Animal feeding operations are regulated by the state to protect local waterways, the Chesapeake Bay, and drinking water from nutrient and sediment pollution. These operations are essential to Maryland’s agricultural economy, but must meet environmental standards that safeguard public health and natural resources. The types of facilities fall into three main categories:
Animal Feeding Operation (AFO):
A facility where animals are confined and fed for a total of 45 days or more in any 12-month period, and where vegetation is not sustained during the normal growing season.
Concentrated Animal Feeding Operation (CAFO):
A larger AFO that meets specific size thresholds set by the U.S. Environmental Protection Agency (EPA) and MDE. CAFOs have greater potential to discharge pollutants and are therefore subject to more stringent requirements under the Clean Water Act.
Maryland Animal Feeding Operation (MAFO):
An operation that does not meet the federal size definition of a CAFO but has similar potential for nutrient runoff or water quality impacts. MAFOs are regulated by the State of Maryland and must obtain permit coverage similar to CAFOs.
Together, these designations apply to all farms handling large volumes of manure or wastewater to manage those materials responsibly and consistently.
Permit Coverage and Compliance
Animal feeding facilities are regulated through a general discharge permit. Farms that meet the criteria must
apply for coverage by submitting a Notice of Intent (NOI) and a Nutrient Management Plan that demonstrate how manure and processed wastewater are properly stored, handled, and applied to land. This permit prevents pollution of waterways by requiring specific operating conditions for large poultry houses, dairy farms, cattle operations and other agricultural operations that confine animals.
MDE is required to post Notices of Intent and Required Plans for 30 days prior to a CAFO being registered under the General Discharge Permit. The public may provide comments and request a public hearing within this time. All CAFOs on public notice can be found
here.
- Permit requirements include:
- Manure and wastewater are managed to prevent nutrient runoff.
- Storage structures are properly maintained.
- Land application follows approved agronomic rates.
- Stormwater and wash water are controlled to avoid discharge.
Final 25AF General Discharge Permit For Animal Feeding Operations (Documents)
The deadline to submit a petition for judicial review is June 8, 2026.
Draft 25AF General Discharge Permit For Animal Feeding Operations
Fees and Reporting
State law requires us to collect annual fees for animal feeding operations. After receiving an application for permit coverage, we send an invoice to the applicant. Fees must be paid each year by the anniversary of the permit’s effective date. Check the permit to determine if you are a small, medium or large facility. Amounts are based on the size of the operation:
Facility Type |
Total House Capacity |
Fee |
New or expanding | 350,000 sq ft or more | $2,000 (one-time fee) |
Existing | 350,000 sq ft or more | $1,200 (annual) |
Small | Less than 350,000 | $120 |
Medium | Less than 350,000 | $600
|
Large | Less than 350,000 | $1,200
|
All applicants must submit an annual implementation report summarizing their nutrient management activities and best management practices for the previous year.
Environmental Justice and Public Access
Maryland’s environmental justice law requires applicants to include an environmental justice screening
score. This score helps identify whether a farm is located in or near an overburdened community and ensures that environmental decisions are made transparently and equitably.
Documents
