TL;DR
The seasonal high water table is the highest level groundwater reaches during the wettest part of a typical year, identified in a soil pit by gray mottling and iron stains rather than by the water present on inspection day. Septic regulations key on it because most states require 18 to 48 inches of unsaturated soil between the drainfield bottom and that level for effluent treatment.
What it means
The seasonal high water table is the highest level groundwater reaches during the wettest part of a typical year, identified in a soil pit by gray mottling and iron stains rather than by the water present on inspection day. Septic regulations key on it because most states require 18 to 48 inches of unsaturated soil between the drainfield bottom and that level for effluent treatment. A high reading is what forces a mound or other alternative system instead of a conventional one.
Where it sits in the glossary
Seasonal high water table is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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