Are volatile organic compounds (VOCs) causing problems in your household water supply in Helena, Lewis And Clark County? Understanding how VOCs behave and what water system data shows can help you decide what to test next and how to address this concern.
If seasonal water-table changes affect VOC movement near your well screen
Seasonal variations in water tables influence how solvent compounds move in groundwater. When water tables rise or fall, plumes of VOCs—volatile organics that may include various solvent compounds—can shift position relative to your well screen. This means that concentrations at your well intake might change over time, requiring repeat testing to monitor potential exposure.
If a granular activated carbon bed’s size depends on contact time over flow rate
Granular activated carbon (GAC) filtration effectively reduces VOCs by adsorbing volatile organics onto carbon surfaces. The performance of such filters relies primarily on contact time—the duration water remains in contact with the carbon bed—rather than simply the water flow rate. Adequate contact time is crucial for removing solvent compounds including those listed in government surveys, such as 1,1-dichloroethane, chloromethane, or MTBE, even when detected at low levels.
If you want to understand certified laboratory tests for VOCs and how to read results
Certified laboratory testing for VOCs reports measured concentrations typically in micrograms per liter (µg/L) or parts per billion (ppb). Test results distinguish detected levels from the laboratory’s reporting threshold, which is the lowest concentration reliably quantified. For example, Helena’s public water system monitoring found no detections above reporting limits for VOCs such as bromomethane or HCFC-22. Detecting a VOC below a health-based maximum contaminant level (MCL) is not a violation or necessarily harmful—it simply documents presence.
If you notice differences between public water system records and private well testing
Public water system records reflect the quality of water drawn from the shared source and treated centrally for thousands of users—in Helena’s case, serving over 32,000 people with surface water supplies. These records do not provide data about individual household plumbing or private wells. Therefore, monitoring results from Helena’s system do not substitute for private well testing, which is necessary to establish specific VOC levels at your home.
If you consider why VOC volatility matters for exposure beyond drinking water
Volatile organic compounds readily evaporate into air, making inhalation an important exposure route during activities like showering or dishwashing. While ingestion through drinking water is a primary concern, the volatilization of solvent compounds adds additional exposure possibilities. Understanding volatility helps in deciding treatment approaches that address both waterborne and airborne pathways.
Helena Water System’s data from 2013 to 2015, documented by the EPA’s Unregulated Contaminant Monitoring Rule (UCMR3), showed no VOC detections above reporting levels for multiple volatile organics. This public record covers the water source and system-wide monitoring but is not a direct test of individual household water. For specific concerns about solvent compounds or other VOCs, testing your water through a certified laboratory is recommended.
The Pentair VOCs & Industrial Chemicals Filter ships ready to configure and is designed specifically for reducing volatile organic compounds and industrial chemicals in home water supplies. This system uses granular activated carbon technology optimized for sufficient contact time to address solvent compounds effectively.
For more detailed government information on public water system monitoring in Helena, Lewis And Clark County, visit the EPA’s Safe Drinking Water Information System (SDWIS) public records.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2014-04-16. These figures describe the public water system's record, not the plumbing inside any individual building.
On record: EPA UCMR3 monitoring (2013-2015) for Helena Water System (MT0000241), MT: 74 results across 7 listed contaminants, 0 detections above the reporting level; nothing detected above the method reporting level
- ✓ 90-Day Money-BackNo restocking fees — return within 90 days.
- ✓ Manufacturer WarrantyGenuine Fleck · Pentair · VIQUA equipment.
- ✓ Free Expert SizingTalk to a specialist and buy the right system the first time.