St. Johns River

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St. Johns River
Origin St. Johns Marsh
west of Fellsmere, Florida
Mouth Atlantic Ocean
at Mayport, Florida
Basin countries United States
Length 310 mi (500 km)
Source elevation 24 ft
St. Johns River, near Blue Spring State Park
St. Johns River, near Blue Spring State Park
Entrance to Blue Spring State Park from the St. Johns River
Entrance to Blue Spring State Park from the St. Johns River
Map of the St. Johns River in 1876
Map of the St. Johns River in 1876

The St. Johns River (officially Saint Johns River, but commonly spelled St. John's River) is the longest river in the U.S. state of Florida, stretching 310 miles (500 km) from Indian River County to the Atlantic Ocean in Duval County. The St. Johns River is the third largest Northern flowing navitable River in the world, with the other two being the Nile and the Amazon. It was designated as one of the American Heritage Rivers in 1997 and pegged by an environmental organization as the 6th Most Endangered River in America in 2008. [1].

The elevation change from headwaters to mouth is only about 30 feet, making the St. Johns one of the world's "laziest" rivers[1]. Its extremely low velocity, combined with the generally level elevation, causes the St. Johns to spread out to a great width for much of its course. During periods of low flow, the river can be influenced by tides as far south as Lake Monroe - 161 miles inland[1]. For a distance of over twenty miles before arriving at downtown Jacksonville, the river's average width exceeds two miles and in some places exceeds three miles in width. The slow flow of the St. Johns makes it difficult for pollutants to be flushed from the waters, which has become a serious problem for the river ecosystem[1]. Still, the river is home to numerous species of plants and animals. It is not uncommon to see dolphins in the river east of Jacksonville and manatees in the springtime when the water warms up. Alligators, bald eagles, ospreys, stingrays, and many species of fish—both salt and fresh water—are found living in the river and on its banks. The entire basin is managed by the St. Johns Water Management District.

Contents

History

Thousands of years ago, the area of land that now comprises the river was connected to the Atlantic Ocean for most, if not all, of its length, making the river nothing more than an extended system of lagoons and tributaries. As the ocean levels dropped, barrier islands and reef formations effectively walled off the system of lagoons from the ocean, forming the river. This unusual geologic past explains why a river of this size arose with such little drop in elevation from source to mouth (30 feet over 310 miles).

The river basin was the home to the native Timucua tribes, who called it Welaka, or "river of lakes". In the early 16th century, Spanish explorers called the river Río de Corrientes, or "river of currents".

An expedition of French Huguenots landed at the mouth of the river on May 1, 1562, and thus called it "Rivière du Mai", or "May River". In 1564, a bluff overlooking this site (St. Johns Bluff) became the location of Fort Caroline, the first French colony in North America. This fort was captured by the Spanish from St. Augustine a little over a year after it was founded.

The conquering Spanish renamed the river (and the fort) "San Mateo", after Saint Matthew, whose feast day was the day after their victory over the French.

A Catholic mission named San Juan del Puerto was founded on Fort George Island near the river's mouth around 1578, and in time the river came to be known as "Río de San Juan". This was translated St. Johns River in English, and this name has remained intact through colonization, war, and the creation of the United States.

During the American Civil War, control of the river was decided at the Battle of Saint John's Bluff, enabling the Union Army to firmly establish control over Jacksonville.

Geography

The upper (southern) basin of the river has indistinct banks, with numerous sloughs and lagoons, often pooling into ponds and lakes. Some of the larger lakes are Blue Cypress Lake, Lake Hellen Blazes, Sawgrass Lake, Lake Washington, Lake Winder, Lake Poinsett, Ruth Lake, Puzzle Lake, Lake Harney, Lake Jesup and Lake Monroe.

Below Lake Harney, the river is joined by the Econlockhatchee River and runs between higher bluffs on either side, forming the middle basin. This part of the river runs through what is now the Ocala National Forest. After the English acquisition of Florida from Spain in 1762, English explorer William Bartram was sent by King George III to explore the territory. In his subsequent book Travels, Bartram called the middle basin a "...blessed land where the gods have amassed into one heap all the flowering plants, birds, fish and other wildlife of two continents in order to turn the rushing streams, the silent lake shores and the awe-abiding woodlands of this mysterious land into a true garden of Eden." Here the river forms the broad and shallow Lake George, where marine sharks have been seen in drought years in which the normally rain-fed freshwaters of the river cannot fight back the inflowing Atlantic salt water.

The lower (northern) basin begins where the largest tributary of the St. Johns, the Ocklawaha River, joins the flow. (Both rivers are part of the modern Caravelle Ranch Wildlife Management Area.) It passes through Palatka, then through unspoiled riverine bottomland hardwoods, pine flatwoods and sandhill communities, on its way to Jacksonville.

Past Green Cove Springs, the river becomes an estuary, where fresh and salt water meet, and a wide diversity of living species inhabit the islands, inlets, sounds, streams and marshes of the area.

Tributaries

Starting at the river's mouth and moving upstream, major tributaries of the St. Johns River include Pablo Creek, the Trout River, the Arlington River, the Ortega River, Doctors Lake, Julington Creek, Black Creek, the Cross Florida Barge Canal, the Oklawaha River, the Wekiwa River, Lake Jessup, and the Econlockhatchee River. Fort Drum Creek drains into the St. Johns Marsh, the source of the river.[2]

Fishing

The St. Johns is known for excellent fishing, especially largemouth bass. Its estuarial nature provides both freshwater and saltwater or brackish-water species. Saltwater species include redfish, flounder, tarpon, and the brackish water sea trout, known locally as the "gator trout". A recent report states that saltwater species have been venturing farther up the river (southwards) in recent years.

Some of the best known fishing occurs in January–March, when the American shad run up the river, and it becomes full of trolling boats. The shad, like the salmon, are anadromous and live most of their life at sea. They are caught primarily for the eggs, shad roe, since the flesh is below average and full of small bones.

Map of Downtown Jacksonville showing three of the five road bridges that cross the St. Johns downtown; in total, seven bridges cross the St. Johns within the city of Jacksonville
Map of Downtown Jacksonville showing three of the five road bridges that cross the St. Johns downtown; in total, seven bridges cross the St. Johns within the city of Jacksonville

Port city of Jacksonville

Main article: Jacksonville, Florida

As the St. Johns River flows through the city of Jacksonville it is spanned by seven bridges. The Jacksonville Port Authority (JAXPORT) facilities at the mouth of the St. Johns River make up Florida's second largest port. In fiscal year 2003, JAXPORT handled over 1,500 ships, delivering almost 700,000 containers and over 500,000 cars. Some of the major local commodities include gypsum and oil.

The United States Navy maintains the Naval Air Station Jacksonville south of downtown and Naval Station Mayport near the river's mouth.


Wildlife gallery

See also

References

  1. ^ a b c "St. Johns River Fast Facts". Retrieved on 2007-01-11.
  2. ^ DeLorme Florida Atlas & Gazetteer, 2003 edition

External links

Wikipedia content modification information:

  • This page was last modified on 4 September 2008, at 21:52.

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