| St. Marks River | |
| Map: | Stmarksrivermap.png |
| Map Size: | 288px |
| Pushpin Map Size: | 288px |
| Subdivision Type1: | Country |
| Subdivision Name1: | United States |
| Subdivision Type2: | State |
| Subdivision Name2: | Florida |
| Subdivision Type3: | Counties |
| Subdivision Name3: | Leon, Jefferson, Wakulla |
| Subdivision Type4: | District |
| Subdivision Name4: | NWFWMD |
| Length: | 36miles |
| Discharge1 Avg: | 1122cuft/s |
| Discharge2 Location: | St. Marks River Rise |
| Discharge2 Avg: | 433cuft/s |
| Source1: | Tallahassee Hills |
| Source1 Location: | Capitola, Florida |
| Source1 Coordinates: | 30.4778°N -84.1003°W |
| Mouth: | Apalachee Bay |
| Mouth Location: | Port Leon, Florida |
| Mouth Coordinates: | 30.0814°N -84.1919°W |
| Basin Size: | 1150sqmi |
| Tributaries Left: | East River |
| Tributaries Right: | Lafayette Creek, Wakulla River |
The St. Marks River is a river in the Big Bend region of Florida. It has been classified by the Florida Department of Environmental Protection as an Outstanding Florida Water, and is the easternmost river within the Northwest Florida Water Management District.[1]
The St. Marks River begins in eastern Leon County, Florida and flows 36miles through Leon and Wakulla counties into Apalachee Bay, an arm of the Gulf of Mexico. It has a drainage basin of 1150sqmi[1] in size. It has one significant tributary, the Wakulla River.
A few miles south of its source the St. Marks passes under a natural bridge at Natural Bridge Battlefield Historic State Park and then disappears underground to become a subterranean river for about one-half mile. The river emerges at the St. Marks River Rise, a first magnitude spring with a discharge of 433cf/s,[1] to pass over a stretch of rocks, forming rapids.
The incorporated town of St. Marks is located at the juncture of the Wakulla and St. Marks Rivers. To the north is the community of Newport. Between St. Marks and Newport is a small industrial area serviced by barge.
The San Marcos de Apalache Historic State Park and St. Marks lighthouse are located near the mouth of the river, while the City of Tallahassee's Sam O. Purdom Generating Plant is located on the river in St. Marks.
| Crossing | Carries | Image | Location | Coordinates |
|---|---|---|---|---|
| Headwaters | 30.4778°N -84.1003°W | |||
| Valentine Road | Capitola | 30.4725°N -84.1011°W | ||
| CR 1568 Buck Lake Road | Capitola | 30.4636°N -84.1069°W | ||
| rail bridge | CSX Transportation | Capitola | 30.4442°N -84.1033°W | |
| CR 1540 Capitola Road | Capitola | 30.4433°N -84.1031°W | ||
| Confluence with Lafayette Creek | 30.4278°N -84.1047°W | |||
| US 27 Perry Highway | Chaires Crossroads | 30.4208°N -84.1014°W | ||
| CR 259 Tram Road | Cody | 30.3619°N -84.0608°W | ||
| ford | private road | 30.3283°N -84.0892°W | ||
| natural bridge | CR 2192 Natural Bridge Road | Natural Bridge Battlefield State Park | 30.2842°N -84.1506°W | |
| natural bridge | 30.2831°N -84.1508°W | |||
| George Nesmith Bridge | US 98 Coastal Highway | Newport | 30.1989°N -84.1781°W | |
| Confluence with Wakulla River | St. Marks | 30.1494°N -84.2111°W | ||
| Confluence with East River | 30.0886°N -84.1789°W | |||
| Mouth | 30.0814°N -84.1919°W | |||