1. How Sample Depth and Well Source Affect Expectations
Government sampling of Pima County’s aquifer includes wells ranging from 37 to 687 feet deep. The depth and type of well influence water characteristics such as pH, a key factor in corrosivity. Deeper wells may show different pH readings than shallower ones due to geological layers. Understanding that these samples represent the area aquifer generally—not any individual home well—is critical before drawing conclusions about your own water.
2. Effects of Untreated Corrosive Water Over Several Years
Water that is acidic, meaning it has a pH lower than the typical range, can gradually cause corrosion in household plumbing and appliances. This corrosion wears down metal pipes and fixtures, leading to leaks and damage that reduce lifespan and performance. Corrosive water can also affect the taste and appearance of water but this is a separate consideration from health safety. Addressing corrosive water is about preserving your home’s water system over time.
3. Seasonal and Multi-Year Variability Reflected in Sampling Dates
Sampling in Pima County has been conducted over an eight-year span from January 2016 through February 2024. This timeline captures variations that may occur seasonally or over longer terms. Understanding that pH levels fluctuate within this period helps in recognizing natural changes rather than anomalies. Any equipment choice should consider this variability as consistent features rather than isolated test results.
4. Interpretations of the Measured pH Range Versus Federal Secondary Standard
Government samples found pH in Pima County aquifer wells ranging from 6.8 to 8.8 standard units. The EPA secondary standard for pH is 6.5 to 8.5, which relates to aesthetic qualities and pipe corrosion potential—not a health-based limit. Notably, none of the 81 samples fell below 6.5, indicating typical acidity concerns affecting corrosivity are generally low. However, local variation can still exist, so knowing your own water’s pH is important.
5. How to Read the pH Median and Range as a Homeowner
The median pH recorded was 7.4 standard units. This suggests that half of the sampled wells had pH above 7.4, and half below, within the overall range given. For a household owner, this means that acidic or corrosive water conditions, while possible within the lower end of the range, tend to be moderate in this area. This context can assist in weighing whether your home’s water might contribute to corrosion issues needing treatment.
6. First Fixtures and Appliances Affected by Corrosive Water
Corrosive water tends to impact metal plumbing components, water heaters, and appliances with metal parts first, as these materials are susceptible to gradual deterioration from acidity. Signs include unusual wear on fixtures, leaks, or metallic taste. Understanding which parts are vulnerable helps prioritize protective measures and supports equipment choice for mitigation.
Before selecting equipment to manage potential corrosive water, the definitive step is to have your household water tested for pH and other relevant parameters. A test result showing pH near or below the lower end of the EPA secondary standard range would confirm corrosivity and support considering technologies such as the C-Series Corrosive Water Damaging Pipes Filter. This system ships ready to configure and is designed specifically to address corrosive water’s impact on residential plumbing.
Where this information comes from
Source: USGS groundwater sampling. Sampled 2024-02-01. 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 pH in the aquifer (Pima County): 81 results from 37 wells, median 7.4 standard units, range 6.8-8.8 standard units; EPA secondary standard for pH is 6.5-8.5 (aesthetic/corrosivity, not health-based); 0 of 81 sampled results fell below 6.5