Water provides Lee County with an environment and quality of life that lures new residents and visitors alike. Human activities, population growth, and watershed alterations, though, have caused significant impacts to the County’s water and other natural resources.
In this multipart story, we will take you on a tour of the watershed, discussing the problems and causes as well as the steps the county and partner agencies have taken to help improve our local water quality. The county can’t do this alone so we also share some ways you can help keep our local waters clean and safe for us, and our future generations.
Lee County is home to all or part of several major waterbodies, including the Caloosahatchee River, Estero River, Imperial River, Pine Island Sound, San Carlos Bay, Charlotte Harbor, and the Gulf of Mexico in addition to many smaller tributaries.
1) Gulf of Mexico
The Gulf of Mexico is the largest gulf in the world, encompassing over 600,000 square miles. It is an ocean basin that is bounded by five U.S. states as well as Cuba and part of Mexico.
The Gulf is one of the water features that makes Lee County a great place to live, work and vacation. But it is more than a grand waterbody with beautiful beaches – it is a vibrant ecosystem with an exciting history and a vital commercial role.
2) Lee County Bays and Estuaries
An estuary is where fresh and saltwater mix; where river waters meet the sea. A Bay is a type of recessed coastal water body that directly connects to a larger waterbody such as the Gulf of Mexico.
Two rivers, the Imperial River and Estero River, bring freshwater into Estero Bay, an estuary that was designated as the state’s first aquatic preserve.
The Charlotte Harbor Estuary has a very large watershed: is mostly located within Charlotte County, but approximately one third of this estuary lies within Lee County.
San Carlos Bay is located at the mouth of the Caloosahatchee River. It connects to Matlacha Pass to the north, and Pine Island Sound to the west.
3) Caloosahatchee River and Estuary
The Caloosahatchee River and Estuary is another west coast treasure, and its health is essential to the Lee County way of life.
The river flows west-southwest from Lake Okeechobee to the Gulf of Mexico, becomes a tidal estuary within Lee County, and broadens as it nears the Gulf.
Extensive historical modifications to the Caloosahatchee River and its watershed have altered the hydrology of the region. As a result, heavy rainfall can bring large influxes of fresh water into the Caloosahatchee Estuary from stormwater runoff within the basin, Lake Okeechobee releases or both. The increased freshwater flows affect salinity levels and water quality in the estuary, potentially causing environmental harm (SFWMD).
Lake Okeechobee means “big water” in the Seminole Indian language, and with a surface area of 730 square miles, the lake is the liquid heart of South Florida. In fact, Lake Okeechobee is only slightly smaller than the entire land area of Lee County!
Lake Okeechobee provides water for people, farms and the environment, and habitat for fish, birds, and other wildlife. The lake’s health has also been affected by human influences, but restoration efforts are underway here too. The Caloosahatchee River starts at Lake Okeechobee.
Through this story map, we explore water quality issues that the County has been actively working to manage, explain some of their causes, highlight steps Lee County is taking to address water quality and provide useful tips that residents and visitors alike can use to help us save this most valuable resource.
Our region is characterized by a marked seasonality that offers different water quality challenges at different times of the year.
The dry season - from November to May - brings seasonal population growth, and with that comes an increase in the impacts to local water quality from additional fertilizers, septic tank use, traffic, and other factors.
Lee County’s rainy season lasts from about June through October, and supports aquifers, agricultural activities, fish and wildlife populations as well as the growing water demand from communities throughout our area. The stormwater run-off at this time of the year is at its annual high. Increases in the concentrations of pollutants like nitrogen and phosphorus to the estuary can destroy the natural balance and even fuel algae blooms.
In aquatic systems, when there is an overload of nutrients, opportunistic species take advantage of this issue to rapidly grow into blooms. These species can cause the famously known blue-green algae, red tide and red drift algae phenomena and the eutrophication of fresh water ecosystems.
Blue-green algae, or “cyanobacteria,” are bacteria but, like plants, use sunlight to grow. They are ubiquitous in aquatic ecosystems. They play an important role in the environment, as part of the natural nutrient cycles and the food chain.
Blue-green algae thrives in warm waters with a high nutrient content. When the environment is conducive and they have the resources to grow out of control, they will become a bloom.
This can deplete the oxygen in the water, which can cause fish kills.
Some blooms can also produce toxins. In their toxic form, it can cause illness in humans, pets, waterfowl, and other animals that come in contact with it.
Red Tide produces a potent toxin, when red tide blooms are bad enough, it kills fish
Florida's red tide is a natural occurrence that begins offshore. It was first recorded in the 1800s. If the bloom moves inshore, nutrient runoff from land may promote bloom expansion.
A bloom can linger in coastal areas for days, weeks or even months. Red tides occur when microscopic algae multiply to higher than normal concentrations, often coloring the water to red or brown hues.
The most common species of red tide in our coasts is Karenia brevis. Its toxins, which can cause health problems in humans, are capable of killing fish, birds and other marine animals.
Red Drift Algae
Red drift algae is also influenced by nutrients.
This type of algae is visible with the naked eye. It is common for them to detach from the bottom and wash up along beaches in small amounts.
On occasions, if there is an excess of nutrients in the water, they will bloom. If the currents and tides are favorable, they may wash up on the shore in huge quantities.
Although it does not release toxins, the piles of algae will decay after a few days and they will emit an unpleasant odor until removed or washed away.
Aquatic Plant Overgrowth
Aquatic vegetation is essential for fresh water ecosystems. They produce oxygen in the water, remove nutrients, and serve as a source of food and shelter for aquatic organisms.
An excess of nutrients in the water can make plants overgrow to levels that are harmful for their ecosystem.
This is especially true for invasive exotic species that are capable of growing at a high rate and take over the ecosystem. When they are out of control, they can even deplete the dissolved oxygen in the water.
Next issue, we will discuss causes in dept and what Lee County is doing about it.