Central Florida Water Hardness by Utility: A Compiled Dataset from 2024 Consumer Confidence Reports

# Central Florida Water Hardness by Utility: A Compiled Dataset from 2024 Consumer Confidence Reports Last updated: September 2026

Central Florida's water hardness varies significantly across utility service territories, ranging from 6 grains per gallon (GPG) in parts of Volusia County to 22 GPG in portions of Kissimmee's KUA service area. The difference stems from geology: the Upper Floridan Aquifer, which supplies virtually all Central Florida utilities, passes through varying thicknesses of limestone depending on location. Utilities serving Osceola County draw from an aquifer zone with higher calcium carbonate concentrations than utilities serving northern Orange or Lake Counties. This compiled reference dataset maps hardness ranges across the utilities serving the Kissimmee-Orlando metro area, using data from 2024 Consumer Confidence Reports and USGS aquifer research. Homeowners can use this table to understand where their utility falls, what that means for appliances and water quality, and where to access the full CCR for their specific service address.

## How we compiled this dataset Every row in this dataset is drawn from one of three primary sources: the utility's 2024 Consumer Confidence Report (CCR), the utility's published water quality page, or USGS Scientific Investigations Report data on Upper Floridan Aquifer hardness by county. For utilities where we have verified CCR data (OUC and KUA), we report specific measured ranges. For utilities where the CCR is not centrally published or varies by pressure zone, we report a general range consistent with USGS aquifer data for that county and direct homeowners to the primary source. We do not interpolate or estimate numbers; where exact data was not available from a primary source, we say so and link the relevant CCR access point. Hardness can vary within a single utility's service territory depending on which wellfield supplies your zone, seasonal aquifer conditions, and whether your utility blends Floridan Aquifer water with treated surface water or uses reverse osmosis treatment at certain plants. The ranges reported here represent finished water as reported in CCRs, not raw aquifer water. The Water Quality Association hardness classification used throughout this article is: 0 to 3.5 GPG soft, 3.5 to 7 GPG moderately hard, 7 to 10.5 GPG hard, above 10.5 GPG very hard. Source: [WQA Water Quality Association](https://www.wqa.org/). ## The dataset: Central Florida water hardness by utility | Utility | Primary Service Cities (in service area) | Hardness Range (GPG) | Hardness Range (mg/L as CaCO3) | Disinfectant | CCR Source | |---|---|---|---|---|---| | OUC (Orlando Utilities Commission) | Orlando, Winter Park, Ocoee (portions), Windermere, Hunters Creek, Pine Castle, Buenaventura Lakes | 9 to 14 GPG | 155 to 240 mg/L | Chloramines | [ouc.com/water-quality](https://www.ouc.com/environment-community/water/water-quality) | | KUA (Kissimmee Utility Authority) | Kissimmee, Poinciana (portions) | 12 to 22 GPG | 205 to 376 mg/L | Chloramines | [kua.com/water-quality](https://kua.com/residential/water-quality/) | | Toho Water Authority | St. Cloud, Celebration, Poinciana (portions), Intercession City | Verify via CCR | Verify via CCR | Verify via CCR | [tohowater.com/water-quality](https://www.tohowater.com/water-quality) | | Orange County Utilities (OCU) | Apopka, Winter Garden, Ocoee (portions), some Clermont-area parcels | 8 to 14 GPG (blended; verify for your zone) | Approx. 137 to 240 mg/L | Verify via CCR | [orangecountyfl.net/WaterUtilities](https://www.orangecountyfl.net/EnvironmentEnergy/WaterUtilities) | | Polk County Utilities / City utilities | Davenport, Haines City, Lakeland area, Winter Haven | 6 to 14 GPG (varies by city utility) | Approx. 103 to 240 mg/L | Verify via CCR | Florida DEP CCR portal | | City of Clermont / Lake County utilities | Clermont, Leesburg, Mount Dora area | 8 to 14 GPG | Approx. 137 to 240 mg/L | Verify via CCR | Florida DEP CCR portal | | City of Deltona / Volusia County utilities | Deltona, DeLand area | 6 to 12 GPG | Approx. 103 to 205 mg/L | Verify via CCR | [floridadep.gov CCRs](https://floridadep.gov/water/source-drinking-water/content/consumer-confidence-reports) | Notes: - GPG = grains per gallon (the standard used by water treatment professionals) - mg/L as CaCO3 = the unit utilities typically report in Consumer Confidence Reports - Conversion: 1 GPG = approximately 17.1 mg/L as CaCO3 - "Verify via CCR" indicates that exact ranges were not centrally published at time of compilation and homeowners should consult their utility's current CCR ## What the hardness numbers mean for your home The Water Quality Association defines water above 10.5 GPG as "very hard." Most Central Florida utility customers fall into this category. Here is what that means in practical terms. Water heaters are the most affected appliance. Scale accumulates on heating elements and tank walls, reducing efficiency and shortening service life. A water heater in a home receiving 15 GPG water without any softening treatment will typically show significant scale buildup within two to three years. Tankless water heater manufacturers, including Navien, Rinnai, and Noritz, specify maximum hardness levels in their warranty terms because scale damage is the leading cause of early failure in tankless systems. Dishwashers and washing machines are the second most affected category. Scale deposits on internal components, and the reduced effectiveness of soaps and detergents in hard water means more product is required to achieve equivalent cleaning results. At 9 to 14 GPG (the OUC range), homes benefit from water softening, particularly if they have tankless water heaters or newer appliances. At 12 to 22 GPG (the KUA range in Kissimmee), softening is necessary rather than optional for appliance protection. The scale formation rate at 20 GPG is roughly three times that at 7 GPG. For drinking water, hardness itself is not a health concern. The minerals driving Central Florida's hardness (calcium and magnesium) are not regulated contaminants. The concern for drinking water quality in Central Florida is disinfection byproducts and, to a lesser extent, PFAS at levels above the EPA's April 2024 maximum contaminant levels of 4 parts per trillion for PFOA and PFOS. Source: [EPA PFAS standards](https://www.epa.gov/sdwa/and-polyfluoroalkyl-substances-pfas). ## Why Osceola County water is harder than Orange County water The difference between KUA's 12 to 22 GPG and OUC's 9 to 14 GPG has a geological explanation rooted in the structure of the Upper Floridan Aquifer itself. According to USGS Scientific Investigations Report 2010-5070, which documents the hydrogeology of the Floridan Aquifer System, Orange and Osceola Counties draw from the same aquifer but from different zones within it. The Upper Floridan Aquifer is a sequence of carbonate rock (limestone and dolostone) that was deposited over millions of years. The thickness of the highly permeable, calcium carbonate-rich Avon Park Formation is greater in Osceola County than in much of Orange County. Water that spends more time in contact with thicker limestone deposits dissolves more calcium carbonate, arriving at the wellhead with higher hardness. KUA's service area draws from aquifer zones where the confining layers are thinner and the aquifer rock contains higher concentrations of calcium carbonate. OUC, serving the Orlando area, also draws from the Upper Floridan Aquifer but from a section where surface recharge patterns and aquifer thickness produce somewhat lower mineral concentrations in finished water. Source: [USGS SIR 2010-5070](https://pubs.usgs.gov/sir/2010/5070/). Orange County Utilities mitigates this further by blending Floridan Aquifer water with treated water processed through reverse osmosis at its Southern Water Treatment Plant, which dilutes the mineral content before distribution to some service zones. ## Finding your utility's Consumer Confidence Report Every public water system in the United States serving 25 or more people is required to publish an annual Consumer Confidence Report (CCR) by July 1 each year. The CCR reports measured levels of regulated contaminants, the hardness of finished water, and the disinfectant used. For utilities listed in this table, the direct links above go to either the CCR page or the utility's water quality page where CCRs are posted. For utilities not listed or for homeowners served by smaller local systems (certain Polk County cities, Orange County sub-districts, or private community water systems), the Florida Department of Environmental Protection maintains a centralized CCR portal where you can search by system name or county: [Florida DEP Consumer Confidence Reports](https://floridadep.gov/water/source-drinking-water/content/consumer-confidence-reports) Note that CCR data is reported by calendar year and typically covers average levels across the full distribution system. Hardness at your tap may vary slightly from the CCR average based on your zone, seasonal aquifer changes, and your home's distance from the treatment plant. ## What to do about Central Florida hard water If your home is in the OUC or KUA service area, the hardness range your utility reports is sufficient to assess treatment needs. If you are served by Toho, OCU, or a Polk or Lake County utility, your first step is pulling your utility's CCR to confirm the specific hardness for your zone. For homes receiving water above 7 GPG (which is most of Central Florida), a whole-house water softener provides the most comprehensive protection for appliances, plumbing, and water heaters. For drinking water quality concerns including disinfection byproducts, chloramines, or PFAS, a whole-house carbon filtration system or a point-of-use reverse osmosis system at the kitchen tap is the appropriate treatment. Pure Agua Enterprises has served Central Florida homeowners for more than 10 years, with installations across Orange, Osceola, Polk, Lake, and Volusia Counties. A free in-home water test takes 30 minutes and gives you exact hardness and contaminant readings for your specific address, not a utility average. Call us or use the form below to schedule.