Understanding What Public Water System Records Reveal Versus Private Well Testing
Portsmouth Water Works Sampling
Public data from Portsmouth Water Works (NH1951010), serving 33,000 people through 7,200 connections, found no perchlorate detected above the reporting level of 4.0 micrograms per liter in 16 samples collected from 2003 to 2004. This federal monitoring was not a compliance test but an occurrence survey.
Difference From Private Well Testing
Public system records represent averages and conditions across the entire water supply; they do not provide perchlorate levels for individual homes. Testing your private well water is the only way to determine perchlorate presence and concentration specific to your property.
Key Information to Collect Before Evaluating Treatment Options
Confirm Water Source Type
Identify whether your water comes from the city’s surface water system or a private well, as treatment needs and test results will differ accordingly.
Obtain Recent Water Quality Tests
Gather laboratory reports detailing perchlorate or other relevant constituents from your own water supply to understand specific requirements.
Estimate Daily Water Usage
Record the average household daily water consumption to match treatment capacity to real demand.
Evaluating Treatment Capacity for Household Demand
Match Filter Capacity to Water Volume
Select equipment able to process your household’s daily water use without frequent regeneration or maintenance interruptions.
Consider Peak and Seasonal Usage Variations
Adjust capacity planning if your household water demand fluctuates seasonally or during peak times, ensuring consistent perchlorate management.
Interpreting Sampling Scope and the Impact of Sample Size
Number of Samples and Locations
The 16 sampler results for Portsmouth were from various points in the public water system; a limited sample size may not capture localized variations.
Implications of Small Sample Size
Fewer samples may reduce confidence in representing the full range of perchlorate levels across all connections.
Comparing Portsmouth Record to Nearby Counties
Avoid Overreading Regional Differences
Differences in perchlorate presence between Rockingham County and neighbors may reflect variations in water source and testing frequency rather than clear safety distinctions.
Use Local Data for Decisions
Rely on official data from Portsmouth Water Works and your own test to guide treatment rather than broad county comparisons.
Influence of Water Source Characteristics on Treatment Expectations
Surface Water Versus Groundwater
Portsmouth’s supply is surface water, which may have different perchlorate levels and treatment responses compared to well water.
Sample and Well Depth Considerations
For private wells, depth affects perchlorate presence; shallower or deeper wells may have differing levels requiring tailored treatment capacity.
For residential households in Portsmouth who measure their daily water demand, the Autotrol Perchlorate Filter ships ready to configure and offers capacity options to address perchlorate management matched to your specific usage.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2004-11-30. These figures describe the public water system's record, not the plumbing inside any individual building.
On record: EPA UCMR1 monitoring (2001-2005) for PORTSMOUTH WATER WORKS (NH1951010), NH: 16 results across 1 listed contaminants, 0 detections above the reporting level; nothing detected above the method reporting level