If you live in or near Folsom CA, you may have heard about an increase in pinhole copper leaks over the last few months. With over 1000 cases reported as of 10/16, these pinhole water leaks have become a cause for questions & concern with many homeowners in the Folsom area.

If your home is affected, or you suspect a possible leak, give our office a call at 916-933-6363 and our award winning team will assist you with scheduling inspections & repairs, as well as answer questions about what preventative measures are available.


Pinhole water leaks are typically a rare occurrence, which is why the frequency of these water leaks in Folsom are such a notable issue for homeowners, residents, plumbers and of course the City of Folsom. Pinhole leaks are caused by corrosion in copper pipes that slowly eats away at the pipe over time, causing pitting and eventually small pores or “pinholes”. If left untreated, these small, gradual leaks will begin to grow with devastating effects.

Due to the out-of-sight nature of plumbing in general, pinhole leaks are often difficult to detect, leaving homeowners with an abnormally high water bill as the only sign of an issue. As the leak continues to grow from a drip, it can saturate the surrounding insulation and/or drywall causing mold growth, swelling and other moisture related issues.


The City of Folsom is working with forensic experts from Virginia Tech University and engineering firm Black & Veatch to examine the copper pipes as well as the water composition.

The City of Folsom released the Water Quality Evaluation Report on 10/16/2020 [ available HERE ], which found that the low alkalinity and calcium content of the sourced water (prior to treatment) causes fluctuation in the pH levels when using free chlorine as a disinfectant. This combination of factors would indeed contribute to the onset of pitting in copper pipes. In short, the water pulled from the Folsom Reservoir is uniquely pure, therefor causing spikes in pH levels when treated. The report also suggests that replacing free chlorine with orthophosphates will prevent further damage.

For more information and resources, or to access the full report, please visit the City website at


This ongoing issue of pinhole copper leaks has become a cause for concern for many homeowners in the Folsom area, and rightfully so. Firstly, it is important to identify if your home has copper pipes. Homes plumbed with non-copper pipes (ie galvanized steel, PEX, Kitec etc) are not currently being affected. Unfortunately, a majority of homes in the Folsom area are plumbed with copper pipes.

If your home has copper plumbing, it is important to keep an eye out for signs of a leak, such as:

  • Abnormally high water usage, as indicated on your water bill
  • Water spots appearing on ceilings and/or walls
  • Swollen baseboards and/or flooring
  • Hissing or dripping sounds
  • Constant moisture or water pooling near exterior walls
map folsom water leaks

A updated map of neighborhoods reporting copper leaks can be found at

For more information or to report a leak, contact the City of Folsom Environmental and Water Resources Department at 916-461-6177 or