(Editor’s note: This column mentions gross stuff that we all do because we are biological entities. Be an adult about it, please — this is important.)
We all know that Florida has a nutrient pollution problem. Multiple red tide and cyanobacteria blooms have made that fact glaringly obvious. Everyone from the governor on down knows it’s an issue that needs to be solved, or we’ll never have the clean, healthy waters we all want, demand and deserve.
Of course, the biggest stumbling block in finding a real solution to the problem is that so much of those nutrients come from us. Every time you flush a toilet, you’re contributing to the problem.
Sewers are the answer usually put forward. Looking at sewer versus septic tank, we see some positives. Septic tanks, by design, leach nutrient-laden water into the aquifer. Not good — especially in sandy Florida, where the water table is high and liquids quickly percolate down to it.
At least with sewers, which collect wastewater and transport it to a treatment plant, we have the option to remove some of the nutrients. (Some municipalities do; some don’t.) But sewers are prone to leaks. In “unforeseeable emergencies,” which seem to happen every other time it rains, hundreds and sometimes many thousands of gallons of raw sewage are often spilled (dumped) into local waterways.
Both options are better than going in a bucket and dumping it in the river, but you’d think that we might have come up with a real solution to what to do with our waste. After all, we’re all in the bathroom every day.
Each of us produces, on average, 1.5 quarts of urine every single day. Evaporate the water and you’ll have about 60 grams of solids left. On our typical American high-protein diets, that 60 grams contains about 10 to 15 grams of nitrogen, plus a gram of phosphorus and one or two grams of potassium — all three of the macronutrients needed for plant growth.
Of course, we poop too (about 150 grams a day, on average). About 75 percent of that is water, which leaves about 40 grams of solids. About 5 to 10 percent of that is nitrogen, so 2 to 4 grams daily. We also excrete about 0.4 to 0.8 grams each of phosphorus and potassium.
So, let’s tally that up. We’re at 12 to 19 grams of nitrogen, 1.4 to 1.8 grams of phosphorus and 1.4 to 2.8 grams of potassium for each and every one of us, every day. In a year, that’s 4.4 to 6.9 kilograms of nitrogen, 0.5 to 0.7 kg of phosphorus and 0.5 to 1 kg of potassium — per person.
There are about 1.5 million of us living in the Charlotte Harbor watershed. So that’s 6.6 to 10.4 million kg of nitrogen, 750,000 to 1 million kg of phosphorus, and 750,000 to 1.5 million kg of potassium each year, just from the local population.
That’s enough nitrogen to fertilize about 120 square miles of corn fields — and corn is a notoriously fertilizer-hungry crop. Florida is home to 22 million people. We could fertilize 1,760 square miles — about the size of Charlotte, DeSoto and Sarasota counties put together — of corn.
But we don’t fertilize corn with it, and most of it isn’t removed through water treatment. Instead, we dump it into groundwater (through septic tanks) or surface water (through sewage systems). We spike our waters with fertilizer, and then we wonder why we have problems with algae.
In July of last year, National Geographic had a piece about sanitation in poor nations that don’t have the kind of money required to develop and maintain sewer systems (“New Places to Go,” pages 30-31). Look at how much people in Port Charlotte and Cape Coral have complained about the cost of getting connected to sewers. How can people who are living on a few dollars a day supposed to bear that expense?
Instead, other solutions are coming to the forefront. And while these answers are meant for third-world countries, they have the potential to revolutionize how we deal with our own waste right here in America.
The goal here is simple: Build a self-contained toilet and waste treatment plant that does not require a connection to running water, yet still is simple to use and doesn’t require lots of expensive maintenance. It can’t produce unseemly smells that most users won’t find acceptable. And whatever comes out (because something has to come out) must be hygienic and easy to handle.
The Bill & Melinda Gates Foundation has been working with inventors since 2011 through the Reinvent the Toilet Challenge (https://gates.ly/38XdHbm), a contest which has the aim of producing “a truly aspirational next-generation product that everyone will want to use — in developed as well as developing nations.”
Some of the contest entries are hopelessly complex, but others are getting close to real-world simplicity. The best ones recycle the flush water and turn solid waste into either ashes (using internal incinerators) or dry cakes. The cakes or ashes are where the nutrients end up, and can be used to fertilize crops.
In poor countries, the development of an off-the-grid toilet is life or death. According to the foundation, unsafe sanitary practices kill half a million children under the age of 5 each year. They also cost more than $200 billion in health care costs and decreased income and productivity.
The next generation of sanitation will also be a revolution for the rest of us. Sewers were developed alongside cities about 6,000 years ago, and we have been mixing waste with water ever since. But there are too many of us for that practice to continue.
Side bonus: As these toilets become widely available and more people use them, the recycled waste products can begin replacing some of our fertilizer needs. That means we’ll have less need for the companies that mine for such products, including one that digs in central Florida and whose name rhymes with “prosaic.”
¡Viva la revolución del baño!
Contact Capt. Josh Olive at 941-276-9657 or Publisher@WaterLineWeekly.com.