St. Marys Intracoastal Gateway Marina.
Nassau River near St. Marys Intracoastal Gateway Marina.
About this river
Nassau River is an 18.6 mile river near St. Marys Intracoastal Gateway Marina. in Georgia. Streamflow is measured at the USGS gauge Nassau River near Tisonia, FL (site 02231291). The National Hydrography Dataset places it at stream order 5. Reach geometry comes from the USGS National Hydrography Dataset.
Typical flow by month
2013 to 2026
Nassau River typically runs highest in August, at a median 449 cfs, and lowest in October, at -27 cfs. The highest flow on record for any single day is 7,330 cfs, in 2024.
| Month | Typical (cfs) | Usual range (cfs) | Relative level |
|---|---|---|---|
| January | 160 | -451 to 688 | |
| February | 141 | -560 to 918 | |
| March | 149 | -669 to 928 | |
| April | 349 | -670 to 929 | |
| May | 145 | -753 to 749 | |
| June | 288 | -489 to 988 | |
| July | 366 | -293 to 941 | |
| August | 449 | -486 to 940 | |
| September | 199 | -848 to 975 | |
| October | -27 | -919 to 842 | |
| November | 49 | -891 to 785 | |
| December | 173 | -689 to 900 |
Typical is the median of each month’s daily median values, and the usual range runs from the median 25th to the median 75th percentile, across about 12 years of record. Statistics published by the US Geological Survey for Nassau River near Tisonia, FL (site 02231291). Conditions on any given day can fall well outside the usual range. Check the current reading before you go.
Boat access nearby
4 mapped launches sit in the mapped area of Nassau River, all of them public access. Ramp data comes from the USGS national boat-ramp inventory.
Embed this gauge on your site
Paste this snippet anywhere, an outfitter page, a club site, a trip report, to show Nassau River's live streamflow, water level and 7-day trend. It reads the USGS gauge directly, updates itself, and links back here.
See every free widget you can put on your site, including live conditions and a 7 day forecast.
