The Lisbon Water Department, serving 6,643 residents in Androscoggin County through 2,657 connections, sources water from groundwater and has one EPA health-based violation on record. This fact sheet outlines what the system's water quality record means for households experiencing whole-home drinking water issues when existing equipment is struggling to keep up.
Certified Laboratory Test Results Concepts
Lead 90th Percentile as a Distribution Measure
EPA sampling in Lisbon’s system reported a lead 90th percentile at 0.0016 mg/L in 2025, which is a plumbing distribution figure—not a direct measure of source water. This percentile shows the concentration below which 90% of samples fall, helping identify potential lead presence but not confirming individual home levels.
Understanding Treatment Process Codes
The recorded treatment process codes (348, 421, 445) indicate the types of treatments applied at the system level, without specifying functional details. These reflect steps to address contaminants but don’t detail performance in private home plumbing or specific tap water.
Effects of Groundwater and Sampling Depth
Source Water vs Distribution Sampling
Government figures come from groundwater-sourced water, yet contaminant levels in homes can differ due to plumbing materials and usage patterns. A certified lab test from your tap water is the only way to know your home's actual concentration.
Sample Depth Variation
Variation in sample depths across the system can influence detected levels; deeper wells may provide different quality than shallower ones, so system averages may not reflect all household experiences.
Information to Record Before Seeking Treatment Advice
Your Water Test Results
Obtain a certified laboratory water test for your tap water, noting reported concentrations and any actionable contaminants.
Existing Equipment Capacity and Performance
Document current equipment capabilities and observed issues, especially if treatment cannot keep up with household demand.
Household Water Usage
Calculate your daily water consumption to assess whether treatment capacity aligns with your needs.
Interpreting System Measurements Versus Regulatory Standards
Detected Levels and Health-Based Violations
The system’s record shows one health-based violation but does not equate to unsafe water at all connections. Detection of a constituent does not automatically indicate a violation or health risk.
Aesthetic Secondary Standards Are Not Safety Measures
Standards relating to taste, staining, or corrosivity are not safety limits and should not be confused with health concerns.
Evaluating Treatment Capacity for Your Household
Matching Grain Capacity to Demand
The C-Series Whole-Home + Drinking Combo System offers a grain capacity of 32,000, designed to meet significant household demand and provide effective treatment when existing equipment falls short.
Considering Peak and Daily Use
Compare your household’s average and peak water usage to the treatment capacity to ensure the system can keep up without compromising water quality.
Example: Reading the Lisbon Water Record as a Homeowner
Median and Range Insight
Lisbon’s treatment and sampling reflect a system-wide perspective. Your individual water quality may differ and should be assessed by a certified laboratory test to inform appropriate treatment decisions.
In summary, the Lisbon Water Department’s record covers public water system-wide measurements and treatment processes, serving thousands with groundwater. For households where existing equipment cannot keep pace with whole-home drinking water needs, reviewing certified laboratory test results, usage patterns, and treatment capacities is essential to selecting an appropriate solution like the C-Series Whole-Home + Drinking Combo System.
Source: EPA SDWIS public water system record for LISBON WATER DEPARTMENT (ME0090870)
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2025-12-31. These figures describe the public water system's record, not the plumbing inside any individual building.
On record: EPA SDWIS record for LISBON WATER DEPARTMENT (ME0090870), groundwater supply, serving 6643 people: 1 health-based violations of 12 total; lead 90th percentile 0.0016 mg/L