When trying to understand if volatile organic compounds (VOCs) affect your household water in Montgomery County, PA, it's important to recognize what regional water system data can and cannot tell you. Data from public water systems reflect samples taken in many locations across the network, not from any one home. Meanwhile, VOC presence varies greatly depending on local conditions including groundwater flow and plumbing. This page addresses common beliefs and contrasts them with EPA monitoring results for the Aqua PA Main System serving Montgomery County.
How Seasonal Water-Table Changes Move a Solvent Plume Relative to a Well Screen
There is a common view that solvent plumes in groundwater remain static or always move toward the well screen. Actually, seasonal factors such as rainfall and groundwater recharge cause water tables to rise and fall, shifting a plume's position vertically and horizontally. This movement means that VOC levels in a well can fluctuate throughout the year based on where the plume sits relative to the intake screen. EPA's monitoring of the Aqua PA system reflects multiple samples over several years, capturing some of this variability but not pinpointing conditions at any one residence.
Why Volatility Matters: Showering, Dishwashing and Inhalation Routes Versus Drinking
Volatile organic compounds like 1,1-dichloroethane are called volatile because they readily evaporate from water into air. This volatility means exposures are not limited to ingesting water but also include inhalation during showering, washing dishes, or cooking. While EPA data for Montgomery County's Aqua PA system found detections of 1,1-dichloroethane up to 0.138 micrograms per liter (µg/L, or parts per billion), it is crucial to note that these values represent measurements, not health-based violations. Understanding this helps focus on comprehensive VOC treatment that reduces the compound in all household water uses.
The Role of Plumbing Material and Age, Separate from the Source Water
Another mistaken belief is that all VOC presence comes directly from source water. However, plumbing materials and the age of household pipes can independently affect water quality. Older pipes may absorb or release volatile organics, altering their concentrations independently of municipal supply. Since EPA records pertain only to the public system’s source water and distribution, individual plumbing conditions require specific water testing at the point of use to confirm actual VOC levels in household water.
Which Fixtures, Appliances or Processes Are Affected First and Why
Some fixtures like kitchen sinks, ice makers, and showerheads often show the effects of VOCs earlier than others. This is because these points of use involve aeration or heating, which encourage volatile compounds to transfer from water to air quickly. Understanding this can help identify which parts of the home may benefit most from targeted treatment. Since Aqua PA’s system monitoring detected low-level VOCs such as 1,1-dichloroethane but none of the other listed VOCs at reportable levels, consideration of specific treatment for drink and wash water is prudent in some households.
How a Gasoline Release Differs from a Dry-Cleaning Release in What It Leaves in Groundwater
Communities sometimes confuse VOC profiles stemming from gasoline leaks with those from dry-cleaning solvents, but their chemical signatures differ significantly. Gasoline contamination often involves compounds like MTBE, which EPA found not detected above reporting levels in Montgomery County water. Dry-cleaning solvents may include 1,1-dichloroethane and related chlorinated compounds, detected sporadically by Aqua PA’s monitoring. This distinction matters because treatment approaches and monitoring focus vary depending on the source of contamination.
What You Should Not Conclude from Montgomery County Water System VOC Data
The EPA’s unregulated contaminant monitoring data for the Aqua PA Main System demonstrate that some VOCs such as 1,1-dichloroethane were detected at low concentrations, while many others were not detected above reporting thresholds. No federal maximum contaminant levels (MCLs) apply to these unregulated VOCs, and their detection is not an indication of contamination or unsafe water. Importantly, these regional data do not reveal levels in your specific well or household plumbing. To understand your home's situation, independent testing of your actual water supply is necessary.
For addressing VOC concerns identified through testing, specialized treatment systems such as the C-Series VOCs & Industrial Chemicals Filter are designed to reduce volatile organic compounds effectively throughout household water. This equipment ships ready to configure and uses carbon filtration tailored to VOC removal, helping protect household water quality from solvent compounds detected in regional water sources.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2013-10-31. These figures describe the public water system's record, not the plumbing inside any individual building.
On record: EPA UCMR3 monitoring (2013-2015) for Aqua PA - Main System (PA1460073), PA: 363 results across 7 listed contaminants, 7 detections above the reporting level; no federal MCL for these UCMR-listed VOCs