Harris County Septic Regulations: What Homeowners Need to Know in 2026

Harris County septic permits cost $250-$300, require a minimum 2-acre lot, and take 30 business days to process through the county's ePermits system.

Harris County has the largest septic system population of any county in Texas. The Office of the County Engineer's Wastewater Quality Permitting division handles all septic permits in unincorporated areas. If you live in unincorporated Harris County with a septic system, the rules here go beyond what TCEQ requires statewide. The county's 2-acre lot minimum, flood plain restrictions, and mandatory replacement area requirements all add layers that homeowners in other Texas counties don't face.

This guide covers everything you need to know about septic permits, fees, inspections, and enforcement in Harris County. If you're installing a new system, repairing an existing one, or just trying to stay in compliance with your aerobic unit, you'll find the specifics here.

Key Requirement	Harris County Rule	Typical Texas County
Minimum lot size	2 acres (1.5 acres soil-suitable)	0.5-1 acre
Permit fee (residential)	$250-$300	$100-$250
Review timeline	30 business days	10-20 business days
Flood plain rules	"No net fill" policy, Floodplain Easement required	State minimum only
Replacement area	Full duplicate system space required	Varies by county
Aerobic reporting	Every 4 months to county	Per TCEQ standard (varies)

Who Handles Septic Permits in Harris County?

The Harris County Office of the County Engineer (OCE), specifically the Wastewater Quality Permitting division, issues all septic permits in unincorporated Harris County.

This is a common source of confusion. Many homeowners assume Harris County Public Health handles septic permits. They don't. The OCE's wastewater team reviews plans, issues construction authorizations, and conducts inspections.

Per TCEQ's On-Site Sewage Facilities program, Harris County operates as an "authorized agent" under 30 TAC Chapter 285. That means the county administers the state's septic program locally but can impose stricter rules than the state minimum. And Harris County does exactly that, particularly around lot sizes and flood plains.

Contact information:

Detail	Information
Office	Harris County Permits Office
Address	1111 Fannin Street, 1st Floor Lobby, Houston, TX 77002
Phone	(713) 274-3900
Hours	7:30 a.m. to 4:30 p.m., Monday through Friday
Online portal	epermits.harriscountytx.gov
Inspections line	(713) 274-3800

All permit applications must go through the ePermits online platform. You'll need to create an account, locate your property on the interactive map, and select the residential septic system application type. Make sure you pick the right application type the first time. Choosing the wrong one delays processing.

What Are the Septic Permit Types and Fees in Harris County?

Residential septic permits in Harris County cost $250-$300 for new installations. Amendments to existing permits run $150, and commercial permits carry higher fees based on system complexity.

Here's what you'll pay for the most common permit types:

Permit Type	Fee	Notes
New residential septic install	$250-$300	Standard 30 business day review
Residential amendment (modification)	$150	Must reference original permit number
Commercial septic install	$300+	Varies by project scope
Commercial amendment	$300	Full commercial review applies
Reinspection (failed initial)	Varies	Required before reinspection is scheduled
Site evaluation / feasibility study	Professional fees	$300-$700 for soil testing alone

These are county permit fees only. Your total out-of-pocket will include professional engineer or registered sanitarian fees for plan preparation, soil testing, and the installation itself.

The 10-acre exemption: If your property is 10 acres or larger, contains only one single-family home with one septic system, and the disposal field is at least 100 feet from all property lines, you don't need a Harris County permit. But you still need a site evaluation, and your system must meet every technical standard in 30 TAC Chapter 285. The exemption only covers the first system on the property. A second home with its own system triggers full permitting.

How Does the Harris County Septic Permit Process Work?

The permit process takes roughly 30 business days from complete application to construction authorization, plus inspection time after installation.

Here's the step-by-step process:

1. Site evaluation. Hire a Professional Engineer (PE) or Licensed Registered Sanitarian to evaluate your soil, measure percolation rates, and identify system placement. If a new plat is needed, a formal feasibility study is required first.

2. Application submission. Submit through ePermits with your site evaluation, engineering plans, recorded affidavit (filed with the Harris County Clerk), flood insurance rate map showing your property, and acknowledgement of testing requirements.

3. County review. The Wastewater Quality Permitting division reviews your plans against Harris County's Local Order and 30 TAC Chapter 285. Standard review takes 30 business days. If your application is incomplete, they'll send it back, and the clock restarts.

4. Authorization to Construct. Once approved and fees paid, you receive authorization to begin installation. Only a licensed installer can do the work.

5. Pre-cover inspection. The installer must call (713) 274-3800 at least 24 hours before the system is ready for inspection. Nothing can be buried or covered until a county inspector signs off.

6. Certificate of completion. If the system passes inspection, you're cleared to operate. If it fails, you'll get a deficiency list and must pay reinspection fees before scheduling another visit.

How Do Harris County Septic Rules Differ from State Minimums?

Harris County's 2-acre minimum lot size, replacement system space requirement, and flood plain rules are all stricter than base TCEQ standards.

These are the biggest differences between Harris County and what you'd face in many other Texas counties:

Lot size minimums: Every single-family home needs at least 2 acres, with 1.5 acres of that meeting soil suitability standards. That's well above what some Texas counties require. If your lot has slopes above 5%, slow percolation rates (over 45 minutes per inch), or drainage issues, the county can require even more acreage.

Lot width requirements: Properties on public water need at least 100 feet of width in the area where the septic system will go. If you're on a private well, that jumps to 150 feet.

Replacement system area: Harris County requires enough unobstructed space for your current system plus an equally sized replacement system. This is forward-thinking but can be a problem on smaller lots. You can't build a pool, shed, or driveway over your replacement area.

Flood plain restrictions: If your property falls within the 100-year flood plain (a 1% chance of flooding in any given year), you'll face extra requirements. A Floodplain Easement must be noted on your property plat. Harris County enforces a "no net fill" policy, meaning any reduction in flood plain storage from your septic installation must be offset with equivalent volume elsewhere on the property.

Deed recording: You must file a recorded affidavit with the Harris County Clerk's Office as part of the permit process. This puts future buyers on notice that the property has a permitted septic system.

What Are the Aerobic System Requirements in Harris County?

Aerobic septic systems in Harris County require a maintenance contract with a licensed provider, inspections during every service visit, and reports filed to the county every 4 months.

If you have an aerobic treatment unit (and many Harris County properties do, given the soil challenges), here's what the county expects:

Maintenance contracts are mandatory. Under 30 TAC Chapter 285 and Harris County's Local Order, you must have a current contract with a TCEQ-licensed maintenance provider. The provider must hold either a Class II Installer license, a Class C or higher Wastewater Operator license, or have completed three years as a registered maintenance provider. They also need TCEQ-approved Basic and Advanced Aerobic System courses.

What the contract must include:

• Items covered by the service agreement
• Response time for complaints about system operation
• Name of the individual performing maintenance
• Frequency of routine visits
• Testing and reporting schedule
• Who handles disinfection unit maintenance

Reporting schedule: Your maintenance provider must submit reports to Harris County and to you every 4 months. If your system uses electronic monitoring that automatically alerts the provider of failures, that reporting drops to every 6 months.

Service visit requirements: The provider must install a tag on your system at the start of each contract. They punch or mark it during every visit (including complaint responses) so you have a visual record. They inspect all components during each visit and note whether everything is working.

Maintenance contract costs: Budget $500-$700 every two years for a standard aerobic maintenance contract. That's on top of any repair costs if components fail.

Failure to maintain a current contract can result in misdemeanor violations handled through Harris County's Justice of the Peace Courts.

What Happens If You Violate Septic Rules in Harris County?

Harris County gives property owners 30 days to fix septic violations. If you don't comply, the county files a criminal complaint with the Justice of the Peace.

The county's enforcement approach is straightforward. They identify a problem, give you time to fix it, then escalate if you don't.

What triggers enforcement:

• Operating without a permit
• Installing or modifying a system without authorization
• Failing to maintain an aerobic system contract
• Systems causing a nuisance (odors, surface sewage, contamination)
• Failing a required inspection and not correcting deficiencies

The 30-day window: When the county identifies a violation, you typically get 30 days to remedy it. For situations involving standing or flowing wastewater, the 2026 TCEQ rule changes are eliminating the ability to simply "wait out" the 30 days while raw sewage sits on the ground.

Criminal complaints: If you don't fix the problem within the correction period, Harris County files a misdemeanor complaint through the Justice of the Peace Courts. This applies to both permit violations and maintenance contract lapses.

Unpermitted work: All septic installation, repair, and alteration work requires a permit and must be done by a licensed installer. The one narrow exception: homeowners can maintain (not install or repair) their own conventional system for their single-family home. For aerobic systems, you may be able to self-maintain after two years if you complete a 6-hour TCEQ-approved Basic Wastewater course, but check with Harris County directly since they can impose stricter rules.

How Much Does Septic Work Cost in Harris County?

A conventional septic system in Harris County runs $6,300-$9,900 installed, while aerobic systems cost $7,800-$12,000. Add $550-$1,000 for permits and site evaluation.

Here's what homeowners in the Houston area should budget:

Item	Cost Range
Conventional system install (3-bedroom)	$6,300-$9,900
Aerobic spray system	$7,800-$9,800
Aerobic drip system	$9,800-$12,000
Site evaluation and soil testing	$300-$700
County permit fee	$250-$300
Septic pumping (1,000-gallon tank)	$235-$280
Aerobic maintenance contract (2 years)	$500-$700
Typical repair (per hour + materials)	$275-$375/hour
Drain field replacement	$5,000-$12,000

According to Harris County's Infrastructure Design Manual, costs run higher here than in many rural Texas counties. The 2-acre lot requirement, flood plain complications, and Houston-area labor rates all push prices up. Properties with poor soil drainage that require aerobic or mound systems can add $5,000-$10,000 to a project.

For a full breakdown of Texas septic costs, see our septic pumping cost guide.

Frequently Asked Questions

Do I need a permit for septic work in Harris County?

Yes, almost always. New installations, repairs, and modifications all require a permit through Harris County's ePermits system. The only exception is the 10-acre exemption for single-family homes on large lots with proper setbacks. Routine pumping does not require a permit.

How much does a septic permit cost in Harris County?

Residential permits cost $250-$300. That's just the county fee. Budget another $300-$700 for the required site evaluation, plus professional engineer fees for plan preparation. Amendments to existing permits cost $150.

Who inspects septic systems in Harris County?

The Harris County Office of the County Engineer's Wastewater Quality Permitting division handles all inspections. Your licensed installer must call (713) 274-3800 at least 24 hours before the system is ready. The county inspector must approve the installation before any components can be covered.

Can I do my own septic work in Harris County?

Installation and repairs must be done by a licensed installer. For conventional systems, homeowners can perform basic maintenance on their own single-family home's system. For aerobic systems, you may qualify to self-maintain after completing a 6-hour TCEQ course, but Harris County may have stricter rules. Call (713) 274-3900 to confirm.

How do flood plain rules affect my septic system in Harris County?

If your property is in the 100-year flood plain, expect extra requirements and costs. You'll need a Floodplain Easement on your plat, and Harris County's "no net fill" policy means any fill used for your septic installation must be offset with equal flood storage volume elsewhere on your property. Post-Hurricane Harvey, the county has tightened enforcement of flood plain development. Contact the Permits Division at (713) 274-3900 for an unofficial determination of your property's flood status before you plan any septic work.

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Last updated: February 7, 2026 Reviewed by: Texas Septic Guide Editorial Team, content verified against TCEQ regulations, Harris County Office of the County Engineer records, and 30 TAC Chapter 285

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Sources: Harris County Office of the County Engineer, Wastewater Quality Permitting Division; Texas Commission on Environmental Quality (TCEQ), 30 TAC Chapter 285; Harris County Infrastructure Design Manual; Harris County Local Order for On-Site Sewage Facilities.

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