By Robert Knight
The shocking term “explosive diarrhea” is in the current news stream.
Referring to an outbreak of fecal-borne disease (cyclosporiasis) propagated by consuming contaminated vegetables (e.g., Taco Bell lettuce?) and currently infecting thousands of people in at least nine different states, this is big news because it is evidence of the government’s inability to protect the public’s essential food supply (or at least tacos).
Explosive diarrhea was my first thought on July 16.
A few days earlier, WUFT FM (Gainesville’s PBS station) reported that Poe Springs, Alachua County’s only public recreational spring, was temporarily closed by Alachua County Parks and Recreation for swimming due to “poor water clarity”.
On July 16th, I received a text message from Bill Hawthorne, aquatic scientist at the Howard T. Odum Florida Springs Institute, with a photo he took that day at Poe Spring. The entire water surface of the spring pool was a nasty opaque yellow-green with no transparency and a shocking resemblance to the output of a certain lettuce born illness.
This event is not unprecedented. It is the direct and inevitable consequence of the failure to adequately protect our springs.
Florida’s environmental agencies have known with certainty for the past 26+ years that declining flows and increasing nitrogen pollution are impacting nearly every one of the state’s 1,000+ artesian springs.
Lower spring flows + higher nutrient concentrations add up to degraded springs water quality.
Protective Minimum Flows and Levels (MFLs) and Total Maximum Daily Loads (TMDLs) for nutrient pollutant concentrations at Poe and our other 30 Outstanding Florida Springs are required by state law, but effective springs protection and public welfare take a back seat to our state’s prioritization of urban, industrial, and agricultural development.
Here is a summary of recent history at Poe Spring (https://floridaspringsinstitute.org/santafeproject/):
- Poe Spring is a second magnitude spring with an historic (1917–1972) mean flow of 47 million gallons per day (MGD)
- There was no record of flow cessation or flow reversal at Poe Springs before the early 2000s
- Alachua County purchased Poe Springs and surrounding natural lands to establish a public park in 2004
- Due to long-term spring flow reductions and an extended 2-year drought in North Florida, Poe Spring flow was essentially zero in May 2012
- In June 2012, Tropical Storm Debbie delivered more than 11 inches of rainfall to North Florida
- The resulting 14-foot rise in Santa Fe River levels in the summer of 2012 initiated a massive flow reversal of tannic river water back-flowing through Poe Spring into the regional Floridan Aquifer, shutting down groundwater supplies in High Springs for several weeks because the tap water was brown
- In 2016, Poe Spring was designated as one of only 30 “Outstanding Florida Springs” an official state designation to insure enhanced protection
- Average Poe Spring flows during the past two decades are about 13 MGD, an average reduction of 72% compared to historic flows
- Nitrogen concentrations in Poe Springs have been measured as high as 1.76 parts per million, five times higher than Florida’s spring’s nitrate limit
- As of July 16, 2026, due to another typical period of low rainfall, flows have been near-zero for the past month at Poe Spring, resulting in its closure
Where is the pumped groundwater going that historically nourished the Santa Fe River and Poe Springs through a typical once-every-decade North Florida drought? And where are the elevated nutrients coming from?
The Florida Springs Institute’s Blueprint for Restoring Springs on the Santa Fe River lays out a detailed assessment of spring flow and water quality changes and describes a viable plan to return Poe Spring to its former health.
Spring flow restoration for Poe Spring and the combined Santa Fe River groundwater inputs from more than 50 springs will rely on reduced regional groundwater pumping.
The largest local groundwater users negatively affecting flows to the Santa Fe springs include Public Supply to cities of Gainesville, Alachua, High Springs, and Newberry. Private homeowners on both private and public supply wells, who shower their landscaped yards with nitrogen fertilizers and groundwater irrigation, must do their part to reduce groundwater depletion and pollution.
Groundwater and healthy Santa Fe spring flows are also diminished due to neighboring large pumping centers outside the Santa Fe springshed such as Jacksonville, and many dozens of smaller North Florida communities. Water Management Districts need to work together to solve excessive groundwater pumping that contributes to spring flow declines across district boundaries.
Phosphate, sand, and limerock mines; dairies and water bottling facilities; and thousands of agricultural irrigation wells also consume regional groundwater resources and recharge the Floridan Aquifer with harmful nutrients. Water Management Districts need to enact allocation restrictions for Florida’s largest groundwater permits if historic spring flows are going to be restored.
If we all work together, we can still save our springs.
Robert Knight, PhD. has studied Florida’s springs for 50 years and is President of the Howard T. Odum Florida Springs Institute in High Springs, Florida.