Septic companies in Lewiston, ID

What the ground in Lewiston is like

The USDA soil survey rates mapped ground in Lewiston for septic drain-field suitability across roughly 18 square miles. About 51% of the rated ground is classed "Somewhat limited", the survey records restrictions that design and sizing can often work around.

In Lewiston, the leading limit is slow water movement: effluent does not drain through the soil fast enough, so a conventional field can back up or pond when the ground cannot keep pace. The survey flags that limit on about 95% of the rated ground here.

The limiting features the survey records most often here:

• Slow water movement95.0%
• Seepage, bottom layer39.1%
• Slope38.8%
• Depth to cemented pan5.2%

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 · 50.8% Somewhat limited · Slow water movement · 30 map units · 17.59 sq mi · read 2026-08-30