If you plan to build a retaining wall, regrade part of your yard, or change drainage in Maryland, you may need permits before work starts. In many cases, review is triggered when you disturb 5,000 sq. ft. or more, move 100 cu. yd. or more of soil, or build a wall over local height limits like 2 ft., 3 ft., or 48 in., depending on the county.

Here’s the short version:

• Large grading jobs often need erosion and sediment control review.
• Retaining walls may need a permit based on height, added load, or location near a property line.
• Drainage changes can trigger review even on smaller jobs.
• County rules differ, so the right office and permit path depend on where you live.
• Plans matter: most applications need a site plan, wall details, and drainage notes.
• Inspections are part of the job, and unapproved field changes can cause delays or failed finals.

A few numbers put this in perspective:

• 5,000 sq. ft. is about a 70 ft. × 70 ft. yard area
• 100 cu. yd. is about 7 to 10 dump-truck loads
• Regrading 5,000 sq. ft. by just 1 ft. can create about 185 cu. yd. of cut or fill

If I were checking a project fast, I’d focus on three things first:

1. How much land will be disturbed
2. How tall the wall will be
3. Whether runoff will move to a new place

The main point: I would not judge a project by wall height alone. In Maryland, grading volume, drainage changes, surcharge loads, and county rules can all change the permit path.

The rest of the article walks through those triggers, the county review setup, the paperwork, and the inspection steps in plain English.

BC Builds: What to Know Before Applying for a Permit in Baltimore County

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Step 1: Check whether your project triggers permit review

Before you dig, check your project against Maryland’s main permit triggers. Focus on three things: land disturbance, wall height, and drainage changes.

Land disturbance, grading, and erosion control thresholds

Maryland’s statewide erosion and sediment control rules generally require an erosion and sediment control plan when a project disturbs 5,000 sq ft or more of land area or involves 100 cu yd or more of soil.^[10][11][14] Baltimore, Washington, Carroll, and Prince George’s counties use the same thresholds for grading review.^{[9][12][13][15][16]}

Here’s what that looks like on the ground. 100 cu yd is roughly 7 to 10 full dump-truck loads of soil. And 5,000 sq ft is about a 70 ft × 70 ft section of yard. If your project is anywhere near either limit, it’s worth measuring instead of guessing.

A small grade change can add up fast. Regrading a 5,000 sq ft area by just 1 ft of average depth produces about 185 cu yd of cut or fill, which is already above the 100 cu yd trigger by itself.^[10][12][15]

In Prince George’s County, drainage changes can wipe out the small-project exemption even if you stay below the size thresholds.^[20] If your grading changes where water flows, it’s safer to assume review applies.

Retaining wall height and structural conditions that require permits

Montgomery and Baltimore counties require permits for walls over 3 ft. Prince George’s County uses 2 ft.^{[1][4][5][21][22]}

Height isn’t the only thing that matters. Some walls need permits even when they’re shorter.

That usually happens when the wall supports a driveway, parking pad, foundation, or another structure. In that case, the wall carries added load, which means extra lateral pressure beyond normal soil weight. Montgomery County is direct on this point: any wall with added load requires a permit.^[4]

The same issue can come up when a wall sits on or near a property line, or when it’s part of a tiered system. Tiered walls may be treated as one structure.^[4][7]

Drainage changes that can add extra review

Drainage work can trigger review even when grading stays under the main thresholds. French drains, swales, dry riverbeds, and outfalls all redirect runoff. If that water reaches a neighboring lot or ties into a storm drain system, local drainage rules often require review.^[17][18]

Montgomery County’s drainage control rules prohibit grading that causes water to pond on adjacent property. They also require finished grades to drain lawns and keep water away from foundations.^[17] On top of that, Montgomery County requires approved drainage systems to handle 1.5 inches of rain in 24 hours.^[18]

If your soil retention project includes drainage work, build that into your permit check from the start.

If any of these triggers apply, the next move is to match the project to the correct state or local approving office.

Step 2: Know which Maryland agency or local office approves your work

In Maryland, permit authority is split between the state and local governments. The state sets the erosion and sediment control rules through Environment Article Title 4 and COMAR 26.17.01, but in most cases, local agencies handle the actual review and approval process for home projects.^{[23][24][10][14]}

That usually means a county office, city department, or soil conservation district will review your residential plans, issue the approval, and inspect the work. So before you get too far, pin down the local office that will handle your permit.

County and city permit paths for walls, grading, and drainage

Most counties handle retaining walls, grading, and drainage through local permit systems that follow state rules.

But here’s the catch: the process isn’t the same everywhere.

Some counties bundle these reviews into one application. Others split them up. Prince George’s County, for instance, requires both a grading permit and a separate retaining wall building permit. So if your wall is over 2 feet, a grading permit by itself won’t cover it.^[22][27] Carroll County takes a different route. Its grading permits go through the Bureau of Resource Management, while wall permits are handled by a separate permits and inspections office.^[28][29]

County-by-county comparison for central Maryland homeowners

Use this table to see where your county sends wall, grading, and drainage reviews.

Once you’ve matched your county to the right review path, you can pull together the plans and reports that office wants.

Step 3: Gather the plans and documents your permit application needs

Once you know which office will review your project, pull together the paperwork before you apply. In Maryland, most permit offices look for the same core set of documents: a site plan, wall design, and drainage details. That package shows the project fits Maryland’s permit rules.

Site plan, measurements, and property details

Submit a scaled site plan that shows the property lines, the wall or graded area, nearby structures, disturbed area, grading limits, and final drainage direction.^[31] Reviewers use this drawing to check the layout, where water will go, and how close the work sits to structures and property lines.

Engineered wall plans and supporting calculations

If a wall goes over local height limits, carries surcharge loads, or uses tiered construction, you’ll usually need engineered drawings and, in some cases, a geotechnical report.^[31]

Homeowners may pull permits for a primary residence, but stamped drawings are still required when the project meets height or surcharge thresholds.^[31]

Erosion control and drainage documentation

After the wall design, show how the project will deal with water.

Submit drainage details that show how the wall will relieve pressure and keep runoff on site.^[31] Include a perforated drain pipe at the wall base with a minimum slope of 1%, a gravel drainage zone of at least 12 inches, and filter fabric.^[31] Show the outlet location too, and make sure runoff stays off neighboring property.^[31]

Step 4: Apply, build, and close out your permit correctly

Once your paperwork is set, the permit process usually follows a clear path: submit, review, build, and closeout. In practice, it can get a bit messier. Review comments, plan updates, and inspections often add a few more turns, so it helps to know the road before you start.

Submitting applications and responding to review comments

Send your completed permit package through your local permit portal or permit office. Fees and review timelines depend on the jurisdiction and the scope of your project. Homeowners can apply as owner-builders, but they still carry the responsibility for code compliance ^[31].

If the reviewer sends comments back, answer every one of them. Then resubmit the corrected plans. Skipping a comment or leaving a plan note unaddressed can slow things down fast.

Inspections, field changes, and final approval

Post the approved permit at the job site before any work starts ^[31]. From there, build to the approved plans. If something changes in the field, get it approved before moving ahead.

That part matters more than many people think. Changes to wall height, location, or drainage routing can cause a failed final inspection if they weren’t approved first ^[31].

After permit approval, the build phase turns into a set of required inspections. Schedule each one at least 24–48 hours ahead ^[31]. There are four main stages:

Do not backfill or cover any component until it has passed its inspection.

Keep sediment controls in place through the final sign-off.

Working with a qualified Maryland contractor

A contractor who knows Maryland permit sequencing can help keep the job on track and lined up with the approved plans. For homeowners in central Maryland, Pro Landscapes MD can handle retaining walls, grading, and drainage work that stays aligned with permit requirements.

Conclusion: Key permit checks before starting soil retention work

Use this check before you submit plans or break ground.

If your project will disturb 5,000 square feet or more or move 100 cubic yards or more of soil, Maryland’s erosion and sediment control rules will generally apply. Your county may set extra triggers on top of that.^[10][32][19]

Wall size matters too. If the wall goes past local height limits, or if it supports a surcharge load like a driveway or sloped backfill, the project may need permits even if the wall doesn’t look that large at first glance.^[4][3][1]

Once you’ve confirmed the triggers, find the right reviewing office. Erosion control, grading, and retaining wall permits don’t always land with the same department, and the approval path can change from one county to the next.

From there, make sure your application is built on clean measurements. Accurate site dimensions and drainage notes can save you from plan revisions and back-and-forth delays.

Maryland does enforce these rules. Starting work without approval can lead to stop-work orders, fines, and expensive rework.

A little planning up front lowers risk. It helps keep the job compliant, protects drainage performance, and cuts the odds of enforcement action or structural trouble later on. For central Maryland projects, Pro Landscapes MD handles retaining walls, grading, and drainage work across Howard, Montgomery, Carroll, Frederick, Prince George’s, and Baltimore counties.

FAQs

Do I need a permit for a small retaining wall?

It depends on the wall’s height, the soil load behind it, and the rules in your area. In many places, once a wall passes a set height, officials treat it as a structural element and want it reviewed.

You may also need a permit if the job disturbs 5,000 square feet or more, moves more than 100 cubic yards of fill, or takes place in a protected area such as a Chesapeake Bay Critical Area.

How do I calculate disturbed area and soil volume?

Measure the total disturbed area where soil will be cleared, graded, or otherwise changed. This includes new structures, driveways, patios, and even staging areas. If your project disturbs 5,000 square feet or more, it will generally need permit review.

For soil volume, multiply the excavation or fill area by the average depth. That gives you cubic feet. Then divide by 27 to convert the number into cubic yards. If you’re moving more than 100 cubic yards of fill, that will typically require an erosion control permit.

Which county office handles my wall or grading permit?

In Maryland, wall and grading permit rules vary by jurisdiction. That means the office you need can change depending on the county or city.

Your best move is to contact your local county or municipal permitting department and confirm who handles the application.

For example, Baltimore County uses a dedicated grading permit portal. Prince George’s County sends erosion and sediment control plan approvals through the local Soil Conservation District. And if your property falls within a municipal boundary, there may be extra permit steps on top of the county process.

Because of that, it’s smart to verify the process with the local office before you file anything.

Related Blog Posts

• Grading vs. Retaining Walls: Erosion Control Options
• Retaining Walls for Flood Prevention
• Retaining Wall Permit Requirements by County
• 4 Retaining Wall Code Triggers In Maryland