ABSOLUTE SEPTIC
Verified · Lic. 9043Clayton, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
Johnston County, NC · Septic System Installation
Septic System Installation in Johnston County
A new or replacement system in Johnston 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 Johnston County
Local ground is the deciding factor in Johnston County: Meeting the required separation to the seasonal high water table is the central challenge; many lots need imported fill, raised systems, or simply don't qualify without engineering. And the rules here matter — strict separation-to-seasonal-high-water-table drives heavy use of fill/mound and low-pressure pipe systems, 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 Johnston County
License-verified contractors (active state license) are listed first.
ADAMS SOIL CONSULTING
Verified · NC NCOWCICBMiddlesex, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Inspector · NC NCOWCICB · verified 2026-06-25
ADVANCED QUALITY INSPECTIONS
Verified · NC NCOWCICBClayton, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Inspector · NC NCOWCICB · verified 2026-06-25
AGUSTIN AVILA CONSTRUCTION
Verified · Lic. 9428Clayton, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
ALONSO'S CONSTRUCTION COMPANY LLC
Verified · Lic. 14963Smithfield, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
ALPHA CONTRACTING LLC
Verified · Lic. 11710Garner, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level IV) · NC NCOWCICB · verified 2026-06-25
ALPHA PLUMBING & SERVICES LLC
Verified · Lic. 9637Four Oaks, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
AMERICAN ENVIRONMENTAL & EXCAVATION
Verified · Lic. 11142Clayton, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
ASC CONSTRUCTIN LLC
Verified · Lic. 11998Four Oaks, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
ASHLEY LANGDON
Verified · Lic. 11977Angier, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
AVILA CONSTRUCTION LLC
Verified · Lic. 1917Smithfield, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
BATTEN'S BACKHOE SERVICE INC
Verified · Lic. 2682Princeton, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level IV) · NC NCOWCICB · verified 2026-06-25
BEMCO
Verified · Lic. 7147Benson, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level IV) · NC NCOWCICB · verified 2026-06-25
BEN'S PLUMBING & SEPTIC INC
Verified · Lic. 6495Wendell, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Inspector (Level IV) · NC NCOWCICB · verified 2026-06-25
BIGGS SEPTIC & SEWER SERVICES
Verified · Lic. 11662Garner, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
BOSWELLS LAWN SERVICE
Verified · Lic. 15090Four Oaks, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
BRYAN LOPEZ CAZARIN
Verified · Lic. 14654Benson, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
C C NORRIS ENTERPRISES
Verified · Lic. 11631Benson, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level IV) · NC NCOWCICB · verified 2026-06-25
CAPITOL CITY CLEARING
Verified · Lic. 15207Clayton, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
CAPPS PLUMBING COMPANY INC
Verified · Lic. 14741Four Oaks, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
CARROLL CONSTRUCTION HOMES
Verified · Lic. 5374Willow Spring, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Inspector (Level IV) · NC NCOWCICB · verified 2026-06-25
CHARLES HARDEE GRADING CO
Verified · Lic. 3623Benson, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
CHOSEN HOME INSPECTIONS INC
Verified · NC NCOWCICBRaleigh, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Inspector · NC NCOWCICB · verified 2026-06-25
CKB SITE SOLUTIONS LLC
Verified · Lic. 15072Dunn, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
COTY LEWIS
Verified · Lic. 14652Four Oaks, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
COX HAULING & GRADING LLC
Verified · Lic. 11860Four Oaks, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level IV) · NC NCOWCICB · verified 2026-06-25
DBA ABEL SEPTIC TANK CLEANING
Verified · Lic. 7012Smithfield, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Inspector (Level II) · NC NCOWCICB · verified 2026-06-25
DELL ADAMS
Verified · Lic. 3855Benson, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
Inspector (Level IV) · NC NCOWCICB · verified 2026-06-25
DIAMANTES CONSTRUCTION LLC
Verified · Lic. 11252Clayton, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
DOS BROS SEPTIC SERVICE
Verified · Lic. 14408Middlesex, NC
Septic Tank PumpingSeptic RepairSeptic InspectionSeptic System Installation
On-Site Wastewater Contractor (Level II) · NC NCOWCICB · verified 2026-06-25
Septic System Installation in Johnston County — FAQ
What does a new septic system cost in Johnston 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 Johnston County are the biggest cost driver.
Do I need a permit to install a septic system in Johnston County?
Yes. Permits are issued by the Local authorized agent / county health department in Johnston County, under North Carolina Department of Health and Human Services (NC DHHS), Division of Public Health — Environmental Health Section, On-Site Water Protection Branch (OSWP)., 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.