Key Water Quality Terms

Noted on the adjacent water quality table are definitions of key terms that refer to the standards and goals for water quality described below:

Public Health Goal (PHG): The level of a contaminant in drinking water below which there is no known or expected risk to health.The California Environmental Protection Agency sets the PHGs.

Maximum Contaminant Level Goal (MCLG): The level of a contaminant in drinking water below which there is no known or expected risk to health.The USEPA set the MCLGs.

Maximum Contaminant Level (MCL): The highest level of a contaminant that is allowed in drinking water. Primary MCLs are set as close to the PHGs or MCLGs as is economically and technologically feasible. Secondary MCLs are set to protect the odor, taste, and appearance of drinking water.

Maximum Residual Disinfectant Level (MRDL): The highest level of a disinfectant allowed in drinking water. There is convincing evidence that addition of a disinfectant is necessary for control of microbial contaminants.

Maximum Residual Disinfectant Level Goal (MRDLG): The level of a drinking water disinfectant below which there is no known or expected risk to health. MRDLGs do not reflect the benefits of the use of disinfectants to control microbial contaminants.

Primary Drinking Water Standard (PDWS): MCLs and MRDLs for contaminants that affect health along with their monitoring and reporting requirements, and water treatment requirements.

Treatment Technique (TT): A required process intended to reduce the level of a contaminant in drinking water.

Regulatory Action Level: The concentration of a contaminant which, if exceeded, triggers treatment or other requirements that a water system must follow.

Turbidity is a measure of the cloudiness of the water. We monitor it because it is a good indicator of water quality. High turbidity can hinder the effectiveness of disinfectants.

Cryptosporidium is a parasitic microbe found in most surface water.The SFPUC regularly tests for this water-borne pathogen and found it at very low levels in source water and treated water in 2014. However, current test methods approved by the USEPA do not distinguish between dead organisms and those capable of causing disease. Ingestion of Cryptosporidium may produce symptoms of nausea, abdominal cramps, diarrhea, and associated headaches. Cryptosporidium must be ingested to cause disease, and it may be spread through means other than drinking water.

Drinking Water Source Assessment

In March, 2003, a drinking water source assessment was completed. The assessment showed that five of Daly City’s six municipal production wells assessed as being highly protected from potential pathways of contamination. Well #4’s assessment showed it as being moderately protected. With the activation of the new Sullivan well in 2015, Well #4 has been designated as an emergency standby well. Daly City’s municipal wells are considered most vulnerable to automotive repair activities,roadway contaminants, and railways. A copy of the complete assessment is available from the State Water Resources Control Board, Division of Drinking Water, 850 Marina Bay Parkway, Building P, 2nd Floor, Richmond, CA 94804. You may also obtain a summary of the assessment by contacting either State Board District Engineer Eric Lacy at. (510) 620-3453, or Daly City’s Water and Wastewater Resources Department at (650) 991-8200.

Fluoridation Program. Mandated by State law, water fluoridation is a widely accepted practice proven safe and effective for preventing and controlling tooth decay. The SFPUC has fluoridated drinking water for more than 50 years. Since June 2004, Daly City fluoridates the blended well water supply throughout the entire community in keeping with the optimum level established by the SWRCB. Blended water, into your home, is optimally fluoridated at 0.7 mg/L. Average dosage for 2019 was ND-0.7. For additional information visit the SWRCB website:

www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/ Fluoridation.html.

Special Health Needs. Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that water poses a health risk. Some people may be more vulnerable to contaminants in drinking water than the general population. Immuno-compromised persons, such as those with cancer undergoing chemotherapy, persons who have undergone organ transplants, people with HIV/AIDS or other immune system disorders, some elderly people, and infants can be particularly at risk from infections. These people should seek advice about drinking water from their health care providers. USEPA/Centers for Disease Control guidelines on appropriate means to lessen the risk of infection by Cryptosporidium and other microbial contaminants are available from the Safe Drinking Water Hotline at 800-426-4791 or at www.epa.gov/safewater.

Water Conservation

Residents and businesses continued practicing the strong water conservation behavior they have demonstrated since June, 2015. Presently, imposition of individual mandated household targets is not anticipated. While Governor Brown’s Executive Order in April, 2017 ended California’s Drought Emergency, the State Water Resources Control Board continues to have agencies report conservation standards. Daly City residents are encouraged to continue to use water wisely, because it is impossible to predict whether drought conditions will return. Continued wise water uses aimed at avoiding unreasonable waste of water include:

The application of potable water to outdoor landscapes in

• a manner that eliminates runoff such that water flows onto adjacent property, non-irrigated areas, private and public walkways, roadways, parking lots, or structures.

The use of a hose that dispenses potable water to wash a motor vehicle, except where the hose is not fitted with a shut-off nozzle or device attached to it that causes it to cease dispensing water immediately when not in use.

Never using potable water to wash driveways and sidewalks. Use a broom instead.

Using a recirculation pumping system in a fountain or other decorative water feature.

Serving of drinking water by dining establishments, including but not limited to restaurants, hotels, cafes, cafeterias, bars, or other public places where food and drinks are served, is OK when first requested by a customer.

Common sense practices like these will enable us to continue to responsibly do our share in conserving precious water resources.

Free Water Conservation

Devices and Cash Rebates

To assist our customers in on-going conservation efforts, the Department of Water and Wastewater Resources offers a variety of free water saving devices, publications, rebates, and school programs for residents, commercial users, and students. For more information contact the Department of Water and Wastewater Resources at (650) 991-8200.

For additional water conservation information, visit: www.dalycity.org

Your water quality is

important.

If you have questions, or would

like more information ...

Contacts for Your Questions

We are here to serve the Daly City community ... if you require assistance:

To report leaks, service problems, or other water quality issues, please immediately contact the Department of Water and Wastewater Resources at (650) 991-8200.

For any questions regarding your water bill and/or to stop or start service, please contact Utility Billing at (650) 991-8082.

If you have questions regarding the Water Quality Report, would like additional technical or other information, or have any other water related questions or concerns, please call the Daly City Water and Wastewater Resources Department (650) 991-8200 ...

your question will be routed to the appropriate staff member for response.

If English is Not Your Primary Language

This report contains important information regarding your drinking water. Call the Daly CityWater andWastewater Resources Department (650) 991-8200 should you require assistance in Chinese, Spanish, or Tagalog.

Este reporte contiene información muy importante de su salud y el agua que toma. Llame a Daly City Water and Wastewater Resources Department a (650) 991-8200 si necesita asistencia en Español.

(650) 991-8200

Ang ulat na ito ay naglalaman ng mahalagang impormasyon tungkol sa inyong kalusugan at sa inumin ninyong tubig. Mangyari po lamang na tawagan ang Daly City Water and Wastewater Resources Department sa numero (650) 991-8200 kung kinakailangan ninyo ng tulong o interpretasyon sa wikangTagalog.

City of Daly City Department of Water and Wastewater Resources

153 Lake Merced Boulevard Daly City, CA 94015

(650) 991-8200

2020

Daly City Water Quality Report

To our water customers:

This 2020 Water Quality Report contains required regulatory information about

Daly City’s water supply compliance with State standards. It is your right to have and know this information, and to become an informed customer of your public water system. The City of Daly City is pleased to present this report to you.

2020 Daly City Water Quality Report

City of Daly City - Water Quality Data for 2020(1)

Data based on Hetch Hetchy water, and effluents from both SVWTP and HTWTP.

Water Quality Data

Your drinking water undergoes a rigorous monitoring program. Daly City staff vigilantly safeguards its water supplies and we are proud to report that your water once again meets or surpasses every drinking water requirement set by the State Water Resources Control Board (State Board), Division of Drinking Water and the United States Environmental Protection Agency (USEPA) drinking water health standards. This brochure is a snapshot of last year’s water quality. Included are details about where your water comes from, what it contains, and how it compares to state standards. We are committed to providing you with this information because we strongly believe in keeping our customers fully informed.

Drinking Water Sources

The sources of drinking water (both tap water and bottled water) include rivers, lakes, oceans, streams, ponds, reservoirs, springs, and wells. As water travels over the surface of the land or through the ground, it dissolves naturally occurring minerals and, in some cases, radioactive material, and can pick up substances resulting from the presence of animals or from human activity. Such substances are called contaminants. Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that water poses a health risk. To ensure that tap water is safe to drink, the USEPA and the State Board prescribe regulations that limit the number of certain contaminants in water provided by public water systems. The State Board regulations also establish limits for contaminants in bottled water, limits that provide the same protection for public health.You can obtain additional information about contaminants and potential health effects by calling the USEPA’s Safe Drinking

water to preserve the local water supply during years when there is more regional surface water available. In 2020, all of Daly City’s Drinking water came from the SFPUC surface water supplies. The Westside Basin serves a large portion of the northern San Mateo Peninsula and extends north to Golden Gate Park in San Francisco. It is worth noting that, in many ways, groundwater is a better protected source than surface water due to its closed environment. Thanks to consistent good water quality test results, our local well water is only required to have injected disinfection chemicals (rather than more extensive treatment) prior to being pumped into the drinking water distribution system.

Hetch Hetchy

Impounded in Yosemite National Park, Hetch Hetchy is supplemented with surface water from two local watersheds. Rainfall and runoff from the 35,000-acre Alameda Watershed in Alameda and Santa Clara counties are collected in the Calaveras and San Antonio reservoirs and delivered to the Sunol Valley Water Treatment Plant (SVWTP). Rainfall and runoff from the 23,000-acre Peninsula Watershed in San Mateo County are stored in the Crystal Springs, San Andreas, and Pilarcitos reservoirs, and delivered to the Harry Tracy Water Treatment Plant.

In addition to these local sources, the SFPUC received approval to use the surface water collected in Lake Eleanor, Lake Cherry, and the associated creeks ... all conveyed via the Lower Cherry Aqueduct, Early Intake Reservoir, and Tuolumne River (collectively known as Upcountry Non Hetch Hetchy Sources, or UNHHS) as additional drinking water sources; this water, if used, will be

The table to the left lists drinking water contaminants detected in 2020. Contaminants below federally established detection limits, such as arsenic, perchlorate, MTBE, and others, are not listed. The table contains the name of each contaminant, the applicable drinking water standards or regulatory action levels, the ideal goals for public health, the amount detected, the typical contaminant sources, and footnotes explaining the findings.The State allows the San Francisco Public Utilities

Commission (SFPUC) to monitor for some contaminants less than once per year because their concentrations do not change. For certain other contaminants that were absent in the water, based on many years of monitoring, the SFPUC received a monitoring waiver from the State.

Results for total Chromium at Daly City Wells are always below the SWRCB MCL of 50 ppb.While Nitrate levels in the Daly City system are maintained at safe levels, it is worth noting that Nitrate in drinking water at levels above 45 parts per million is a health risk for infants less than six months of age. Such

nitrate levels in drinking water can interfere with the capacity of the infant’s blood to carry oxygen, resulting in serious illness. Symptoms include shortness of breath and blueness of the skin. Nitrate levels above 45 parts per million may also affect the ability of the blood to carry oxygen for other individuals, such as pregnant women and those with certain specific enzyme deficiencies. If you are caring for an infant or are pregnant, you should seek advice from your health care provider.

Control Board to determine where certain contaminants occur and whether those contaminants need to be regulated. Daly City was required to monitor the 30 chemical contaminants and completed all the required monitoring for UCMR4. The 30 chemical contaminants included 10 cyanotoxins, 2 metals,

Contaminants that may be present

in source water include:

Microbial contaminants, such as viruses and bacteria that may come from sewage treatment plants, septic systems, agricultural livestock operations, and wildlife;

Inorganic contaminants, such as salts and metals that can be naturally occurring or result from urban storm water runoff, industrial or domestic wastewater discharges, oil and gas production, mining, or farming;

Pesticides and herbicides that may come from a variety of sources such as agriculture, urban storm water runoff, and residential uses;

Organic chemical contaminants, including synthetic and volatile organic chemicals, which are by-products of industrial processes and petroleum production, and can also come from gas stations, urban storm water runoff, agricultural application, and septic systems; and

Radioactive contaminants, which can be naturally occurring or be the result of oil and gas production and mining activities.

8 pesticides, 1 pesticide manufacturing byproduct, 3 brominated Haloacetic acid groups, 3 Alcohols, 3 semi volatile chemicals,TOC (indicator), and bromide (Indicator).

A list of the 30 contaminants is available at USEPA’s website:

https://www.epa.gov/dwucmr/fourth-unregulated-contaminant- monitoring-rule and at: http://www.swrcb.ca.gov.

Reducing Lead from

Plumbing Fixtures

Lead in drinking water, which has received national attention in Flint, Michigan, is primarily from materials and components associated with service lines and home plumbing. There are no known lead service lines in the Daly City water distribution system. In 2019 the City of Daly City participated in a triennial Lead and Copper Monitoring effort. The Department of Water and Wastewater Resources uses a predetermined list of residences approved by the State Division of Drinking Water, in which participating residences meet the criteria of being built after 1982. Sixty six samples were taken with 0 results reported above the action level. The overall result for Daly City’s 2019 Lead and Copper Monitoring event concluded that Daly City’s overall 90th percentile result was safely below the action level recommend by the EPA.

The City is responsible for providing high-quality drinking water (please see water quality footnote 10 in the adjacent

The Daly City water system has two sources of water supply: Hetch Hetchy surface water from the San Francisco Public Utilities Commission (SFPUC), and groundwater produced by local Daly City wells. These two sources are blended. SFPUC supplies approximately 60 percent of Daly City’s average daily demand. The remaining 40 percent of Daly City’s water supply comes from local groundwater wells, from an average depth of 300 feet below ground from a large underground aquifer known as the Westside Basin. Currently the City of Daly City is participating in “Conjunctive Use” of that resource. This effort aims to recharge the ground water basin by not using any ground

treated at the SVWTP prior to service to and any distribution. The Water at the two local treatment plants is subject to filtration, disinfection, fluoridation, and pH adjustment for corrosion control optimization.

How You Can Become Involved

Daly City welcomes your comments and suggestions on how to improve your municipal water system and better preserve our resources. Daly City holds City Council meetings beginning at 7:00 p.m. on the second and fourth Mondays of each month.These meetings are open to the public and are located on the second floor of City Hall, 333-90th Street in the Council Chambers. Important customer information is also available on Daly City’s website: www.dalycity.org.

10. The most recent Lead and Copper Rule monitoring was in 2019. 00 of 66 site samples collected at consumer taps had lead concentrations above the AL.
11. The detected chlorate in the treated water is a degradation product of sodium hypochlorite used by the SFRWS for water disinfection.

Additional water quality data may be obtained by calling the Daly City Department of Water and Wastewater Resources at (650) 991- 8200.

To ensure a safe drinking water supply, the fourth Unregulated Contaminant Monitoring Rule (UCMR 4) was published in the Federal Register on December 20, 2016. UCMR 4 required monitoring for 30 chemical contaminants between 2018 and 2020 using analytical methods developed by EPA

and consensus

o r g a n i z a t i o n s . This monitoring provides a basis for future actions to protect public health.

Unregulated contaminant monitoring helps USEPA and the State Water Resources

• Unregulated Contaminant Monitoring Rule (UCMR4) completed sample results will be updated completed sample results are available.

1. For definitions of these water quality terms, please see the contaminants listing above.
2. This MCL was established by CDPH. USEPA has a MCL of 100 ppb.
3. CDPH has proposed a MCL of 10 ppb for chromium-6.

Water Quality

Data table) but cannot control the variety of materials used in plumbing components. If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Infants and young children are typically more vulnerable to lead in drinking water than the general population. If you are concerned about lead levels in your water, you may wish to test your water with a home test kit. You can further minimize the potential for lead exposure in water that’s been sitting for several hours, by flushing your tap for 30 seconds to two minutes before using water for drinking or cooking. Additional information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the Safe Drinking Water Hotline at 800-426-4791, or at www.epa.gov/safewater/lead.