When you need a new septic system
If your Houston-area home isn't on a city sewer line — most properties outside Beltway 8 and the larger annexed cities — you're on septic. New construction, failed systems, or major remodels that add bedrooms all trigger a new install or upgrade.
In Harris, Montgomery, Fort Bend, Brazoria, Galveston, Chambers and Waller counties, on-site sewage facilities are regulated by the county's Permitting & Environmental Health office under TCEQ Chapter 285.
Aerobic vs conventional in the Houston area
Most of Greater Houston has clay-heavy soil with a high water table. That rules out conventional gravity drain fields on a lot of lots — which is why aerobic spray systems are the default for new installs across Cypress, Magnolia, Conroe, Tomball, Fulshear, Friendswood, Manvel and Mont Belvieu.
Conventional systems are cheaper ($7,500–$12,000 installed) but require well-drained soil and enough lot area for a gravity field. Aerobic systems cost more ($10,500–$16,000 installed) but work on almost any Houston-area lot and produce cleaner effluent.
The permit and install timeline
1. Soil and site evaluation by a licensed designer (1–2 weeks).
2. System design and county permit application (2–4 weeks).
3. Excavation and tank set (1–2 days).
4. Drain field or spray heads installed (1–2 days).
5. County final inspection and go-live (1–2 weeks).
Total: usually 5–9 weeks from first call to flushing.
What to ask your installer
Are you Texas-licensed for OSSF work?
Do you pull the county permit, or do I?
Is the 2-year aerobic maintenance contract included?
What's the workmanship warranty?