Prior to the 1900s, the greater Everglades ecosystem flowed freely from the Kissimmee Valley to Lake Okeechobee and continued south to Florida Bay. This shallow sheet of water covered thousands of miles and was home to a complex system of plant life as well as a wide range of animal life. However, the Everglades of the 1800s was not the revered American treasure that we consider it today. During the late 1800s, settlers and land developers began to drain the Everglades to make the area more conducive to development. Attitudes were different, and the draining was a noble undertaking welcomed by local residents who were fearful of flooding.
Their fears were later justified. Damaging hurricanes in the 1920s and 1940s created a cry for help from residents. Congress responded with legislation for the Central and Southern Florida (C&SF) project, which provided the much needed flood protection. For many years, the C&SF project performed its intended functions well, but with many unintended and detrimental effects. Today, roughly half of the original Everglades no longer exists. While restoring the Everglades to its original majestic splendor is not possible, the Comprehensive Everglades Restoration Plan (CERP)—another noble undertaking—aims to save the Everglades and reverse some of the C&SF project’s unforeseen effects.
CERP includes many elements termed “foundation projects,” which are not among the 68 components that make up the plan, but do provide a critical piece of the larger CERP puzzle. One such project, located at the far downstream end of the C&SF project, is the Canal-111 (C-111) South Dade County project. C-111’s drainage basin includes approximately 100-mi2 of agricultural land located in the Homestead-Florida City area, as well as the entire Taylor Slough basin located within Everglades National Park (ENP). C-111 discharges into Florida Bay at its downstream end and to the north into Taylor Slough.
In the late 1950s, local interests in southern Dade County requested the C&SF project be modified to provide an adequate system of canals to provide drainage for urban development, which would include water control structures to prevent over-drainage of agricultural lands and contamination of groundwater by saltwater intrusion. The Flood Control Act (FCA) of 1962 authorized a project for southern Dade County to remove 40 percent of the standard project flood runoff from the drainage area, to reduce depth and duration of larger floods and to provide water control to prevent over-drainage of the area. To accomplish this, the plan provided for gravity drainage of the South Dade area by a primary system of 12 canals, including C-111, and the necessary outlets to serve a system of secondary canals proposed by local interests.
Local interests were responsible for constructing and maintaining lateral drainage facilities, as necessary, to realize the benefits made available by the federally-authorized project improvements. The plan recommended in the 1962 FCA was reviewed in the 1963 General Design Memorandum for South Dade County and was modified to reconcile the desires and interests of ENP, local interests and land developers. The proposed plan required the construction of L-31N and L-31W and their borrow canals for a distance of 21 miles, extending south from the existing part of L-31N to a point 1.5 miles south of State Road 27. The purpose of the L-31N and L-31W canals and levees was to protect the South Dade County area from overflow from the west and to provide water supply to the ENP.
In 1962, the Everglades National Park-South Dade Conveyance System was authorized by the 1968 Flood Control Act (FCA). Modifications in the plan included enlarging existing canals such as C- 111 to permit supplemental water supply from Water Conservation Area 3A to South Dade County and ENP.
Environmental concerns caused construction to be discontinued before all authorized project features recommended in the 1962 FCA were completed. In 1970, Congress enacted PL 91-282, which prescribed a monthly schedule of minimum water deliveries that must be provided to ENP from the C&SF project. Further studies were conducted from 1983 through 1988 to complete the authorized plan of improvement for flood control, environmental enhancement and water management in the C-111 basin. However, from 1988 to 1990, several events changed the scope and schedule for completion of the C-111 report.
Congress, recognizing the significance of ENP and the adverse effects on the park from external factors, directed the Secretary of the Army to take all feasible measures consistent with the purposes of the C&SF project to protect natural values associated with ENP. This included the analysis, design and engineering associated with completion of works and operations in the C-111 basin area of the east Everglades. Additional studies were done from 1989 to 1994 and modifications recommended, but in 1999 the U.S. Fish and Wildlife Service found that operations of systems would adversely affect the Cape Sable Seaside Sparrow, an endangered subspecies native to the area. Ultimately, an Interim Operational Plan was put into place, the final phase of which is now underway.
In August 2007, a groundbreaking ceremony was held to kick off a phase of the C-111 project, Contract 7, that had been delayed due to land acquisition and environmental interests. This phase of the project will finalize the Interim Operational Plan for the levees connecting S-332B West Detention Area to S-332D High Head Cell and will build a culvert structure. The contractor, Atlantic Civil, was given notice to proceed on Contract 7 in July 2007. The contractor has prepared the borrow areas, backfilled L-31W, and has started levee construction. The work is on schedule to be completed in January 2008.
The next phase of the C-111 project, Contract 8, is expected to be awarded in January 2008 and will include constructing the North Detention Area that runs from Structure 332B north to the 8.5-mi2 stormwater treatment area, western overflow weirs for the north and south Detention Areas, and the north and south Detention Areas flowway berm.
The C-111 South Dade project is expected to be completed in 2012. When complete, the project will provide modifications to the current water management system that will ultimately restore significant hydrologic flow to the Everglades.