Guideline No. 45 – Retaining Walls

An Exterior Alteration Application is required for all retaining walls. Retaining walls and rock walls require thought and planning just like any other building project.  Soil properties, wall height, wall type or function, drainage surcharge loads, adjacent grading, etc. must be taken into consideration.

Application Requirements

Applications must include:

  • Plot/plat plan with location of retaining walls.

Note: Applications without a diagramed plot/plat plan will not be accepted.

  • Wall dimensions i.e. height, width, depth.
  • List of materials and color, (brochure or sample if applicable).
  • Grading diagram.
  • Drainage diagram.
  • Complete cross-sectional drawing of wall to scale.
  • Elevation view from the low grade side of wall drawn to scale.


Your application will most likely be approved if it meets the following criteria:

  1. Exposed height of the retaining wall does not exceed 36”.
  2. Materials compliment the character of the house.
  3. Long expanses of walls are broken up with insets or change of materials.
  4. Retaining walls do not block or affect an existing swale or drainage path in a manner to cause damming and small shallow pools/ puddles.
  5. Site plans show water run-off (use arrows to indicate flow of water).
  6. The location of the retaining wall cannot obstruct any swales or natural water run-off.
  7. No part of a retaining wall 36’’ or higher extends across the building restriction line (BRL), (typically 7.5 or more feet from the property line).

NOTE: Homeowner will be responsible for all safety concerns including any need for a railing on the retaining wall. Homeowner will coordinate with Howard County for all necessary building permits requirements.