The palm-fringed Cayo Costa State Park is on an undeveloped barrier island that separates Charlotte Harbor from the Gulf of Mexico. © Russell Sparkman
Watershed Stats
Size of Basin: 857 square miles
Major Towns: Punta Gorda, Cape Coral, Sanibel, Englewood, South Venice, and Venice Gardens
Counties: Charlotte, Lee, and Sarasota
Major Water Features: Lemon Bay; Godfrey, Rock, Oyster, and Buck Creeks; Placida Harbor; Coral Creek; Charlotte Harbor Proper; Gasparilla Sound; Pine Island Sound; Tarpon Bay; Island Creek; Sanibel River; San Carlos Bay; Matlacha Pass; and Gator Slough Canal
Overview
Charlotte Harbor is recognized as Florida's healthiest estuary and a world-class sportfishing destination. © Russell Sparkman
Charlotte Harbor, in southwest Florida, is a semi-enclosed body of water open to the Gulf of Mexico through several tidal inlets. The harbor is America's 17th largest estuary and Florida's 2nd largest open-water estuary, with an open-water surface area of about 270 square miles and an average depth of seven feet. The harbor and its adjacent estuaries make up one of the most pristine and productive coastal ecosystems in the state of Florida. The harbor, which comprises Lemon Bay, Charlotte Harbor Proper, and Pine Island Sound, receives fresh water from three major rivers (Peace, Myakka, and Caloosahatchee) and several smaller streams that mix with the marine waters of the Gulf. Depending on the season, location, and depth in the harbor, salinity can range from zero to full-strength seawater.
The region is home to five national wildlife refuges, five state aquatic preserves, and one state buffer preserve. It supports a great diversity of semitropical plant and animal life. In 1995, Charlotte Harbor was recognized as an estuary of national significance and was accepted into the National Estuary Program. A remarkable feature of the region is that nearly all the wetlands surrounding the harbor are designated as state buffer preserves and are publicly owned. The following significant conservation areas found within or adjacent to the basin: Amberjack Slough Environmental Park (178 acres), Cayo Costa State Park (1,655 acres), Cape Haze Aquatic Preserve (11,284 acres), Cedar Point Preserve (88 acres), Charlotte Flatwoods Environmental Park (486 acres), Charlotte Harbor State Buffer Preserve/Cape Coral Unit (7,951 acres), Charlotte Harbor State Buffer Preserve/Cape Haze Unit (20,343 acres), Charlotte Harbor State Buffer Preserve/Pine Island Unit (6,474 acres), Charlotte Harbor State Buffer Preserve/Punta Gorda Unit (5,572 acres), Don Pedro Island State Park (132 acres), Gasparilla Sound/Charlotte Harbor Aquatic Preserve (79,168 acres), Gasparilla Island State Park (144 acres), Island Bay National Wildlife Refuge (20 acres), J.N. "Ding" Darling National Wildlife Refuge (5,550 acres), Lemon Bay Aquatic Preserve (7,667 acres), Matlacha Pass Aquatic Preserve (12,511 acres), Matlacha Pass National Wildlife Refuge (512 acres), Oyster Creek Environmental Park (135 acres), Pine Island National Wildlife Refuge (548 acres), Pine Island Sound Aquatic Preserve (54,176 acres), Sanibel-Captiva Conservation Foundation Lands (1,800+ acres), and Stump Pass State Park (245 acres).
Human Impacts
Pollutants from many sources including fertilizers used on residential lawns threaten the health of Charlotte Harbor Estuary. © Russell Sparkman
There are two main ecological issues in Charlotte Harbor proper. First, freshwater inflows to the harbor have been altered because of ground water over-pumping for irrigation and drinking water. Second, pollutants are being introduced from urban, industrial, and agricultural sources and from the harbor's tributaries, especially the Peace and Myakka Rivers. Of particular concern is Lake Hancock, a highly polluted lake at the headwaters of the Peace River that discharges nitrogen- and algae-laden water into Charlotte Harbor. Excessive nutrients (especially nitrogen) can stimulate the growth of algae, resulting in low oxygen levels that can cause fish kills. While the deeper waters of Charlotte Harbor may already be naturally hypoxic, the addition of nutrients and algae from upstream sources can only exacerbate the situation.
Although the lower portion of Charlotte Harbor occasionally suffers from reduced freshwater inflows, it is also periodically deluged with excess levels of nutrient-laden fresh water from urban and upstream agricultural canals that cause algal blooms and reduce dissolved oxygen levels. Of particular concern are flood control discharges from Lake Okeechobee via the Caloosahatchee River, which bring not only large quantities of fresh water, but also nutrients and algae into the southern portion of Charlotte Harbor. Submerged aquatic vegetation, oyster reef coverage, and bay scallop populations have been drastically harmed by these sudden, extreme salinity fluctuations and associated turbidity.
In the Lemon Bay area, the most urbanized portion of the Charlotte Harbor Basin, the development of residential communities has replaced many wetlands and marshes with open-water canals and filled uplands. Ecological concerns include the effects of boat traffic and dredging on the Intracoastal Waterway, the existence of dynamically unstable tidal inlets, the retention of mangrove stands, the protection of seagrass beds, and the growth of nuisance exotic vegetation. In deeper areas of the bay, nutrients from septic systems and stormwater runoff can cause algal blooms that reduce water clarity and cause seagrasses to die back.
In the Pine Island Sound area, the Cape Coral waterways directly influence the quantity and quality of freshwater inflow to Matlacha Pass and San Carlos Bay. Periodically, large freshwater releases from the Caloosahatchee River, caused by agricultural activities, adversely affect seagrasses, oyster beds, and other plants and animals. The development of residential communities and the presence of large areas of undeveloped lots have eliminated a significant portion of the area's wetlands and marshes by conversion into open-water canals and filled uplands.
In recognition of these impacts, Florida Department of Environmental Protection, the South Florida Water Management District (SFWMD), the Southwest Florida Water Management District (SWFWMD), and local governmental, scientific, educational, and citizen organizations are working to develop strategies for protecting and restoring water quality and quantity in the Charlotte Harbor Basin.
Interesting Facts:
- Charlotte Harbor is one of Florida's most popular sport fishing destinations and is home to one of the world's largest tarpon fishing tournaments.
- The American crocodile (Crocodylus acutus) is found in the waters of Pine Island Sound, the farthest point north that the species has been observed.
- Florida currently provides about 75 percent of the nation's phosphate supply and about 25 percent of the world's supply. Most of that phosphate comes from the Bone Valley deposit of more than 500,000 acres, which principally lies in the Peace River watershed, which in turn drains to Charlotte Harbor.
- The impacts of phosphate mining and chemical processing are of significant concern, especially to the downstream residents in Charlotte County, whose water supply (the Peace River) is directly affected by poor quality water occasionally discharged from mines and processing plants.
- Red tides are common in the Gulf of Mexico-Charlotte Harbor region. A particularly widespread red tide event was thought to be responsible for massive manatee mortality in 1996 in Charlotte, Lee, and Sarasota Counties, with 142 manatee deaths recorded.
- The land sales development that began in the 1950s dramatically and permanently changed the character and use of the region. The land was subdivided, canals were dug, and streets were paved. The platting removed thousands of acres from agricultural and other productive uses years in advance of when the land would actually be needed for housing. Many of the platted lots and streets still lie empty and overgrown.
Florida Department of Environmental Protection, Southwest Florida Water Management District, South Florida Water Management District, and local governmental, scientific, educational, and citizen organizations are working on numerous projects to restore and protect the Charlotte Harbor Basin.
Watershed Restoration Program
DEP has implemented a Watershed Restoration Program to identify "impaired" waters requiring Total Maximum Daily Loads (TMDLs) and develop plans to reduce pollution in rivers, lakes, and streams in the Charlotte Harbor Basin.
Additional Information:
DEP TMDL Program Website
DEP Charlotte Harbor Assessment Report
Cape Coral Spreader Waterway Restoration
In the late 1970s, the developer of Cape Coral entered into a Consent Order with the state that required the construction of two interceptor canals, or spreader waterways, to capture the waters from the upland canal systems and allow them to flow through wetlands before discharging into Matlacha Pass. Over time, however, several breaches developed that allowed the canal waters to discharge directly to the estuary. The restoration project, which began in 2002, will install structures to close off the direct discharges of water and restore the sheet flow that was originally intended.
Additional Information:
DEP Southwest Invasive Upland Plant Working Group, 2004-05 Report (PDF)
Charlotte Harbor Aquatic Preserves
The preserves consist of 165,000 acres of submerged resources in five individually named preserves in Sarasota, Charlotte, and Lee Counties: Cape Haze Aquatic Preserve, Gasparilla Sound-Charlotte Harbor Preserve, Matlacha Pass Aquatic Preserve, Pine Island Sound Aquatic Preserve, and Lemon Bay Aquatic Preserve. All of these waters are also designated as Outstanding Florida Waters (OFWs). The management plans developed for each preserve focus on the general conditions and management needs for habitats and species, with special emphasis on resource management, research, and education.
Additional Information:
DEP Charlotte Harbor Aquatic Preserves Website
Charlotte Harbor Estuaries Volunteer Water Quality Monitoring Network
Through the network, 75 volunteers monitor water quality once a month at 35 to 40 sites throughout the Charlotte Harbor National Estuary Program's (CHNEP) Aquatic Preserve Estuaries.
Additional Information:
Charlotte Harbor Estuaries Volunteer Water Quality Monitoring Network Website
Charlotte Harbor Fisheries-Independent Monitoring Program
The program, conducted by the Florida Marine Research Institute (FMRI), a division of the Florida Fish and Wildlife Conservation Commission, is currently carrying out surveys in six estuaries statewide, including Charlotte Harbor. Data from the surveys provide estimates of the relative abundance of many economically and recreationally important species and are used to predict the availability of a species in the near future. The information is also used to determine what fisheries management measures are needed and to assess the effectiveness of those measures.
Additional Information:
FMRI Saltwater Fisheries Research Website
Charlotte Harbor National Estuary Program (CHNEP)
A partnership of citizens, elected officials, resource managers, and commercial and recreational resource users, CHNEP was established in 1995 to provide long-term protection for the larger Charlotte Harbor Basin. A Comprehensive Conservation and Management Plan (CCMP) is being implemented to preserve and restore this complex ecosystem.
Additional Information:
CHNEP Website
Charlotte Harbor State Buffer Preserve
The preserve, which consists of 46,195 acres of uplands in Charlotte and Lee Counties, is being acquired to provide an upland buffer between developable areas and the waters of the Charlotte Harbor Aquatic Preserves. The program's primary goals are to conserve and preserve natural ecological values and systems, protect archaeological and historical resources, and enhance the public appreciation of natural resources. A management plan was adopted in 1997.
Additional Information:
SWFWMD Charlotte Harbor State Buffer Preserve Guide (PDF)
Charlotte Harbor Surface Water Improvement and Management (SWIM) Plan
Completed in 1993 and updated in 2000, the plan outlines a series of research and/or restoration projects to protect and restore water quality, water quantity, and habitat in the Charlotte Harbor Basin.
Additional Information:
SWFWMD Charlotte Harbor SWIM Plan (PDF)
Comprehensive Everglades Restoration Plan (CERP)
The Central and Southern Florida (C&SF) Project was first authorized in 1948 to provide flood control, water control, water supply, and other services to the area that stretches from Orlando to Florida Bay. Although the project has performed its intended purposes well, it has also contributed to an unintended decline in the south Florida ecosystem. The purpose of the C&SF Project Comprehensive Review Study (the Restudy), conducted by the U.S. Army Corps of Engineers (USACOE) and SFWMD, was to modify the C&SF Project to improve the quality of the environment. The Restudy resulted in the 1999 publication of the Final Integrated Feasibility Report and Programmatic Environmental Impact Statement, now known as CERP. The activities associated with the Restudy and restoration plan will affect the Caloosahatchee River, which flows into the Pine Island area of the Charlotte Harbor Basin. Several projects will address the distribution of water from Lake Okeechobee to Charlotte Harbor.
Additional Information:
CERP Southwest Florida Feasibility Study Website
CERP Website
Environmental Impact Study (EIS)
In 1997, the Jacksonville District of the USACOE initiated an EIS for parts of Lee and Collier Counties, assisted by the Alternatives Development Group, made up of people from diverse backgrounds, including proponents of development, agriculture, and conservation. It also received help and advice from representatives of federal, state, and local governments, as well as citizens. Future USACOE permitting decisions in the study area will consider the stewardship of wetlands and cumulative impacts.
Additional Information:
Federal Register Notice of Intent
Lee County Conservation 20/20 Land Acquisition and Stewardship Program
In 1996, voters approved a referendum to fund the purchase of environmentally sensitive lands to be placed in public trust for preservation. The Board of County Commissioners subsequently created the Conservation 20/20 Program to acquire, preserve, and restore environmentally critical or sensitive lands in Lee County. As of March 31, 2002, $47.50 million had been spent to acquire 40 parcels of land totaling 7,550 acres.
Additional Information:
Lee County Conservation 20/20 Brochure (PDF)
Lower Charlotte Harbor Surface Water Improvement and Management (SWIM) Plan
In 2003, the SFWMD Governing Board designated Lower Charlotte Harbor a priority SWIM waterbody. A Reconnaissance Report, completed in 2006, was used as the primary resource to develop a draft Lower Charlotte Harbor SWIM Plan.
Additional Information:
SFWMD Lower Charlotte Harbor SWIM Plan (PDF)
Lower West Coast Water Supply Plan
This state-required regional water supply plan by the SFWMD serves as a guide for addressing future water demands in southwest Florida. The plan establishes a framework for future water use decisions for the Lower West Coast (LWC) Planning Area.
Additional Information:
SFWMD LWC Water Supply Plan, 2005-06 Update
Sanibel-Captiva Conservation Foundation (SCCF)
The foundation, established in 1967 by a group of concerned citizens, is dedicated to the preservation of natural resources and wildlife habitat on and around Sanibel and Captiva Islands.
Additional Information:
SCCF Website
Southwest Florida Feasibility Study
The SFWMD/USACOE study was born out of the C&SF Project Comprehensive Review Study's (the Restudy) recommendations for the C&SF Project to Congress in 1999. The Restudy recommended a feasibility study to identify southwest Florida's water resource conditions and to develop potential solutions to problems.
Additional Information:
CERP Southwest Florida Feasibility Study Website