Jacksonville is launching a study to see just how effective a bacteria-based technology is at removing nitrogen from water bodies, a leading driver of harmful algal blooms.
Over the next year nine ponds throughout the city will be periodically sprayed with Microbe-Lift, a blend of bacteria manufactured by Ecological Laboratories to reduce nitrogen in ponds, landscaping and irrigation. Meanwhile staff from the City’s Environmental Quality Division (EQD) will collect samples every month through December 2020 to measure the levels of total nitrogen.
“Based on the pilot study we did at three ponds in 2015, we are hopeful for a 60 percent reduction in total nitrogen, which is more than double the amount a normal stormwater pond would achieve,” said Melissa Long, chief of EQD.
The study is being funded with more than $300,000 in donations, grants and in-kind contributions from the Florida Department of Transportation, the St. Johns River Water Management District, the Jacksonville Environmental Protection Board and the Florida Department of Environmental Protection.
“Jacksonville’s tributaries and the river, which are currently impaired for nitrogen and E. Coli bacteria, need pioneering solutions to reduce pollution, preserve our environment and enhance quality of life,” said FDOT Project Management Engineer Alan Obaigbena.
The City is obligated to reduce total nitrogen under the St. Johns Basin Management Action Plan. Due to Jacksonville’s size and population, it has to reduce more nitrogen than any other municipality in Florida. This study is just one of several approaches the City is taking to meet its goal.
“Nitrogen in our waterways leads to algae blooms in high enough concentrations, which of course has effects on fish, wildlife, swimming, recreational activities, things like that,” said Dale Jenkins, Bureau of Project Management Chief with the St. Johns River Water Management District. “We know if we can reduce the total nitrogen and total phosphorus that gets into our waterways, they'll be cleaner and the environment will, as a result, be better off.”
Sources of nitrogen in Florida’s water include septic systems, fertilizer, livestock waste, polluted rain and wastewater treatment facilities. Long said there are some commercial sources as well.
“Everybody who discharges in this area, from the mouth of the river down to Welaka, are stakeholders in the lower St. John's basin management action plans,” she explained. “They're all required to make reductions, including us.”
Douglas Dent, Technical Director at Ecological Laboratories, said the chemicals frequently used to reduce Nitrogen levels in retention ponds work, if aesthetics are your main concern. “You kill it off. It looks good for people, but it biologically breaks down and releases all the nutrients back and downstream they go,” he said.
Microbe-Lift, on the other hand, uses natural processes to remove organics, control pathogens and get rid of nutrients, primarily nitrogen compounds. The bacteria in Microbe-Lift convert nitrate (a form of nitrogen that algae loves to feed on) into nitrogen gas, which is then released into the atmosphere.
And according to the City and Ecological Laboratories, there are no toxicity concerns with Microbe-Lift at all. In fact, it’s frequently used to maintain aquariums and coy ponds and it’s used in aquaculture.
“These are products that are used in homes all the time and it's been used in the sanctuary out at the Jacksonville Beach for 12 years in their pond system,” said Long. “So we don't anticipate any issues with it.”
But to avoid any interference with the tests, residents are being asked to stay out of the test ponds:
- FDOT pond at the intersection of Alamo Street and Huntsford Road
- City pond at the intersection of Kona Avenue and Century Street
- FDOT pond at the southwest intersection of I-295 and Lee Road
- City pond at the intersection of Ft. Caroline Road and Spanish Oaks Drive.
- City pond just north of Ansley at Harts Road apartment complex at 11011 Harts Road
- City pond just west of 7914 Pritchard Road
- FDOT pond at 10420 General Avenue
- City pond at 2581 Commonwealth Avenue (COJ Fleet Maintenance)
- FDOT pond at the southwest intersection of Forest Street and Myrtle Avenue
Jenkins said when Jacksonville first submitted the application to conduct these tests back in September 2018, SJRWMD staff scored it very high in their evaluation.
“We think there's good promise,” he said. “Their pilot programs have demonstrated that this technology works.”
And if these tests confirm that suspicion, the intent is to apply Microbe-Lift on a larger scale.
Dent said it’s already being used across the globe to improve the water quality of rivers and streams.
“In China we treat flowing rivers, major rivers, and in Indonesia we treat major flowing rivers. So the capability’s there, you just scale it up,” he said. “We’ve been doing it for years. We can take what’s called a class five toxic river and within anywhere between two to four weeks have that water quality up to agriculture standard.”