In Connecticut, onsite wastewater (septic) systems are regulated by Connecticut Department of Public Health (DPH), Environmental Health Section - Environmental Engineering Program, which sets the statewide code; some counties are delegated to issue permits and inspect locally, others are handled directly by the state agency. Installing, replacing or repairing a septic system here means, in sequence: a site and soil evaluation, a design, a permit application, an inspection while the system is open, and a final as-built record once it is approved.
The state-level regulator is Connecticut Department of Public Health (DPH), Environmental Health Section - Environmental Engineering Program (official program page). Systems with design flows of 10,000 gallons per day (gpd) or less are permitted by the local Director of Health; plans for systems between 2,000-10,000 gpd must additionally be approved by CT DPH; systems exceeding 10,000 gpd and alternative treatment systems are permitted by the CT Department of Energy and Environmental Protection (DEEP).
The statewide onsite-wastewater code is cited as Regulations of Connecticut State Agencies Sections 19-13-B100a and 19-13-B103 (Public Health Code), with associated Technical Standards for Subsurface Sewage Disposal Systems. We link the agency's own page above rather than restating specific numeric requirements from it, since those change by rule revision and by local amendment.
The order of operations is broadly consistent across the country, even though the specific numbers in each step vary by state and often by county. None of the figures below are specific to Connecticut; treat this as the shape of the process, and get the actual numbers from the agency linked above or from the county office.
| Design | Where required by the local director of health, plans must be prepared by a Professional Engineer registered in Connecticut; for standard small systems a state-licensed installer may prepare plans depending on local health department requirements. |
|---|---|
| Installation | CT DPH-licensed Subsurface Sewage Disposal System Installer (exam-based license administered by DPH); a separate license also exists for septic tank cleaners. |
Septic records in Connecticut are generally held by the county or local health jurisdiction that issued the permit, not by the state agency, and are released under the state's public records law. We have not logged the specific statute name and response deadline for Connecticut yet; check with the county office listed on its records page below, or with Connecticut Department of Public Health (DPH), Environmental Health Section - Environmental Engineering Program.
We hold 13,564 septic records across 1 of 9 Connecticut counties. Each county page below shows exactly where its records are kept and how many we hold.
| County | Records held |
|---|---|
| Northeastern Connecticut | 13,564 |
Full Connecticut county-by-county index · Open the parcel map
Connecticut Department of Public Health (DPH), Environmental Health Section - Environmental Engineering Program. Systems with design flows of 10,000 gallons per day (gpd) or less are permitted by the local Director of Health; plans for systems between 2,000-10,000 gpd must additionally be approved by CT DPH; systems exceeding 10,000 gpd and alternative treatment systems are permitted by the CT Department of Energy and Environmental Protection (DEEP).
The sequence is a site and soil evaluation, a design sized from the evaluation and (under most state codes) bedroom count, a permit application, an inspection before backfill, and a final as-built filed once the system is approved. Exact numeric requirements are set by the agency's own code, not restated here.
CT DPH-licensed Subsurface Sewage Disposal System Installer (exam-based license administered by DPH); a separate license also exists for septic tank cleaners.
Septic records are generally held by the county or district health office that issued the permit. See our county-by-county Connecticut index for the specific office and portal in each county.
Regulatory information on this page was researched against official state agency sources and last verified 2026-08-31. It is informational only: the agency linked above is authoritative, and requirements can change. We are not lawyers, not a government body, and not affiliated with, licensed or certified by any agency named on this page.