Grease Trap Regulations in Maryland

Overview

Maryland food businesses must follow FOG pretreatment rules. The Maryland Department of the Environment (MDE) Pretreatment Program oversees all approved local programs across the state. Most enforcement happens at the county or city utility level.

FOG matters here because sewage overflows hurt streams, rivers, and the Chesapeake Bay. That gives FOG rules extra weight in Maryland.

Governing Authorities

At the state level, the MDE Pretreatment Program oversees all approved local pretreatment programs. The program follows the EPA national pretreatment framework. Local enforcement goes to county and city utilities that run approved pretreatment programs.

Major enforcement bodies include:

• Baltimore City Department of Public Works: Runs the FOG program for all food businesses inside Baltimore City.
• Washington Suburban Sanitary Commission (WSSC Water): Covers nearly all of Montgomery and Prince George's Counties, except the Cities of Rockville and Poolesville.
• Anne Arundel County Department of Public Works: Runs the county pretreatment and FOG program.
• Baltimore County Bureau of Utilities: Enforces FOG rules in Baltimore County.
• Howard County Bureau of Utilities: Runs the pretreatment program for Howard County.

Key Requirements

Maryland FOG rules vary by county. They share common standards for trap install, cleaning, and records.

Interceptor Sizing and Installation

• Anne Arundel County requires any business that puts FOG-laden wastewater into county sewers to install at least a 500 gallon grease interceptor.
• Some counties make all FOG fixtures (sinks, dishwashers, mop sinks, floor drains) tie into a 2,000-gallon outdoor underground tank.
• Others let only sinks and dishwashers tie into an indoor unit near the source.

Cleaning Frequency

• Baltimore City requires grease trap cleaning at least every 90 days. Many spots need more frequent service based on volume.
• WSSC Water requires outdoor traps to be pumped dry and cleaned every month.
• The 25% rule says traps must be cleaned before grease and solids hit 25% of capacity. This applies no matter how long since the last service.

Record-Keeping and Manifests

• Keep cleaning and service records for at least three years. Show them when an inspector asks.
• Pumping must be done by a WSSC Water permitted grease hauler. Each service needs a manifest.
• WSSC rules say all liquids, solids, and grease must come out during cleaning.
• Haulers must file the manifest in WSSC's online system within 2 business days of pump-out.

Permit Requirements

• WSSC Water requires every food business to get a FOG Wastewater Discharge Permit.
• Starting July 1, 2025, the annual fee is $745 for a Full Permit FSE and $220 for a BMP Permit FSE.
• All food businesses get yearly inspections. They may be checked any time after a complaint or sewer block.

Fines and Enforcement

Maryland counties run active enforcement programs with set penalty levels.

Baltimore City

• Ongoing violations can bring fines starting at $1,000 and rising to $10,000 or more for serious or repeat issues.
• First-time violations usually get a written warning with a fix-by deadline.
• In bad cases, the city can issue emergency orders, pause business operations, or pull permits.

WSSC Water (Montgomery and Prince George's Counties)

• Breaking any condition of an FSE permit can bring fines up to $1,000 or shut-off of water and sewer service.

Baltimore County

• FOG and pretreatment violations are charged as civil penalties per day under the Baltimore County Code. The Bureau of Utilities sets the exact amount and how it grows.

Infrastructure Liability

Businesses may have to pay for damage to city sewers caused by bad FOG management. This can mean costs well beyond the fines.

Major City FOG Programs

Baltimore City

All food businesses that send (or could send) FOG into the city sewer must follow the FOG Program. The Baltimore City Department of Public Works runs the program and does routine inspections. Since 2002, the city has worked under a court-ordered consent decree with the EPA and MDE. The decree aims to cut untreated sewage and meet the Clean Water Act. Baltimore requires quarterly cleaning at minimum, with strict use of the 25% rule. Businesses must keep three-year records and provide manifests from licensed haulers.

Montgomery and Prince George's Counties (WSSC Water)

WSSC Water serves nearly all of Montgomery and Prince George's Counties. It runs one of the most detailed FOG programs in the country. By mid-2012, about 4,600 food businesses held FOG permits in the two counties. The commission requires every food business to get an electronic FOG permit through its ePermitting system. WSSC requires food businesses to install and maintain grease traps. The goal is to cut sewer overflows caused by grease blockages. Monthly cleaning is required for outdoor traps. Manual indoor traps need daily cleaning. As of 2026, annual permit fees are $745 for full permits.

Anne Arundel County

Anne Arundel County Public Works enforces strict trap sizing rules. Under Anne Arundel County Code, any business that puts FOG-laden wastewater into county sewers must install at least a 500 gallon grease interceptor. The county pretreatment program requires all commercial businesses to file permits and follow regular inspections. County inspectors check install, sizing, and upkeep of grease systems.

Howard County

Howard County Bureau of Utilities runs FOG compliance with a focus on Chesapeake Bay protection. Sewage overflows are a public health risk and a major source of pollution to local streams, rivers, and the Bay. The county offers home cooking oil recycling at Alpha Ridge Landfill. It enforces commercial FOG standards through its pretreatment program. Food businesses must follow maker cleaning advice and keep records of all grease trap service.

Frequently Asked Questions

How often must I clean my grease trap in Maryland?

Cleaning timing depends on your county and trap type. Baltimore City requires cleaning at least every 90 days for outdoor traps. WSSC Water (Montgomery and Prince George's Counties) requires monthly cleaning for outdoor traps and daily cleaning for manual indoor traps. All counties enforce the 25% rule. That means cleaning whenever grease and solids hit 25% of capacity, no matter the time. Busy restaurants serving fried food often need monthly service to stay compliant.

What records must I keep for FOG compliance?

Maryland food businesses must keep records for at least three years. Required papers include licensed hauler manifests showing date, time, volume, and hauler details for each pump-out. You also need cleaning logs and inspection reports. WSSC Water requires online manifest filing within two business days of service. Records must stay on-site and ready for surprise inspections by utility staff. Missing or partial records can lead to fines right away.

Can I clean my own grease trap or must I hire a licensed hauler?

Rules vary by area and trap size. Baltimore businesses can clean smaller under-sink units in-house with the right gear, trained staff, and proper waste disposal. WSSC Water requires pumping by WSSC-permitted haulers who file online manifests. Larger outdoor traps usually need licensed haulers with vacuum trucks and disposal permits. Most areas require waste to go to approved sites. That makes licensed haulers the simple choice for staying compliant.

Find Grease Trap Service in Maryland

Our directory lists 27 certified grease trap service providers across Maryland. These licensed pros know state and local FOG rules. They can help you meet MDE, Baltimore City, WSSC Water, Anne Arundel County, and other local rules. From routine cleaning and emergency pump-outs to install and repair, qualified contractors keep your business in line on cleaning schedules, manifests, and records. Find Maryland grease trap service providers in your area to avoid costly fines and damage liability.