New Septic Installation in Montgomery County, Texas
Licensed, bonded septic system installation for Montgomery County — Magnolia, Montgomery, Willis, New Caney, Splendora, Pinehurst and the surrounding rural communities.
Licensed & Bonded
Texas OSF installer
Permitted & Inspected
County health-dept approved
New Installs Only
Built right the first time
Free Estimates
No-obligation, on-site
Your Montgomery County septic installer
Across Montgomery County's rural land, most homes run on their own on-site septic system instead of city sewer. We design, permit, and install new septic systems for new construction, manufactured, and mobile homes throughout the county — including Magnolia, Montgomery, Willis, New Caney, Splendora, Pinehurst — handling the soil and percolation testing and the county OSSF permitting from start to finish.
We install new septic systems for homes across Montgomery County, from Conroe out to Magnolia, Montgomery, Willis, New Caney, Splendora, and Pinehurst. Much of the county is acreage, new construction, and manufactured homes outside city sewer lines, so an on-site septic system is simply how a home here gets wastewater handled. Whether you're building fresh or putting a manufactured home on raw land, we size and install the right system for your lot.
What we install in Montgomery County
Site Evaluation & Perc Testing
We evaluate your soil and run the percolation test that determines how well your ground absorbs water — the foundation of a system that works.
System Design & Sizing
We size the tank and drainfield to your home's bedroom count and your soil's absorption rate, then engineer a layout that fits your lot.
Permitting & County Approval
We prepare and submit your on-site sewage facility (OSF) permit application and coordinate approvals with your county health department.
Excavation & Site Prep
We prepare the site and excavate for the tank and drainfield with the right grade and setbacks — protecting your wells, structures, and property lines.
Tank Installation
We set the septic tank, connect the inlet and outlet plumbing at the correct grade, and install the effluent filter and risers for easy future access.
Drainfield Installation
We install the drainfield (leach field) that disperses treated effluent safely into the soil, sized to your percolation results and available area.
We handle Montgomery County permitting
On-site sewage facilities (OSSF) are permitted at the county level. We prepare the application, submit the soil and design documentation, and see it through approval and final inspection — so your Montgomery County system is fully permitted and passes the county inspection.
In Montgomery County, your septic permit goes through Montgomery County Environmental Health Services (the On-Site Sewage Facilities program). Before we build, the property needs a site evaluation with a soil analysis from a Registered Site Evaluator, plus an OSSF design sealed by a Registered Sanitarian or professional engineer (submitted in three sets) along with signed floor plans and the property's floodplain status. We handle the Application for Permit to Construct at the county Permit Office at 501 N. Thompson, Suite 100 in Conroe, and after installation we request the Notice of Approval inspection before any backfill. As your installer, we take care of these steps so you don't have to chase the paperwork.
Local OSSF permitting authority: Montgomery County Environmental Health Services
Typical county permit fee: Set by the county — we confirm the current amount during permitting.
New to septic? Our guides cover the basics: How Much Does a New Septic System Cost in Texas? (2026) · What Size Septic Tank Do I Need? · What Is a Perc Test (and Why Does It Matter)?
Soil & site conditions in Montgomery County
Montgomery County actually spans two different soil zones, and that decides what your system needs. The southern and eastern parts of the county tend to have fine, clay-rich Beaumont and Lissie soils that drain slowly and can sit over a seasonal high water table, while the northern county around Conroe and Willis has sandier, loamier Willis-Formation soils in the pineywoods. Heavy clay lots usually call for an aerobic treatment unit with spray or drip dispersal, while sandier lots up north may allow a conventional or low-pressure dosed system. The on-site soil analysis is what sets your system class, so we never guess.
Cities & towns we serve in Montgomery County
- Magnolia
- Montgomery
- Willis
- New Caney
- Splendora
- Pinehurst
- Porter
- Cut and Shoot
- Dobbin
- Decker Prairie
- Stagecoach
- Woodbranch
- Patton Village
- Roman Forest
- Panorama Village
- Grangerland
- Porter Heights
- Conroe
We also install new septic systems across the rest of our service area: Harris County · Fort Bend County · Waller County · Liberty County.
Montgomery County septic questions
Do I need a permit for a septic system in Montgomery County?
Yes. A new on-site sewage facility (OSSF) requires a county permit plus a soil/site evaluation before installation. We handle the full permitting process for you, start to finish.
How much does a septic system cost in Montgomery County?
It depends on your soil type, system type, and drainfield size. Use our instant estimator for a ballpark, then we confirm the exact price after a free on-site evaluation.
Do you install septic systems for manufactured and mobile homes?
Yes — manufactured and mobile homes on rural Montgomery County land are what we install most. We size and permit the right system for your home and lot.
Who issues the septic permit in Montgomery County, and what does it cost?
Permits are issued by Montgomery County Environmental Health Services through its On-Site Sewage Facilities (OSSF) program. You'll pay a county permit fee plus a $10 TCEQ state fee. The county adopted a new health fee schedule effective September 1, 2025, so the current county fee amount should be confirmed directly with Montgomery County (the Permit Office can be reached at (936) 539-7839).
What are the steps to get a septic permit here?
First, a Registered Site Evaluator performs a site evaluation with a soil analysis. Then an OSSF design is prepared and sealed by a Registered Sanitarian or professional engineer, submitted in three sets, along with signed floor plans and the property's floodplain status. The Application for Permit to Construct is filed at the Montgomery County Permit Office (501 N. Thompson, Suite 100, Conroe). After we install the system and before any backfill, we request the Notice of Approval inspection. As your installer, we manage these steps for you.
Why do so many Montgomery County lots need an aerobic system?
It comes down to the soil. The southern and eastern parts of the county have fine, clay-rich Beaumont and Lissie soils that percolate slowly and can sit over a seasonal high water table, which commonly calls for an aerobic treatment unit with spray or drip dispersal. The sandier, loamier Willis-Formation soils in the northern county around Conroe and Willis may instead allow a conventional or low-pressure dosed system. Your on-site soil analysis sets the system class, so the design always matches your specific lot.
Can you install a septic system for a manufactured or mobile home on Montgomery County land?
Yes. A lot of work here is new construction and manufactured homes placed on acreage outside city sewer, and those homes need an on-site septic system. We size and install the system to match the home and the lot's soil. The permit process through Montgomery County Environmental Health Services is the same, including the required site evaluation, sealed OSSF design, and Notice of Approval inspection before backfill.
How much land do I need for a septic system in Montgomery County?
Montgomery County guidance is generally about 0.75 acre minimum for a lot without a private well, and roughly 1.5 acres if the property has a well. The exact requirement depends on your soil analysis and system design. We can review your lot during the site evaluation step before installation.
How long is a Montgomery County septic permit good for, and is anything extra needed in Precinct 4?
A permit to construct expires 180 days after it enters the system, so the install needs to move forward within that window. If your property is in Commissioner Precinct 4, the county also requires a Precinct 4 verification/culvert form as part of the process. We'll flag whether that applies to your property up front.
Get your free Montgomery County estimate
Tell us about your property and we'll size your system and schedule a free, no-obligation on-site evaluation.
Serving property owners across the region
Counties We Serve
Don't see your county?
We're often able to serve nearby areas too. Reach out with your property's location and we'll let you know if we can help.
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