Methodology & Data Sources

Open/closed status for every ramp comes directly from the U.S. Army Corps of Engineers (USACE) Savannah District's own public Status of Corps Boat Ramps page. USACE is the source of truth here — we don't infer or calculate status ourselves.

We check that page twice a day and record what we see, timestamped at the moment we checked it. That page doesn't publish its own last-updated time, so "last checked" on this site means when we looked, not necessarily when USACE last changed the status.

Lake Hartwell's elevation comes from the USACE CWMS (Corps Water Management System) Data API, reading the hourly gauge feed for Hartwell Dam.

We check this feed every 2 hours. The elevation shown is the most recent reading available at that check — every ramp and water-level page on this site shows the same timestamped reading and observation time, so you're never comparing a fresher number on one page against a staler one on another.

If the USACE feed is temporarily unavailable, we keep showing the last known good reading and mark it stale rather than showing a blank or zero value.

The "approximate lake elevation when a ramp becomes unusable" figures come from USACE Savannah District — Hartwell Lake Boat Ramp Elevations, dated July 13, 2021. This is a static reference document, not a live feed — we don't re-scrape or re-derive it automatically.

These are approximate planning references, not guarantees. USACE's own document describes them as approximate, and actual usability can vary based on siltation, sediment buildup, physical ramp condition, and your specific trailer geometry, vehicle, and boat.

We deliberately do not calculate or display an exact "X feet until this ramp closes" figure. Doing that responsibly would require resolving a vertical-datum question between this document and the live water-level feed that we haven't fully verified, and even then it would overstate precision this data doesn't support.