Meridian Retaining Walls covers new retaining walls and the replacement of old ones in Caldwell, Idaho. The city’s September 2026 building report lists a residential permit for a retaining wall replacement, and its permit packet says residential plan review takes not more than 5 to 7 working days with a complete submittal.
Some jobs start with a wall that’s giving up: timbers gone soft, block leaning out. Others start with a bare lot that needs grading, in a city that gained 5,160 residents between 2025 and 2026. Lots beside an irrigation district canal are covered too. Call us with the wall’s length and height, its distance from the house, and photos of the old wall if there is one.
- Residential plan review
- Not more than 5 to 7 working days, with a complete submittal
- Frost depth
- 24 inches
- Hardpan in Purdam soil
- 20 to 40 inches
- Permit fee plus building plan review, $5,000 wall
- $137.79
Retaining wall services in Caldwell: new walls and wall replacement
Retaining wall replacement in Caldwell
When a timber wall is rotting or a block wall has failed, the old wall comes out and a new one goes in. Start at retaining wall repair if it might be saved, or railroad tie wall replacement for tie walls.
New retaining wall on a graded lot
On a new subdivision lot, the wall can’t spoil the way the ground falls away from the house. The city wants ground to fall 6 inches in the first 10 feet from a foundation. See retaining wall installation.
Retaining wall near a Pioneer Irrigation District canal
On a canal-side lot, the district has its own application, and Pioneer charges a $4,250 encroachment application fee. Read retaining walls near canals before anyone draws a plan.
Replacing an old wall in Caldwell?
Call with the length and height and what sits above the wall.
What does a retaining wall permit cost in Caldwell?
It depends on the value of the job. Under the FY2026 fee schedule the fee is $64.37 at $2,000 of project value, plus $0.01135 for each dollar above that. Building plan review adds 40 percent.
| Step on a $5,000 wall | Sum | Result |
|---|---|---|
| Permit fee | $64.37 at $2,000, plus 3,000 x $0.01135 | $98.42. |
| Building plan review | 40 percent of $98.42 | $39.37. |
| Both together | $98.42 + $39.37 | $137.79. |
Source: City of Caldwell building permit fee schedule, FY2026.
Watch what goes into project value. The city counts grading, site preparation and landscaping, not just the wall. And the table’s total covers the permit fee and building plan review only. It may not be the whole bill, so confirm the full figure with the Building Safety Division.
For the permit line, start with Idaho’s and confirm it with the city. Under the residential code the state adopted, no building permit is needed for a wall not over 4 feet measured from the bottom of the footing to the top, unless it supports a surcharge. The retaining wall permits page shows how that 4 feet is measured.
On a replacement, tearing out the old wall comes first, and removal typically runs $10 to $20 per square foot, plus $20 to $30 for hauling and disposal, going by typical US figures from January 2025. Prices change, and these aren’t a quote for your wall. The old wall’s length and height, and how a machine reaches it, all move the number. Ranges for the new wall are on the retaining wall cost page. Send us the measurements, and we’ll help you find a Caldwell contractor to put a number on it.
Call (208) 445-1999 to talk it throughor request a quote online
How long does Caldwell plan review take, and how do you apply?
Not more than 5 to 7 working days for residential plan review, according to the city’s permit packet, and only with a complete submittal. Other offices’ published times are on the Treasure Valley areas page.
You can apply through the city’s online permit portal, and any resubmittal has to go back through it too. The office is the Building Safety Division at 205 South 6th Ave. Once the wall is under way, a same-day inspection request has to reach the division by 7:00 a.m.
Hardpan, frost depth and winter groundwater under a Caldwell wall
Purdam soil, described near Caldwell and extensive in southwest Idaho, has a cemented hardpan 20 to 40 inches down, under a subsoil of 24 to 32 percent clay. The city’s design criteria set a 24 inch frost depth. Put the two side by side and frost depth lands inside the hardpan band, 4 inches past its shallowest figure. So a trench dug to frost depth can hit cemented ground.
The clay matters for drainage. Block manufacturer guidance calls for a drain pipe behind any wall built in silty or clay soil, short walls included. See retaining wall drainage.
The city’s stormwater manual (March 2024) presumes groundwater readings taken between November 1 and March 30 are seasonally low, and requires 2 feet to be added to the highest measured level. That’s a stormwater design rule, not a wall rule.
The soil survey maps ground across a wide area, so it can’t say what’s under your lot. A test hole can.
Want to know what the city will review?
Permits, engineering, drainage or price: ask before you commit.
Grading away from the house when a retaining wall is in the way
Caldwell’s fine grading rule asks for 6 inches of fall in the first 10 feet from a foundation. Where walls or lot lines prevent that, the ground has to slope away at 5 percent instead.
A wall set near the house can be the thing that prevents it. Tell us the distance from the house to the wall line when you call.
Irrigation season and canal-side lots in Caldwell
The city’s irrigation district runs pressurized irrigation from mid to late April until early October. A yard that looks dry in February says little about July.
A canal-side lot can mean a second approval, separate from the city’s. Pioneer charges a $4,250 encroachment application fee, so ask the district before anything is built in or near its easement. Ask, too, which months it allows work beside its canals.
If a canal runs along the back line, say so in the first call.
What to look for in a Caldwell retaining wall quote
- Removal of the old wall as its own line Tear-out and hauling priced apart from the new wall.
- The project value that goes on the permit The city counts grading, site preparation and landscaping in it.
- Footing depth against frost and hardpan Ask what happens if cemented ground turns up above frost depth.
- A drain pipe, named, with its outlet Clay subsoil is why it’s on this list.
- The fall back to the foundation Six inches in 10 feet, or 5 percent.
- The district’s application, where a canal is near Who files it, and which line of the quote carries the $4,250.
Caldwell retaining wall questions
Can a retaining wall be repaired, or does it have to be replaced?
It depends on what’s wrong. If segmental block has settled in one spot, one block maker’s guidance is to unstack that section, raise the base and restack the blocks. A leaning wall is different. Another block maker says it can’t be pushed back, and describes the fix as taking the wall down, correcting base, drainage and setback, then restacking.
Does replacing a retaining wall need a permit in Caldwell?
It can. The city’s September 2026 building report lists a residential permit for a wall replacement, so ask the Building Safety Division about yours.
How much is a retaining wall permit in Caldwell?
$137.79 at $5,000 of project value, under the FY2026 schedule. That’s the permit fee plus building plan review, and nothing else the city may bill.
Don't see your question? Call (208) 445-1999.
Sources and review date
Reviewed October 2026. Sources: City of Caldwell Building Safety pages, permit packet, fee schedule, grading and stormwater rules, irrigation page and building report; Idaho residential code; Pioneer Irrigation District; federal soil survey; regional planning agency; national cost guides; block manufacturers' guidance.