather, permit processing (4-8 weeks in some counties), equipment availability, and inspection scheduling all effect timing. A realistic installer provides a range and explains contingencies. Someone promising “two weeks start to finish” is either lying or skipping critical steps.

17. “If my system fails in three years, will you be in business to stand behind your work?”

Check their business history. How long have they operated? Are they incorporated or just a guy with a backhoe? Do they carry general liability insurance ($1M minimum) and workers comp? Request certificates of insurance. Small operators vanish. Systems last decades. Do the math.

The Question You Must Ask Yourself

Here’s the one nobody mentions: “Am I choosing this installer because they’re cheapest, or because they’re best?”

A $12,000 quote seems attractive next to a $28,000 proposal. But that low bidder is probably skipping the engineered design, using a 1,000-gallon tank where you need 1,500, installing a conventional system in marginal soil that needs aerobic treatment, and will be bankrupt before your one-year anniversary.

Texas soil, weather, and regulations don’t care about your budget. They care about physics, microbiology, and law. Compare each bid, apples to apples.

Your septic is one of the most important systems on your property you never think about—until it fails. Then it’s the only thing you can think about, and you’re writing checks with extra zeros.

The guy who welcomes these questions is the one who will do it right.

Need help navigating Texas septic regulations? Texas Land Services connects property owners with licensed, vetted septic professionals who actually answer these questions. Because your investment deserves more than guesswork.