Magothy Aquifer Fossil Water — Long Island
Deep Magothy aquifer beneath Long Island, the primary water supply for over 2.5 million people. Cretaceous-age sand and gravel formation with fossil water in the deepest confined sections. Shallow zones receive modern recharge, but the deep Magothy contains pre-Holocene water.
Overview
Deep Magothy aquifer beneath Long Island, the primary water supply for over 2.5 million people. Cretaceous-age sand and gravel formation with fossil water in the deepest confined sections. Shallow zones receive modern recharge, but the deep Magothy contains pre-Holocene water.
Additional Notes
USGS Long Island aquifer system study. Sole-source aquifer designation by EPA.
Water Source Data
Water Intelligence Score Breakdown
Total: 80/100Risk Assessment
Source depletion probability
Rights & regulatory exposure
Contamination & ecosystem risk
Geological Intelligence
Formation & aquifer contextHigh porosity — shallow, rechargeable aquifer
Ancient water, no modern recharge — non-renewable on human timescales
Land Details
PrivateWater Rights
UnverifiedRiparian Rights
Tied to land adjacent to water
Landowners with property bordering a watercourse have the right to reasonable use of the water. Rights are inseparable from the land itself.
- Attached to land with water frontage
- Cannot be sold separately from the land
- Subject to "reasonable use" doctrine
- Shared equitably among riparian owners
Disclaimer: Water rights information is provided for research and informational purposes only and does not constitute legal advice. Rights status, seniority, transferability, and enforceability vary by jurisdiction and change over time. Always consult a licensed water rights attorney and verify status with the relevant state water resources agency before any acquisition or use decision.
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Location
Data Sources & Attribution
Updated Apr 5, 2026Data is sourced from public and authoritative providers. Hi3 Water aggregates, normalizes, and scores records but does not assert ownership of underlying source data. Always verify critical details with the primary source before any decision.