Septic soil in Calcasieu Parish, LA, by the numbers

Very limited

91.6% of Calcasieu Parish, LA's surveyed soil comes back "Very limited" in USDA's own SSURGO data, the county's dominant condition for a septic absorption field. This is the reading that pushes a project toward an engineered system rather than a conventional one, and it covers 91.6% of Calcasieu Parish's land. Calcasieu Parish, LA is 1,064.189 square miles with a population of 206,861.

What Calcasieu Parish's reading doesn't cover

USDA's survey covers the whole of Calcasieu Parish, LA at once, not any single address. A local percolation test, typically $750-$1,850 (around $1,300 typical), is the only way to know what one lot in Calcasieu Parish will actually do.

What a system would cost here

With 91.6% of Calcasieu Parish rating "Very limited", a standard gravity system is not a safe assumption here. The engineered-system range, $10,000-$40,000 (mound or aerobic treatment), is the more realistic number to plan around, against $3,000-$8,000 for a conventional system on the rare lot that passes.

Calcasieu Parish's rank among Louisiana counties

Nationally, Calcasieu Parish, LA is the 1,092-most-constrained of 3,058 rated counties for septic soil. Within Louisiana alone it ranks 13 of 61.

Further reading

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