City Investigating Small Pinhole Leaks Found in Residential Copper Water Pipes

The City of Folsom Environmental and Water Resources Department is sampling water and inspecting sample copper pipes in response to multiple reports of small pinhole water leaks in residential copper pipes.

City engineers are examining potential causes, including quality and age of the pipe materials, installation methodology and workmanship, unexpected foreign debris in the copper pipe, mixed metals in the plumbing, and water composition. City staff welcome and appreciate any information and assistance from affected residents that could help determine the potential cause for the pinholes to develop in certain copper pipes and not in others.  

City engineers are not aware of any causal connection between the drinking water and the pinholes in the copper pipes. The city has not made any changes to its water treatment process and the water supply is continuously monitored. The city continues to deliver high quality drinking water as summarized in the 2019 annual Consumer Confidence Report.

Results of the water sampling and copper pipe inspections, as well as recommended preventive and remedial measures, will be shared once information is available. Stay informed at and subscribe to the City of Folsom’s weekly e-newsletter

For more information, contact the City’s Water Quality Division at 916-461-6190 or by email at