Where Jacksonville's Tap Water Comes From: 10 Questions About the Floridan Aquifer, 120 Million Gallons and JEA

JACKSONVILLE, Fla. - Jacksonville's drinking water comes from the Floridan aquifer, an underground water source that runs through limestone formations hundreds of feet below the surface. JEA draws water from wells reaching approximately 1,000 feet underground, treats it at water treatment plants and distributes it through pipelines to homes and businesses. Along the way it is aerated to remove its natural sulfur odor and disinfected with chlorine.

JEA delivers more than 120 million gallons of water each day across its service territory. The utility performs an average of 45,000 water tests annually and monitors its treatment systems around the clock. Its 2025 Water Quality Report explains how that water reaches customers, what the utility tests for and why some households notice mineral deposits or changes in taste and odor.

1. Where does Jacksonville's drinking water come from?

JEA gets its drinking water from the Floridan aquifer, which supplies water throughout Northeast Florida. The utility describes the aquifer as "a gigantic underground river that courses through limestone formations many hundreds of feet underground." Its wells draw water from approximately 1,000 feet below the land surface.

The St. Johns River is not JEA's drinking water source. Instead, JEA relies on underground wells connected to water treatment plants and distribution systems. Those facilities move water from the aquifer to customers across several service areas.

2. How much water does JEA deliver every day?

JEA delivers more than 120 million gallons of water daily through its water system. That system includes wells, water treatment plants, distribution pipelines and customer meters. Each component plays a role in moving water from underground sources to service connections.

JEA also operates multiple water distribution grids rather than relying on a single distribution network. The grid system provides backup during emergencies and when water treatment plants undergo maintenance. This arrangement allows the utility to maintain service through its interconnected facilities.

3. How does underground water become tap water?

The process begins when deep well turbine pumps bring water from the Floridan aquifer to the surface. Well headers carry that water toward treatment plants, where aerators remove the sulfur odor naturally associated with the source water. Treatment facilities then store the water in reservoirs until it is needed.

JEA disinfects the water with chlorine before delivering it through its pipelines. Service pumps move treated water into transmission mains, which connect to distribution mains serving customers. Service connections and meters complete the route from the treatment facilities to individual properties.

4. Why does Jacksonville's water sometimes have a sulfur smell?

Water drawn from the Floridan aquifer can contain compounds that produce a sulfur odor. JEA uses aeration at its treatment plants to remove that odor before sending water into its distribution system. This treatment is one of the steps between pumping water from underground wells and delivering it to customers.

JEA also uses ozone at two of its water treatment plants. The ozone treatment helps remove sulfides and improves the water's taste and odor. These measures address characteristics of the source water before it enters the distribution network.

5. How does JEA monitor water quality and treatment?

JEA performs an average of 45,000 water tests each year and tests for more than 100 contaminants. Its annual water quality report includes tables showing contaminants detected during the reporting period. The 2025 report covers testing conducted from January 1 through December 31, 2025.

The utility also uses a system called Supervisory Control and Data Acquisition, or SCADA, to monitor and control its treatment operations remotely. SCADA tracks water pressure, flow, reservoir levels, chlorine levels and pH at JEA water plants 24 hours a day. This technology gives the utility continuous information about conditions throughout its treatment operations.

6. Which Jacksonville-area communities receive JEA water?

JEA's Major Grid supplies most of Duval County and the northwestern portion of St. Johns County. The utility also serves the Yulee area, Mayport and communities along A1A from Ponte Vedra south to Vilano Beach. A small area of Palm Valley receives water through an interconnection with the St. Johns County Utility Department.

JEA identifies six distribution grids: Major, Mayport, Lofton Oaks, Ponte Vedra, Ponce de Leon and Palm Valley. These grids organize service across different portions of the utility's territory. They also provide backup capabilities during emergencies or maintenance at water treatment plants.

7. What potential contamination sources exist near JEA's wells?

Florida's Department of Environmental Protection conducted source water assessments in 2025 that identified potential contamination sources near JEA wells. The sources included landfills, fuel storage tanks, dry cleaners and wastewater disposal areas. The assessments evaluated susceptibility to potential contamination rather than reporting that those sources had contaminated the drinking water.

The Major Grid assessment identified 173 potential sources and assigned a low-to-moderate susceptibility rating. Lofton Oaks had 11 potential sources, Ponce de Leon had four, and Mayport and Ponte Vedra each had two. All four of those grids received low susceptibility ratings.

Residents can review the state's source water assessment information through the Florida Department of Environmental Protection at prodapps.dep.state.fl.us/swapp. The assessments provide information about potential contamination sources associated with individual water supply areas. They are separate from the contaminant testing results published in JEA's annual water quality report.

8. Why does Jacksonville have hard water?

JEA explains that water becomes "hard" when it contains high concentrations of dissolved minerals, primarily calcium and magnesium. Florida's underground water sources naturally contain dissolved minerals, which can remain in drinking water after treatment. According to JEA, calcium and magnesium in hard water do not present a health risk.

Hard water can leave visible spots or mineral deposits on household surfaces. JEA recommends white vinegar to clean those spots. Customers can also check the utility's ZIP code hardness table at jea.com/hardness for information about water hardness in their areas.

9. What does JEA's water quality report say about limits and treatment?

JEA's 2025 Water Quality Report explains that Florida's source water naturally contains relatively high concentrations of dissolved minerals. Some secondary contaminants exceeded limits established for aesthetic qualities such as appearance, smell or taste. JEA identifies those exceedances as aesthetic concerns rather than health risks.

One example involves the St. Johns Forest water treatment plant in the Major Grid. That facility has a state waiver permitting sulfate concentrations of up to 500 milligrams per liter. The waiver appears in the report's discussion of water quality characteristics and secondary standards.

JEA publishes its water quality report annually under requirements established by the 1996 Safe Drinking Water Act Amendments. The report includes detected contaminants rather than listing every contaminant the utility tests for. Customers seeking additional drinking water information can contact the Environmental Protection Agency's Safe Drinking Water Hotline at (800) 426-4791.

10. Can the Floridan aquifer supply Jacksonville's water indefinitely?

JEA says the Floridan aquifer is not an unlimited water source. The utility has developed its H2.0 program to purify reclaimed water to drinking-water quality and use it to replenish the aquifer. The initiative addresses water conservation by developing an additional way to return purified water to the underground supply.

The planned H2.0 Purification Center will have the capacity to purify 1 million gallons of water each day. The facility will also include a visitor area and a training facility. JEA provides additional information about the program at jeaonewater.com.

The program represents one part of JEA's approach to managing its underground water source. While its existing wells and treatment plants supply more than 120 million gallons daily, the utility acknowledges that the aquifer has limits. Its H2.0 project focuses on replenishing that source through advanced purification of reclaimed water.

How we did this

This explainer uses information from JEA's 2025 Water Quality Report, available at jea.com/WQR2025 and reviewed October 26, 2026. The report provides the figures for daily water delivery, annual testing, treatment methods, distribution grids, water hardness and source water assessments conducted by the Florida Department of Environmental Protection. Additional resources identified in the report include the state's source water assessment website at prodapps.dep.state.fl.us/swapp, JEA's hardness information at jea.com/hardness and the H2.0 program website at jeaonewater.com.