Local Aquifer 100TRNS and Water Movement to Household Taps
Water supplying homes in Orange County often comes from wells tapping the 100TRNS aquifer, where groundwater is drawn from depths between 31 and 42 feet. This water travels through underground rock and soil before reaching residential plumbing, which can influence taste and other water characteristics.
Understanding 'Detected', 'Median', and 'Range' in Regional Sampling
The US Geological Survey collected 48 samples from six wells in the area between mid-2011 and early 2013. In these results, iron was detected in 35 samples, with a median concentration of 9.9 micrograms per liter and a range from 3.6 up to 356 micrograms per liter. The term 'detected' means the instrument measured iron; it does not indicate a violation or unsafe condition. The median represents a middle value among the sampled results, while the range shows the lowest to highest measured values.
Interpreting Certified Laboratory Reports for Home Testing
For a specific household, a certified lab test can quantify iron concentration precisely. These reports should be reviewed for numerical values reported in micrograms per liter or similar units. Since area-wide sampling shows variation within the aquifer, individual well tests are essential to characterize household water. Interpreting these results helps determine if a technical treatment solution is appropriate.
Plumbing Materials and Age: A Separate Consideration
The taste perceived in household water is not solely dependent on source water quality. Plumbing materials—such as older pipes containing metallic components—can interact with water and contribute to a metallic taste. These effects are separate from the aquifer's composition and can vary from home to home.
Differences Between Public Water System Records and Private Well Testing
Public water suppliers routinely monitor water quality and maintain compliance records. In contrast, private wells are generally the responsibility of the homeowner to test independently. Orange County’s aquifer data are from government sampling, not direct readings from any individual's well or municipal system, so personal water tests remain critical for accurate assessment.
Fixtures and Appliances More Sensitive to Metallic Taste
Metallic taste issues often first appear in water outlets and appliances that use water directly for consumption or heating, like kitchen faucets, coffee makers, or ice machines. These points may highlight taste problems even if other household water uses are unaffected.
Summary: This briefing examined USGS sampling data from Orange County's 100TRNS aquifer and how to interpret median and range values for iron. It clarified that only specific lab tests reveal individual water quality and noted the important roles of plumbing and water use points in metallic taste. Considering these factors guides households in choosing between technical approaches, such as the Pentair Metallic-Tasting Water Filter, which ships ready to configure for this concern.
Where this information comes from
Source: USGS groundwater sampling. Sampled 2013-03-27. 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 100TRNS aquifer (Orange County): 48 results from 6 wells, median 9.9 ug/L, range 3.6-356.0 ug/L; none above any federal threshold