Houston exurbs + DFW fringe
Septic permits near Houston: Harris, Fort Bend, and Montgomery counties
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Not legal advice. Rules below are summarized from TCEQ, Texas A&M AgriLife Extension, and county sources linked on this page. Local programs can be stricter than state minimums — confirm with your permitting authority before you act.
These notes cover what each county publishes on its own site as of the date above. Inside city limits, a city may be the permitting authority instead — check TCEQ’s authorized agent search. For statewide basics, see Texas septic rules and permits.
At a glance
| County | Who issues OSSF permits | Notable published rules |
|---|---|---|
| Harris | Office of the County Engineer — Watershed Protection, Wastewater Permitting (unincorporated Harris County), applications through ePermits | Plans designed by a Texas PE or licensed registered sanitarian; maintenance contract from a licensed Maintenance Provider on the submittal checklist |
| Fort Bend | Environmental Health Department (Health & Human Services) | Ongoing maintenance contract required for all systems with secondary treatment; local order bars homeowner self-maintenance unless certified and licensed |
| Montgomery | Environmental Health Services, On-Site Sewage Facilities program (Conroe) | No permits for systems in the regulatory floodway; minimum lot sizes; permits expire one year after Authorization to Construct |
Harris County
- Permitting office: the Office of the County Engineer’s Wastewater Permitting group reviews plans and issues OSSF permits in unincorporated Harris County. Residential applications go through ePermits (“Residential Onsite Sewage Facility (OSSF)/Septic”).
- Residential submittal checklist (per the county’s residential septic permit page): septic application with a valid address and HCAD number; Affidavit to the Public filed with the Harris County Clerk; Acknowledgement of Testing Requirement; site evaluation report by a professional engineer or registered site evaluator; survey if not in a recorded subdivision; scaled design site plan; technical report; system flow diagram; joinder affidavit if the system crosses property lines; and a maintenance contract from a licensed Maintenance Provider.
- Inspection: the licensed installer must notify the permit office at least 24 hours before the system is ready for inspection; failed inspections may carry re-inspection fees.
- Maintenance contracts: the county states that an owner of an approved, permitted OSSF is required to have a maintenance contract with a Maintenance Provider, and that failing to submit one can lead to misdemeanor violations handled in Justice of the Peace courts. Current contracts go to wastewater@harriscountytx.gov. If you’re unsure whether this applies to your system type, ask the county.
- Changing an approved design: amendments need a revised, sealed drawing; the published residential amendment fee is $150.
Fort Bend County
- Contract required: per the county’s aerobic maintenance information, ongoing maintenance contracts are required for all systems that use secondary treatment, and the owner must keep a valid contract in force at all times.
- First two years: new aerobic systems come with a two-year manufacturer service contract. After that you can renew with the same provider or pick another licensed Maintenance Provider.
- Renew 30 days early: renewal contracts are due 30 days before the current one expires, and a copy must be on file with the county. The county says failure to obtain a contract results in a Class C misdemeanor charge in Justice of the Peace court.
- No self-maintenance unless the owner is a certified maintenance provider for that unit and holds the required state licenses (Fort Bend local order) — stricter than the state minimum.
- Visits and reports: testing and reporting every 4 months; reports go to the county within 14 days of the test.
- Renewal fee: after the initial two-year contract, each renewal must be submitted with the county’s Annual Maintenance Contract Renewal Fee; contracts must list the OSSF permit number, and the county will not accept them by fax or mail. Check the county page for the current amount.
- Chlorine: owners must keep a chlorine residual of at least 0.1 mg/l whenever the system runs. Never use swimming-pool chlorine.
- Not covered unless your contract says so: pumping or cleaning tanks, maintaining the disinfection unit, replacing broken spray heads, power-failure damage, homeowner misuse.
- Permit packets: Fort Bend OSSF permits / packets. Phone listed by the department: 281-342-3411.
Montgomery County
- Permitting office: Montgomery County Environmental Health Services — On-Site Sewage Facilities, 501 N. Thompson, Conroe (OSSF line listed as 936-539-7839).
- New system steps (county handout “How to obtain a permit to construct a septic system”, revised March 22, 2023): site evaluation with soil analysis from a registered site evaluator; design from a registered sanitarian or registered professional engineer; owner-signed floor plans showing bedrooms, restrooms, and square footage; floodplain status from the permit office; three sets of the design.
- Floodway: the county will not issue permits for any septic system located within the regulatory floodway.
- Lot size: at least 0.75 acre without a private water well, or 1.5 acres with a septic system and a private well — with special consideration for lots recorded or on the tax rolls before December 1, 1986 (proof required).
- Permit life: the residential septic permit page says OSSF permits expire within one year of the Authorization to Construct date.
What this means for a Houston-area homeowner
| Situation | What to do |
|---|---|
| Routine pump-out | No homeowner permit. Hire a TCEQ registered sludge transporter and verify the registration. See the quote checklist and cost bands. |
| Aerobic system (spray heads, air pump, chlorinator) | Keep a current contract on file with the county; in Fort Bend, renew 30 days ahead with the renewal fee. See maintenance contracts. |
| Tank or drain field repair | Permit required statewide; the county (or city) is usually where you apply. See drain field repair. |
| Buying a home | Get the permit file and contract status from the county; transfer or replace the contract at closing. See buying a home with septic. |
| Flood-prone lot | See the heavy rain and flooding section in warning signs. |
Related guides
- Texas septic rules and permits (TCEQ basics)
- Aerobic maintenance contracts in Texas
- Buying a home with septic in Texas
- Septic pumping cost in Texas by tank size
- DFW-fringe county permit notes (Collin, Denton, Rockwall, Tarrant, Dallas)
Sources
- Harris permitting office, ePermits, maintenance contract statement, JP-court note, contract email, $150 residential amendment — Harris County OCE: Wastewater Quality Permitting
- Harris residential submittal checklist and 24-hour inspection notice — Harris County OCE: Residential Construction & On-site Sewage System (Septic)
- Fort Bend contract requirement, two-year manufacturer contract, 30-day renewal, Class C misdemeanor, self-maintenance prohibition, 4-month reporting, 0.1 mg/l chlorine residual, not-covered list, phone — Fort Bend County: Aerobic Maintenance Information
- Fort Bend renewal fee rules — Fort Bend County: Annual Maintenance Contract Renewal Fee; permit packets — Fort Bend OSSF Permits / Packets
- Montgomery program office and phone — Montgomery County Environmental Health: On-Site Sewage Facilities
- Montgomery new-system steps, floodway rule, lot sizes, pre-1986 lots — Montgomery County handout: How to Obtain a Septic (rev. 2023-03-22)
- Montgomery one-year permit expiry — Montgomery County: Septic Permit — Residential
- Authorized agent lookup — TCEQ OARS; statewide permit rules — TCEQ: Getting a Permit for an OSSF