Understanding What a Certified Sulfide Water Test Report Shows
A certified laboratory test for sulfide in water typically reports the measured concentration in milligrams per liter (mg/L). This numeric result represents the amount of sulfide detected during the analysis. Results may include values below the reporting limit, which means sulfide was not measurable at or above the lab's detection capability. For instance, a report may read “0.0 mg/L” when sulfide is not detected or indicate a small positive number when it is present in trace amounts.
How Hillsborough County Public Water System Records Differ from Private-Well Testing
Public water system records for sulfide reflect the sampling of several wells across the aquifer, not individual homes' water quality. In Hillsborough County’s aquifer 112SRFD, the U.S. Geological Survey sampled three wells between April 2010 and June 2011. These records provide a range of sulfide levels found in sampled wells but do not represent any particular well or household. Private-well owners must conduct their own tests to determine sulfide concentration at their tap.
Seasonal and Multi-Year Trends in Hillsborough County Sulfide Data
The USGS data set includes samples taken over a 14-month period, spanning spring and early summer months across two years. The sulfide concentration readings ranged from 0.0 to 0.1 mg/L, with a median of 0.0 mg/L. This range indicates occasional low-level presence of sulfide in the aquifer, but consistently below any federal thresholds for health concerns. The sampling depth of these wells ranged from 20 to 60 feet, indicating the sulfide levels are representative of typical shallow groundwater sources in the area.
Distinguishing Sulfur Smell From Other Similar Household Water Odors
The sulfur smell — often described as a rotten-egg odor — is primarily caused by sulfide compounds dissolved in the water. It is important to differentiate this from odors caused by bacteria, chlorination byproducts, or other chemical contaminants, which may have different sources and treatment needs. Sulfide odor usually disappears upon aeration or treatment but bacterial odors require disinfection and other approaches.
How Well Depth and Source Type Affect Expectations for Sulfur Smell
Wells in Hillsborough County ranging from 20 to 60 feet deep sampled for sulfide show generally low levels, but deeper wells or those drawing from different aquifers may have different results. Private wells tapping deeper formations may experience varying sulfide levels depending on geochemical conditions. Residents with existing water treatment equipment that struggles to keep up with sulfur odors may consider technologies designed specifically to address sulfide-related odor.
What Not to Conclude from the Regional Sulfide Data
Although sulfide was detected in all three USGS-sampled wells in this area, none exceeded federal limits, and these findings cannot be applied to any individual household’s water without direct testing. Detection alone does not signify unsafe water. Residents should obtain a certified laboratory test of their own water to understand specific concentrations before selecting treatment options. For households facing sulfur smell that their current equipment cannot fully manage, the C-Series Rotten-Egg Sulfur Smell Filter ships ready to configure and is designed to reduce sulfide-related odors effectively.
Where this information comes from
Source: USGS groundwater sampling. Sampled 2011-06-06. These figures describe groundwater sampled in this area. They are not a test of any individual private well - only a test of that well can establish its own water.
On record: U.S. Geological Survey sampling of Sulfide in the 112SRFD aquifer (Hillsborough County): 3 results from 3 wells, median 0.0 mg/L, range 0.0-0.1 mg/L; none above any federal threshold