Soil series profile

Niagara soil series

Niagara is a somewhat poorly drained soil with a silt loam surface, mapped on 148,056 acres in 25 counties across 2 states. Hydrologic group C/D.

#2491 by mapped area fine-silty Aeric Ochraqualfs (Alfisols)

Drainage class
Somewhat poorly drained
99% of mapped acres
Hydrologic group
C/D
94% of mapped acres
Typical topsoil pH
6.2
slightly acidic · range 6.2–6.2
Mapped area
148k
acres in 25 counties, 2 states

Typical Niagara profile

Texture and pH by depth

Typical Niagara soil profile by depth 0 in 10 in 20 in 30 in 40 in 50 in 0–11 in · H1 · pH 6.2 · 22% clay Silt loam 11–39 in · H2 · pH 6.7 · 22% clay Silt loam 39–60 in · H3 · pH 7.5 · 12% clay Stratified silt loam to loamy very fine sand
Depth to scale. More strongly shaded layers hold more clay. Horizon names are the soil survey's (A = topsoil, B = subsoil, C = parent material).
Show as a table
Typical Niagara horizons (representative values)
Depth Texture pH Clay Sand Organic matter
0–11 in (H1) Silt loam 6.2 22% 11% 4%
11–39 in (H2) Silt loam 6.7 22% 11% 1%
39–60 in (H3) Stratified silt loam to loamy very fine sand 7.5 12% 53% 0.5%

Representative values from the most extensive Niagara map unit (Niagara silt loam, 0 to 4 percent slopes, survey area NY067). Other map units of this series vary within the series range.

Hands holding dark garden soil
Stock photo for illustration, not a sample of this soil series. Credit on the Sources & method page.

What this means

What Niagara soil means for gardens, lawns and septic systems

For gardens

Typical topsoil in Niagara soils is slightly acidic: pH 6.2, the range most vegetables, flowers and lawn grasses prefer.

Loamy topsoil (loam, silt loam and similar) covers 96% of mapped Niagara acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is silt loam (93% of mapped Niagara acres).

99% of mapped Niagara acres is somewhat poorly to very poorly drained, so soil stays soggy for long spells after rain and in wet seasons. Raised beds, plants that tolerate wet feet, and not working the soil while wet all help.

For lawns and yards

On 96% of mapped acres, rain soaks in slowly (hydrologic groups C and D, including dual groups that are D until drained). Expect runoff and puddles after heavy rain: core-aerate compacted lawns and keep ground sloping away from foundations.

A seasonal high water table comes within 18 inches of the surface on 96% of mapped acres, often in spring. Basements, sump pumps and lawns in low spots feel it first.

For a septic system

For conventional septic absorption fields, NRCS rates 96% of the acres in mapped Niagara soils very limited, 0% somewhat limited and 0% not limited (4% not rated, such as urban land, pits or water).

Where the soil is very limited (slow permeability, a high water table, flooding, shallow bedrock or steep slopes), alternative systems such as mound or sand-filter designs are common and cost more.

Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.

Generated from the mapped numbers above using fixed rules, not a site visit. See how these notes are written.

Where Niagara soil is found

Mapped acres

Niagara is mapped in New York and Pennsylvania.

Counties with the most mapped Niagara soil
County Acres Share of county land
Erie County, NY 22,677 3.5%
Onondaga County, NY 18,762 3.8%
Chautauqua County, NY 17,225 2.6%
Jefferson County, NY 16,932 2.1%
Monroe County, NY 12,049 2.9%
Orleans County, NY 7,741 3.1%
Niagara County, NY 7,505 2.3%
Cayuga County, NY 5,592 1.3%
Cattaraugus County, NY 5,247 0.7%
Genesee County, NY 4,647 1.5%
Madison County, NY 4,593 1.1%
Oneida County, NY 4,288 0.6%
Allegany County, NY 4,129 0.6%
Livingston County, NY 3,837 0.9%
Columbia County, NY 3,167 0.8%
Erie County, PA 1,814 0.4%
Wayne County, NY 1,438 0.4%
Seneca County, NY 1,363 0.7%
Essex County, NY 1,188 0.1%
Ontario County, NY 755 0.2%
Steuben County, NY 705 0.1%
Tompkins County, NY 519 0.2%
Yates County, NY 419 0.2%
Wyoming County, NY 354 0.1%
Cortland County, NY 233 0.1%

Septic absorption fields

NRCS rating, share of Niagara acres

Not limited 0%
Somewhat limited 0%
Very limited 96%
Not rated 4%
Septic tank absorption field rating across mapped Niagara acres. Scale 0 to 100% of mapped land.
Show as a table
Septic tank absorption field rating across mapped Niagara acres.
CategoryShare of acres
Not limited0.0%
Somewhat limited0.0%
Very limited95.8%
Not rated4.2%

Drainage, water table and flooding

Share of Niagara acres

Depth to seasonal high water table
About 1.0 feet (12 in) (median where reported); within 18 inches on 96% of acres.
Flooding
Not mapped as flooding on most acres.
Slope
Typically 1–4% (median 2%).
Topsoil organic matter
Median 4%.

Drainage class

Excessively drained 0%
Somewhat excessively drained 0%
Well drained 0%
Moderately well drained 0%
Somewhat poorly drained 99%
Poorly drained 0%
Very poorly drained 0%
Not rated 1%
Drainage class across mapped Niagara acres. Scale 0 to 100% of mapped land.
Show as a table
Drainage class across mapped Niagara acres.
CategoryShare of acres
Excessively drained0.0%
Somewhat excessively drained0.0%
Well drained0.0%
Moderately well drained0.0%
Somewhat poorly drained98.9%
Poorly drained0.0%
Very poorly drained0.0%
Not rated1.1%

Hydrologic soil group

A: fast infiltration (mostly sandy or gravelly) 0%
B: moderate infiltration 0%
C: slow infiltration 0%
D: very slow infiltration (clayey, shallow or wet) 0%
A/D: D as is, A if drained 0%
B/D: D as is, B if drained 2%
C/D: D as is, C if drained 94%
Not rated 4%
Hydrologic soil group across mapped Niagara acres. Scale 0 to 100% of mapped land.
Show as a table
Hydrologic soil group across mapped Niagara acres.
CategoryShare of acres
A: fast infiltration (mostly sandy or gravelly)0.0%
B: moderate infiltration0.0%
C: slow infiltration0.0%
D: very slow infiltration (clayey, shallow or wet)0.0%
A/D: D as is, A if drained0.0%
B/D: D as is, B if drained2.2%
C/D: D as is, C if drained93.6%
Not rated4.2%

Sources & data dates

Source
USDA NRCS Soil Survey Geographic Database (SSURGO), queried through Soil Data Access. Public domain.
Data date
SSURGO as published on November 3, 2026 (most recent survey area update October 26, 2026). NRCS refreshes SSURGO each October.
Scope
All map unit components named Niagara (component kind "Series") in SSURGO: 148,056 acres.
Method
Shares are by mapped acres of Niagara components. The profile comes from the single largest Niagara component. Full methodology.

Independent reference site. No government affiliation or endorsement.

Full narrative description: USDA Official Soil Series Description for Niagara.