Septic companies in Astoria, OR

What the ground in Astoria is like

The USDA soil survey rates mapped ground in Astoria for septic drain-field suitability across roughly 6.1 square miles. About 95% of the rated ground is classed "Very limited", the survey records severe restrictions for a conventional drain field across most of that ground.

In Astoria, the leading limit is slope: the ground falls steeply enough that a level trench line is hard to hold. A drain field has to sit across the grade without concentrating flow downhill; on steeper parcels that layout gets tighter. The survey flags that limit on about 79% of the rated ground here.

The limiting features the survey records most often here:

• Slope78.9%
• Slow water movement74.9%
• Depth to bedrock59.4%
• Seepage, bottom layer25.1%

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 · 95.4% Very limited · Slope · 16 map units · 6.11 sq mi · read 2026-08-30