Septic suitability in Tuolumne County, CA

Very limited

Tuolumne County, CA's SSURGO dominant class comes back "Very limited", covering 91.8% of the county. A standard gravity system routinely fails on ground like this; the same share of the county falls in USDA's worst absorption-field bucket outright. For scale: 2,220.912 square miles and 53,893 people call Tuolumne County home.

Before you rely on this for one lot

USDA's survey covers the whole of Tuolumne County, CA at once, not any single address. The real answer for one lot is still a site-specific perc test, running about $750-$1,850 (typically near $1,300).

Budgeting for a system in Tuolumne County, CA

Tuolumne County's soil reading pushes the likely outcome toward an engineered system rather than a conventional one. Conventional systems run $3,000-$8,000 where they pass; where they don't, engineered alternatives (mound or aerobic treatment, whichever the health department requires) run $10,000-$40,000 - budget toward the higher figure until a perc test says otherwise.

Where this sits nationally

Among the 3,058 rated counties on this site, Tuolumne County, CA ranks 1,064 most-constrained nationally, and 27 of 57 within California.

Further reading

How this rating is built, and its real limits · Conventional vs. engineered septic systems