Can you drill a well without a permit in Idaho?

Exempt — no permit or water right. Groundwater for domestic purposes up to 13,000 gpd is exempt from permitting; critical-area and moratorium closures generally target new PERMITTED (non-exempt) appropriations, so a household can still drill a domestic-exempt well even inside a critical groundwater area.

Which Idaho counties have groundwater restrictions?

25 Idaho counties sit in a managed, over-appropriated, adjudicated, or critically overdrafted groundwater basin — including Ada County, Bingham County, Blaine County, Bonneville County, Butte County. Each county profile cites the specific basin and rule.

Idaho · off-grid water rights

Water rights in Idaho

Whether a new off-grid home can legally get its own water in Idaho: the state well and water-rights rules, then the 25 counties where a specific groundwater basin adds a catch — each cited to the state water agency.

Idaho water rules

Household well
Exempt — no permit or water right
Groundwater for domestic purposes up to 13,000 gpd is exempt from permitting; critical-area and moratorium closures generally target new PERMITTED (non-exempt) appropriations, so a household can still drill a domestic-exempt well even inside a critical groundwater area.
Limit: 13,000 gpd (homes, stockwater, irrigation of ≤0.5 acre) under Idaho Code 42-227
Idaho Dept of Water Resources — Domestic Exemption ↗
Greywater reuse
permitted
Subsurface/mulch-basin irrigation case-by-case; IDEQ approval.
Greywater Action / EPA REUSExplorer ↗
Rainwater harvesting
unrestricted
No restrictions on rooftop collection.
NCSL ↗
Water rights
prior appropriation
Prior appropriation; small domestic and stock uses statutorily exempt.
National Agricultural Law Center ↗

25 constrained counties in Idaho

Over-appropriatedAda CountyCinder Cone Butte Critical Ground Water Area37
Over-appropriatedBingham CountyEastern Snake Plain Aquifer (ESPA) Ground Water Management Area49
Over-appropriatedBlaine CountyEastern Snake Plain Aquifer (ESPA) Ground Water Management Area52
Over-appropriatedBonneville CountyEastern Snake Plain Aquifer (ESPA) Ground Water Management Area69
Over-appropriatedButte CountyEastern Snake Plain Aquifer (ESPA) Ground Water Management Area40
Over-appropriatedCassia CountyEastern Snake Plain Aquifer (ESPA) Ground Water Management Area52
Over-appropriatedElmore CountyEastern Snake Plain Aquifer (ESPA) Ground Water Management Area60
Over-appropriatedFremont CountyEastern Snake Plain Aquifer (ESPA) Ground Water Management Area62
Over-appropriatedGooding CountyEastern Snake Plain Aquifer (ESPA) Ground Water Management Area30
Over-appropriatedJefferson CountyEastern Snake Plain Aquifer (ESPA) Ground Water Management Area47
Over-appropriatedJerome CountyEastern Snake Plain Aquifer (ESPA) Ground Water Management Area37
Over-appropriatedLincoln CountyEastern Snake Plain Aquifer (ESPA) Ground Water Management Area32
Over-appropriatedMadison CountyEastern Snake Plain Aquifer (ESPA) Ground Water Management Area70
Over-appropriatedMinidoka CountyEastern Snake Plain Aquifer (ESPA) Ground Water Management Area39
Over-appropriatedOneida CountyCurlew Valley Critical Ground Water Area53
Over-appropriatedOwyhee CountyGrand View-Bruneau Ground Water Management Area40
Over-appropriatedPower CountyEastern Snake Plain Aquifer (ESPA) Ground Water Management Area57
Over-appropriatedTwin Falls CountyEastern Snake Plain Aquifer (ESPA) Ground Water Management Area53
Actively managedBannock CountyMalad Valley Ground Water Management Area70
Actively managedBear Lake CountyBear River Ground Water Management Area66
Actively managedCaribou CountyBear River Ground Water Management Area69
Actively managedFranklin CountyBear River Ground Water Management Area62
Actively managedNez Perce CountyLewiston Plateau Ground Water Management Area74
ManagedBonner CountyRathdrum Prairie Ground Water Management Area70
ManagedKootenai CountyRathdrum Prairie Ground Water Management Area66

Keep exploring Idaho

See the full Idaho county ranking, compare states on the water-rights hub, or read how we score water access. We dim physical water — never erased — where a county sits in one of these basins, household-first.

General guidance, not legal advice. Off-grid, building, and land-use rules are often set at the county level and change often. Verify with your county and state before acting. Data reviewed 2026-06-26.