Pollution puts coral reefs off Florida's coast in peril

Agricultural run-off and sewage encourage algae

Forty-two madrepore corals were dead, counted during an hour-long dive 50 feet down in the Atlantic waters off Boynton Beach, Fla. Others were half-dead, with stark white patches on otherwise healthy animals.

Coral reefs everywhere are in peril. Many reefs are dead, some are dying, and most are subjected to pollution. How that extermination process is taking place along the coast of America's only continental reef structure, is a story of overpopulation, greed, and negligence.

Scientific base research of the reefs will take years, experts say. But anecdotal evidence reported by concerned divers is urgently warning of the demise of America's last frontier, Florida's Atlantic coral reefs.

"The outflows were terrible all summer long," Capt. Leo Sand says. Owner of the Deeper Dive Fleet, Captain Sand runs scuba charters and trips out of Boynton Beach. His dive boats are on the ocean every day. But recently his customers have reported visibility problems as the South Florida Water Management District opened the gates of its canals.

This allowed fresh water containing agricultural runoff and drainage, as well as sewage, to flow into Lake Worth and the Intracoastal Waterway. At tide change, the flow dumps directly into the ocean.

Sand says the release of water from the canals of Florida's flood-control system is killing the coral. "We see it that same day as dirty, silty, particulate matter that settles on the reefs," he says.

Corals are marine animals, not plants. Free swimming at the beginning of their lives, they eventually settle on some substrate, attach themselves, and begin a colony. Reefs not only prevent beach erosion but provide homes, in their nooks and crannies, for many marine creatures.

The reefs that corals build exist in a complex cycle of life that requires clear, warm water. Tiny plants called zooanthellae live inside corals and produce oxygen and other nutrients while using the coral's waste products.

Sewage, wastewater from storm drains, and agricultural runoff carried by canal water all contain high levels of nitrogen and phosphorus. These elements stimulate excessive growth of algae.

The South Florida Water Management District recognizes the problem. "The alternative is flooding," their managers say. "The system was designed to push water away, not to store it."

None of this bodes well for Florida's reefs. In 2001, Brian Lapointe, a research scientist at the Harbor Branch Research Institution at Fort Pierce, studied the effects of nitrogen pollution on the reefs from Deerfield Beach to Jupiter. Nitrogen levels registered highest off Boca Raton, where sewage is piped into the ocean. Dr. Lapointe's studies revealed that algae now extend over large ocean areas from the Lake Worth Inlet to the Jupiter Inlet.

"Septic tanks are leaking, and sewage being pumped underground is feeding algal growth," Lapointe says. He adds that seepage from these wells is also finding its way into the ocean.

Proposed long-term improvements would add billions of dollars in storage to prevent fresh water containing agricultural runoffs from being pumped into the ocean. In the near term, freshwater conservation and use of environmentally friendly detergents may help. Restricting population incursion into sensitive areas is another good idea, local experts say.