nitrates

The Contamination Complication

Mark and Annette Long have lived in Florida for most of their lives and lately they’ve noticed something wrong with the local waterways.

“The water is covered in algae and it doesn’t have a whole lot of flow,” said Mark. “The spring basins aren’t what they used to be.”

Mark is a Florida native and Annette  moved to the state about 30 years ago.  They said they began noticing problems with the water in Florida about 10 years ago.

Alarmed by this observation, the couple who live in Chiefland,  became activists for water issues in their area. They started Save Our Suwannee, which engages in a number of activities from educating the public to lobbying local governments. Of major concern to them is nitrate pollution.

Nitrates (NO−3), or nitric acids, are chemicals commonly found in fertilizers and waste.

Paul Chadik, a University of Florida professor of environmental engineering sciences, said nitrates are a nutrient for the development of algae growth, causing harmful algal blooms. This process is known as cultural eutrophication.

Chadik said that when the algal cells start decaying, the bacteria that catalyze the process absorb large amounts of oxygen from the water.

“Other aquatic life that needs the oxygen can’t get it,” he said. The aquatic ecosystem would be damaged, he said.

A 2008 Florida Department of Environmental Protection study reported that nitrate pollution in both surface and groundwater has increased by a factor of two or three over the last 20 years.

According to the study, about 30 years ago, nitrate levels in Florida’s water were about 0.2 mg/L. Now, the average is about 1.0 mg/L.

The Longs both said they were very concerned over the amount of nitrates finding its way into the water.

Severe environmental degradation can occur at 0.4 mg/L, said Annette, who serves as president of Save Our Suwannee. That’s the general scientific consensus among the experts she has spoken with.

“It causes algae to bloom once it’s exposed to the sun,” she said. The algae overgrowth then “smothers out the healthy aquatic vegetation.”

The maximum contaminant level (MCL), a standard set by the Environmental Protection Agency, allows 10.0 mg/L of nitrates.

Annette also said nitrates pose a threat to the humans drinking the water.

“There are even studies that indicate a level of 1.5 (mg/L) causes bladder cancer.”

Agriculture is one of the major source of the pollutants, the Longs said. Fertilizers commonly used in agriculture contain nitrates, herbicides and phosphorus. He said the rain washes the chemicals into both ground and surface water.

Terry Hansen, an environmental consultant for the environmental protection department, agrees that the Suwannee and Santa Fe rivers are in poor condition.

“The state has determined both the Suwannee and the Santa Fe are impaired,” he said.
An “impaired” means the water body has been evaluated and found it is not meeting intended use.

The state ranks bodies of water based on a scale of one to five. A one means the water is drinkable, and a five indicates the water is for navigation and industrial use only.

The Suwannee and Santa Fe rivers are both class three water bodies, meaning they are for swimming, fishing and recreation. Impaired water bodies exceed the pollution allowed for a class three.

To address this issue, the department has implemented a Best Management Action Plan (BMAP). A BMAP is a collection of methods used to lower pollution.

For instance, the BMAP for the Santa Fe River prescribes a public education campaign about the impact of stormwater and new guidelines for controlling pollution from construction sites, as well as other sources.

Hansen said the complex nature of Florida’s water systems is one reason why pollution is such a major problem. The underground aquifer connects to several bodies of water, meaning nitrates and other nutrients can have a wide reach.

“There is no single place you can implement a system of control,”Hansen said.

A 2010 study, conducted by MACTEC, a private consulting firm, funded by the  Florida Department of Environmental Protection, analyzed sources of nitrate pollution in the Santa Fe River and its springs.

According to the study, water bodies near agriculture contained about 4.0-5.5 mg/L of nitric acids on average, significantly higher than the amount Annette said was dangerous. Water near undeveloped areas contained about 0.1 mg/L.

Another part of the problem, Annette said, is Florida’s lack of enforcing effective environmental policy.

“The state is bowing to industry,” she said, and “dragging its feet” in setting standards for limiting pollution.

The federal Clean Water Act, passed in 1972, made it unlawful to discharge pollutants into the water from a point source (pipes or man-made ditches) without a permit. Mark said far too many of these permits are being issued to industrial businesses such as paper mills.

Cris Costello, a regional organizer for the Florida Chapter of the environmental advocacy group, the Sierra Club, expressed a similar opinion.

“The problem is that FDEP considers polluters their customers,” she said. “They cater to those customers to an incredible extent to such an incredible extent that the environment suffers.”

Florida needs to adopt numeric limits to water pollution.Rather than being proactive, state currently doesn’t take action unless the water is already green and slimy, she said.

The Florida Department of Environmental Protection finalized a plan in January 2012 to implement a numeric limit, which is awaiting approval by the U.S. Environmental Protection Agency, Costello said.

The Sierra Club advocates a cheap and easy way to limit nitrate pollution is with local laws regulating fertilizer use, he said.

Manatee County, Fla., is the latest county to adopt regulations on nitrate-based fertilizers. The ordinance prohibits the use of fertilizers containing nitrogen or phosphorus from June 1 through Sept. 30, due to heavy rainfall during these months. In addition, it limits where the fertilizers can be used.

Annette said rules like these should be implemented across the entire state.

The couple remains optimistic that Florida’s water situation will improve.

On the subject of water, Annette said, “It’s the only reason people come to my town.  I hope things will turn around.”