Excess Nutrients Cause Trouble In St. Johns River

Sep 10, 2014

In the first of six stories on issues facing the St. Johns River, WJCT’s Peter Haden reports on the essentials of nutrients.

Ben Williams owns the Fisherman's Dock seafood market in Mandarin. In the 25 years he has been selling fish in Jacksonville, he's seen people's attitude toward the St. Johns River shift.

"Thirty years ago, people would specifically ask, 'Is that river shrimp?' And they were asking that question because that’s what they wanted. Today, they ask that question because they’re scared that it is a shrimp out of the river," Williams said. "They hear all the negative publicity. They saw the 'Green Monster.'"

The Green Monster, a mat of blue-green algae that covered the St. Johns River for a hundred miles, first became a major problem in 2005. Three things conspired to create the slime: warm weather, slow-moving water and nutrient overload.

"An overabundance of nitrogen and phosphorus in particular," said Derek Busby, Initiative Leader at the St. Johns River Water Management District.

The District collaborates with public agencies and local governments from Orlando to Jacksonville to figure out how to reduce the amount of those nutrients in the river.

Over the past 20 years, state and local governments have invested millions of dollars in upgrading sewage treatment plants, reducing industrial discharges and reclaiming wastewater. These are called "point" sources, ones that can be easy to identify and fix.

But it’s the "non-point" sources, like fertilizers and storm runoff, that Busby said are the most difficult to tackle.

"A lot of it happens on our own lawns. We all have to take responsibility and understand that we are all part of this," he said.

Busby and the District have been sharing costs with institutions for two decades to come up with better methods of handling wastewater and storm runoff. Among the first of these green eco-champions to step up was Naval Air Station Jacksonville.

The base sits in a bend of the St. Johns River south of downtown, and employs 23,000 people. By the end of 2015, the base will be a zero-discharge facility - it won’t put any wastewater in the St. Johns. Instead, the reclaimed water will be used for irrigation.

NAS Jax is hoping a new breed of parking lot will help to reduce non-point pollution, said Stormwater Manager John Young.

New parking lots at the base look like a latticework of concrete strips with grass growing in the squares in between. This and other design techniques allow rainwater to slow down and be soaked up by native plants.

"If we were in a normal parking lot - the giant slab of asphalt - we would be sending almost all of the water into the nearest river or lake or ocean," said Young.

The new parking lots will not only stop that water from getting into the St. Johns River, but also everything it is taking with it.

You can follow Peter Haden on Twitter @HadenMedia.