Caldwell, Idaho: what the ground under the city is like
Caldwell sits in Canyon County, on snake river plain. The soil mapped here is predominantly classified well drained — and that classification, not the rainfall total, is what decides how a basement behaves.
16% of the mapped soil area around Caldwell is wet enough that the USDA describes it as needing artificial drainage.
Linear extensibility 4.6% — moderate.
Shallowest annual water table around 155 cm (5.1 ft).
Values are for Canyon County, which is what the soil survey resolves to. Full county report · soil map for a specific address.
The ground under Caldwell
Snake River Plain. Aeolian loess over basalt, shallow bedrock
Basalt sits just below a loess cap. Excavating for a basement is expensive, and where one exists it often bears directly on rock — which does not move, but does not let water through either.
When it shows up here
| Water | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ground movement | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
Rainfall is low all year, so the water line stays flat. What moves is the ground: the late spring and early summer dry-down is the sharpest part of the cycle, and summer monsoon storms end it abruptly.
Climate pattern for this physiographic region, not a forecast for your house and not from the soil survey. It answers a question homeowners actually ask: when does this show up.
What repairs cost in Idaho
| Reference job | Modelled range |
|---|---|
| Interior drain along two walls + sump pump | $5,050–$10,850 |
| Exterior excavation of one 40 ft wall | $3,800–$10,800 |
| Underpinning on 10 piers | $15,000–$32,000 |
Regional factor for ID: ×1.00. Full cost breakdown for Idaho · run your own dimensions.
ZIP codes in Caldwell
83605, 83606, 83607
Soil does not stop at a city boundary, and neither does this data — every ZIP code above resolves to the same county soil survey. For the individual survey polygons around one address, use the soil map.
Other places in Canyon County
Questions about Caldwell
Is the soil the same everywhere in Caldwell?
No. These values describe Canyon County as a whole, which is the unit the soil survey publishes. Within a city, map units change over a few hundred metres — the soil map draws the actual polygons around a point and is the honest answer for one address.
Which contractor should I call in Caldwell?
We do not rank or recommend individual firms and we are not one. What this page is for is knowing which kind of work the ground here points to before anyone quotes you, and which claim to check. If you want quotes, the form below passes your request to the named networks.
Does this replace an inspection?
No. It tells you what the ground is; an inspection tells you what your building is doing on it. The useful order is: read this, print the brief for your county, then have someone look.
Get quotes in Caldwell
We pass what you enter to the contractor networks listed below. You choose whether to hire anyone.
Page data updated