How Much For New Drain Fields Per Foot

Answered by LCD: I presume this is after the tank has been pumped that this is still happening, so it is not just a frothed-up tank with the outlet blocked by floatables.

Backflow does not necessarily mean the field is dead - though if around 15-20 years old, especially if not in free-draining sandy or gravelly soil, it well could be - though in good conditions without excess garbage going down the drain and using leachfield safe toilet paper, can commonly go 20-30 years, or even much more if number of residents is significantly less than design capacity. I have seen fields over 100 years old still working well, in free-draining soil and proper design.

Backflow can be caused by a blocked grease/debris screen at the outlet, sludged-in tank outlet pipe or junction box or manifold (the pipe that the individual leach field pipes branch off of), or grease and paper or root blockage in the leach field pipes themselves which can sometimes (with some field designs) be routed or jetted out to give 5 years or so more life, etc.

I always recommend an inspection by a certified septic system inspector/cleaning company, because commonly $250-1000 worth of inspection, repair, and cleaning (usually by jetting and maybe a chemical treatment) can save you many thousands.

New leach field - and the typically $5-15/per LF for leach pipe installation really means nothing because different fields have different pipe spacing for different soils, generally if the field is "saturated" you either need a totally new leach field in an adjacent area for commonly $2,500 - $5,000, or significant (commonly up to 4-8 feet deep) removal and trucking off of the exissting leach field and replacement with suitable soil for commonly more in the $4,000-8,000 range - or in poor soil conditions or where there is not room for a new fieldor the existing soil does not meet current requirements, sometimes an above-ground "mound" system - which can commonly run $10,000-30,000 depending on size and area and native soil conditons.

These ballpark numbers are for typical simple rectangular gravity flow leach field, without any lift pump, and without doing anything to the existing tank other than pumping it. Definitely get some bids - and for a new field you will need, in almost all areas, a test/design and inspection by a civil engineer, who can also help you with recommendations on possible bidders.

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