Published and sources reviewed: October 26, 2026. Rain can make water routes and surface changes easier to see, but weather alone does not prove that a retaining wall or slope is damaged. Use this guide to make careful observations from stable ground and to prepare better questions for a site-specific assessment.
1. Start from a safe viewing point
Stay off soft banks, saturated fill and the area directly below a wall that is leaning, bulging or shedding material. Do not enter moving water, climb onto a wet wall, pull blocks back into place, or dig at the toe to look for a drain. If movement is active, a supported driveway or structure is affected, or soil is giving way, keep people away and seek prompt qualified help.
A photograph from the side can show alignment better than a close-up. Take it from the same stable location each time. A visible change is useful evidence; a photograph cannot certify stability.
2. Record changes without guessing the cause
Look for new gaps, rotation, bulging, settlement behind the wall, fresh soil cracking, erosion channels, exposed fabric, displaced caps, or material collecting at the bottom. Note the date, approximate location and whether the condition was present before the rain.
These signs can have different causes. Do not label a wall failed or safe from one symptom. Wall geometry, retained height, soil, drainage, nearby loads, workmanship and the history of movement all matter.
3. Follow the visible water route
From safe ground, identify where roof runoff, paving and uphill grades deliver water. Note ponding behind the wall, water emerging through joints, erosion near the ends, and whether the apparent outlet is flowing. A dry wall face does not establish that drainage behind it is working, and water through a face does not by itself identify the hidden detail.
The City of Nanaimo's stormwater guidance, updated September 15, 2026, says to keep yard waste and gravel out of ditches, clear accessible catch-basin debris only when safe, and not clear culverts yourself. Call Public Works at 250-758-5222 for culvert help. Keep soil, concrete residue and other construction waste out of drains and ditches.
4. Check planning and permit questions before rebuilding
The City's retaining-wall permit page, updated June 20, 2024, says a building permit is generally required over 4 feet, while other factors can also affect whether a permit is needed. It also directs owners to consider property lines, rights-of-way, easements and the current Retaining Wall Guide. Do not assume a wall below 4 feet is automatically exempt or suitable to rebuild in the same form.
For RDN properties, the RDN Sustainable Site Planning Guide is a starting point for understanding local context, soil, slopes, existing infrastructure and drainage before design. Municipal, RDN and other jurisdictional requirements differ; confirm the rules for the actual address.
5. Prepare a useful assessment brief
Bring wide photographs, close-ups of changes, approximate wall length and exposed height, the date changes were first noticed, and a sketch showing the house, driveway, property boundary, slope direction, downspouts and visible outlets. Include any previous drawings, permits, engineering information or repair records.
Explain what the wall supports and identify loads above it such as a driveway, building, steep bank or another wall. Access, disposal, utilities and the finished surface to be restored also affect an excavation or rebuilding plan.
A drainage contractor can review water-routing questions and visible drainage features. A retaining wall that supports significant loads, shows movement or falls within permit or professional-design requirements may also need the appropriate engineer, geoscientist or building authority.
Bring the record to a paid diagnostic visit
Fairytale's residential diagnostic audit is $450, including 1.5 on-site hours; extra time is $150/hour. The pre-purchase inspection is $650. Flush-and-inspect is $950–$1,250, with specialized support when needed. Suitability, scope and charges are confirmed before booking.
Start with an inspection plan
Tell Clayton what you have noticed and send property photos. Camera inspections and technical investigations are paid services; suitability, scope and charges are confirmed before booking.
Request a camera inspection