Planning project · Planning application
Retaining wall in Boise foothills hillside area sought on third-acre lot
The city is reviewing a request to build a retaining wall on a 0.33-acre residential lot in the Hillside Overlay. Staff say it needs a geotechnical report and detailed civil plans because of slope and soil hazards. City staff will decide the application.
From the filing
The application's description as it appears in City of Boise's record. See the official record
Retaining wall in Hillside Overlay
Project name on file: 855 E CHARDIE RD
Timeline
April 23, 2026
Pending Application Submittal: Planning Applications in Review
April 21, 2026
Concept Review Complete: Engineering Preview Complete
A determination has been made that this project will be a Category II Hillside project due to slope, erosion-prone soils, unstable soils, earth movement, and other geologic and hydrologic hazards. In addition to the already submitted documents, additional documents may be required during the CFH Review process.Additional documents that you can expect to provide will be a site-specific geotechnical report with the a global slope stability analysis (please see the Agency Comment for Hillside Retaining Wall Permitting within this PLN); structural calculations for any retaining wall system that is greater than four feet in height from top of foundation to top of wall, that has more than one wall when the interior horizontal distance between the walls is less than 10 feet and the total height of all walls exceeds four feet, that has a surcharge, that has a backslope greater than three feet horizontal to one foot vertical, or that has structural components (these requirements will be assessed again at the time of occupancy); and detailed civil plans. Please refer to the Hillside Development Requirements for Technical Reports for grading & drainage plan and geotechnical report requirements.A subgrade inspection by a geotechnical firm will be required at the time of construction once the subgrade is exposed and prior to placement of foundation materials or forms/rebar. A report of the inspection will need to be submitted and accepted by PW Hillside (HillsideDrainage@cityofboise.org) before scheduling your inspection with the Building Department and receiving final occupancy.NOTE: The hazards of developing and building on a property, especially in the Boise foothills, are well known. It is the responsibility of the applicant/owner’s design, geological, and engineering professionals, not the City, to identify, address, and mitigate any hazards to the site. Satisfying these Conditions of Approval is for limited [City purpose] only and should not be relied on for design, geological or engineering purposes. Developer will comply with all requirements of Boise City Hillside Development Code Sections or submit evidence satisfactory to the Boise City Engineer that the proposed development is exempt from the requirements therein stated due to location, topography and/or the absence of adverse conditions associated with slope stability, ground water, erosion and sedimentation.If you would like to discuss this determination, please contact us at HillsideDrainage@cityofboise.org or we can set up a meeting if you prefer.
April 21, 2026
Concept Review Complete: CR Complete - Type 2
April 20, 2026
Concept Review Complete: Engineering Preview
April 7, 2026
Concept Review Complete: Corrections Required
Please submit a Site Plan.
April 6, 2026
Concept Review Complete: Corrections Required
Please submit a Site Plan. Our engineer will need additional information to determine if a Cat I or Cat II Hillside review is required for this project.
April 6, 2026
Concept Review Complete: Engineering Preview
March 30, 2026
Concept Review Complete: Hillside Questionnaire Needed
March 27, 2026
Application Submittal: Online
March 27, 2026
Application filed
Documents
Plans
- Download Retaining wall construction plans and general notes
ABCO Engineering sheet with keynotes and general notes for a rockery retaining wall, covering backfill, drainage geotextile, leveling pad, and footing subgrade testing.
April 15, 2026 · 4 pages · 1.7 MB · PDS-Other Small Docs
Project narrative
- Download Concept review summary
Advisory concept review notes classifying the project as a Category II Hillside application and listing expected geotechnical, retaining wall and civil documents.
April 21, 2026 · 2 pages · 464 KB · PDS-Concept Review Summary Report
Application
- Download Planning project application form
Application for installing boulder retaining walls on a residential R-1B lot, filed by a placing company on the owner's behalf, with a hillside questionnaire referenced.
March 27, 2026 · 2 pages · 157 KB · PDS-Application
Correspondence
- Download Hillside retaining wall permitting guidance
Public Works guidance on when retaining walls in the hillside zone need a determination, slope stability analysis, and planning-code height and setback limits.
April 21, 2026 · 5 pages · 804 KB · PDS-Agency Comments
Other documents
- Download Hillside project questionnaire
Public Works questionnaire answering whether the project involves new grading over 12 inches deep, with no lot line, dwelling, road, or addition changes and no retaining walls over 4 feet.
March 30, 2026 · 1 page · 689 KB · PDS-Other Small Docs
