Wednesday, July 14, 2010

Floating Gardens Help, But the St. Johns River Needs More

Toxic algae blooms have become an all-too-familiar sight (and smell) along the St. Johns River. Experts agree that these blooms are in large part due to high nitrogen and phosphorous levels entering the river through fertilizer runoff and leaking septic tanks. The City of Jacksonville has taken a few measures in an attempt to alleviate this growing problem, namely building retention ponds and running an advertising campaign to warn citizens of the damage over-fertilization can cause. The Times-Union recently ran a story about a new weapon the city is employing to reduce pollution levels in the river. Much like using plants to clean up contaminated soil (see post below), the city’s latest tactic uses plants to remove pollutants from contaminated water. But is this a long-term solution?

Floating on buoyant pallets, specific “nutrient-eating” plants bob on the surface while their roots do the dirty work below. These plants, Redtop, Soft Rush, Canna, Pickerel, Bur-Marigold, and Arrowhead, have proven to be highly effective at absorbing nitrates and phosphates from water. Once the plants have soaked up as much as they can handle, they are replaced. Although they do not remove 100 percent of the contaminants in the water, floating gardens represent a highly cost-effective way to combat pollution in the river.

However, floating gardens cannot stem the relentless tide of contaminants that pour into the river on a daily basis. It is merely reactive. In the long run, the city needs a stiffer regulatory framework of prevention. No matter how many floating gardens the city installs, over-fertilized lawns and leaking septic tanks will continue to undermine any remedial measures. This is not to say that the right to care for one’s lawn should be taken out of a homeowner’s hands. But, unless the city does something to incentivize landowners to use less harmful fertilizers or have their septic tanks inspected, algae blooms, dead fish, and putrid smells will become the river’s trademark characteristics. Only when Jacksonville dramatically reduces the amount of pollution entering the river can it work toward cleaning out the filth that is already there.

-Legal Extern, Kyle Johnson