Septic System Installation in Jefferson County
A new or replacement system in Jefferson 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 ground is the deciding factor in Jefferson 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.
- 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
- 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 Jefferson County
License-verified contractors (active state license) are listed first.
A and P Excavating and Materials
Verified · Lic. 11723AA Land Development
Verified · Lic. 14833Aaron Thurman
Verified · Lic. 11682Action Excavating and Land Clearing
Verified · Lic. 19019Adriel
Verified · Lic. 14350Affordable East Tennessee Septic Service
Verified · Lic. 1030Alex gibson
Verified · Lic. 19576All Seasons Lawncare & Landscaping
Verified · Lic. 13155All Tasks LLC
Verified · Lic. 19354Allen's excavating and construction
Verified · Lic. 10515Anderson farms
Verified · Lic. 18005Ascent Contractors LLC
Verified · Lic. 13338B&B Construction
Verified · Lic. 14346B&L Bobcat & Excavating
Verified · Lic. 14837Backwoods Earth Works LLC
Verified · Lic. 14357Banks' Land Improvements
Verified · Lic. 19266Barbee's Excavation LLC
Verified · Lic. 19557Barnett & Sons Wood and Dirt
Verified · Lic. 12900Barton Contracting & Excavating LLC
Verified · Lic. 13836Bazan Construction Inc
Verified · Lic. 14037Ben & William Naillon's Construction
Verified · Lic. 12633Ben's Bobcat
Verified · Lic. 18507Benjamin MacIsaac
Verified · Lic. 18860Berryhill Excavating
Verified · Lic. 19311Betterbuild
Verified · Lic. 13151Bill's Excavating LLC
Verified · Lic. 13805BIR Developments, LLC
Verified · Lic. 18205Black Iron Septics LLC
Verified · Lic. 15117Black Rock Excavating
Verified · Lic. 19077Septic System Installation in Jefferson County — FAQ
What does a new septic system cost in Jefferson 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 Jefferson County are the biggest cost driver.
Do I need a permit to install a septic system in Jefferson County?
Yes. Permits are issued by the Local authorized agent / county health department in Jefferson 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.