Aerobic / ATU Septic System Cost in Connecticut
Estimated 2026 installed range: $10,400 – $23,400
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Statewide cost drivers here are freeze depth, bedrock and older housing stock. Locally, older homes often need full replacement plus Title V compliance upgrades. That is why a aerobic / atu system in Connecticut can land well above or below the national range of $8,000–$18,000.
All system types in Connecticut
| System | Low | High |
|---|---|---|
| Conventional | $4,600 | $10,400 |
| Chamber | $6,500 | $14,300 |
| Aerobic / ATU | $10,400 | $23,400 |
| Mound | $13,000 | $28,600 |
| Sand filter | $10,400 | $20,800 |
What aerobic / atu systems are for
Aerobic treatment units add oxygen to break down waste faster. They are used on tight or wet lots, require electricity, and need periodic maintenance.
Related pages
All septic costs in Connecticut · Aerobic / ATU system overview