South Miami-Dade farmers who prefer to use natural fertilizer instead of synthetic will soon have more choices.
Homestead and South Dade Soil and Water Conservation District, a nonprofit conservation organization, have partnered to open a facility that will turn all of the city’s biosolids, or sewage, into fertilizer marketed as Homestead Organix.
Three times a week, 10 cubic yards of material is delivered from the nearby Homestead Water Treatment Plant.
The material is put inside a rotating composter for four days. The rotating drum circulates oxygen through the biosolids, allowing bacteria to generate enough heat that pathogens, or disease-causing bacteria, are killed.
The oxygen “makes the right bacteria grow,” said Bill Townshend, projects manager at the SDSWCD, which designed the city’s facility. “The composter, it just turns real slow and generates enough heat to kill the bad guys.”
Finally, the product is spread in a greenhouse to cool.
The concept of composting waste is nothing new. Before synthetic fertilizer was invented, farmers used animal manure to replenish their soil.
“What we are doing is not a big secret,” Townshend said. “The rest of the world is doing similar things.”
Currently, Miami-Dade and Palm Beach counties have programs that compost human waste into fertilizer.
But Homestead’s system is an improvement of the Black Point facility, designed by the SDSWCD as well as the county. Because Homestead’s greenhouse is built with a retractable roof that closes when it rains, the facility can operate year round.
The county’s system has no roof – and is susceptible to rain.
“It’s a waste,” said Morgan Levy, administrator at the SDSWCD, speaking of the county’s system. “The problem there is, we have six months of rainy season. So they are not able to dry it enough to put it in the composter. In fact, this season we’ve had so much rain, we can’t dry it.”
Palm Beach County’s Biosolids Pelletization Facility uses methane gas generated by a landfill to dry its sewage sludge and then sell it as a fertilizer.
The SDSWCD said Homestead Organix will fill a void in the market for composted sewage sludge fertilizer.
“Farmers are crying for it,” said Levy. “You see how much benefit that could have to local farmers who are fighting foreign competition to stay in business.”
Homestead Organix will be sold for $5 per 40-pound bag. That is cheaper than some all-purpose fertilizer sold for about $16.50 per 40-pound bag at chain stores.
Tropical fruit tree farmers like Daniel Lyons are excited about having more options.
“I’d say it is definitely needed,” said Lyons, owner of a 120-acre Redland farm where he grows mango trees as well as bananas.
For at least the last decade, he has been using the composted sewage sludge from Miami-Dade and Palm Beach counties.
“I think more growers will go to it (Homestead Organix) because it is less expensive than synthetic. It’s always a great effort to try to make a profit,” he added.
But not all South Miami-Dade farmers are sold on the idea of Homestead Organix – or on the idea of using fertilizer generated from composted municipal sewage sludge.
“I am not excited about that product. I have to avoid it like it is leprosy,’’ said John Alger, president of Alger Farms, a vegetable farm in Homestead.
Since Alger sells his vegetables to retail chain stores, he has to pass a third-party audit that questions whether his fertilizer includes human waste.
“If it has any fecal matter, it ain’t happening. It’s a great idea to fertilize your lawn, but don’t touch food,” he said.
Townshend said that even though his product is safe to use on vegetables, he is not marketing the fertilizer to that industry.
“The tropical fruit industry and the citrus industry absorb more material than I can make,” he said.
The SDSWCD is a government agency. That means that all fertilizer produced at its facilities must meet state Department of Agriculture safety regulations as well as all federal, Miami-Dade County and Environmental Protection Agency regulations, said Townshend.
Laws dictates that dried sewage sludge must be composted for at least three days at 131 degrees Fahrenheit, said Townshend. But the SDSWCD composts its product for four days at 160 degrees, he said.
Alger, however, said the conditions set by his third-party audits are more stringent than those dictated by national, state and county laws.
“It doesn’t matter what the federal government says. It matters what the retailers say. Their standards are much higher,” he said.
Homestead staff said the facility will pay for itself within two and a half years since the city will save on the annual $200,000 dumping fee to the county. In addition, the city will receive 10 percent of the profits from the sale of Homestead Organix.
The SDSWCD, which maintains the facility at no cost to the city, will receive the rest of the profits.
Lyons, the tropical fruit tree farmer in Redland who plans to purchase Homestead Organix, sells his mangoes, papayas and bananas mainly to wholesalers and has his products tested through a U.S. Department of Agriculture audit.
“Municipal sludge is now AA certified. It’s not like putting raw cow manure in the field,” he said. “The only stumbling block is that the vegetable guys are resistant to using it because their customers have said they don’t want them to use it. I guess they are fearful of food-born illnesses, which really isn’t the risk with this stuff but it has this reputation I guess.’’