If You Want to Understand the Basis of pH Data in This Area
The U.S. Geological Survey collected groundwater samples in aquifer 112SUMS, Whatcom County, WA, between 2010 and 2018. Their data includes 23 pH results from eight wells, each ranging in depth from 18 to 40 feet. This relatively small sample size means the figures provide an overview of groundwater characteristics rather than a detailed picture of every household well.
When evaluating these results, remember that a limited number of wells and samples means local variation is expected. Your own water source may have different pH values, which only a specific test can confirm.
If You Plan to Read a Certified Laboratory Test Report for Your Water’s pH
A lab report for pH will show a numeric value, called standard units, that expresses acidity or alkalinity. The U.S. Environmental Protection Agency’s secondary standard for pH ranges from 6.5 to 8.5 standard units. Values below 6.5 indicate acidic water, but this is an aesthetic guideline related to taste and corrosivity rather than a health-based limit.
Your local area’s median pH from the USGS sampling is 6.2 standard units, with individual samples ranging from 5.6 to 7.3. Some of these results fall below the EPA aesthetic range, indicating acidic water is common in several wells, but this does not define a violation or unsafe condition.
If You Wonder How Your Area’s pH Data Compares with Neighboring Counties
While this page focuses on Whatcom County’s aquifer 112SUMS, neighboring areas may show somewhat different pH ranges due to geology and groundwater chemistry. Comparing these records helps set expectations but should not lead to assumptions about your own water. Each county’s or aquifer’s sampling reflects separate geological and chemical contexts.
Differences in sample sizes, well depths, and collection methods can affect results. The presence of acidic water in one aquifer does not guarantee the same for another. Local testing is the only way to know your household water’s pH precisely.
If You Want to Know How Low pH Water Occurs in This Groundwater Source
Acidity in groundwater here typically results from natural processes, including the geological makeup of aquifer materials and organic matter decomposition. Acidic conditions can develop when carbon dioxide dissolves into water, forming weak carbonic acid, which lowers pH. These natural variations affect water chemistry and can influence household plumbing and water taste.
The record from Whatcom County wells supports this understanding, showing acidic pH values in multiple samples without indicating contamination or health hazards.
If You Are Concerned About Long-Term Effects of Untreated Acidic Water
Water with pH below the EPA secondary range may cause mild aesthetic and material effects over time. Some household plumbing materials and fixtures can corrode more quickly, leading to discoloration or metal taste. Appliances using water can also experience increased wear.
Such effects do not pose known health risks but can impact water appearance, taste, and plumbing longevity. Monitoring your water’s pH and addressing acidic levels may prevent these issues.
To determine if your household water requires treatment, the key step is to order a certified laboratory pH test from your well or water source. Results showing a pH below 6.5 standard units would indicate acidic water for your household specifically.
For managing acidic water identified by testing, consider the Autotrol Acidic / Low-pH Water Filter, a system that ships ready to configure for household use to help adjust water pH toward neutral.
Where this information comes from
Source: USGS groundwater sampling. Sampled 2018-08-08. 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 112SUMS aquifer (Whatcom County): 23 results from 8 wells, median 6.2 standard units, range 5.6-7.3 standard units; EPA secondary standard for pH is 6.5-8.5 (aesthetic/corrosivity, not health-based); 13 of 23 sampled results fell below 6.5