Copper Pipe Pinhole Water Leaks

City of Folsom Water Quality Division 
916-461-6190
waterquality@folsom.ca.us

The City of Folsom Environmental and Water Resources Department has received multiple reports of pinhole water leaks in Folsom residential and commercial buildings. The City of Folsom is committed to keeping the public informed about the status of the copper pipe pinhole water leaks, and actions taken to prevent and significantly slow pinhole leaks from occurring. This webpage is updated as new information is available. 


If you would like to report a pinhole leak, please fill out the pinhole leak survey. For questions or additional information, contact the City of Folsom Water Quality Division at 916-461-6190 or waterquality@folsom.ca.us

 

 

Timeline of Pinhole Leaks in Folsom - 


Permit Fees Waived for Pinhole Leak Repairs - November 4, 2020

On November 10, the Folsom City Council authorized a waiver of permit and inspection fees for any repairs related to pinhole copper pipe leaks. Residents who already incurred fees will be refunded, and a notification letter to affected residents was mailed this week. For information about pinhole leak permit and inspection fee refunds, call 916-461-6162 or email waterquality@folsom.ca.us. Learn more at www.folsom.ca.us/pinholeleaks.  


Copper Pipe Pinhole Water Leak Investigation Update, October 20, 2020

The City of Folsom received the final pinhole leak Water Quality Evaluation Technical Memorandum from consultant Black & Veatch. The city hired Black and Veatch, a consultant with expertise in water quality and corrosion, to work with specialists at Virginia Tech University to conduct detailed forensic analysis on sample copper pipes with pinhole leaks. The analysis indicates the city meets all State and Federal drinking water standards, including the United States Environmental Protection Agency’s (US EPA) Lead and Copper Rule. There is no evidence of microbial activity in the city’s water supply.

As described in the technical memorandum, the city’s treated water is low in alkalinity, calcium, total organic carbon, turbidity, and total dissolved solids. These characteristics are ideal in drinking water. However, the water’s purity combined with a pH above 9.0 and the use of chlorine could contribute to pitting of copper pipe, especially at sites with impurities in the pipe material or where particulate has settled. Impurities in copper pipe can be natural or from manufacturing, storage, transportation, or installation.

The team at Black & Veatch and Virginia Tech University recommended the city begin adding orthophosphate to the city’s treatment process. Orthophosphate is a commonly used corrosion inhibitor recommended by the US EPA for use in drinking water applications and is deemed safe for drinking water systems by the United States Food and Drug Administration. The addition of orthophosphate forms a protective layer on the interior of the copper pipe. This has shown to inhibit pit initiation and can help slow or even mitigate pit propagation. Based on an earlier verbal discussion with the consultant team, the city began adding orthophosphate to its treatment process on October 8, 2020, prior to the completion of the report.

Contact the City of Folsom Water Quality Division at 916-461-6190 or waterquality@folsom.ca.us with questions or for more information.


Copper Pipe Pinhole Water Leak Investigation Update, October 16, 2020

The City has received the final Water Quality Evaluation Technical Memorandum from consultant Black & Veatch related to pinhole leaks in Folsom. As promised, we are immediately posting that report and it can be found here. More information will be provided first thing next week as we complete our review and analysis.

Folsom Water Quality Evaluation Report


Copper Pipe Pinhole Water Leak Investigation Update, September 18, 2020

The City of Folsom Environmental and Water Resources Department has received multiple reports of small pinhole water leaks in local residential and business copper pipes.

The City of Folsom hired a consultant with expertise in water quality and corrosion to work with specialists at Virginia Tech University to conduct detailed forensic analysis on sample copper pipes with pinhole leaks. In addition to the forensics analysis, Black and Veatch is conducting a detailed water quality evaluation to determine if there are any trends in parameters related to corrosion.

On September 18, the City received a verbal report from Black and Veatch and Virginia Tech University about their analysis to date of copper pinhole leaks.

Due to COVID-19 related delays for access to the lab equipment, not all of the lab tests have been completed. A formal written report will likely not be available to the City until the first week of October. While a formal written report is not available at this time, the consultant team provided some initial feedback to the City based on their analysis completed to date. The consultant team stated the City’s water meets the requirements of its water operating permit issued by the State Water Resources Control Board’s Division of Drinking Water and that the water is safe for public consumption.

Absent the written report and with the understanding that this is a critical topic to address, the consultant team recommends that the City add orthophosphate to its treatment process and reduce the target pH leaving the water treatment plant. Orthophosphate is an acceptable corrosion inhibitor in the treatment process and is an approved chemical by the United States Environmental Protection Agency for use in public drinking water systems. The consultant believes that the use of orthophosphate could provide a coating to the inside of the copper pipe to reduce the possibility of pinhole formation. Understanding that this is an important issue for many, the City will proceed with the installation of an orthophosphate system as quickly as possible and will continue to monitor the situation.

During this time, Virginia Tech will complete the remaining pipe scale analysis that was delayed due to COVID-19 and access to the lab.  The City will share the written report as soon as it becomes available.  The City is also waiting for results from engineering firm HDR, another third-party water quality and corrosion consultant, and will share the report as soon as it becomes available as well. 

For more information or to report a leak, contact the City of Folsom Environmental and Water Resources Department at 916-461-6177 or waterquality@folsom.ca.us. Read answers to frequently asked questions: www.folsom.ca.us/pinholeleaks.

Stay informed at www.folsom.ca.us and subscribe to the City of Folsom’s weekly e-newsletter.   


Pinhole Leak Q&A 

Why the apparent increase in pH after about 2016-2017?
 
Answer – The variability in finished water pH is partially due to the low alkalinity and limited buffering capacity in the City’s natural water supply, combined with the approved water treatment process that meets drinking water standards. In the City’s 2016 water treatment plant permit amendment approved by the Division of Drinking Water, the City calculates pH based on the Langelier Saturation Index (LSI), which is a corrosion indicator used to adjust finished water quality parameters. Due to the purity of the raw water, the City typically operates with a negative LSI in the range of -1.4 to -1.7 after adding lime to adjust the pH, alkalinity, and calcium levels. The careful monitoring and adjustment of the lime dose, and thus the pH, help keep the LSI from decreasing further. By trying to maintain a less negative LSI to improve finished water quality, pH values increase.

Why is the pH so high in Folsom? Is it the same as other water districts that source their water from Folsom Lake, like San Juan Water District (SJWD) and Roseville?
Answer – The average pH level in the City’s treated water is not unusually high and is similar with other water agencies, including SJWD and Roseville.

Does anyone know what was specifically changed in the water supply recently? Does anyone know why our pH is at 9?
Answer – There were not changes in the water supply. The consultant team believes the more likely explanation for pH in the City’s system is that the pH reading at the entry point is too close to the lime feed point where the water is still reacting to the chemical addition due to the low buffering capacity. In some distribution system reservoirs, residual lime can settle out, which could increase the pH within the distribution system.

Would a lower pH have prevented pinhole leaks?
Answer – According to the consultant team, if pH had consistently been controlled around 8.5, in all likelihood pitting would still have occurred eventually (especially with impurities and particulates in the pipes), but possibly at a later date and a lower frequency of leaks.

Is there an optimal pH target?
Answer: The optimal pH levels vary from system to system and depends on a variety of water quality parameters in the raw water and finished water. The secondary maximum contaminant level, which is a non-regulatory guideline addressing contaminants that may cause cosmetic effects or aesthetic effects in drinking water, provided a pH range of 6.5-8.5.

Who determines what the pH should be?
Answer: The process in determining the pH is described in the City’s water treatment plant operating permit, which is approved by the Division of Drinking Water. See number 1 above for the pH indicator.

Are we required to add chlorine to the water?
Answer – Yes. Under the Safe Drinking Water Act, the City is required to add chlorine disinfection to its treatment process with a residual no less than 0.50 parts per million (ppm) and no higher than 4.0 ppm in the water distribution system.

Are we adding too much chlorine to the water?
Answer – No. The Environmental Protection Agency allows a minimum of 0.5 ppm and a maximum of 4.0 ppm of chlorine residual in drinking water supplies. The city maintains an average of 1.1 ppm in its drinking water.

Will a whole house filtration system filter out orthophosphate the City is adding to coat the interior of the copper pipes?
Answer – According to the consultant team, certain whole house filtration systems using activated carbon as a filtering material can reduce phosphate in the water by 70-90 percent. The City recommends that if homeowners are planning to install a whole house filtration system, the homeowner should consult with the filtration system manufacturer to verify that the system does not filter out phosphates. If the filtration system filters out phosphates, this could hinder the ability of orthophosphate to limit pitting corrosion.   

Does the City use chloramines in their water system?
Answer – The City does not use chloramines in the water treatment process. The City uses sodium hypochlorite, which is an industry-accepted standard disinfectant to provide for safe and healthy drinking water.

Has the City made any changes to the treatment process recently, in the last 5 years?
Answer – The City has not made any changes to its treatment process or to the type of disinfectant chemicals used in the treatment process in the last 5 years.

How long has the City used its current disinfectant, sodium hypochlorite?
Answer –The City follows accepted industry practices for treating water for public consumption and has used sodium hypochlorite for about 20 years.

Does the City’s water have a low pH?
Answer – Any solution with a pH level below 7 is acidic, and the City’s water system pH being in the 7.7-8.2 range means that the City’s water is not acidic.

Does the City have hard water?
Answer – The City water hardness, which ranges from 17-33 within the system, is considered slightly hard based on the following range:

  • 0-17.1: Soft
  • 17.1-60: Slightly Hard
  • 60-120: Moderately Hard
  • 120-180: Hard
  • Over 180: Very Hard

How does the City’s treatment process and use of chemicals compare to neighboring water agencies?
Answer – While not all water agencies use exactly the same treatment process, the City’s treatment process and the chemicals used for pre-treatment, disinfection, and corrosion control are similar to the City’s neighboring water agencies (City of Roseville, City of Sacramento, San Juan Water District, and El Dorado Irrigation District). In many cases, the City uses the same chemicals as the other water agencies.

Does the City add any chemicals to prevent corrosion?
Answer: Like neighboring water agencies, the City uses lime for pH adjustment and corrosion control purposes.  The amount used is consistent with accepted industry-practices for treating drinking water.

Is the City’s water safe to drink?
Answer – The City’s water is safe to drink and meets or exceeds all State and Federal regulations.

What is the City doing?
Answer - The City hired a consultant with expertise in water quality and corrosion to work with specialists at Virginia Tech University to conduct detailed forensic analysis on sample copper pipes with pinhole leaks. In addition, to the forensics analysis, Black and Veatch will conduct a detailed water quality evaluation to determine if there are any trends in parameters related to corrosion

Who can we contact about a pinhole leak?
Answer - Customers with questions or pinholes leaks can call the City’s Water Quality Division at 916-461-6190 or email waterquality@folsom.ca.us.

Has the City made any changes to the water pressure?
Answer – The City has not made any operational changes within the last 10 years to the water pressure in the system. The City is required to deliver at all times, at a minimum, 20 pounds per square inch (psi) of operating pressure to the City’s water customers. The California Plumbing Code requires a pressure regulator to be installed when static operating pressures exceed 80 psi.

Does the City have to report these pinhole leaks to the State Water Resources Control Board?
Answer – The City does not have to report these pinhole leaks to the State Water Resources Control Board (SWRCB). Although not required, the City did inform the SWRCB – Division of Drinking Water of the occurrence of pinhole leaks within the City’s water system. City staff and SWRCB staff will meet at the end of September to discuss the pinhole leaks.

Did the City make any changes to the water pressure of the system?
Answer – The City has not made any changes to the City’s water pressure.

Do all the leaks occur on cold water pipes?
Answer – No. A majority of the leaks occur on the cold water pipes, but some have occurred in the hot water pipes. 

Does the City perform laboratory test for heavy metals?
Answer – Yes. On a quarterly basis, the City tests for the following metals: calcium, copper, iron, magnesium, manganese, potassium, silver, sodium, and zinc.

Where do residents in American River Canyon get their water supply?
Answer: San Juan Water District is the water provider for residents and businesses in the American River Canyon neighborhoods.

What is the source of the City’s drinking water?
Answer – The source of the City’s drinking water supply is Folsom Reservoir. 

Will the City make the findings of the analysis available to the public? 
Answer – Yes. The City will make the findings available to the public. For a copy of the lab results provided to Black & Veatch, please email waterquality@folsom.ca.us.

Will the study provide any recommendations? 
Answer – The two studies will include recommendations and/or corrective measures the City should consider implementing.  

For City of Folsom water quality lab results dating back to 2010, contact waterquality@folsom.ca.us.