This week, you must decide how to respond to 1,2,3-trichloropropane (1,2,3-TCP) concerns in your household water when your current treatment setup is no longer sufficient.
If you want to understand how state and federal guidelines differ on 1,2,3-TCP
Smith County’s water is served by Southern Utilities, which uses surface water sources and falls under the EPA’s regulatory framework. According to the EPA’s Safe Drinking Water Information System (SDWIS), this public water system has recorded no health-based violations from 1,2,3-trichloropropane or any other contaminant, indicating compliance with federal safety standards.
However, California sets a stricter guideline of 5 nanograms per liter (ng/L) — equivalent to 0.005 micrograms per liter (µg/L) or parts per billion (ppb) — as a state-level advisory for 1,2,3-TCP in drinking water. The absence of a federal maximum contaminant level (MCL) means EPA does not enforce a nationwide limit. This difference means water meeting EPA requirements may still have 1,2,3-TCP levels above California’s advisory threshold, which some households consider when evaluating water quality.
If you want to know how historic agricultural fumigants relate to current 1,2,3-TCP occurrences
1,2,3-trichloropropane is a chlorinated solvent historically used as a soil fumigant primarily between the 1950s and 1980s. Its persistence and mobility in soil allow it to leach deeply into groundwater decades after its initial application. Although Smith County’s public water system relies on surface water, legacy contamination can reach sources via groundwater inflows or runoff into reservoirs.
If you want to trace how 1,2,3-TCP enters your regional water supply
Sampling performed under EPA’s Unregulated Contaminant Monitoring Rule 3 (UCMR3) between 2013 and 2015 detected no 1,2,3-trichloropropane above the reporting level of 0.03 micrograms per liter (30 parts per trillion) in Southern Utilities’ surface water supply. This monitoring effort involved 46 measurements, none showing detectable TCP. The findings mean that if 1,2,3-TCP is present locally, it remains below these detectable levels, or dilution and treatment reduce it significantly before reaching taps.
If you want to interpret monitoring results as a homeowner
Given no detections above the EPA reporting level in Smith County’s public system, your household water likely contains TCP at very low or undetectable concentrations. Still, regional monitoring sets a context rather than characterizing individual wells or household taps. To know your home's water specifically, a private laboratory water test focused on 1,2,3-TCP detection at or below 0.03 µg/L would be necessary. Such testing clarifies if existing treatment systems suffice or if supplemental approaches are warranted.
If you want to explore treatment options when current equipment is overwhelmed
When existing home water equipment cannot keep pace with removing or controlling 1,2,3-trichloropropane, one documented technology is the Pentair 1,2,3-TCP Filter. This system ships ready to configure and employs filtration media scientifically proven to intercept and neutralize chlorinated solvents like TCP at low concentrations. It provides a path forward when monitoring indicates TCP presence beyond household tolerance or current equipment capability.
Deciding to supplement your water treatment with a Pentair solution can target your specific demand after you measure or confirm 1,2,3-TCP concentrations. This targeted approach fits households in Smith County seeking effective control of this chlorinated solvent under conditions where existing equipment no longer maintains desired performance.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2013-08-27. These figures describe the public water system's record, not the plumbing inside any individual building.
On record: EPA UCMR3 monitoring (2013-2015) for Southern Utilities (TX2120063), TX: 46 results across 1 listed contaminants, 0 detections above the reporting level; nothing detected above the method reporting level