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I I - ZD Seagrass provides a protective enviroriment in which young marine life can develop, but with the Lagoon's critically high levels` of nutrients, the deterioration of seagrass beds created an undeni- able concern: Compelled by state law to act, the County Commis-. , "Sion passed the mandate; which is airried at regulating the TMDL. What happened? r' DILEMMA By Keith MacDonald ast month on July 3rd, the Indian River County Commission passed the State Model Fertilizer Ordinance, which is intended to reduce nitrogen, potas- sium and phosphorous levels in the Lagoon. Currently, the Indian River Lagoon has been designated as an impaired body ofwater by the EPA due to its high levels of pollution and the ensuing loss of seagrass and marine life. The EPA and Florida DEP determine the amount of nutrients allowed, or TMDL - the Total Maximum Daily Loads. Cover photo: Oysters are used to filter the lagoon's nutrient -rich water. Photo by si.by Hanson 2 Vero's Voice Issue 31 During the summer ofzo11, a "super bloom" of oxygen -con- 1 suming algae exploded into the northern lagoon. The algae choked off the lagoon's natural seagrass, killing 45% of it over the next eight months. This kicked off a period of rapid decline in lagoon health that still exists today. To date, two-thirds of the seagrass between Vero Beach arid the northern end of the Indian' l River Lagoon has disappeared The controls that were implemented in the 199os seemed to be ` creating a positive effect on the flourishing seagrass, bit according to St. Johns River Water Management models, the drier weather we experienced between 1998 through 2010 was more responsible for keeping approximately 80,000 kilograms of chemicals out of the lagoon each year. This surpassed any controls that could be put into action by regulation. (By comparison, the county removes approximately 6o,oao kilograms through its scrubbing, skimming and purifying efforts.) But, as is the case in many experiments gone awry, the blame for the depleted seagrass problem has been placed squarely on the shoulders of... the Indian River County Commission. What's being done was already being done... 1 met with County Commissioner Wesley Davis at the North Relief Canal project at Spoonbill Marsh and received a first-hand tour of an impressive, eco -friendly filtration system of pods, mats and runnels. "What we have created is a first-class saltwater estuary and marsh," said Davis. "The brine that used to be directly discharged into the lagoon is now being processed through 6o acres of for- merly low-grade marsh that was laden with invasive plants. These plants were strangling the natural vegetation." An impressive pumping station sits at the mouth of the large canal which channels lagoon water into the estuarywhere it passes through floating mats of vegetation anchored around brine -pump- ing sprinkler systems. "Under those mats, the roots of these mangrove plants extend down and consume the nutrients in the water being passed through," says Davis. "We process all of our brine right here using reverse osmosis. We pump the brine up and process it through an eco -friendly, natural process." But we're not done yet