Uranium is a naturally occurring heavy metal that dissolves into groundwater as water moves through uranium-bearing rock formations. In Central Florida, the Floridan Aquifer System supplies drinking water to virtually all public utilities across the region, including those serving Kissimmee, Orlando, St. Cloud, and Winter Park. The aquifer draws from the Ocala Limestone formation, which contains uranium deposited by historic phosphate-bearing sediments. The U.S. Environmental Protection Agency sets a Maximum Contaminant Level of 30 micrograms per liter for uranium in public drinking water under the Radionuclides Rule. Uranium levels in groundwater vary by location and by water system, so the reliable number for your household is the one in your utility's Consumer Confidence Report.
Concerned about uranium or other radionuclides in your water? Pure Agua Enterprises offers free in-home water testing throughout Kissimmee, Orlando, St. Cloud, Winter Park, Altamonte Springs, and all of Central Florida. Schedule your free water test today.
Where does uranium in Central Florida's water supply come from?
The Floridan Aquifer System underlies all of Florida and extends into Georgia, Alabama, and South Carolina. It is a karst limestone formation, meaning water moves through dissolved cavities and fractures in carbonate rock rather than through porous sediment. As that water moves through the rock, it dissolves trace minerals, including uranium deposited by ancient phosphate-bearing sediments.
The phosphate belt running through Polk, Hillsborough, Hardee, and surrounding counties is the primary concentration zone, but the mineralogy of the broader aquifer system means uranium is present, at varying levels, throughout the formation that supplies Altamonte Springs, Sanford, Oviedo, Apopka, and the rest of the Central Florida region.
Unlike contaminants introduced by industrial activity, uranium in the Floridan Aquifer is entirely natural. That does not mean it is harmless: at high doses, uranium acts as a chemical toxin affecting the kidneys, independent of its radioactive properties. The EPA Radionuclides Rule establishes the MCL based on both the chemical and radiological risks associated with long-term ingestion.
What is the EPA's MCL for uranium in drinking water?
The EPA Maximum Contaminant Level for uranium in public drinking water is 30 micrograms per liter, also written as 30 parts per billion or 30 ppb. This standard was established under the Radionuclides Rule (40 CFR Part 141) and applies to all community water systems in the United States. The full regulatory text and supporting documentation are available at epa.gov/dwreginfo/radionuclides-rule.
The EPA set the Maximum Contaminant Level Goal (MCLG) for uranium at zero, acknowledging that no threshold below which uranium poses no health risk has been established. The MCL of 30 micrograms per liter represents a practical regulatory limit based on what treatment can feasibly achieve for large public water systems at reasonable cost.
The World Health Organization sets the same threshold: its Guidelines for Drinking-water Quality, 4th edition, establish a guideline value of 30 micrograms per liter for uranium, citing both the nephrotoxic (kidney-damaging) and radiological risk basis (WHO Guidelines for Drinking-water Quality, 4th edition). The alignment between the EPA MCL and WHO guideline reflects the strength of the underlying health evidence.
Long-term ingestion of water above the MCL is associated with increased kidney disease risk from the chemical toxicity of uranium, and some research links long-term low-level uranium exposure to elevated cancer risk from its radiological activity.
How much uranium is in Central Florida drinking water?
The USGS National Water Information System (NWIS) compiles water-quality monitoring data from wells, springs, and surface water across the country. Uranium concentrations in the Floridan Aquifer depend on local geology, well depth, and proximity to phosphate-bearing formations.
Uranium levels differ from one wellfield and one water system to the next, so the only authoritative number for your household is the uranium result in your own utility's annual Consumer Confidence Report (CCR). That applies equally in Winter Garden, Davenport and Lakeland. Private well owners are not covered by a CCR and should have their water tested for uranium by a state-certified laboratory.
How often do Florida utilities exceed the uranium MCL?
The uranium MCL is 30 micrograms per liter. The quickest way to see whether your utility has exceeded it is its compliance record and Consumer Confidence Report, described below.
Florida utilities serving communities in Apopka, Winter Garden, Clermont, Davenport, and Lake Mary are required to test for uranium under the Radionuclides Rule and report results annually in their Consumer Confidence Reports. A CCR violation requires the utility to notify customers and implement treatment or alternative sourcing within a specified timeframe.
The Florida DEP Drinking Water Information System tracks compliance data for all regulated systems in the state. You can request your utility's compliance history and current CCR from the utility or the Florida Department of Environmental Protection. The EPA's national CCR portal at epa.gov/ccr provides an additional search tool covering all regulated systems by zip code.
This article on PFAS contamination in Central Florida covers a separate category of regulated contaminants in the same region, and our Central Florida water hardness dataset documents the hard water conditions that also come from the Floridan Aquifer geology.
How do I find uranium data for my utility?
Every community water system in Florida serving more than 25 people year-round is required to issue an annual Consumer Confidence Report. The CCR covers the prior calendar year's water quality testing results, including radionuclides such as uranium, radium, and gross alpha particle activity.
To find uranium data for your utility:
- Visit the EPA's CCR portal at epa.gov/ccr and search by zip code.
- Look up your water system on the EPA's local drinking water information page at epa.gov/ground-water-and-drinking-water/local-drinking-water-information.
- Go directly to your utility's website. Major Central Florida utilities with published CCRs include:
- OUC (Orlando Utilities Commission): ouc.com/about/water-services
- Toho Water Authority (Kissimmee, St. Cloud, Poinciana): tohowater.com/waterquality
In the CCR, look for the section labeled "Radioactive Contaminants." The report will list the contaminant name, the MCL, and the highest level detected in that reporting year. A result reported as "ND" means non-detect at the laboratory's detection limit. A result at or near 30 micrograms per liter warrants a conversation about point-of-use treatment.
If you are on a private well in Kissimmee, St. Cloud, Oviedo, Sanford, or anywhere else in Central Florida, no regulatory reporting applies to your well. You would need to arrange laboratory testing directly. Our guide to radium in Florida tap water covers the broader radionuclide picture for private well owners.
What treatment removes uranium from drinking water?
Reverse osmosis is the most effective point-of-use technology for uranium reduction in drinking water. A properly specified and maintained under-sink RO unit reduces uranium from levels near the MCL to concentrations well below the regulatory limit at the tap.
Systems used for radionuclide reduction, including uranium, should be certified to NSF/ANSI Standard 58, the standard that covers reverse osmosis drinking water treatment systems. Certification to NSF 58 means an independent laboratory has verified that the system performs as claimed for the contaminants listed on its performance data sheet.
Standard activated carbon filters, water softeners, and basic sediment filtration do not remove uranium. A water softener addresses Central Florida's hard water and reduces scale, but it exchanges calcium and magnesium for sodium rather than removing dissolved heavy metals or radionuclides. For uranium specifically, reverse osmosis is the technology the evidence supports.
An under-sink reverse osmosis system installed at the kitchen faucet provides treated water for drinking and cooking. For households where total dissolved solids, radionuclides, PFAS, or nitrates are a concern across multiple taps, a whole-home system paired with an under-sink RO unit is a comprehensive approach. The reverse osmosis systems page covers the options available from Pure Agua for Orlando, Kissimmee, Winter Park, Lake Mary, and surrounding communities.
FAQ: Uranium in Central Florida drinking water
Does uranium in Central Florida water come from industrial activity?
No. The uranium in the Floridan Aquifer is entirely natural, originating from the Ocala Limestone formation and its associated phosphate-bearing sediments. While phosphate mining can disturb these formations and influence local groundwater, the uranium present in the aquifer system predates any industrial activity.
Is Central Florida tap water safe to drink if uranium is present?
A utility that reports uranium below the EPA MCL of 30 micrograms per liter is operating within federal regulatory limits, and your Consumer Confidence Report gives that number for your system. Whether to use additional point-of-use treatment is a personal decision that depends on your utility's reported levels, your household's health situation, and your tolerance for trace contaminants. Consulting your utility's current Consumer Confidence Report gives you the actual measured level for your service address.
How do I test my well for uranium?
Contact a Florida-certified water testing laboratory and request a radionuclide panel that includes uranium, gross alpha, and combined radium. The Florida DEP maintains a list of certified laboratories. A basic uranium test typically costs between $30 and $80 depending on the laboratory. If you have Pure Agua perform a free in-home water test, our technician can discuss which laboratory tests are appropriate based on your well's location and depth.
Does boiling water remove uranium?
No. Boiling water does not remove uranium. Because boiling reduces water volume through evaporation, it can actually concentrate dissolved minerals, including uranium, in the remaining water. Reverse osmosis is the correct treatment approach for uranium reduction.
Can a standard water filter pitcher remove uranium?
Most pour-through filter pitchers use activated carbon, which does not remove uranium. Some pitcher filters are certified to reduce specific contaminants, but uranium removal requires a reverse osmosis membrane. Check the performance data sheet for any filter product to confirm what contaminants it is certified to reduce before relying on it for uranium.
How often do utilities test for uranium?
Monitoring frequency depends on prior results. Under the EPA Radionuclides Rule, the baseline for a community water system is one uranium sample every three years, which is what applies when past results averaged above half the MCL but no higher than the MCL. States may reduce that to once every six years when the average was at or above the detection limit but no higher than half the MCL, and to once every nine years when the average was below the detection limit. A system whose average result is above the MCL must sample quarterly until it has four consecutive quarters at or below the MCL (40 CFR 141.26). Your utility's current CCR will note when the most recent uranium test was conducted.
Ready to learn what is in your water? Pure Agua Enterprises provides free in-home water testing for residents throughout Kissimmee, Orlando, St. Cloud, Winter Park, Altamonte Springs, Lake Mary, Sanford, Oviedo, Apopka, Winter Garden, Clermont, Davenport, Lakeland, Leesburg, and Deltona. Schedule your free water test today.
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