IVGID's drinking water found to have pH level above secondary drinking water standards

This notice is to let you know that IVGID’s water system recently exceeded a Secondary Drinking Water Standard. Although this is not an emergency, as our customers you have a right to know what happened, what you should do, and what we did and are doing to correct this situation.

IVGID routinely monitors for the presence of drinking water contaminants as required by the Nevada Division of Environmental Protection (NDEP). Testing results from samples taken between July 2024 and January 2025 indicate that pH levels were above the Secondary Maximum Contaminant Level (SMCL) guidelines of 6.5-8.5 pH. The average detected concentration was 8.7 pH.

What should I do?

You do not need to use an alternative water supply (e.g., bottled water) - pH level is an aesthetic constituent. However, if you have specific health concerns, consult your doctor.

What does this mean?

The pH levels in our drinking water is an aesthetic constituent, not a safety concern. Noticeable effects related to high pH levels above the SMCL in drinking water (above 10.0) can be a slippery feel, soda taste, and/or mineral deposits; however, it is unlikely that you will notice any difference at the 8.7 pH levels recorded during the testing period.

Secondary Drinking Water Standards (or secondary standards) are guidelines regulating contaminants that may cause cosmetic effects (such as skin or tooth discoloration) or aesthetic effects (such as taste, odor, or color) in drinking water. The U.S. EPA recommends secondary standards to water systems but does not require systems to comply with the standard. However, states like Nevada have chosen to adopt them as enforceable standards.

Background information

The pH of water can be thought of as a measure of acid-base equilibrium, which is impacted by many influential factors. The pH of raw Lake Tahoe water (the source for IVGID’s drinking water) can differ based on the time of day, season, depth of the water sample and more. Currently, the pH of the raw lake water here in Incline Village sits at around 8.0, whereas the pH of our treated water typically fluctuates between 8.5 to 8.8. There are a few different reasons why the pH of our water increases during the treatment process, for example the addition of residual chlorine into the system (required by NDEP) and corrosion control measures that protect IVGID’s distribution system.

There are even bottled water companies that market and sell high-pH water products, typically labeled as "alkaline water" or “high pH water.” You can find more information online about these products, which are regulated by the U.S. Food and Drug Administration, if you are interested.

What is IVGID doing?

Compliance Timeline: The Nevada Division of Environmental Protection (NDEP) requires yearly testing of multiple Secondary Drinking Water Standards including pH levels. Because our water exceeded this standard, IVGID is now required to provide pH testing quarterly for 2025. IVGID is following the guidelines set in place by the state regulatory agency, NDEP, and will continue to provide information to the public when necessary.

Action Plan:

  • IVGID will be performing the annual cleaning of the water intake screen at the water disinfection plant in early 2025, as required by NDEP. This maintenance could potentially help improve the pH issue.
  • IVGID will continue to continuously monitor both raw lake water pH and treated water pH 24 hours a day, 7 days a week.
  • IVGID will remain in compliance with NDEP regulations by continuing to conduct quarterly monitoring throughout 2025.

More information and resources about pH levels in drinking water

U.S. EPA resources: https://www.epa.gov/sdwa/drinking-water-regulations-and-contaminants

NDEP Water Controls Secondary Standards – General Requirements: https://www.leg.state.nv.us/nac/nac-445a.html#NAC445ASec455

For more information, please contact the IVGID Public Works office at 775-832-1203.

Please share this information with all the other people who drink this water, especially those who may not have received this notice directly (for example, people in apartments, nursing homes, schools, and businesses). You can do this by posting this notice in a public place or distributing copies by hand or mail.

 

This notice is from the Incline Village General Improvement District - State Water System ID#: NV0000158.

Date distributed: February 14, 2025