A laboratory test report for iron in household water typically provides a concentration value measured in micrograms per liter (ug/L). For residents in San Juan County drawing from aquifer 110AVMB, government groundwater sampling by the U.S. Geological Survey recorded iron concentrations in 112 samples from 8 wells between October 2021 and September 2025. The median iron level in these samples was 370.0 ug/L, with a range from 88.0 to 22,000.0 ug/L. Iron was detected in 100 of the samples; 12 were below the reporting limit. Importantly, none of the measured concentrations exceeded any federal health thresholds according to the official record.
If you are estimating treatment capacity against your household’s daily water demand
When considering treatment for iron bacteria, it is essential to gauge how much water you use daily. Household water demand varies widely but typically ranges from 50 to 100 gallons per person per day. The treatment system you select must handle your peak and average flow rates to effectively reduce iron bacteria and associated slime without restricting water availability. You should plan for a treatment technology that is capable of managing your full household water volume at typical pressure and flow conditions.
If you want to understand the effects of untreated iron bacteria over years
Iron bacteria in well water can lead to the formation of slime deposits inside pipes and plumbing fixtures. Over time, these deposits may cause staining on laundry and bathroom surfaces, increased maintenance needs for faucets and appliances, and reduced water flow due to clogged pipes or filters. However, these effects develop gradually and depend on iron concentration levels and water usage patterns. Leaving iron bacteria untreated does not pose a direct health risk under observed local conditions but can decrease water system efficiency and aesthetics.
If you consider how sample and well depths influence expectations
The iron data from San Juan County were collected from wells ranging 35 to 68 feet deep. Iron concentrations and the presence of iron bacteria can vary with well depth and aquifer characteristics. Shallower wells may show different profiles compared to deeper wells due to varying redox conditions and groundwater flow. Therefore, knowing your actual well depth is crucial, as it influences the likelihood and amount of iron bacteria present compared to the regional sampling data.
If you want to evaluate the confidence level from sample size and well count
The iron bacteria data come from 112 samples collected across 8 wells in this aquifer area. This is a substantial dataset that provides a reliable regional baseline but does not guarantee that your specific well falls within the same concentration range. Variability between individual wells can be significant, so while the data guide expectations, testing your water is the only way to know your exact iron bacteria levels.
If you wonder about plumbing materials and their role independent of the water source
Plumbing age and materials can affect how iron bacteria-related deposits accumulate in your home’s water lines. Older pipes made of iron or galvanized steel may encourage more slime buildup, while modern plastics tend to resist it better. This means that even with the same source water, the condition inside your household plumbing may differ noticeably based on these factors.
If you are a commercial or industrial operator considering additional factors
While this page focuses on residential water concerns, commercial or industrial users must consider treatment scale, regulatory compliance, and system redundancy more rigorously. They also may need to address iron bacteria impacts on manufacturing processes or equipment lifespan, requiring more complex evaluations beyond household needs.
To decide between treatment options effectively, the single most informative step is to have your well water tested specifically for iron and iron bacteria presence. A test report that quantifies these levels will enable a targeted approach. If iron bacteria are confirmed at levels where aesthetic or maintenance issues occur, solutions like the Pentair Iron Bacteria & Slime Filter system ship ready to configure and are designed to manage iron bacteria effectively for household demand, offering a practical path forward after testing confirms the need.
Where this information comes from
Source: USGS groundwater sampling. Sampled 2025-09-19. These figures describe groundwater sampled in this area. They are not a test of any individual private well - only a test of that well can establish its own water.
On record: U.S. Geological Survey sampling of Iron in the 110AVMB aquifer (San Juan County): 112 results from 8 wells, median 370.0 ug/L, range 88.0-22000.0 ug/L; none above any federal threshold