St. Lucie Estuary

The St. Lucie River is a 7-mile-long (11 km)estuary linked to a coastal river system in St. Lucie and Martin counties in the Florida, United States. The St. Lucie River and St. Lucie Estuary are an "ecological jewel" of the Treasure Coast, central to the health and well-being of the surrounding communities. The river is part of the larger Indian River Lagoon system, the most diverse estuarine environment in North America with more than 4,000 plant and animal species, including manatees, oysters, dolphins, sea turtles and seahorses.

Historically, the St. Lucie was a freshwater river with no connection to either the Atlantic Ocean or Lake Okeechobee. Beginning in the late 19th century, the river and its watershed underwent a series of modifications for navigation, flood control and water supply purposes.

The North Fork of the St. Lucie River flows south from St Lucie County into Martin County where it joins the north-flowing South Fork, which was once called the Halpatiokee River, just south of the old Roosevelt Bridge (Old Dixie Highway) in Stuart to form the main St. Lucie River. It then passes under the Florida East Coast Railway drawbridge and the new high-level Roosevelt Bridge (U.S. Route 1) and flows east with Rio on the north side and Stuart on the south until it reaches the northern end of the Sewall's Point peninsula, where it runs south under the Evans Crary Bridge to the end of Sewall's Point, where it flows into the Indian River Lagoon directly west of the St. Lucie Inlet which goes into the Atlantic Ocean. The entire river is accessible to Lake Okeechobee by the Okeechobee Waterway.

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