Drain Field Replacement Cost
What a new leach field costs by system type, and why mound systems cost several times more than a conventional field.
Typical prices
HomeGuide puts a typical drain field replacement at $3,000 to $15,000, averaging about $7,900. A conventional gravel field alone runs $2,000 to $6,000, while mound fields, needed where soil is shallow or the water table is high, cost $10,000 to $20,000 (HomeGuide and HomeAdvisor). Repair or rejuvenation is usually $1,000 to $5,000 (HomeGuide).
By system type
| System | Typical cost | Source |
|---|---|---|
| Conventional gravel trench (field only) | $2,000 to $6,000 | HomeGuide |
| Chamber (gravel-less) field | $4,000 to $12,000 | theseptic.guide; HomeAdvisor chamber system $5,000 to $12,000 |
| Drip distribution | $8,000 to $18,000 | HomeAdvisor; theseptic.guide |
| Aerobic (ATU) field | $7,000 to $10,000 | HomeGuide; full ATU systems $10,000 to $20,000 (HomeAdvisor) or more |
| Mound | $10,000 to $20,000 | HomeGuide; HomeAdvisor avg $15,000 |
| Sand filter | $7,000 to $15,000 | theseptic.guide |
Why bedrooms matter
Health departments size drain fields by design flow, which most state rules base on the number of bedrooms. More bedrooms means more trench, more media and more excavation. Your county health department can tell you the local sizing rule.
Hidden costs
Budget for a perc test and engineered design, permit fees, tank pumping, removal of the failed field if it must be reused, and restoring the lawn or driveway the excavator crosses.
Sources
Sources: HomeGuide, Drain/Leach Field Replacement Cost (Dec 22, 2025); Angi, How Much Do New Drain Fields Cost? (Jul 8, 2026); HomeAdvisor, Septic System Installation Cost (Jun 20, 2026); theseptic.guide, Drainfield Replacement Cost (Mar 2026, secondary); Angi, Septic Tank Pumping Cost (Jul 9, 2026); EPA, How to Care for Your Septic System. Retrieved Oct 11–13, 2026.
Prices are published US ranges from the sources listed on each page; anything we calculated ourselves is labeled as an estimate. Get at least three written, itemized local quotes. Run the estimator to build your own range.