Collin County's SSURGO septic rating

Very limited

Collin County, TX: USDA's soil survey calls 93.9% of the county "Very limited" for a septic leach field. Practically, that rules out a simple gravity system for most of the county - 93.9% of it sits in USDA's most-constrained bucket. The county spans 841.513 square miles, home to 1,254,658 people.

What this number does and doesn't tell you

This is a countywide, area-weighted figure across every soil survey map unit in Collin County, TX - never a reading for one specific parcel. Budget $750-$1,850 for a real perc test on any specific parcel - that's the only figure a permit application accepts.

Collin County: conventional vs. engineered cost

93.9% of Collin County carrying a "Very limited" reading changes the realistic budget here. 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.

How Collin County, TX compares

Among the 3,058 rated counties on this site, Collin County, TX ranks 793 most-constrained nationally, and 54 of 253 within Texas.

Before you act on this

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