Limestone County, Alabama: drinking water report. Limestone County in northern Alabama borders Madison County and has a population of about 105,000, with…
Limestone County in northern Alabama borders Madison County and has a population of about 105,000, with Athens as the county seat. The county draws water from the Elk River and Wheeler Reservoir on the Tennessee River. Rapid growth fueled by Huntsville's expanding job market is pushing residential development into formerly agricultural areas, and that transition affects both water demand and water quality as farmland becomes subdivisions.
Limestone County's proximity to the Huntsville-Decatur industrial corridor means it shares some of the region's environmental concerns. The 3M facility in Decatur (adjacent Lawrence County) has been a major source of PFAS contamination in the Tennessee River system. According to ADEM's 2024 PFAS monitoring report, PFAS compounds have been detected in the Tennessee River at concentrations of 10-30 ppt at monitoring points used by Limestone County systems – above the EPA's MCL of 4 ppt for PFOS.
The Elk River carries agricultural runoff from the northern Alabama dairy and livestock country. A 2023 ADEM assessment documented elevated nutrient levels in several Elk River tributaries within Limestone County, reflecting the agricultural land use upstream.
The PFAS contamination affecting the Tennessee River system is a regional issue driven by upstream industrial sources, not by anything within Limestone County's control. Household filtration is the most direct action available to residents.
Check your water for the latest monitoring data. For PFAS from the Tennessee River system, reverse osmosis is the most effective household treatment. Our water filter guide compares systems by certified PFAS removal rates. Pull your detailed report for trends, and visit our Alabama page for statewide context.
Drinking water is one exposure route. These federal datasets also cover Limestone County, AL.
The EPA places Limestone County, AL in Zone 1 - the EPA's highest-risk category, where the predicted average indoor radon level is above 4 pCi/L. Zone maps predict an area's radon potential from geology and existing indoor readings; they say nothing about a specific house. Testing is the only way to know your own level.
29% of homes in Limestone County, AL were built before 1980, and 5% before 1950. Residential lead paint was banned in 1978, so housing age is the strongest available proxy for lead-paint exposure. This describes the county's housing stock, not any one home.
Modelled annual fine-particle pollution (PM2.5) in Limestone County, AL averages 7.8 µg/m³, within the EPA's annual standard of 9 µg/m³. These are CDC modelled county estimates rather than readings from a specific monitor.
How radon zones work · Air quality by county · Lead exposure guide