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Facts & Fiction: Numeric nutrient criteria and water quality

By Staff | Jul 27, 2011

Residents and businesses in Southwest Florida know the truth about nutrient pollution first hand. We live with the truth in our backyards. Devastating and ongoing algae blooms impact our livelihoods, our use and enjoyment of area waters, our properties, businesses and the natural resources that are the engine of our local economy.

The serious and persistent algae blooms that continue to affect Southwest Florida — and other areas of the state — are the direct result of too much nutrient enrichment of our region’s waters. Simply put, nitrogen and phosphorus levels are way beyond what the natural system can absorb. Southwest Florida is not alone, the problems of nutrient enrichment reach all corners of our state and nation, impacting some of our most unique and precious resources.

This is why the current effort to establish standards for nutrients is so important. Decades ago, regulations were developed to address many aspects of water quality. Unfortunately in Florida, the regulation of nutrients has been ineffectual since no numeric standard of harm was established to measure nutrient enrichment. Instead, Florida adopted a subjective, narrative standard of “healthy well-balanced systems” which has no scientific method of measurement. My definition of “healthy well-balanced” may not be the same as someone who is contributing significant nutrient pollution.

In fact, under the current definition we have seen the degradation of local waters that in the 1980s were such unique and special resources they were awarded the status of Outstanding Florida Waters (OFW). Today, these same waters are impaired by nutrient pollution that affects water quality and the amount and quality of the habitats upon which our unique aquatic life forms depend.

After years of deteriorating water quality and ten years of inaction by our State water quality agency, the Federal Environmental Protection Agency (EPA) has developed a numeric standard for nutrients in Florida called the Numeric Nutrient Criteria. This first set of standards for lakes and streams has become a tug of war between the State Department of Environmental Protection (DEP) and Federal EPA and is being hotly debated.

Last week, a group of industry groups submitted an opinion to The Florida Independent news misrepresenting the scientific facts, including the suggestion that Caloosahatchee algae blooms are not due to nutrient pollution but are the result of this year’s drought! The industry opinion can be read on our website:

In the interest of clarifying the facts associated with our water quality conditions and the need for numeric nutrient criteria we provide a few facts to address statements made to set the record straight.

• Industry statement: “The [Caloosahatchee] algae bloom was a result of the lack of freshwater flow to the Caloosahatchee River due to the historic drought in South Florida.”

• Fact: Nutrients are needed for algae to grow. Lack of water flow concentrated the nutrient soup compounding the problem, but the bloom would not have occurred had there not been noxious levels of nutrients in the water to begin with.

• Industry statement: Unsurprisingly, water quality is improving.

• Fact: Improving water quality from a toxic condition to a less dangerous condition must not be confused with clean, healthy, fishable, swimmable water quality — the standard that numeric nutrient criteria are designed to establish. Rain washing algae downstream merely moves the nutrients downstream to our coastal waters where they will continue to pollute, preventing fishable, swimmable waters.

• Industry statement: Mr. Guest’s letter failed to mention that the Caloosahatchee River already has an EPA-approved numeric nutrient pollution limit.

• Fact: The Caloosahatchee has two basic components: the downstream tidal Caloosahatchee and the upstream (east of Franklin Lock) freshwater Caloosahatchee.

1. Only the tidal Caloosahatchee has an established TMDL (Total Maximum Daily Load; that establishes a limit for nitrogen pollution). The majority of the river, including all the freshwater portion of the river and upstream tributaries that flow into the tidal waters are not covered by the TMDL.

2. The tidal TMDL only establishes a limit for nitrogen, not phosphorus. Unfortunately the toxic bluegreen algae that has plagued the Caloosahatchee for the past eight weeks blooms on phosphorus and can obtain the nitrogen it needs out of the air — which contains 78 percent nitrogen. There is no TMDL for phosphorus in the Caloosahatchee so even if the nitrogen TMDL limits were magically met tomorrow the algae could continue to bloom.

• Industry statement: The state law requires a 22.8 percent reduction in nitrogen loads to Tidal Caloosahatchee estuary downstream of the S-79 Franklin Lock and sets a numeric nutrient limit of 9,086,094 pounds of Total Nitrogen per year.

• Fact:. The lack of an upstream TMDL means that nitrogen sources upstream will continue to undermine best efforts in downstream tidal waters.

The devil is always in the details… and in the scientific facts. We need numeric nutrient criteria and we need them now. We must not allow inertia and fear to prevent science from moving us to clean, healthy, fishable, swimmable waters for ourselves and the generations to come.