Ohio EPA's construction stormwater permit, the one-acre trigger, and the county and township rules that catch landowners off guard.
Ohio''s framework looks a lot like Indiana''s, because both sit under the same federal Clean Water Act structure. The details and the agencies differ.
General orientation, not legal advice. Confirm with the agencies below for your specific site.
The one-acre threshold
Ohio EPA administers the NPDES Construction General Permit (CGP) for construction activity disturbing one acre or more. The current general permit is OHC000006.
As in Indiana, smaller sites are pulled in when they are part of a larger common plan of development or sale.
Coverage requires filing a Notice of Intent and having a stormwater pollution prevention plan in place before disturbance begins.
Contact: Ohio EPA, Division of Surface Water — Stormwater Program.
Exemptions
The federal framework exempts routine agricultural operations and silvicultural (forestry) activity. As in Indiana, the exemptions are narrower than people assume:
- Ordinary farming — plowing, planting, cultivating, harvesting — is generally exempt
- Constructing agricultural infrastructure such as buildings, roads, ponds, and lagoons is generally not exempt
- Forestry harvesting is treated differently from clearing done in preparation for development
If you are clearing because something is going to be built, plan on the permit applying.
Local layers in Ohio
County engineer. Road approaches and culverts onto county roads. Specifications for pipe size, invert, width, and sight distance. On a state route, contact the ODOT district office.
Soil and Water Conservation District (SWCD). Ohio SWCDs are heavily involved in erosion and sediment control review, and in many counties they administer or assist with local stormwater requirements. They are also genuinely helpful on conservation questions and often free.
County or township zoning. Ohio has meaningful township-level zoning in many areas, which surprises people used to county-only structures. Check both.
Floodplain administrator. Every participating community has one. Work in a mapped floodplain requires review.
Ditch petitions and county ditch maintenance. Ohio county ditch systems have their own procedures and protected corridors. The county engineer''s office is the starting point.
Open burning. Ohio EPA regulates open burning, with different rules inside and outside restricted areas — generally more restrictive near municipalities. Check current rules and any active burn ban before planning to burn cleared material.
Utility locates
Call OHIO811 (811) before digging. Free and required by law. Applies to excavation, grubbing, post holes, and culvert work.
Wetlands and streams
Ohio EPA administers Section 401 water quality certification and has its own isolated wetland permitting program, alongside federal Army Corps jurisdiction under Section 404. Ohio''s isolated wetland rules mean some wet areas are regulated at the state level even where federal jurisdiction does not reach.
If your ground has wet areas, a wetland determination before clearing is far cheaper than an enforcement action after.
Practical sequence
- Call the county engineer and the zoning authority — county and township
- Call the SWCD; they will often walk the site
- Total your disturbed acreage, including access and staging areas
- If one acre or more, begin the Ohio EPA CGP process early
- Call 811 before digging
- Erosion controls in before earthwork
The shortcut
Your county SWCD is the best single first call in Ohio. They know the local requirements, they know who administers what, and helping landowners get this right is their actual job.
Clearing property in Ohio? We work within Ohio EPA and county requirements.
Sources: Ohio EPA Stormwater Program · Ohio EPA Construction General Permit OHC000006 · US EPA — Construction General Permit FAQ
