Research & ReferenceResearch & Reference
Original research, sourced datasets, and reference materials on water-well depth, permits, and groundwater. All pages are free, ungated, and cited to primary sources—federal agencies, state authorities, and peer-reviewed studies.
Research pages are not service pages. They contain no service request forms or commercial calls to action. The goal is accurate, reproducible reference material.
An estimated 20,494,449 U.S. housing units self-supplied their domestic water in 2020 — 14.6% of all housing units. This page puts the two strongest federal benchmarks side by side: the 2020 EPA ORD machine-learning model and the revised 2015 USGS county population series, for all 50 states, D.C., and all 67 Florida counties. Includes a downloadable original dataset with SHA-256 checksums.
Last verified July 23, 2026 · Dataset version 2026-07-23 · 51 states and D.C. + 67 Florida counties · CC BY 4.0
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The USGS overall median depth of domestic-supply wells in the conterminous United States is 142 feet. This page explains why no federal agency publishes a standardized 50-state average table, maps where each state's data lives, publishes an original 13-state provenance dataset (CSV, JSON, and data dictionary), and provides the protocol for producing a defensible state table.
Last verified July 23, 2026 · Dataset: Well-Record Provenance by State, 2026 Edition 1 · 13 states · CC BY 4.0
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