Clackamas County, OR Fence Regulations: Retaining Walls (2026)
Key Facts
- Zoning status
- Permitted use (all R districts)
- Building permit trigger
- Generally over 4 feet tall
- Surcharged walls
- Permit regardless of height
- Corner vision
- 30 in. within 20 ft
- Permit desk
- Clackamas County Building
Summary
Retaining walls are a permitted accessory use in unincorporated Clackamas County residential districts, but taller walls require a building permit and engineering under the Oregon structural/residential code, and all walls must respect corner-vision and setback standards.
Fences and Retaining Walls [listed as] P [permitted primary/accessory use in the urban residential zoning districts].
Full Breakdown
The ZDO lists 'Fences and Retaining Walls' as a permitted use in the urban residential districts. Under Oregon's adopted building code, a retaining wall over 4 feet in height (measured bottom of footing to top), or any wall supporting a surcharge, requires a building permit and engineered design; shorter, unloaded walls typically do not. Walls must also comply with the ZDO's 30-inch corner-vision limit within 20 feet of intersections and cannot be placed to obstruct sight lines. Apply through Clackamas County Building Codes.
Violations & Fines
Building an over-height or surcharged retaining wall without the required building permit is a violation subject to stop-work orders, permit-after-the-fact penalties, and correction requirements.
Frequently Asked Questions
Do I need a permit for a retaining wall?
Are retaining walls even allowed?
Sources & Official References
Other rules in Clackamas County
Compare Clackamas County to another location·View the Oregon fence regulations overview
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