Advertisement

You will be redirected to the page you want to view in  seconds.

The Sanibel River
The Sanibel River: Naturalist Mark "Bird" Westall talks about the Sanibel River(Video by Andrew West/news-press.com)
Naturalist Mark 'Bird' Westall works for the city of Sanibel to remove cattails from the Sanibel River to reduce nutrients. / Andrew West/news-press.com
An osprey flies off with a meal over the Sanibel River. The river is home to many kinds of birds and wildlife. / Andrew West/news-press.com
The Sanibel River is considered impaired for nutrients, which can cause algal blooms, leading to low levels of dissolved oxygen. Sanibel is looking for ways to reduce the nutrients. / Andrew West/news-press.com
Mark 'Bird' Westall, a naturalist and operator of Canoe Adventures on Sanibel, tours the Sanibel River recently. / Andrew West/news-press.com
The 265-acre Sanibel Gardens Preserve, which is owned by the city of Sanibel and the Sanibel-Captiva Conservation Foundation, straddles the Sanibel River. It was restored in 2005. / Andrew West/news-press.com

More

Interactive: The Sanibel wetlands

• • •

At the mere mention of the Sanibel River, Sterling Fulmer grew nostalgic.

The part-time Sanibel resident started paddling and fishing the river about 15 years ago.

“There was bass fishing like I’d never seen before,” he said. “And the trees were so full of birds you wondered how they stood up.

“Now we’ve got to the point where there are no more bass — I haven’t caught a bass in three years — and if you see half a dozen birds, it’s unusual.”

The Sanibel River’s main problem is excessive nutrients, and the city of Sanibel is working on a series of long-term fixes.

Sanibel is unusual among barrier islands because it has interior freshwater wetlands, which cover 1,200 acres and drain into the Sanibel River.

But the Sanibel River is not really a river: It’s a meandering slough, or low area between ridges on the Gulf of Mexico and Pine Island Sound.

Originally, the slough was a series of channels that held water only after extended periods of rain.

Over the years, the slough was dredged for mosquito control and to provide fill for development; channels were connected to create the “river,” which now holds water all year — water levels are controlled by weirs at Tarpon Bay and Beach Road.

“This slough is rain-fed,” said naturalist Mark “Bird” Westall, who operates Canoe Adventures on Sanibel. “The water doesn’t melt out of the mountains. It doesn’t come out of a spring. If you get a lot of rain in the summer, it can get very wet. It can also almost dry up in winter.

“The slough can have bass in wet years. In drought years, the fresh water evaporates, and the bass population declines.”

Sanibel’s freshwater wetlands are the reason Sanibel has alligators when other barrier islands don’t.

Alligators, in turn, are good for the island’s wading birds because they keep raccoons from swimming to trees where birds have built nests.

“When birds see alligators, that’s a cue,” Westall said. “They figure, ‘OK, this is where we want to nest.’”

(Page 2 of 3)

Impaired waters

Under the federal Clean Water Act, each state must develop a list of impaired waters.

All water bodies have one or more designated uses, which include recreation, drinking and shellfish harvesting.

A water body is listed as impaired if it doesn’t meet its designated uses.

The Sanibel River’s designated use is freshwater fish and wildlife propagation, and the river is listed as impaired for nutrients, which can cause algal blooms, leading to low levels of dissolved oxygen.

“The river is supposed to provide habitat for fish and wildlife,” said James Evans, head of Sanibel’s Natural Resources Department. “We have fish and wildlife, but we don’t have a well balanced population of fish and wildlife.

“If we have algal blooms, that’s an indicator of imbalance. Until we get the imbalance fixed, the river’s impaired.”

Nutrients in many water bodies are from inorganic fertilizers, but a 2009 study showed that the source of much of the Sanibel River’s nutrients is organic nitrogen, said Eric Milbrandt, director of the Sanibel-Captiva Conservation Foundation Marine Laboratory and an investigator on the study.

“What happened is that people did fertilize, and a lot of that nitrogen was taken up by grass and ornamentals,” Milbrandt said. “So grass clippings ended up in the slough, and when those break down, they leave a lot of organic nitrogen behind.”

Seeking solutions

Sanibel has been working on and continues to work on ways to reduce nutrients in the river.

Beginning in 1998, the city started changing from septic to central sewer; today, 90 percent of the island is hooked up to the sewer system.

Another major step was the city’s fertilizer ordinance, adopted in 2007, which, among other things, prohibits the use of any fertilizer containing nitrogen and phosphorus during the rainy season.

The city has completed two water-quality projects and is planning a third to address the river’s nutrient problem.

■ Sanibel Gardens Preserve

Owned and managed by the city and Sanibel-Captiva Conservation Foundation, the 265-acre Sanibel Gardens Preserve straddles the slough just west of Tarpon Bay Road.

(Page 3 of 3)

A $450,000 restoration project, completed in 2005, included removal of exotic vegetation, planting native vegetation, filling mosquito ditches and restoring the natural oxbows that had been straightened when the slough was dredged.

These improvements increased wetland area and the time that water remains in the system, thus increasing the slough’s ability to filter out nutrients.

More wetland area also provides more foraging habitat for wading birds and water fowl.

■ Sea Oats Preserve

On a smaller scale is the 5-acre Sea Oats Preserve, which lies within the 450-acre State Botanical Site just west of Rabbit Road.

The preserve is on what had been the site of a package wastewater treatment plant, where sewage from the Sea Oats Subdivision was treated with chemicals in holding ponds.

Although the plant wasn’t on the river, nutrients from the ponds leached into it.

Sea Oats went on central sewer in 2003, and the city bought the plant for $1 in 2004.

Restoration took place between April and July 2009 and included filling the wastewater ponds, restoring historic contours of the land, removing exotic vegetation, planting wetland and upland vegetation and digging ponds as habitat for fish and invertebrates.

“The ponds will help move nutrients up the food chain,” Evans said. “Fish and invertebrates take in nutrients low in the food web; a wading bird eats the fish or invertebrate; the bird flies away and takes the nutrients with it.”

This project was financed with $21,800 from the South Florida Water Management District and $25,000 from the U.S. Fish and Wildlife Service.

■ Jordan Marsh Treatment Park

The 61-acre Jordan Marsh Water Quality Treatment Park will be a series of man-made marshes and filter ponds near the intersection of Periwinkle Way and Casa Ybel Road that will treat stormwater flowing south from Sanibel’s most developed residential and business corridor.

“This is a slough, and everything runs downhill into it,” Evans said. “If we don’t slow the water down, it will end up in the river untreated. The goal is to slow all that water down and clean it before it gets to the river.”

Funding is not yet available for the Jordan Marsh project, which which is expected to cost $500,000.

Lingering nutrients

At first glance, the Sanibel River looks healthy enough.

But, while it’s not clogged with trash and stinking with chemicals and other pollutants, it is impaired by excess nutrients.

Steps are under way to improve water quality, but despite central sewer, a fertilizer ordinance and restoration projects, nutrients will remain in the soil of the slough and affect the river for years.

“It could take decades for those to leach out,” Evans said. “It doesn’t happen overnight, but the citizens and wildlife will thank us when it’s all done.”

More In Things To Do

Top Stories

Local Deals

Flip, shop and save on specials from your favorite retailers on Marco Island

GET DEALS NOW

Marco beach cam

RESTAURANTS

Find local restaurants, read
and submit reviews

Celebrating the best of South Lee and North Naples

READ MORE

Reader Photos

Get the Hurricane Hub app

DealChicken.com

Sign up to save 50-90% off SWFL dining, shopping, spas, activities and more. Every day.