Very limited
USDA rating, 77.8% of rated acres
checked 2026-10-06
Slow water movement
Most common limiting reason
checked 2026-10-06
Yes
Site evaluation required
checked 2026-09-23
What is a perc test and does Wise County require one?
Yes. Texas requires a site evaluation before it issues a permit.
A site evaluator or an engineer checks the soil in two pits or borings. The evaluator also checks for shallow groundwater and reviews slope and flood risk. The county uses this report to set the system's size.
Texas Administrative Code, Title 30, Chapter 285, Section 285.30, Site Evaluation · checked 2026-09-23
How USDA rates the ground in Wise County
Very limited across most of the county
— 77.8% of the rated acres.
A rating describes the ground, not a parcel. The county's site evaluation decides each lot.
- Very limited — 394,935 acres — 77.8% of 507,896 rated acres.
- Somewhat limited — 112,961 acres — 22.2% of 507,896 rated acres.
- Not rated — 83,068 acres, excluded from the denominator — mostly urban land and water.
77.8% of 507,896 rated acres. 83,068 acres unrated. Survey area TX497 version 24, established 2026-09-03.
USDA NRCS Soil Data Access (SSURGO) · checked 2026-10-06
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 — 417,377 acres. Reasons overlap — a component can carry several — so these acres exceed rated acres.
- Depth to bedrock — 225,440 acres. Reasons overlap — a component can carry several — so these acres exceed rated acres.
- Flooding — 69,504 acres. Reasons overlap — a component can carry several — so these acres exceed rated acres.
- Seepage, bottom layer — 64,095 acres. Reasons overlap — a component can carry several — so these acres exceed rated acres.
- Slope — 51,407 acres. Reasons overlap — a component can carry several — so these acres exceed rated acres.
- Depth to saturated zone — 30,991 acres. Reasons overlap — a component can carry several — so these acres exceed rated acres.
- Large stones — 3,889 acres. Reasons overlap — a component can carry several — so these acres exceed rated acres.
- Ponding — 7 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.
- SoC — Somervell-Aledo complex, 1 to 8 percent slopes — 35,985 acres in this county — rated Very limited. Dominant component: Somervell (50% of the map unit).
- WeD — Duffau-Weatherford complex, 3 to 8 percent slopes — 27,849 acres in this county — rated Somewhat limited. Dominant component: Duffau (48% of the map unit).
- KtC — Keeter very fine sandy loam, 1 to 6 percent slopes — 27,421 acres in this county — rated Very limited. Dominant component: Keeter (80% of the map unit).
- ChB — Chaney loamy sand, 1 to 5 percent slopes — 25,421 acres in this county — rated Very limited. Dominant component: Chaney (85% of the map unit).
- WtC — Windthorst fine sandy loam, 1 to 5 percent slopes — 21,779 acres in this county — rated Very limited. Dominant component: Windthorst (85% of the map unit).
- KtC3 — Keeter very fine sandy loam, 2 to 6 percent slopes, severely eroded — 21,646 acres in this county — rated Very limited. Dominant component: Keeter (80% of the map unit).
- VeC — Venus loam, 3 to 8 percent slopes — 21,563 acres in this county — rated Somewhat limited. Dominant component: Venus (92% of the map unit).
- WeC3 — Weatherford-Duffau complex, 2 to 8 percent slopes, severely eroded — 20,475 acres in this county — rated Somewhat limited. Dominant component: Weatherford (45% of the map unit).
USDA NRCS Soil Data Access (SSURGO) · checked 2026-10-06
Verify before you act. Septic rules are set locally and they change. Check anything
here before you spend money on it. Call the Wise County Environmental Services, on 940-627-9332.