HomeLouisianaSt. Helena Parish

St. Helena Parish, Louisiana

A shallow water table limits basements on 66% of St. Helena Parish's mapped land, a higher share than 79% of US counties. Shrink-swell clay limits houses without basements on 0%.

100% of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 37 flood losses here since 2016, 0% of them in buildings with basements. 35% of homes were built before 1980, against 50% nationally; the median home dates from 1987.

Data as of October 13, 2026 · sources

0%

expansive clay: shrink-swell limits slab homes

66%

high water table: limits basements

100%

in drought, October 13, 2026

35%

of homes built before 1980

Soil under St. Helena Parish

Expansive clay (limits slab homes)0.0%
High water table (limits basements)66.5%
Septic fields very limited81.6%
Clay swell (LEP, by area)1.5%
High-swell land (LEP 6%+)0.0%
Mapped soil262,000 acres
Soil seriesShare hereSeries nationally: high water table
Tangi26%n/a
Ruston13%n/a
Ouachita10%n/a
Ochlockonee9%n/a
Toula8%n/a
Smithdale6%0%
East Feliciana Parish: 67%Tangipahoa Parish: 73%Livingston Parish: 86%Amite County: 67%East Baton Rouge Parish: 72%Pike County: 71%Washington Parish: 51%West Feliciana Parish: 45%St. Helena Parish East FelicianaTangipahoaLivingstonAmiteEast Baton RougePikeWashingtonWest FelicianaSt. Helena
St. Helena Parish (heavy outline) and nearby counties, shaded by high water table share.under 10%10-25%25-40%40-60%60%+

How we count · survey areas LA091 (2025-08-29)

What the numbers mean here

On 66% of St. Helena Parish's mapped land, soil stays saturated within about 6 feet of the surface for part of the year, which is basement depth.

Rain over the 12 months to August 2026: 57.96 in, 5.91 in below the 1991-2020 average year of 63.87 in.

USDA rates 82% of the land very limited for septic absorption fields.

Drought

100% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 13 of the last 52 weeks; the most was 100% of its area, in 8 weeks, most recently on the October 13, 2026 map.

October 21, 2025Share of area in drought, weeklyOctober 13, 2026
Category, October 13, 2026Share of county
D0 abnormally dry or worse100%
D1 moderate drought or worse100%
D2 severe or worse84.3%
D3 extreme or worse0%
D4 exceptional0%

Flood losses since 2016

37 flood losses since 2016, $2.3 million paid. The worst year was 2016, with 31. Foundations of the buildings, where recorded: 45% slabs, 14% crawl spaces, 41% elevated.

YearFlood losses
201631
20170
20180
20190
20200
20215
20220
20230
20240
20250
2026 to date1

Rain

Average year, 1991-202063.87 in
12 months to August 202657.96 in (-5.91)
202552.30 in (-11.57)
Wettest year since 18951905: 90.43 in
Driest year since 18951924: 40.94 in
Days with 1 inch or more, normal at PINE GROVE FIRE TWR (8 mi away)21.9

Homes

Housing units5,355
Median year built1987
Built before 198035%
Built 2000 or later31%
Owner-occupied79%
Median value, owner-occupied$77,300
Single-family detached50%

What repairs cost

Published ranges from cost guides, not quotes. More sources, and where they disagree.

WorkRangeSource
Basement waterproofing, US $3,000 to $10,000 Fixr, February 6, 2026
Sump pump installation, US $800 to $2,000 Fixr, January 31, 2025
Crawl space encapsulation, US $2,000 to $8,000 Fixr, August 29, 2025

Nearby counties

PlaceDistanceExpansive clayHigh water table
East Feliciana Parish, LA 20 mi under 1% 67%
Tangipahoa Parish, LA 23 mi 2% 73%
Livingston Parish, LA 26 mi 27% 86%
Amite County, MS 27 mi 2% 67%
East Baton Rouge Parish, LA 30 mi 7% 72%
Pike County, MS 31 mi 0% 71%
Washington Parish, LA 39 mi under 1% 51%
West Feliciana Parish, LA 42 mi 14% 45%

Sources: USDA SSURGO (August 29, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status