Water bodies, watersheds and storm water

Lower St. Johns River Basin

The St. Johns River is one of the laziest rivers in the world. The total drop of the river from its source in Indian River County to its mouth at Mayport is less than 30 feet — or about one inch per mile.

In the river’s lower basin (that portion of the river from Lake George flowing north to the river’s mouth at Mayport), a wide variety of everyday activities unintentionally add nitrogen and phosphorus, or nutrients, to surface waters. In fact, every year, more than 32 million pounds of nutrient pollution enter the St. Johns River — that’s the equivalent of more than 500 full dump trucks.

Treated wastewater is the largest contributor of nutrient pollution in the lower St. Johns River. In everyday terms, wastewater is partially treated sewage, which is transported by underground pipes to a wastewater utility’s plant for treatment and disinfection. Then, oftentimes, the treated wastewater is pumped to the St. Johns River for disposal.

Other significant nutrient pollution sources include farms in the agricultural areas of Flagler, Putnam and St. Johns counties. Agricultural runoff from farming areas take animal wastes, fertilizers and pesticides into the waterway through canals, ditches and streams that lead to the river.

Storm water from urban and suburban areas also pollutes the river. Runoff from metropolitan and developed areas sends lawn fertilizers, sediments, pesticides, roadway grease and trash into the river and its tributaries. Storm water contributes 80 to 95 percent of the heavy metals — copper, lead and cadmium — that enter Florida waters.

The upstream watersheds of the upper and middle St. Johns River also contribute significant amounts of nitrogen and phosphorus to the lower basin. Lake George is especially vulnerable to upstream pollution sources because the river water slows as it drains into the large, shallow lake, increasing the retention time of the water. The lake also contains nitrogen-fixing bacteria, which take nitrogen from the atmosphere and introduce it to the lake. This process is estimated to add more than 760 metric tons of nitrogen per year. In turn, Lake George affects water quality in the downstream portions of the lower St. Johns River, which increases the production of algae in the lower basin.

Because of these everyday impacts, pollutant loads currently exceed the amount that the lower St. Johns River can receive and still meet state and federal water quality standards.

What’s more, the nutrient-rich discharges into the river have fed harmful algal blooms, which block sunlight from reaching aquatic plants, produce toxins, deplete dissolved oxygen and endanger fish and other wildlife. Loss of underwater vegetation also deprives manatees and other wildlife of their primary food source, and fish of their most important habitat.

Progress is being made

From the air, the St. Johns River appears to
snake among the trees along its shoreline.

Since 1987, when Florida’s Surface Water Improvement and Management (SWIM) Act was passed, Florida has heightened its efforts to improve regionally impaired water bodies, including the lower St. Johns River. The SWIM Act directed the St. Johns River Water Management District to conduct the necessary research to gain an understanding of what is needed to restore and properly manage the river and to develop a plan for that work.

District scientists and engineers have conducted research about the river and its ecology and have moved forward on numerous projects to improve the river’s health.

Currently, the most comprehensive study of the lower and middle St. Johns River basins is under way. The District is committed to ensuring protective standards are established for the area’s water resources as river water withdrawal proposals are discussed. As part of this commitment, the District is undertaking an evaluation of potential environmental effects resulting from proposed river water withdrawals on the biological and water resources of the St. Johns River Basin. This information will provide needed guidance on permit applications for river water withdrawal decisions and advance the overall scientific knowledge of the river that is used by the District and its partners to address river issues.

The District also has been a leader in the development of two notable partnership initiatives to restore the river to health — the 1998–2003 River Agenda and the 2006 River Accord partnerships.

The River Agenda and River Accord

In December 1997, more than 400 local, state and federal government officials and citizen advocates met to focus attention on the critical need to protect and preserve the St. Johns River. This resulted in a five-year plan — the River Agenda — and the creation of the Lower Basin Executive Committee to ensure that the goals outlined at the first River Summit were met.

River Agenda goals were to:

• Reduce point source (wastewater and industrial discharges) pollution
• Reduce nonpoint source (or stormwater) pollution
• Reduce bacteria in the tributaries
• Restore degraded aquatic habitat
• Increase water quality compliance and enforcement
• Increase public awareness of river issues

In the marine (salty) section of the river, wastewater and industrial discharges account for 22 percent of nitrogen (the key pollutant) entering the river. In the freshwater portion of the river, both nitrogen and phosphorous are of concern. In the freshwater portions, point sources account for 6 percent of nitrogen and 22 percent of phosphorous loading.

The Jacksonville skyline along the St. Johns River.

While progress has been made in reducing some pollutants, an optimization study completed in 2008 determined that using advanced nutrient removal treatment technologies for improving wastewater treatment is the most cost-effective solution to reducing the amount of nutrients going into the river.

Beyond improved treatment, redirecting the disposal of wastewater and using the reclaimed water for nonpotable (nondrinking) uses, such as irrigation, will improve the river’s ecological health, protect and conserve Florida’s precious water supply and assist in providing for sustainable growth in northeast Florida.

Currently, few areas in the lower basin have the infrastructure in place to support use of reclaimed water. Through cooperative efforts, more than 20 reclaimed water projects are expected to begin or be completed by 2014. These projects are intended to remove nitrogen discharges from the river — helping to improve water quality. At the same time, they will make reclaimed water available for irrigation, which will conserve existing drinking water supplies. When these reclaimed water projects are implemented, it is estimated that they will remove from the river approximately 1.6 million pounds of nitrogen per year and 32 million gallons of wastewater per day — or 10 billion gallons per year by the year 2025.

The reclaimed water projects that are now being implemented are part of the District’s participation in the River Accord, a $700 million partnership with the city of Jacksonville, JEA, the Florida Department of Environmental Protection and other local government partners. The River Accord was signed July 27, 2006. In it, the District agreed to spend up to $150 million on reuse cost-share projects over a 10-year period.

In addition to the District’s wastewater reduction and reuse initiative, River Accord partners will identify failing septic systems and develop a plan to tie those homes into central sewer systems, upgrade wastewater treatment plants, and improve the treatment of stormwater runoff. These combined efforts will bring the nutrient loading well below state and federal standards and provide more than 50 million gallons of reuse water over 10 years.

Updated on 5-6-2011