SepticRoster
Find by ZIPGuidesCostsGet quotes
States
FloridaTexasNorth CarolinaGeorgiaTennessee
Williamson County, TN · Septic System Installation

Septic System Installation in Williamson County

A new or replacement system in Williamson County starts with a soil test and a permit — not a shovel.

See 30 verified pros

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 Williamson County

Local ground is the deciding factor in Williamson County: Effluent reaching bedrock fractures gets little filtration before entering the karst aquifer, so soil depth and sinkhole avoidance dominate permit approval And the rules here matter — sinkhole and karst-feature setbacks are strictly enforced; fields cannot discharge toward closed depressions, which can raise the cost of a new system considerably.

How a septic installation works

  1. Site & soil evaluation. A licensed evaluator or engineer tests percolation and locates the seasonal high water table to determine what the soil can handle.
  2. System design. The system is sized to your soil and the number of bedrooms, and the type is chosen — conventional, mound/filled, or aerobic.
  3. County permit. Plans are submitted to the county health department for an OSTDS construction permit before any work begins.
  4. 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.
  5. 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 Williamson County

License-verified contractors (active state license) are listed first.

“A” Tom Huff Company

Verified · Lic. 13273
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

4 Seasons Contracting

Verified · Lic. 18233
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

A Dirty Job Septic Service

Verified · Lic. 645
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Pumper · TN TDEC · verified 2026-06-25

A Team Footers and Excavation LLC

Verified · Lic. 18977
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

A-TEAM SEPTIC

Verified · Lic. 13212
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

AA Land Development

Verified · Lic. 14833
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Abm Landscaping LLC

Verified · Lic. 14311
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Adams Backhoe

Verified · Lic. 420
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Adriel

Verified · Lic. 14350
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Advanced Lawn and Land, LLC.

Verified · Lic. 19594
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

ALEXANDER BACKHOE & DOZER

Verified · Lic. 10320
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

American Excavation, LLC

Verified · Lic. 14286
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Anglin Septic Services INC.

Verified · Lic. 12784
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Anthony Bowling Backhoe

Verified · Lic. 778
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Ashworth's Backhoe Service, LLC

Verified · Lic. 10416
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

B&B Construction

Verified · Lic. 14346
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Backroad Septic and Services LLC

Verified · Lic. 591
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Pumper · TN TDEC · verified 2026-06-25

Bagwell Waste LLC

Verified · Lic. 1026
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Pumper · TN TDEC · verified 2026-06-25

Benchmark Plumbing Inc.

Verified · Lic. 18064
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Binkley's Backhoe Service

Verified · Lic. 11766
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Boone Creek Plumbing

Verified · Lic. 18271
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Bradford's Land Management LLC

Verified · Lic. 19186
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Bruce’s Grading and Excavating, LLC

Verified · Lic. 13376
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Brushdawg Land Clearing LLC.

Verified · Lic. 19253
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Buddy E Tomlin jr

Verified · Lic. 11782
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

C&R Group General Contractors, LLC

Verified · Lic. 13606
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Campi Development

Verified · Lic. 14859
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Carbine Company Inc

Verified · Lic. 14867
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Carson Craig

Verified · Lic. 19625
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25

Carson Lewis

Verified · Lic. 19247
Franklin, TN
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Installer · TN TDEC · verified 2026-06-25
Get matched with verified pros

Tell us what you need. We'll contact several license-verified local companies and send back wait times, cost estimates, and availability — free, no obligation.

By submitting you agree we may share your request with local licensed contractors. No spam; we don't sell your info.

Septic System Installation in Williamson County — FAQ

What does a new septic system cost in Williamson 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 Williamson County are the biggest cost driver.

Do I need a permit to install a septic system in Williamson County?

Yes. Permits are issued by the Local authorized agent / county health department in Williamson 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.

Other services in Williamson County

Emergency Septic ServiceSeptic RepairSeptic Tank PumpingSeptic Inspection

Septic System Installation in nearby counties

Davidson CountyHamilton CountyKnox CountyRutherford CountyShelby County