Septic companies in Post Falls, ID

What the ground in Post Falls is like

The USDA soil survey rates mapped ground in Post Falls for septic drain-field suitability across roughly 19 square miles. About 100% of the rated ground is classed "Very limited", the survey records severe restrictions for a conventional drain field across most of that ground.

In Post Falls, the leading limit is seepage in the bottom layer: water moves through the soil too quickly. That is the opposite of a slow-drainage problem. The risk is untreated effluent reaching groundwater before the soil can clean it, not backup at the surface. The survey flags that limit on about 100% of the rated ground here.

The limiting features the survey records most often here:

• Seepage, bottom layer99.9%
• Slow water movement59.0%
• Slope7.9%
• Depth to bedrock4.2%

This is survey data for mapped areas, not a substitute for a site evaluation on your own lot. Conditions on a single parcel can differ from the map.

USDA NRCS SSURGO, ENG Septic Tank Absorption Fields · 100% Very limited · Seepage, bottom layer · 19 map units · 19.16 sq mi · read 2026-08-30