Water bodies, watersheds and storm water
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Upper St. Johns River Basin Home
Canal 1 rediversion project
Fellsmere Water Management Area
Understanding flooding: The upper basin project and Canal 54
Upper St. Johns River Basin
Florida’s longest river begins its 310-mile northerly journey to the sea from a drainage basin west of Vero Beach in Indian River County. The 2,000-square-mile basin — the St. Johns River’s headwaters — has undergone significant changes during the 20th century that necessitated a massive flood control and wetland restoration project, which is nearly complete.
The Upper St. Johns River Basin, extending from the headwaters of the St. Johns River in Indian River and Okeechobee counties to the confluence of the St. Johns and Econlockhatchee rivers in Seminole County, originally contained more than 400,000 acres of floodplain marsh.
By the early 1970s, 62 percent of the marsh had been drained for agricultural and flood control purposes. Canals were constructed to divert floodwaters from the basin to the Indian River Lagoon. Impacts included a loss of water storage areas, diminished water quality, excessive freshwater going into the Indian River Lagoon, and significant decreases in fish and wildlife populations. The marsh that remained was further degraded by hydrologic alterations and nutrients in agricultural runoff.
Fort Drum prairie
In response to flooding problems in the basin, a highly structural federal flood control project was started in the 1960s but was halted because of potential environmental harm. During the late 1980s, this project was transformed into the upper basin project, co-sponsored by the St. Johns River Water Management District and the U.S. Army Corps of Engineers (USACE).
The upper basin project is a semistructural system of water management areas (WMAs), marsh conservation areas (MCAs), and marsh restoration areas covering approximately 166,500 acres in Indian River and Brevard counties. The system is designed to reduce damage from floods, improve water quality, reduce freshwater discharges to the Indian River Lagoon, provide for water supply, and restore or enhance wetland habitat.
Cypress swamp
Stick Marsh
Slough
History
The Upper St. Johns River Basin Project is a model of modern floodplain management — balancing the needs of a river with those of the people and creatures who depend on it. The project includes more than 150,000 acres of pristine and restored freshwater marshes that are now preserved for future generations.
In the early 1900s, thousands of floodplain acres in the headwaters of the St. Johns River — the upper basin — were diked and drained to create fertile farmlands. Devastating hurricanes in the 1920s and 1940s demonstrated the need for improved flood protection. The resulting flood control projects of the 1950s and 1960s proved harmful to the environment. Now in the final stages of completion, the upper basin project balances environmental needs with the need for reliable flood protection.
Resurrecting the upper basin
Starting in the 1950s, the U.S. Army Corps of Engineers (Corps) began planning a flood control project in the Upper St. Johns River Basin. The original upper basin project involved a series of flood storage reservoirs along the ridge, west of the St. Johns River, in Osceola and Orange counties. The project also included a network of canals to divert excess floodwaters from the upper St. Johns to the Indian River Lagoon. Portions of this flood control project, including Canal 54 (C-54), were constructed by 1973, when project construction was halted by President Richard Nixon due to an Environmental Impact Statement which found that the project had unacceptable impacts on the environment. One of the environmental impacts that doomed the original upper basin project was the harm that freshwater diversion caused to the lagoon (a body of salt water).
C-54 was originally designed to divert up to 6,000 cubic feet per second (cfs) of water from the St. Johns River to the Indian River. Environmental studies found that this diversion of freshwater would significantly reduce the population of shellfish in the Indian River, harming the commercial shell fishing industry. In addition, the large volume of freshwater diversion would cause big swings in the salinity of the lagoon, impacting other fish and wildlife resources in that water body. The loss of freshwater in the St. Johns River was found to adversely impact wildlife and threatened the use of the river for public water supply.
Warbler
Cypress tree
Wood stork
In the mid-1970s, the flood control project was stopped and Florida withdrew its sponsorship because of environmental concerns.
In 1977, the District took over the project area and designed an innovative plan with USACE to revitalize the river’s flow by reclaiming drained marshlands, plugging canals and building reservoirs. Water control structures and new construction have been kept to a minimum. Dikes have been fortified and agricultural drainage routes have been re-directed to improve water quality and enhance the marsh. The result is a flood protection strategy that relies on a more natural, “semi-structural” approach. That strategy continues as part of the Surface Water Improvement and Management plan for the basin. Under maximum storm conditions, the project is designed to hold 500,000 acre-feet of water — enough water to cover the 200,000-acre project with an average of 2.5 feet of water.
The final component of the upper basin project is under way. In February 2007, USACE announced that funds were available to complete construction of the Three Forks Marsh Conservation Area.
The Three Forks component will include new levees, flow-ways and an outfall structure to move water across the 13,737-acre marsh conservation area. Water discharged from the St. Johns Water Management Area into Three Forks will also begin to fill the greatly anticipated Lake Lawton Recreation Area, a 7,000-acre lake and park west of the city of Palm Bay.
When the Three Forks component is completed, the Upper St. Johns River Basin Project will be substantially finished, providing many benefits to the people and wildlife that depend daily on the remote headwater marshes of the upper St. Johns River.
The historic floodplain, once reduced to a mere ghost of its former self, is flourishing.
The sheer scope of the upper basin project requires ongoing teamwork among USACE, the District and other state environmental agencies and interest groups. To meet the project’s land requirements, the District has acquired real estate at fair market value. USACE performs the engineering design and manages construction of the project. Operation and maintenance of the upper basin lies with the District.
More than just flood control
Water from nearby citrus groves and livestock pastures is now discharged into large reservoirs called water management areas, which keep agricultural runoff isolated from water that recharges the marsh. This runoff water can be reused for farm irrigation and freeze protection. Water preserved in large marsh conservation areas improves the river’s hydrology and is available to maintain flows downstream. The upper basin project is much more than just flood control at work. The river’s headwaters are once again a broad, marshy expanse. Water is cleansed as it sheetflows across the vast floodplain marshes. Lost habitats are being restored, and fish and wildlife are returning.
Endangered wildlife species, such as the Everglades kite and the wood stork, are relocating to the area. Water quality is improving. A valuable shellfishery in the lagoon estuary is safeguarded because of the reduction of freshwater inflows from the St. Johns River. Recreational opportunities are emerging as the St. Johns River regains its status as a world-class fishery.
What it all means
The Upper St. Johns River Basin Project — one of the largest and most ambitious wetland restoration projects in the world — is giving new life to the river’s headwaters. The design of the project is on the cutting edge of environmental restoration technology. The project demonstrates a new level of compatibility between flood control and environmental protection. It shows that working with nature is often preferred to working against her. It also shows how two agencies have joined together to give nature a second chance.
Contact information
For additional information on the upper basin project, contact Hector Herrera, program manager, at (386) 329-4377 or hherrera@sjrwmd.com.
Updated on 6-2-2010
