Soil and perc tests in Guilford County, North Carolina

USDA rates most of the soil in Guilford County Very limited for septic absorption fields — 67.5% of the rated acres. The county evaluates the soil and the site to decide whether a lot can support a septic system. North Carolina does not use a percolation test. USDA NRCS Soil Data Access (SSURGO) · checked 2026-09-16

Very limited

USDA rating, 67.5% of rated acres

checked 2026-09-16

Slow water movement

Most common limiting reason

checked 2026-09-16

Yes

Site evaluation required

checked 2026-09-23

What is a perc test and does Guilford County require one?

Yes. The county evaluates the soil and the site to decide whether a lot can support a septic system. North Carolina does not use a percolation test.

The county reviews the system design when a design is needed, after the soil evaluation.

Guilford County — On-site Wastewater · checked 2026-09-23

How USDA rates the ground in Guilford County

Very limited across most of the county — 67.5% of the rated acres. A rating describes the ground, not a parcel. The county's site evaluation decides each lot.

Very limited — 241,304 acres — 67.5% of 357,726 rated acres.
Somewhat limited — 116,422 acres — 32.5% of 357,726 rated acres.
Not rated — 24,981 acres, excluded from the denominator — mostly urban land and water.

67.5% of 357,726 rated acres. 24,981 acres unrated. Survey area NC081 version 24, established 2025-09-02.

USDA NRCS Soil Data Access (SSURGO) · checked 2026-09-16

What limits absorption here

The reasons USDA gives for the rating, by the acres they affect. A component can carry several, so the acres overlap.

Slow water movement — 345,052 acres. Reasons overlap — a component can carry several — so these acres exceed rated acres.
Seepage, bottom layer — 74,283 acres. Reasons overlap — a component can carry several — so these acres exceed rated acres.
Slope — 52,574 acres. Reasons overlap — a component can carry several — so these acres exceed rated acres.
Depth to saturated zone — 36,213 acres. Reasons overlap — a component can carry several — so these acres exceed rated acres.
Flooding — 24,654 acres. Reasons overlap — a component can carry several — so these acres exceed rated acres.
Depth to bedrock — 22,992 acres. Reasons overlap — a component can carry several — so these acres exceed rated acres.
Filtering capacity — 96 acres. Reasons overlap — a component can carry several — so these acres exceed rated acres.

Ratings by soil map unit

The largest map units in the county, each with its rating. A soil survey names the ground. The county's evaluation of your lot is what a permit turns on.

EnB — Enon fine sandy loam, 2 to 6 percent slopes — 45,312 acres in this county — rated Very limited. Dominant component: Enon (90% of the map unit).
EnC — Enon fine sandy loam, 6 to 10 percent slopes — 31,923 acres in this county — rated Very limited. Dominant component: Enon (85% of the map unit).
MhB2 — Mecklenburg sandy clay loam, 2 to 6 percent slopes, moderately eroded — 21,869 acres in this county — rated Very limited. Dominant component: Mecklenburg (90% of the map unit).
CkB — Clifford sandy loam, 2 to 6 percent slopes — 19,268 acres in this county — rated Somewhat limited. Dominant component: Clifford (90% of the map unit).
EuB — Enon-Urban land complex, 2 to 10 percent slopes — 16,885 acres in this county — rated Very limited. Dominant component: Enon (50% of the map unit).
CeB2 — Cecil sandy clay loam, 2 to 6 percent slopes, moderately eroded — 13,845 acres in this county — rated Somewhat limited. Dominant component: Cecil (90% of the map unit).
EnD — Enon fine sandy loam, 10 to 15 percent slopes — 13,265 acres in this county — rated Very limited. Dominant component: Enon (75% of the map unit).
ApB — Appling sandy loam, 2 to 6 percent slopes — 12,833 acres in this county — rated Somewhat limited. Dominant component: Appling (92% of the map unit).

USDA NRCS Soil Data Access (SSURGO) · checked 2026-09-16

Sources

Each figure on this page has a government source and a checked-on date.

Guilford County — On-site Wastewater · checked 2026-09-23
Guilford County — Water Quality · checked 2026-09-23
Guilford County Environmental Health Fee Schedule · checked 2026-09-23
15A NCAC 18E .0801, Septic Tank Capacity Requirements · checked 2026-09-23
USDA NRCS Soil Data Access (SSURGO) · checked 2026-09-16

Verify before you act. Septic rules are set locally and they change. Check anything here before you spend money on it. Call the county environmental health office, on 336-641-7613.