State guide
Maryland
Maryland's onsite sewage program is state-directed by the Maryland Department of the Environment, but day-to-day approvals are delegated to county health departments and other local approving authorities. County pages in rural areas commonly describe official perc or soil-evaluation scheduling through the local environmental health office, while MDE maintains the statewide list of registered onsite wastewater professionals.
Checked against official sources on October 4, 2026. Rules and links change; confirm with the office listed before you act.
- Who regulates septic permits
- The Maryland Department of the Environment runs the statewide onsite systems program and delegates permitting and approvals to county health departments or other local approving authorities.
- Who can do the soil or perc test
- Maryland COMAR says the applicant conducts the soil tests, while county pages show local environmental health staff or sanitarians conducting or observing the official perc/soil evaluation; private designers, septic professionals, contractors, and engineers may prepare designs where county procedures require them, and statewide onsite wastewater service providers must be registered with MDE.
- Official septic permit page
- Official page →
- Licensed evaluators or designers
- Official page →
- State fee
- Not published by an official source we could verify. Ask the office.
Official resources in Maryland
State overview page for onsite sewage disposal systems, local authority links, and professional registration information.
Official MDE list of county health departments and local agencies that issue onsite sewage approvals.
MDE guidance page with site-evaluation application materials and report templates used by local authorities.
Board page explaining Maryland registration and licensing rules for individuals providing onsite wastewater services.
Official statewide list of registered individuals local permitting authorities reference for onsite wastewater services.
Key facts for Maryland
- MDE says its Onsite Systems Division provides technical assistance and direction to county health departments and local approving authorities.
- COMAR says the applicant shall conduct all soil tests at the depth and in the soil intended for the onsite sewage system.
- MDE says anyone performing any activity associated with onsite wastewater disposal must register with the State Board.
- Frederick County says the FCHD sanitarian conducts the official percolation test and records the results.
- Carroll County says the applicant must arrange for an excavator after filing the perc-test application and paying fees.
- Worcester County says septic plans must be submitted by qualified private-sector designers, including septic contractors, other septic professionals, or engineers.
County septic and soil-evaluation offices in Maryland
| County office | city | phone | Details |
|---|---|---|---|
| Allegany County Health Department - Environmental Health Allegany | Cumberland | (301) 759-5040 | Handles on-site well and septic programs; its page lists perc-test preparation help and a fee schedule including septic and perc fees. |
| Carroll County Health Department - Sewage Disposal Carroll | Westminster | 410-876-2152 | Local sewage-disposal page for septic oversight, with a separate perc-testing page explaining applications, excavators, and wet-weather testing. |
| Carroll County Health Department - Percolation Tests/Wet Weather Testing Carroll | Westminster | 410-876-1884 | Explains when wet-weather testing is open or closed and how applicants schedule perc tests. |
| Frederick County Health Department - Well and Septic Frederick | Frederick | 301-600-1726 | County well and septic program page for perc tests, soil evaluations, septic design review, and installation inspections. |
| Frederick County Health Department - Percolation Test Frederick | Frederick | Not published* | Explains the county's soil-evaluation and perc-test application steps, including the need for a backhoe operator. |
| St. Mary's County Health Department - Perc Testing St. Mary's | Not published* | (301) 475-4321 | County page for new-construction and repair perc testing, with application and Environmental Health Division contact details. |
| Worcester County Department of Environmental Programs - Soil Evaluations Worcester | Snow Hill | Not published* | County page for soil-evaluation procedures and suitability determinations for onsite sewage disposal systems. |
| Worcester County Department of Environmental Programs - Septic System Permitting Worcester | Snow Hill | 410-632-1220 | Explains Worcester's septic-permit review process and the county's requirement that plans be submitted by qualified private-sector designers. |
* Not published: the official page doesn't list it. Call the office to confirm before you rely on it.
What to do next
- Find your county on MDE's Local Approving Authorities page first; that local office controls perc scheduling and septic permit issuance.
- Ask the county what it requires for excavation, plat review, and seasonal testing windows before paying a contractor.
- If you hire a private designer or contractor, confirm the person appears on Maryland's registered onsite wastewater professionals list.
Not seeing your county office or county?
Not every county office publishes its rules online. Try these, in order:
- General Start with the statewide information above.
- Closest verified Nearest places where we have verified local data outside this state (distance from Maryland's population center, for comparison only):
- Department of Buildings Walk-in Center, District of Columbia · about 19 miles
- Department of Energy and Environment, District of Columbia · about 19 miles
- SGS Help Desk, District of Columbia · about 19 miles
- Call to confirm Ask the official office.MDE On-Site Systems Division
Website →Phone: (410) 537-3778 (as listed on that page, checked Oct 4, 2026)Your city or county office: Maryland Manual: county governments →Not sure who handles it locally? USAGov's free help line, 1-844-872-4681, or the Maryland page on USA.gov can point you to the right office. - Know the current info? Tell us with a link to the official page.