4 Seasons Contracting
Verified · Lic. 18233Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Knox County, TN · Septic System Installation
Septic System Installation in Knox County
A new or replacement system in Knox County starts with a soil test and a permit — not a shovel.
Installing a septic system is the largest-ticket job a septic owner faces, and the design is dictated by your land: soil type, how fast it percolates, and how high the water table sits all decide what system you're allowed to build and what it costs.
Every legal install begins with a site evaluation and a county permit. The output of that evaluation — conventional drainfield, engineered mound, or an aerobic/nitrogen-reducing unit — is what drives the final price far more than the tank itself.
Local conditions in Knox County
Local ground is the deciding factor in Knox County: Steep terrain causes effluent to surface or move laterally; karst valleys (Knox/Hamilton) carry the same fracture-flow contamination risk as Middle TN And the rules here matter — slope limits (commonly no systems on slopes steeper than ~25%) frequently force alternative designs or block construction, which can raise the cost of a new system considerably.
How a septic installation works
- Site & soil evaluation. A licensed evaluator or engineer tests percolation and locates the seasonal high water table to determine what the soil can handle.
- System design. The system is sized to your soil and the number of bedrooms, and the type is chosen — conventional, mound/filled, or aerobic.
- County permit. Plans are submitted to the county health department for an OSTDS construction permit before any work begins.
- Tank and drainfield install. The tank is set and the drainfield is built to spec, with fill brought in where the water table requires elevation.
- Final inspection. The county inspects the open system and signs off before it's covered and put into use.
What drives the cost
- System type — conventional vs. mound vs. aerobic/nitrogen-reducing
- Soil and water table (high water tables require expensive fill)
- Drainfield size, which scales with bedroom count
- Permit and engineering/site-evaluation fees
- Site access and how much excavation is needed
- Tank material and capacity
How to choose a pro
- Use a licensed Registered or Master Septic Tank Contractor
- Make sure they pull the county permit (never skip it)
- Insist the design matches your soil/site evaluation
- Get the warranty and final county approval in writing
30 septic system installation providers in Knox County
License-verified contractors (active state license) are listed first.
A & P Works
Verified · Lic. 14385Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
A-1 ADVANCED ENERGY SOLUTIONS
Verified · Lic. 11700Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
A. Goedeke Services
Verified · Lic. 18094Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
A1 Septic Installers
Verified · Lic. 13503Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
AA Land Development
Verified · Lic. 14833Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
AAA SEPTIC LLC
Verified · Lic. 19559Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Abbey construction
Verified · Lic. 11359Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Abm Landscaping LLC
Verified · Lic. 14311Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Action Excavating and Land Clearing
Verified · Lic. 19019Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
adams Construction
Verified · Lic. 2188Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Adriel
Verified · Lic. 14350Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Advanced Heating & Air
Verified · Lic. 18947Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
AE SPALLONE CONSTRUCTION LLC
Verified · Lic. 19034Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Affordable East Tennessee Septic Service
Verified · Lic. 1030Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Pumper · TN TDEC · verified 2026-06-25
Alex gibson
Verified · Lic. 19576Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
All Season Lawn and More llc
Verified · Lic. 18122Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
All Seasons Lawncare & Landscaping
Verified · Lic. 13155Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Allen's excavating and construction
Verified · Lic. 10515Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Anderson farms
Verified · Lic. 18005Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Appalachian Construction
Verified · Lic. 19405Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Ascent Contractors LLC
Verified · Lic. 13338Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Atkins hauling and excavation
Verified · Lic. 19188Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
B&B Construction
Verified · Lic. 14346Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Banks' Land Improvements
Verified · Lic. 19266Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Barnett & Sons Wood and Dirt
Verified · Lic. 12900Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Barnwell Excavating
Verified · Lic. 10121Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Barrett’s excavating
Verified · Lic. 19061Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Bartley Excavating and Construction
Verified · Lic. 12613Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Barton Contracting & Excavating LLC
Verified · Lic. 13836Knoxville, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Septic System Installation in Knox County — FAQ
What does a new septic system cost in Knox County?
Conventional systems commonly run from several thousand dollars to well over $10,000; mound and nitrogen-reducing systems cost more. Soil and water-table conditions in Knox County are the biggest cost driver.
Do I need a permit to install a septic system in Knox County?
Yes. Permits are issued by the Local authorized agent / county health department in Knox County, under Tennessee Department of Environment and Conservation (TDEC), Division of Water Resources., and the system must pass inspection before use.
How long does an installation take?
Once permitted, the install itself is often 1–3 days, but evaluation and permitting can add weeks. Plan ahead.