Service

Septic tank & drain field

Most of the residential lots we work on outside the Chattanooga sewer service area are on a septic system — and the system is the single most expensive infrastructure item on the property after the house…

Services  /  Septic tank & drain field

What's included

  • Site evaluation with the percolation test or soil-classifier evaluation
  • TDEC or Georgia Health Department permit filings
  • Tank excavation, set, and connection to the building sewer line
  • Drain field trenching sized to the perc rate and household load
  • Distribution box placement and leveling
  • Inspection coordination with the regulator at the required stages
  • Backfill, grading, and topsoil restoration over the system

Why permitting matters

Septic systems are not optional permit jobs. In Tennessee, on-site sewage falls under TDEC; in Georgia, under the county Health Department. The permit is tied to the site and the building, and inspectors verify the system at multiple stages — tank set, lateral lines, and final cover. We coordinate those inspections as part of the scope so the work isn't blocked by a missed call.

How sizing works

Drain field size is dictated by two numbers:

  1. The percolation rate of the soil (how fast water moves through it).
  2. The design flow for the household — typically calculated from the number of bedrooms.

Tighter clay soils need longer drain field lines because the soil can absorb less water per square foot. Sandier soils need less length. We design and trench to the rate that came back from the perk test — not to a guess.

Common situations we handle

  • New construction on a previously raw lot
  • Replacement of a failed system on a property that's outgrown its old field
  • Tank-only replacement when the lines are still serviceable
  • Lift station installations where the building sits below the drain field
  • Repair of broken or root-invaded lateral lines

Soil and site considerations in the Greater Chattanooga area

The red clays common in Catoosa and Walker County percolate slowly — perk rates of 60+ minutes per inch are routine. That doesn't mean the lot is unbuildable; it means the drain field needs to be longer or set in a sand-filter design. Lots along creek bottoms or with high seasonal water tables sometimes require mound systems or pressure-distribution designs. We work through these with the regulator before the work starts.

Meta

  • Meta title: Septic Tank & Drain Field Installation in Chattanooga, TN | L & S Excavation
  • Meta description: Septic tank, drain field, and on-site sewage excavation across Hamilton County, Catoosa, and the surrounding area. TDEC-permitted, soil-tested, built to last.

Recent work

Service areas

Available across the Greater Chattanooga area.

FAQs

Common questions, straight answers.

How long does a septic system installation take?

For a typical 3-bedroom residential system on a perked lot, excavation through cover is 2-4 working days. Add a day or two for inspection windows. Bad weather can push the schedule because we cannot trench in saturated soil.

Do you handle the percolation test?

We work with licensed soil scientists and TDEC-certified inspectors for the perk test. If a perk has already been done on the lot, we'll build to it; if not, we'll get one scheduled before the design is final.

What's the difference between a conventional and a low-pressure drain field?

A conventional drain field uses gravity to distribute effluent through perforated pipe in stone-bedded trenches. A low-pressure dosing (LPD) system uses a pump and pressurized lateral lines to spread effluent evenly across the field — useful on slow-perking soils. The choice is driven by the perk rate, the slope, and what the regulator approves.

How deep does a septic line go?

Building sewer lines are typically buried 18-24 inches with frost-protection coverage above. Drain field laterals sit shallower — usually 24-36 inches to the bottom of the trench — so the biology in the topsoil layer can do its work.

Can the drain field go under a driveway?

No. Compaction over a drain field destroys the air gaps the soil biology needs and crushes the lateral pipe. Drain fields need to stay under vegetated, uncompacted ground.

Do you do pump-outs or maintenance?

We focus on installation and replacement. For regular pump-outs we'll refer you to a maintenance specialist in the area.

Ready to break ground?

Let's talk about your site.

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