City of Santa Clara I 2025 Public Health Goals Report
2025 Report on Water
Quality Relative to Public
Health Goals (2025 Public
Health Goals Report)
City of Santa Clara Water and Sewer Utilities
for Compliance with California Health and Safety Code Section 116470(b)
City of Santa Clara II 2025 Public Health Goals Report
TABLE OF CONTENTS
1. BACKGROUND ................................................................................................................ 3 MCLs, PHGs, and MCLGs Defined: ................................................................................................... 4 City of Santa Clara’s Water Quality Data: ........................................................................................ 5
2. CONSTITUENTS DETECTED THAT EXCEED A PHG OR MCLG: ....................... 5 Arsenic 5
Hexavalent Chromium ..................................................................................................................... 7 Perchlorate ....................................................................................................................................... 8 Recommendations for Further Actions: .......................................................................................... 9 ATTACHMENT 1 ......................................................................................................................... 10 MCLs, DLRs, and PHGs ................................................................................................................... 10 ATTACHMENT 2 ......................................................................................................................... 11 California Health and Safety Code ................................................................................................. 11 ATTACHMENT 3 ......................................................................................................................... 12 City of Santa Clara Consumer Confidence Reports ........................................................................ 12
City of Santa Clara 3 2025 Public Health Goals Report
1. BACKGROUND
The California Health and Safety Code Section 116470(b) specifies that water utilities serving more than 10,000 connections prepare a brief written report every three years that documents detections of any constituents that exceed a Public Health Goal (PHG) in the preceding three years. PHGs are non-enforceable goals established by the California Environmental Protection Agency’s Office of Environmental Health Hazard Assessment (OEHHA). The law also requires that where OEHHA has not adopted a PHG for a constituent, the water suppliers are to use the Maximum Cont aminant Level Goal s (MCLGs) adopted by the United States Environmental Protection Agency (USEPA). Only constituents that have both a California primary drinking water standard and a PHG or MCLG as of December 31, 2024, are to be addressed in the report.
The City of Santa Clara last completed its PHG Report in 2022. PHGs are established goals by the OEHHA to protect public health. When OEHHA has not adopted a PHG for a particular constituent, the Safe Drinking Water Act directs water suppliers to use the MCLGs previously adopted by the USEPA, if available. PHGs and MCLGs are non- enforceable goals.
This 2025 PHG Report addresses constituents that:
• H
ave a California primary drinking water standard, or Maximum Contaminant Level (MCL), and
• For which either a PHG or MCLG has been established and exceeded in Santa Clara’s water quality monitoring data.
P
ursuant to the Safe Drinking Water Act, this report lists all constituents detected in the City's water supply from 2022 through 2024 at levels exceeding an applicable PHG or MCLG. The following are included:
• T
he numerical public health risk associated with the MCL and PHG or MCLG • The category or type of risk to health that could be associated with each constituent,
• The best treatment technology available that could be used to reduce the constituent level, and
• An estimate of the cost to install that treatment if it is appropriate and feasible T
he Association of California Water Agencies (ACWA) formed a workgroup that prepared a guidance for water utilities to prepare required PHG reports. The 2025 ACWA guidance was used in the preparation of this report. No guidance was available from state regulatory agencies.
City of Santa Clara 4 2025 Public Health Goals Report
MCLs, PHGs, MCLGs, and DLRs Defined:
The USEPA and the State Water Resour ces Control Board (SWRCB) establish MCLs at very conservative levels to prov ide protection to consum ers against all risks, excluding those of very low to negligible risk. In other words, MCLs are the regulatory definition of what is “safe” for drinking water.
MCLs are legal limits for substances in drinking water. They are set by the U.S. Environmental Protection Agency (EPA) and the State Water Resourc es Control Board (SWRCB). These limits are designed to protect people from all but very tiny risks while still being practical for water systems to meet.
There are also “health-based goals” called PHGs and MCLGs. PHGs are set by the California Office of Environmental Health Hazard Assessment (OEHHA), and MCLGs are set by the USEPA. These goals describe the level of a substance in drinking water where scientists expect no health effects, even over a lifetime. Determining health risks at these low levels is often theoretical, not poss ible in real-world conditions , and based on multiple assumptions.
Because PHGs and MCLGs are bas ed only on theoretical health risk, they are often set much lower than MCLs. Sometimes PHGs and MCLGs are set so low that today’s testing equipment cannot even measure them, or they may be set at zer o, which is not possible to reach in real-world conditions.
DLRs stands for detection limits for the purposes of reporting and are s et by the SWRCB. They are the minimum level a substance can be detected in drink ing water.
Based on the current laboratory technology available now, it would not be possible to detect substances below the DLR. Meeting DLRs means that SWRCB can be the confident about the accuracy of the substances’ quantity reported by the analytical lab. The DLR is typically set equal to or below MCLs but is often above the contaminant public health goal (PHGs). Currently, 92 existing MCLs have 49 DLRs set above their corresponding PHGs.
Unlike MCLs, PHGs and MCLGs are not enforceable by law. They do not take into account practical factors s uch as how easily a substance can be detec ted, what treatment methods exist, or how muc h those treatments cost. MCLs, on the other hand, balance health protection with what is technically and financially achievable for water systems.
City of Santa Clara’s Water Quality Data:
The City of Santa Clara’s Water Utility collected water quality data from 2022 through 2024 to check compliance with state and federal drinking water standards . These results were used in preparing this report.
We also share this information every year in our Consumer Confidence Report (CCR).
The CCR is mailed in June to all customers who receive a utility bill. It sum marizes water quality data collected from January through December of the previous year and is printed as a newspaper-style publication for easy reading.
City of Santa Clara 5 2025 Public Health Goals Report
Best Available Treatment (BAT) Technology and Cost Estimates:
Both the USEPA and SWRCB identify Best Available Technologies (BATs). These are the most effective methods for reducing contaminants in drinking water, so they meet the legal standards, called Maximum Contaminant Levels (MCLs).
However, no agency has developed BATs that can reliably remove substances to the extremely low levels set by PHGs or MCLGs. In many cases, technology to reach those goals does not exist.
Estimating the cost of treatment at such very low levels is also highly uncertain. Any figures would be mostly theoretical and may not justify spending significant public funds or staff time. In addition, trying to further reduce one substance to extremely low amounts could unintentionally affect other parts of water quality.
2. CONSTITUENTS DETECTED THAT EXCEED
A PHG OR MCLG:
The City detected arsenic, hexavalent chromium, and perchlorate in the distribution system, or source water for the distribution system, at levels above the applicable PHG or MCLG. This report includes any PHG or MCLG that was exceeded in one or more of our drinking water sources.
Arsenic
Arsenic is a substance that occurs naturally in rocks and soil, but it can also get into water from industrial runoff. It is considered a carcinogen (a substance that can increase the risk of cancer).
The PHG for arsenic, set by the OEHHA, is 0.004 parts per billion (ppb). This level is so low that today’s testing equipment cannot detect it. The current detection limit is at or above 2.0 ppb.
The MCL, which is the enforceable standard set by the USEPA and the SWRCB, is 10.0 ppb. Drinking water at the PHG level for a lifetime is estimated to carry a cancer risk of about 1 in 1,000,000, while drinking water at the arsenic MCL level carries an estimated risk of about 2.5 in 1,000 (or 5 in 2,000).
All the City of Santa Clara’s water sources meet the arsenic MCL, meaning our water complies with state and federal safety standards, and there are no harmful effects to residents.
City of Santa Clara 6 2025 Public Health Goals Report
Table 1: Summary of Arsenic Detected
2022 to 2024 Arsenic Results
Range of Results (ppb) MCL (ppb) PHG (ppb)
ND – 2.2 10 0.004
There are several treatment methods that can help remove arsenic from drinking water.
The most common options include blending, granular ferric oxide (GFO) adsorption, coagulation and filtration, ion exchange, and reverse osmosis (RO).
To look at potential costs, this report used RO as an example, based on cost estimates in dollars per 1,000 gallons treated (($/1,000 gal. treated) from ACWA guidance. RO is often chosen because it is also identified as the Best Available Technology (BAT) for several other inorganic chemicals, meaning it can treat more than one substance at the same time.
Reverse osmosis is a highly effective and widely used treatment method for both drinking water and wastewater. It works by pushing water through a special membrane under high pressure. The membrane lets water molecules pass through but holds back other substances. This process produces two streams: clean treated water and a smaller amount of concentrated wastewater that contains the removed contaminants.
Table 2: Summary of Arsenic Treatment Cost
Arsenic Treatment Cost
Price ($/1,000 gallons treated) * Total Estimated
Cost ($ in Millions)
Risk From No
Treatment
$2.46 - $8.99 $8.5 to $31.2 No Risk
*2025 ACWA Guidance
Using RO to remove arsenic also produces wastewater and byproducts that must be handled safely, which adds to the overall cost. Even though RO is considered the BAT for meeting the legal limit MCL, it may not be able to reach the much lower PHG for arsenic.
Another challenge is that today’s laboratory methods cannot measure arsenic at concentrations as tiny as the PHG. This means that, even if treatment could reduce levels that far, there would be no way to confirm that the PHG had been met.
Costs would also increase because each of the City’s 20 groundwater wells would need its own treatment unit. Installing and maintaining many small units is usually more expensive than using one large unit at a central location.
Because Santa Clara’s drinking water already meets both state and federal standards for arsenic, there are currently no plans to install additional treatment systems. Results
City of Santa Clara 7 2025 Public Health Goals Report
for arsenic are provided in the water quality tables published in the City’s 2022, 2023, and 2024 CCRs as documentation of compliance with the Safe Drinking Water Act.
Hexavalent Chromium
Hexavalent chromium can enter drinking water when it leaches from natural deposits in rocks and soil. Because it may increase the risk of cancer, OEHHA set a PHG for hexavalent chromium at 0.02 parts per billion (ppb). At that level, the estimated lifetime cancer risk is about one in one million.
The enforceable MCL standard was set by the SWRCB on October 1, 2024, at 10 ppb.
Drinking water at the MCL level carries a slightly higher estimated lifetime cancer risk of about five in ten thousand.
The PHG is far below today’s laboratory detection limit of 0.1 ppb, which means it cannot currently be measured. All of Santa Clara’s water sources meet the state MCL for hexavalent chromium and are in compliance with drinking water standards, and there are no harmful effects to residents.
Table 3: Summary of Hexavalent Chromium Detected
2022 to 2024 Hexavalent Chromium
Range of Results (ppb) MCL (ppb) PHG (ppb)
ND – 4.3 10 0.02
The identified BAT methods to remove hexavalent chromium from drinking water, have been identified by experts. The main method is the reduction, coagulation, and filtration treatment process. This treatment technology has been tested and shown to lower hexavalent chromium to about 1 ppb or less.
Cost estimates for the reduction, coagulation, and filtration treatment process come from the 2025 ACWA guidelines, which provide typical costs per 1,000 gallons of water treated.
Table 4: Summary of Hexavalent Chromium Treatment Cost
Hexavalent Chromium Treatment Cost
Price ($/1,000 gallons treated)* Total Estimated
Cost ($ in Millions)
Risk From No
Treatment
$2.14 - $13.38 $7.4 to $46.5 No Risk
*2025 ACWA Guidance
City of Santa Clara 8 2025 Public Health Goals Report
While the reduction, coagulation, and filtration treatment process can remove hexavalent chromium from drinking water, it comes with several challenges. This process creates toxic byproducts that must be handled and disposed of safely, which increases operating costs.
Even though this method can greatly lower hexavalent chromium levels, it cannot meet the very low PHG of 0.02 ppb. Current laboratory technology also cannot measure such tiny amounts, making it impossible to confirm PHG compliance.
Because Santa Clara’s water already meets both state and federal standards for hexavalent chromium, the City has no plans to install additional treatment. Test results are included in the water quality tables published in the City’s 2022, 2023, and 2024 CCRs as proof of compliance with the Safe Drinking Water Act.
Perchlorate
Perchlorate can get into water from certain industrial activities, such as making rocket fuel, propellants, and explosives. Some of this contamination comes from historical aerospace or similar operations.
The PHG for perchlorate, set by OEHHA, is 1 ppb. This goal is based on perchlorate’s ability to interfere with normal thyroid function, which helps regulate hormones.
Disruption of thyroid activity can affect growth and brain development, especially in fetuses and infants.
The enforceable MCL standard is 6 ppb. All of Santa Clara’s water sources are well below this limit and fully comply with state and federal standards for perchlorate, and there are no harmful effects to residents.
Table 5: Summary of Perchlorate Detected
2022 to 2024 Perchlorate Results
Range of Results (ppb) MCL (ppb) PHG (ppb)
ND – 1.1 6 1
The identified BAT methods for removing Perchlorate from drinking water include ion exchange (IX) and fluidized bed reactors (FBR). Ion exchange is one of the most used and cost-effective methods for perchlorate removal, shown in Table 6.
City of Santa Clara 9 2025 Public Health Goals Report
Table 6: Summary of Perchlorate Treatment Cost
Perchlorate Treatment Cost
Price ($/1,000 gallons treated)* Total Estimated Cost
($ in Millions)
Risk From No
Treatment
$0.67 - $1.47 $2.3 to $5.1 No Risk
*2025 ACWA Guidance
Ion exchange is an effective way to lower perchlorate levels in drinking water. However, this process creates waste that must be handled and disposed of according to environmental regulations, which adds extra steps and cost to treatment. Over time, the resin used in ion exchange can lose efficiency, meaning it may not always reduce perchlorate to the very low PHG of 1 ppb.
Because Santa Clara’s water already meets both state and federal standards for perchlorate, the City has no plans to install additional treatment. Test results for perchlorate are shown in the water quality tables in the City’s 2024 CCR as proof of compliance with the Safe Drinking Water Act.
Please note: the state’s Detection Limit for Reporting (DLR) for perchlorate changed from 2 ppb to 1 ppb on January 1, 2024. For this reason, perchlorate detections were not listed in the 2022 or 2023 CCRs, but they are included in the 2024 report.
Recommendations for Further Actions:
The City of Santa Clara’s drinking water meets all state and federal standards set by the SWRCB and the USEPA. These standards are designed to protect public health.
Reducing the levels of the substances identified in this report even further below what the state already considers “safe drinking water” would require very expensive treatment systems. In many cases, the technology may not be able to reach the extremely low levels set by PHGs or MCLGs or even confirm that those levels had been achieved.
The cost of installing and operating these treatments would be passed on to customers, with little or no additional health benefit. The water is well within the limits that ensure it is safe to drink, and further reductions would provide only minimal, if any, measurable improvement.
Because of these factors, the City is not proposing any new treatment at this time.
Santa Clara will continue to monitor water quality and ensure that all drinking water standards set to protect public health are consistently met.
City of Santa Clara 10 2025 Public Health Goals Report
ATTACHMENT 1
MCLs, DLRs, and PHGs
Table 7: Summary of Arsenic
Constituent MCL DLR PHG
Arsenic 10 ppb 2 ppb 0.004 ppb
Table 8: Summary of Hexavalent Chromium
Constituent MCL DLR PHG
Hexavalent
Chromium 10 ppb 0.1 ppb 0.02 ppb
Table 9: Summary of Perchlorate
Constituent MCL DLR PHG
Perchlorate 6 ppb 1 ppb 1 ppb
MCL = Maximum Contaminant Level
DLR = Detection Limit for the Purpose of Reporting
PHG = Public Health Goal
ppb = parts per billion
Source: California State Water Resources Control Board: Comparison of MCLs and PHGs for Regulated Contaminants in Drinking Water
https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/MCLsandPHGs.ht ml
Last Update: August 20, 2024
City of Santa Clara 11 2025 Public Health Goals Report
ATTACHMENT 2
California Health and Safety Code
Section §116470. Public Health Goal Report
(b) On or before July 1, 1998, and every three years thereafter, public water systems serving more than 10,000 service connections that detect one or more contaminants in drinking water that exceed the applicable public health goal, shall prepare a brief written report in plain language that does all of the following:
(1) Identifies each contaminant detected in drinking water that exceeds the applicable public health goal.
(2) Discloses the numerical public health risk, determined by the office, associated with the maximum contaminant level for each contaminant identified in paragraph (1) and the numerical public health risk determined by the office associated with the public health goal for that contaminant.
(3) Identifies the category of risk to public health, including, but not limited to, carcinogenic, mutagenic, teratogenic, and acute toxicity, associated with exposure to the contaminant in drinking water, and includes a brief plainly worded description of these terms.
(4) Describes the best available technology, if any is then available on a commercial basis, to remove the contaminant or reduce the concentration of the contaminant.
The public water system may, solely at its own discretion, briefly describe actions that have been taken on its own, or by other entities, to prevent the introduction of the contaminant into drinking water supplies.
(5) Estimates the aggregate cost and the cost per customer of utilizing the technology described in paragraph (4), if any, to reduce the concentration of that contaminant in drinking water to a level at or below the public health goal. (6) Briefly describes what action, if any, the local water purveyor intends to take to reduce the concentration of the contaminant in public drinking water supplies and the basis for that decision.
City of Santa Clara 12 2025 Public Health Goals Report
ATTACHMENT 3
City of Santa Clara Consumer Confidence Reports:
• Consumer Confidence Report 2022
• Consumer Confidence Report 2023
• Consumer Confidence Report 2024
Each year we publish our annual water quality report known as the Consumer Confidence Report (report). It contains the latest water quality monitoring results obtained through the end of calendar year 2022. It answers some of the most common water quality questions asked by our customers. We hope it will provide the facts and perspectives you need to make an informed evaluation of your tap water.
In order to ensure that tap water is safe to drink, the U.S.
Environmental Protection Agency (USEPA) and the State
Water Resources Control Board (State Water Board) prescribe regulations that limit the amount of certain contaminants in water provided by public water systems. The U.S. Food and Drug Administration regulations and California law also establish limits for contaminants in bottled water that provide the same protection for public health.
This report has been prepared in accordance with the
requirements of the Safe Drinking Water Act and State
regulations. Although the water you receive is tested for over 100 potential contaminants and 48 other parameters, most of the potential contaminants are never detected. To simplify the report, only the constituents that were detected in at least one water source appear in the water quality table. We are also required by the State to provide additional information about certain constituents that appear on the water quality table even though the water meets all applicable drinking water standards. The State allows us to monitor for some contaminants less than once per year because
the concentrations of these contaminants do not change
frequently. Due to regulatory monitoring schedules, some data, though representative, are more than one year old.
Report
Contains Water
Quality Monitoring
Results
Published June 2023
The City of Santa Clara is committed to
providing our customers with a safe and
reliable supply of high-quality drinking
water.
Some people may be more vulnerable to contaminants in drinking water than the general population.
Immuno-compromised persons such as persons with cancer undergoing chemotherapy, persons who have undergone organ transplants, people with HIV/AIDS or other immune system disorders, some elderly, and infants can be particularly at risk from infections. These people should seek advice about drinking water from their health care providers. USEPA/Center for Disease Control (CDC) guidelines on appropriate means to lessen the risk of infection by Cryptosporidium, and other microbial contaminants are available from the Safe Drinking Water Hotline (1-800-426-4791).
INFORMATION
AND GUIDANCE
FOR PEOPLE WITH
COMPROMISED
IMMUNE SYSTEMS:
2022
Water
Quality
Consumer
Confidence
Report
Drinking Water Must Meet Standards
The quality of drinking water is carefully regulated by the Federal Government. In 1974, Congress passed the Safe Drinking Water Act, requiring the USEPA to establish uniform standards for drinking water. The Safe Drinking Water Act was further amended in 1986 and 1996, adding even more stringent standards. In California, these standards are enforced by State Water Resources Control Board, Division of Drinking Water.
THERE ARE TWO TYPES OF DRINKING WATER STANDARDS
PRIMARY STANDARDS are designed to protect public health.
These standards specify the limits, called "Maximum Contaminant Levels" (MCLs) for substances in water that may be harmful to humans or affect their health if consumed in large quantities.
SECONDARY STANDARDS are based on aesthetic qualities of water such as color, taste and odor. These standards specify limits for substances that may affect consumer acceptance of the water.
Both Primary and Secondary Standards are listed in
this report.
It is important to the City of Santa Clara that you, the water consumer, have current and factual information about your water supply. In this latest issue of our report, we hope to further your understanding and strengthen your confidence in the quality and integrity of the water supplied to you by the City of Santa Clara.
We take great pride in delivering the safest and highest quality water available.
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 share access to the report at SantaClaraCA.gov/WaterQualityReport and post in a public place or distribute paper copies by hand or mail. Paper copies of the report are available for free at City Hall, City Libraries and the Senior Center, or by e-mailing [email protected] or calling 408- 615-2000 to request a paper copy.
Source Water Information
The City of Santa Clara has three separate
sources of drinking water. These sources
are used interchangeably or are blended
together. Altogether these sources
provide an average of 15 million gallons of
water per day to the homes, businesses,
industries and institutions of Santa Clara.
In 2022, about 39% of our water was
treated surface water purchased from the
Santa Clara Valley Water District (Valley
Water), imported from the Sacramento-San
Joaquin Delta, and from the San Francisco
Public Utility Commission’s (SFPUC) Hetch-
Hetchy Reservoir, imported from the Sierra
Nevada Mountains.
Water purchased from Valley Water
serves primarily the southwesterly
portion of the City. SFPUC Hetch-Hetchy
water typically serves the area north
of Highway 101. The remaining 61% is
pumped from the City’s system of 19
active wells serving the rest of Santa
Clara. The map shows the general areas
served by the different water sources.
CITY WELLS
The majority of water consumed in the
City of Santa Clara is pumped from the
City’s system of deep wells. Well water
is pulled up from groundwater (water
that is located in aquifers which are
waterfilled spaces between sand, gravel,
and silt deep in the ground). Aquifers are
replenished by rainwater that infiltrates
down from the land surface.
HETCH HETCHY SYSTEM
The City purchases water from the Hetch
Hetchy Reservoir. To meet drinking water
standards for consumption, all surface
water supplies including the upcountry
non-Hetch Hetchy sources (UNHHS)
undergo treatment by the San Francisco
Regional Water System (SFRWS) before
it is delivered. Water from Hetch Hetchy
Reservoir is exempt from federal and
state filtration requirements but receives
the following treatment: disinfection using
ultraviolet light and chlorine, pH adjustment
for optimum corrosion control, fluoridation for
dental health protection, and chloramination
for maintaining disinfectant residual and
minimizing the formation of regulated
disinfection byproducts. Water from local Bay
Area reservoirs in Alameda County and UNHHS
is delivered to Sunol Valley Water Treatment
Plant (SVWTP); whereas water from local
reservoirs in San Mateo County is delivered to
Harry Tracy Water Treatment Plant (HTWTP).
Water treatment at these plants consist of
filtration, disinfection, fluoridation, optimum
corrosion control, and taste and odor removal.
The SFRWS conducts watershed sanitary
surveys for the Hetch Hetchy source annually
and for non-Hetch Hetchy surface water
sources every five years. The latest sanitary
surveys for the non-Hetch Hetchy watersheds
were completed in 2021 for the period of
2016-2020. All these surveys, together with
SFRWS’s stringent watershed protection
management activities, were completed with
support from partner agencies including
National Park Service and US Forest Service.
The purposes of the surveys are to evaluate
the sanitary conditions and water quality
of the watersheds and to review results of
watershed management activities conducted
in the preceding years. Wildfire, wildlife,
livestock, and human activities continue to be
the potential contamination sources. You may
contact the San Francisco District office of the
State Water Resources Control Board’s Division
of Drinking Water (SWRCB) at 510-620-3474
for the review of these reports.
VALLEY WATER
Valley Water provides treated surface water to
local municipalities and private water retailers
who deliver the water directly to homes and
businesses in Santa Clara County. Valley Water’s
surface water is mainly imported from the
South Bay Aqueduct, Dyer Reservoir, Lake Del
Valle, and San Luis Reservoir, which all draw
water from the Sacramento - San Joaquin Delta
watershed. Calero Reservoir is Valley Water’s
local water source. Water from imported and
local sources is pumped to and treated at
three water treatment plants located in Santa
Clara County.
Currently, Valley Water is unable to utilize
Anderson Dam for local water storage due
to the rehabilitation of Anderson Dam, and
the Anderson Dam Seismic Retrofit Project
which will improve public safety and restore
operational capacity. This project will take 10
years to complete.
Valley Water’s source waters are vulnerable
to potential contamination from a variety of
land use practices, such as agricultural and
urban runoff, recreational activities, livestock
grazing, and residential and industrial
development. The imported sources are
also vulnerable to wastewater treatment
plant discharges, seawater intrusion, and
wildfires in open space areas. In addition,
local sources are also vulnerable to potential
contamination from commercial stables and
historic mining practices. No contaminant
associated with any of these activities has
been detected in Valley Water’s treated water.
The water treatment plants provide multiple
barriers for physical removal of contaminants
and disinfection of pathogens. For more
information, visit Valley Water’s website at
www.valleywater.org.
WATER SYSTEM IMPROVEMENTS
In an effort to continually maintain a high level
of service and supply quality potable water to
our customers, the City embarked on several
capital improvement projects to our water
system. In March 2022, three water tanks
were rehabilitated with seismic and safety
upgrades, recoated interior and exterior of the
tanks and added cathodic protection and tank
mixers. These tanks store 13.2 million gallons
of water, enough water to meet the entire
City’s demand for one average spring day.
Additionally, the City performs the design and
construction of water main replacements and
rehabilitation of ground water wells.
City of Santa Clara, California
0 1/ 2 1
Blend of SFPUC
Hetch Hetchy
System and
Groundwater
a Blend of Valley
Water Treated
Surface Water and
Groundwater
cCity of Santa Clara
Groundwater
b
THE CITY OF
SANTA CLARA OWNS
AND OPERATES
GROUNDWATER
WELLS.
Source water boundaries are approximate
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TASMAN
{a)
MONROE
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EL CAMINO REAL
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Definitions and Notes
Primary Drinking Water Standard (PDWS) = MCLs and
MRDLs for contaminants that affect health along with their monitoring and reporting requirements, and water treatment requirements.
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 CONTAMINANT LEVEL GOAL (MCLG) = The
level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs are set by the U.S. Environmental Protection Agency.
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.
PUBLIC HEALTH GOAL (PHG) = The level of a contaminant
in drinking water below which there is no known or expected risk to health. PHGs are set by the California Environmental Protection Agency.
REGULATORY ACTION LEVEL (AL) = The concentration of a
contaminant which, if exceeded, triggers treatment or other requirements that a water system must follow.
TREATMENT TECHNIQUE (TT) = A required process intended to reduce the level of a contaminant in drinking water.
UNREGULATED CONTAMINANTS = Unregulated
contaminant monitoring helps EPA and State Water Resources Control Board to determine where certain contaminants
occur and whether the contaminants need to be regulated.
The list of unregulated contaminants to monitor is updated every four years by the EPA.
pCi/L = picocuries per liter (a measure of radioactivity) PPM = Parts Per Million
PPB = Parts Per Billion
DISTRIBUTION SYSTEM = drinking water delivery system
RESIDENTIAL TAPS = household faucets used for lead and
copper sampling
DISINFECTION BYPRODUCTS = chemical by products of
disinfection
SECONDARY STANDARDS = secondary MCLs are set to
protect the aesthetics of drinking water
NTU = Nephelometric Turbidity Unit. Turbidity is a measure of the cloudiness of the water. We monitor it because it is a good indicator of water quality.
uS/cm = microSiemens per centimeter
NA = not applicable or available
ND = not detected
NS = no standard
Copper and Lead Tap Monitoring was performed at 52
residential taps in September 2022.
HARDNESS = the sum of polyvalent cations present in the water, generally magnesium and calcium. The cations are usually naturally occurring.
SODIUM = refers to the salt present in the water and is generally naturally occurring.
Attention
This report contains important information about
your drinking water. Translate it, or speak with
someone who understands it.
Mahalaga ang impormasyong ito. Mangyaring ipasalin ito.
Attencion: Este informe contiene informacion muy
importante sobre su agua beber. Traduzcalo o hable con
alguien que lo entienda bien.
Notes
(1) Natural fluoride in the Hetch Hetchy source was ND. (2) These are monthly average turbidity values calculated from turbidity measured every four hours daily. (3) In 2022, Boron was detected at a level of 1,300 ppb in the raw water stored in Pond F3 East, one of the SFRWS’s approved sources in the Alameda Watershed. The corresponding level in the treated water from the SVWTP was only 110 ppm due to blending with water from San Antonio Reservoir in the influent pipeline to the treatment plant. (4) John Sutter Elementary 2018 Result - 26ppb. Repeat sampling following plumbing repairs was non-detect for lead.
City of Santa Clara
WATER QUALITY TABLE
analysis for
City SC Well Water
analysis for
VALLEY WATER
analysis for
HETCH HETCHYState PHG/
Fed (MCLG)UNIT MCL range average range average range average Common Sources of:
Primary Standards For Source Water Sampling: or [max]
MICROBIOLOGICAL
giardia lamblia cyst/L TT 0 NA NA NA NA 0 - 0.04 0.01 naturally present in environment
RADIOACTIVITY
Gross Alpha pCi/L 15 (0) ND ND NT NT ND ND erosion of natural deposits
INORGANIC CHEMICAL
Barium PPM 1 2 ND - 0.12 ND ND ND ND ND erosion of natural deposit/oil drilling Fluoride PPM 2 1 0.15 - 0.22 0.18 ND - 0.13 ND ND - 0.8 0.3 (1) water additive/erosion of natural deposits Nitrate (as Nitrogen) PPM 10 10 1.1 - 5.2 3.7 ND - 0.7 0.4 ND ND erosion of natural deposit/runoff/leaching Secondary Standards: "Consumer Acceptance Contaminent Levels" Chloride PPM 500 NA 40 - 68 53 71 - 95 83 < 3 - 15 8.7 runoff/leaching natural deposits/seawater Color UNITS 15 NA ND ND ND - 5 2 < 5 - 5 < 5 naturally occuring organic material Iron PPB 300 NA ND ND < 20 <20 < 6 - 24 11 leaching from natural deposits/ind. wastes Odor UNITS 3 NA ND ND 1 1 ND ND naturally occuring organic material Foaming Agents (MBAS) PPB 500 NA ND-58 19 < 0.10 < 0.10 ND ND Municipal and ind. waste discharges Sp. Conductance uS/cm 1600 NA 609 - 782 681 562 - 626 581 37 - 210 140 subst. forming ions/seawater intrusion Sulfate PPM 500 NA 34 - 50 41 50 - 74 65 1.1 - 29 15 runoff/leaching natural deposits/ind. waste Tot.Dissolved Solids PPM 1000 NA 384 - 460 417 308 - 362 335 < 20 - 104 61 runoff/leaching from natural deposits Turbidity NTU 5 NA ND - 0.43 0.2 0.01 - 0.28 0.06 0.2 - 0.4 (2) [3.4] soil runoff Consumer Information
pH UNITS NS NS 7.5 - 9.5 8.0 7.5 - 8.0 7.8 8.2 - 9.6 9.2 Alkalinity (as CaCO3) PPM NS NS 191 - 287 239 61 - 78 73 7.1 - 166 41 Ammonia (NH3-N) PPM NS NS NA NA 0.44 - 0.55 0.50 NA NA
Bicarbonate Alkalinity (as HCO3) PPM NS NS 191 - 287 239 74 - 95 86 NA NA Boron PPB NS NS NA NA 126 - 182 163 28 - 105 (3) 56
Bromide PPB NS NS NA NA ND - 160 78 ND ND
Calcium (as Ca) PPM NS NS 71 - 90 84 17 - 25 23 3.2 - 15 9.3 Chlorate PPB NS NS NA NA 96 - 221 150 45 - 650 147
Hardness PPM NS NS 250 - 320 296 92 - 122 114 9.1 - 49 32 Hexavalent Chromium PPB NS 0.02 1.0 - 2.5 1.7 < 1.00 < 1.00 0.22 - 0.27 0.25 Magnesium PPM NS NS 18 - 24 21 12 - 15 14 0.2 - 4.2 2.9 Phosphate PPM NS NS NA NA 1.02 - 1.17 1.08 ND ND
Potassium PPM NS NS 1.2 - 1.5 1.3 3.6 - 4.6 4.1 0.3 - 1 0.7 Silica PPM NS NS NA NA 7 - 14 11 5 - 5.9 5.5
Sodium PPM NS NS 24 - 32 27 65 - 79 71 3.5 - 21 14
Strontium pCi/ L NS NS NA NA NA NA 16 - 159 79
Temperature Deg. C NS NS 11 - 26 19 14 - 22 19 NA NA
Total Organic Carbon PPM NS NS NA NA 1.5 - 3.0 2.3 1.3 - 3.9 2.3 Vanadium PPB NS NS NA NA 2 - 3 2 NA NA
Primary Standards As Measured In City Of Santa Clara Distribution System:
Units MCL State MCL Range Average Common Sources of:
MICROBIOLOGICAL (Fed PHG)
Total Coliform % pos (+) 5.00% (0) 0 - 0.1% < 5% naturally present in environment Fecal Coliform and E.coli (3) # of pos (+) 0 0 0 0 human and animal fecal waste
DISINFECTION BYPRODUCTS, RESIDUALS, PRECURSORS
Trihalomethanes PPB 80 NA ND - 57 [54.8] byproduct of drinking water disinfection Haloacetic Acids PPB 60 NA ND - 39 [37.8] byproduct of drinking water disinfection Chlorine residual PPM 4 4 0.0 - 3.9 1.03 drinking water disinfectant INORGANIC CHEMICAL as measured at 52 Residential Taps in 2022:
Copper PPM AL = 1.3 0.3 90th percentile = 0.47 ppm Number Exceeded = 0 corrosion of plumbing systems Lead PPB AL = 15 0.2 90th percentile = ND Number Exceeded = 0 corrosion of plumbing systems SCHOOLS REQUESTING LEAD TESTING IN 2018: 33 Schools (172 samples taken) Lead PPB AL = 15 0.2 90th percentile = ND Number Exceeded = 1 (4) corrosion of plumbing systems Unregulated Contaminants As Measured In City Of Santa Clara Distribution System:
Units Notification Level Range Average
Total Haleoacetic Acids (9) PPB NA ND - 58 23.6
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Fluoride is nature’s cavity fighter. Fluoridation adjusts the naturally occurring fluoride in drinking water to the ideal level for protecting your teeth. Fluoridated drinking water benefits people of all ages by preventing tooth decay.
The water purchased by the City from the SFPUC is fluoridated, while water from Valley Water is not fluoridated. If your zip code is 95054, you are in the area receiving fluoridated water. However, this area is also served by well water that has not been fluoridated.
Fluoridated water from SFPUC is blended with well water. Refer to the map that shows the area supplied with water from both the Hetch-Hetchy system and the City’s wells. The majority of the City will continue to receive water without added fluoride.
State law requires the addition of fluoride to all water systems in California serving 10,000 customers or more. In the future, Valley Water plans to add fluoridation to the Rinconada Water Treatment Plant which services the southern portion of Santa Clara.
Fluoridation of the remaining water sources in the City would require installation of fluoride injecting equipment at each of the City's 19 active wells. The law includes a provision for state funds to finance this fluoridation equipment; however; it may be some time before the state can provide funding to move forward with a fluoridation program for the remainder of the City.
Contact your health provider if you have concerns about dental fluorosis. For additional information about fluoridation or oral health, visit the CDC website www.cdc.gov/fluoridation or the State Water Board website https://www.waterboards.ca.gov/drinking_water/ certlic/drinkingwater/Fluoridation.html.
Some Santa Clara Water
is Flouridated
Water Quality Monitoring
INFORMATION ABOUT THE DRINKING WATER SOURCE
ASSESSMENT AND PROTECTION PROGRAM
The City completed a Drinking Water Source Assessment and Protection (DWSAP) Program for the groundwater sources. The DWSAP was completed in August 2002 and submitted to the State Water Resources Control Board in December 2002. A copy of the DWSAP is available at the City's Water Utility offices at 1500 Warburton Avenue, Santa Clara. You may request a summary of the individual assessments by contacting the Water Utility at (408) 615- 2000 or by email at [email protected].
The City's groundwater sources are considered most vulnerable to contamination by leaking underground tanks containing fuel or dry- cleaning chemicals; old, unrecorded septic systems; storm drain dry wells located at various places around the City; many old, shallow, private wells, abandoned and not properly destroyed; and possibly some contaminants from a small landfill dump left over from the early years of the 20th century.
LEAD
There have been no exceedances of the ACTION LEVEL for lead in the City of Santa Clara groundwater sources or supplies purchased from other agencies. It is possible for lead levels in your home to be higher than other homes in the community because of plumbing materials used in the original construction of your home. If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with service lines and home plumbing. The City of Santa Clara is responsible for providing high quality drinking water, but cannot control the variety of materials used in plumbing components. When your water has been sitting for several hours, you can minimize the potential for lead exposure by flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. If you are concerned about lead in your water, you may wish to have your water tested. Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the Safe Drinking Water Hotline (1-800-426-4791) or at http://www.epa.gov/lead.
“NITRATES” - INFORMATION ABOUT NITRATES IN
GROUNDWATER RESOURCES
Nitrate in drinking water at levels above 10 mg/L is a health risk for infants less than six months old. 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 10 mg/L may also affect the ability of the blood to carry oxygen in other individuals, such as pregnant women and those with certain specific enzyme deficiencies.
If you are caring for an infant, or you are pregnant, you should ask for advice from your health care provider.
PFAS
Perfluoroalkyl and Polyfluoroalkyl substances, collectively known as “PFAS” are a group of chemicals that have been widely used in industrial applications and consumer products such as carpets, clothing, furniture fabrics, paper packaging for food, firefighting foams, and other materials including waterproof/stain resistant/ nonstick cookware. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are two common types of PFAS. The City has completed monitoring for PFAS compounds at select well sites based on proximity to a potential source of contamination (airports which are known to have used aqueous film foaming agents for fire suppression and training). No PFAS compounds have been detected during monitoring. In October 2021, the City received a waiver for PFAS monitoring because PFAS was not detected in all collected samples.
CRYPTOSPORIDIUM AND GIARDIA IN WATER RESOURCES
Cryptosporidiosis is a disease of the intestinal tract brought on by a parasitic microbe (a protozoan) called Cryptosporidium. The disease is transmitted through contaminated water, food or direct contact with human or animal waste. If you are healthy with a normal immune system, the flu-like symptoms usually last about two weeks. Symptoms include diarrhea, stomach cramps, upset stomach and slight fever.
However, immuno-compromised people, infants, small children, and the elderly are at greater risk of developing life-threatening illness.
The water purchased by the City from the SFPUC Hetch Hetchy system has been tested for Cryptosporidium and Giardia. The source waters and treated waters are tested at least monthly and occasionally show very low levels of Cryptosporidium in the waters serving the East Bay, South Bay and San Francisco Peninsula. Giardia, another parasitic organism causing similar symptoms, is monitored with the same frequency and very low levels are occasionally detected in the same source waters.
The general public is at very low risk and there have been no reported cases of Cryptosporidiosis and Giardiasis attributed to the City’s public water supply. This advisory applies to water received from the Hetch Hetchy system in the area of the City north of Highway 101.
The California Department of Public Health (CDPH) issues guidance for people with serious immune system problems. Currently, available guidance from the state and county health agencies recommends that people with such conditions consult with their doctor or primary health care provider about preventing Cryptosporidium and Giardia infection from all potential sources. Water consumers may choose to boil their drinking water at a rolling boil for at least one minute as an extra precaution.
For information about Cryptosporidiosis and Giardiasis, or copies of available guidance, contact the Santa Clara County Department of Environmental Health at 408 918-3400. You may also contact the USEPA Drinking Water Hotline at 1-800-426-4791.
CONTAMINANTS THAT OCCUR IN DRINKING WATER
OBTAINED FROM SURFACE SOURCES AND UNDERGROUND
SOURCES
Sources of drinking water (both tap water and bottled water) include rivers, lakes, streams, ponds, reservoirs, springs, and wells. As water travels over 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 human activity.
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 resulting from urban stormwater 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 stormwater runoff and residential uses; • Organic chemical contaminants including synthetic and volatile organic chemicals. that are by-products of industrial processes and petroleum production, and can also come from gas stations, urban stormwater runoff, agricultural application, and septic systems;
• Radioactive contaminants, that can be naturally occurring or be the result of oil and gas production and mining activities.
In order to ensure that tap water is safe to drink, the U.S Environmental Protection Agency (USEPA) and the State Water Resources Control Board (State Water Board) prescribe regulations that limit the amount of certain contaminants in water provided by public water systems. The U.S. Food and Drug Administration regulations and California law also establish limits for contaminants in bottled water that provide the same protection for public health.
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.
More information about contaminants and potential health effects can be obtained by calling the USEPA’s Safe Drinking Water Hotline at 1-800-426- 4791.
WATER CONSERVATION
Due to improved drought conditions and record snow survey conducted by the Department of Water Resources, on March 24, 2023, Governor Newsom issued an Executive Order ending the State of California’s voluntary 15% water conservation target. In response to the improved water supply conditions, the Governor’s Executive Order and City water suppliers, Valley Water and San Francisco Public Utilities Commission rescinding the drought emergency, City of Santa Clara’s Council also rescinded the local drought emergency on May 9, 2023. However, the State Water Resources Control Board conservation emergency regulations still remain in place and Valley Water is also maintaining a 15% voluntary conservation requirement. Therefore, the City continues to maintain a 15% voluntary conservation and other water conservation measures. We must permanently adopt the drought adaptations we have made, making them part of a conservation mindset and lifestyle that sustains Santa Clara regardless of California’s weather fluctuations.
City of Santa Clara
1500 Warburton Ave.
Santa Clara, CA 95050
408-615-2200
SantaClaraCA.gov
Water Utility
1500 Warburton Ave.
Santa Clara, CA 95050
Office hours: 8 a.m.–5 p.m.,
Monday-Friday
408-615-2000
Water Billing Questions
408-615-2300
Water Conservation
SantaClaraCA.gov/
WaterConservation
Water Quality Report Questions
Diane Asuncion
408-615-2000
[email protected]
Water Emergencies
408-615-2000 Monday-Friday,
8 a.m.-5 p.m.
408-615-5640 other days and times
Valley Water Water Conservation
ValleyWater.org/watersavingsorg
408-630-2554 – Water Conservation
Hotline and Rebate Information
Sign up for a free Water-Wise House
Call from Valley Water by calling
1-800-548-1882
Resources
If you would like to learn more about
drinking water quality, treatment and
regulation, contact these organizations:
American Water Works Association
AWWA.org
State Water Resources Control Board,
Division of Drinking Water
www.waterboards.ca.gov/drinking_
water/programs/index.html
United States Environmental
Protection Agency
water.epa.gov/drink
San Francisco Public Utilities
Commission, Water Quality Bureau
SFWater.org
Valley Water
ValleyWater.org
Water Education Foundation
WaterEducation.org
Water Quality & Agriculture Info Center
www.nal.usda.gov/legacy/waic
Public Input
To provide input on decisions that affect
drinking water quality, provide input to the
Santa Clara City Council at a Council meeting
or in advance to mayorandcouncil@
santaclaraca.gov or call 408-615-2250. A
list of all City Council meetings, agenda items
and study sessions can be viewed on the City
website at SantaClaraCA.gov/Meetings
eNotify
Visit SantaClaraCA.gov/eNews to sign up
to receive news from Water Utility.
For Additional Information On Water Quality
Published June 2024
2023
Water Quality
Consumer Confidence Report
ssible
Our naturally clean tap
water comes from three
sources that are used
interchangeably or are
blended:
Santa Clara Drinking Water Sources
They provide an average of 15 million gallons of water per day to Santa Clara’s residential & commercial communities.
Valley Water’s source serves primarily the southwesterly portion of the City. San Francisco Public Utility Commission (SFPUC) water typically serves the area north of Highway 101. The remaining water is pumped from the City’s system of 20 active wells serving the rest of Santa Clara. The map shows the general areas served by each source.
Assessed much more frequently than bottled water, Santa Clara’s tap water undergoes rigorous regular testing and monitoring for over 100 potential contaminants and dozens of other parameters to ensure our drinking water meets Federal and State standards for health.
Santa Clara takes
pride in delivering
safe, reliable,
high-quality
drinking water
Each year we publish the Water Quality
Consumer Confidence Report, containing the
latest water quality monitoring results through
the end of the prior calendar year and answering
the most common customer questions. We hope
it provides facts and perspectives you need to
make an informed evaluation of your tap water.
Drinking water quality is carefully regulated by the
Federal Government with the Safe Drinking Water
Act, requiring the U.S. EPA to establish uniform
standards that are enforced by the State Water
Resources Control Board (SWRCB), Division of
Drinking Water.
The 2023 Water Quality Report is prepared
in accordance with requirements of the Safe
Drinking Water Act and State regulations. To
simplify the report, only constituents that were
detected in at least one water source appear in
the water quality table. As required by the State,
we also provide additional information for certain
constituents appearing on the water quality table
though the water meets all applicable drinking
water standards.
PRIMARY STANDARDS are designed to protect
public health, specifying limits called "Maximum
Contaminant Levels" (MCLs) for substances in
water that may be harmful to humans or affect
health if consumed in large quantities.
SECONDARY STANDARDS are qualities such as
color, taste and odor, specifying limits for
substances that may affect consumer
acceptance of the water.
The State allows us to monitor some
contaminants less than once per year since their
concentrations don’t change frequently. Due to
regulatory monitoring schedules, some data are
more than one year old.
The Drinking Water Source Assessment and
Protection (DWSAP) Program completed and
submitted to the SWRCB in 2002 is available at
the Water & Sewer Utilities Office at City Hall. You
may request a summary by calling (408) 615-
2000 or by emailing
[email protected].
Information & Guidance
for People With
Compromised Immune
Systems
Some people may be more vulnerable to
contaminants in drinking water than the general
population. People with cancer undergoing
chemotherapy, those who have undergone organ
transplants, those with HIV/AIDS or other immune
system disorders, some elderly, infants and other
immuno-compromised people can be particularly
at risk from infections and should seek advice
about drinking water from their health care
providers. Guidelines for ways to lessen the risk
of microbial contaminant infection: United States
Environmental Protection Agency (U.S. EPA) Safe
Drinking Water Hotline: 1(800) 426-4791.
Please share this Water Quality Report with all
people who drink City tap water, especially if
they may not have received this notice directly
(those in apartments, nursing homes, schools and
businesses).
Share access to the Water Quality Report at
SantaClaraCA.gov/WaterQualityReport. Post it
in a public place or distribute paper copies by
hand or mail.
Free paper copies of the 2023 Water Quality
Consumer Confidence Report are available at:
• City Hall
• City Libraries
• Santa Clara Senior Center
• Community Recreation Center
• By request: [email protected]
or (408) 615-2000
Water System
Improvements
The City performed several capital improvement
projects to maintain a high level of service and
provide quality potable water to our customers.
Our Water Main Replacement Program
successfully met its annual goal of replacing
10,000 linear feet of aging water main in 2023.
Replacement mains were upsized to standard 8-
or 12-inch new zinc coated, ductile iron mains.
The replacement water mains will improve water
quality and system resilience.
Well Rehabilitation
Two well rehabilitation projects, Wells 34 and 23,
began toward the end of 2023; Well 23 had been
inactive since 2017. The projects include repairs
and replacement to the existing pump/motor and
well redevelopment. Both wells are expected to
return to service in 2024.
In addition to our capital improvement projects,
the City conducts storage tank maintenance,
cross connection tests, and flushing programs to
protect our water quality year-round.
1. Protected groundwater wells within the City, tapping aquifers 500 to 900 feet deep
2. Local reservoirs, rivers feeding the Sacramento Delta, and others from Valley Water, our local water wholesaler
3. Snowmelt from the Sierra Nevada Mountains via the
San Francisco Public Utilities Commission’s Hetch Hetchy Reservoir Santa Clara,
California
Blend of SFPUC
Hetch Hetchy
System and
Groundwater
a
Blend of Valley
Water Treated
Surface Water
and Groundwater
c
City of
Santa Clara
Groundwater
b
Source water
boundaries are
approximate
Source Water Information
City Groundwater Wells
Most of our water is pumped from the City’s system of deep wells. Well water is pulled up from aquifers. Replenished by rainwater that infiltrates down from the land surface, aquifers are waterfilled spaces deep in the ground that collect rain naturally filtered through layers of sand, gravel, and silt.
SFPUC System
The City purchases water from the SFPUC, which is exempt from Federal and State filtration requirements, but receives the following treatments, meeting all drinking water standards:
• Disinfection using ultraviolet light and chlorine
• pH adjustment for optimum corrosion control
• Fluoridation for dental health
• Chloramination to maintain disinfectant residual &
minimize the formation of regulated disinfection
byproducts
Valley Water
Valley Water’s treated surface water is mainly imported from the South Bay Aqueduct, Dyer Reservoir, Lake Del Valle, and San Luis Reservoir, which all draw water from the Sacramento - San Joaquin Delta watershed. Calero Reservoir is Valley Water’s local water source. Imported and locally sourced water is pumped to three water treatment plants in the County. Valley Water provides water to Santa Clara from the Rinconada Water Treatment Plant.
Visit the City’s Water Quality webpage for more information:
SantaClaraCA.gov/WaterQuality
This Water Quality Consumer
Confidence Report Details:
• The City’s water sources and
their distribution.
• Federal and State standards
that drinking water must meet.
• Specific standards and
contaminants for which
each of our water sources is
monitored and tested.
• Required information
explaining why certain
contaminants (lead,
nitrates, perfluoroalkyl and
polyfluoroalkyl substances
(PFAS), etc.) are monitored.
Since the City’s first water service in
1894, reliably serving high-quality
drinking water has been the top
priority of Water & Sewer Utilities. With
turn-of-the-tap convenience, Santa
Clarans enjoy fresh, clean drinking
water at about 1¢ per gallon.
We encourage the public to
hydrate locally. Take full, cost-
effective advantage of California-
sourced drinking water, pure and
uncompromised by questionable
plastic packaging, no bulk storage
required. Grab a stainless steel or
glass bottle and fill up fresh from the
tap with clean California water to-go or
enjoy at home. Drink Santa Clara’s tap
water with confidence to the health
of your family, our community and the
environment.
UNIT MCL State PHG/
Fed (MCLG)
Analysis for
City SC Well Water
Analysis for
VALLEY WATER
Analysis for
SFPUC Common Sources
Range Average Range Average Range Average
Primary Standards For Source Water Sampling: [highest running average]
MICROBIOLOGICAL
Giardia lamblia cyst/L TT 0 NA NA NA NA 0 - 0.13 0.03 naturally present in environment
RADIOACTIVITY
Gross Alpha pCi/L 15 (0) NA NA 3.3 3.3 ND ND erosion of natural deposits Uranium pCi/L 20 0.43 NA NA 1.3 1.3 ND ND erosion of natural deposits
INORGANIC CHEMICAL
Barium PPM 1 2 0.09 - 0.13 0.11 ND ND ND ND erosion of natural deposit/oil drilling Fluoride PPM 2 1 0.14 - 0.17 0.16 ND - 0.16 ND 0.4 - 2.6 0.6 water additive/erosion of natural deposits Nitrate (as Nitrogen) PPM 10 10 0.93 - 5.3 3.4 ND - 1.3 0.6 ND - 0.6 ND erosion of natural deposits/runoff/leaching Secondary Standards: "Consumer Acceptance Contaminent Levels" Chloride PPM 500 NA 34 - 47 43 11 - 52 37 <3 - 9.3 4.6 runoff/leaching natural deposits/seawater Color UNITS 15 NA ND ND 1 - 5 4 < 5 - 5 < 5 naturally occuring organic material Iron PPB 300 NA ND ND < 20 <20 < 6 - 42 21 leaching from natural deposits/industrial wastes Odor UNITS 3 NA ND ND 1.4 - 2.0 1.9 ND ND naturally occuring organic material Manganese PPB 50 NA ND ND < 1.0 < 1.0 3.1 - 4.6 3.8 leaching from natural deposits Specific Conductance uS/cm 1600 NA 559 - 690 622 188 - 463 369 32 - 289 160 substances that form ions when in water Sulfate PPM 500 NA 40 - 50 46 34 - 78 56 1.2 - 36 19 runoff/leaching natural deposits/industrial waste Total Dissolved Solids PPM 1000 NA 364 - 444 391 112 - 272 213 <20 - 153 77 runoff/leaching from natural deposits Turbidity NTU 5 NA ND - 1.3 0.37 0.03 - 0.30 0.05 0.1 - 0.6 (1) [0.3] soil runoff Consumer Information
pH UNITS NS NS 7.6 - 7.8 7.7 7.4 - 7.9 7.6 8.4 - 9.8 9.3 Alkalinity (as CaCO 3) PPM NS NS 182- 220 200 36 - 62 54 3.1 - 103 44 Aluminum PPB 1000 600 ND ND ND ND ND - 82 ND
Bicarbonate Alkalinity (as HCO 3) PPM NS NS 182 - 220 200 43 - 76 66 NA NA Boron PPB NS NS NA NA ND - 167 ND 22 - 65 43
Bromomethane PPB NS NS ND - 0.14 ND < 0.50 < 0.50 ND ND Calcium (as Ca) PPM NS NS 63 - 75 69 10 - 25 18 2.9 - 24 13 Chlorate (2) PPB NS NS NA NA 68 - 108 84 30 - 749 168
Hardness PPM NS NS 250 - 300 270 42 - 114 82 7.5 - 86 47 Hexavalent Chromium PPB 10 (3) 0.02 2.3 - 3.9 2.9 < 1.00 < 1.00 0.11 - 0.35 0.23 Magnesium PPM NS NS 17 - 31 24 4 - 13 9 0.2 - 8.4 4.3
Phosphate PPM NS NS NA NA 1.03 - 1.11 1.08 ND ND
Potassium PPM NS NS 1.2 - 1.3 1.2 1.6 - 3.6 2.8 0.3 - 1.7 1.0 Silica PPM NS NS NA NA 10 - 14 12 4.9 - 9.4 7.1
Sodium PPM NS NS 23 - 26 24 20 - 52 40 2.7 - 19 11
Strontium pCi/ L NS NS NA NA NA NA 14 - 331 173
T-Butyl alcohol (TBA) PPB NS NS ND - 2.3 ND < 2.0 < 2.0 NA NA Temperature Deg. C NS NS 10 - 25 19 12.5 - 21.0 17.3 NA NA Total Organic Carbon PPM NS NS NA NA 1.2 - 2.2 1.8 1.2 - 1.8 [1.5] Vanadium PPB NS NS NA NA 1 - 2 1 NA NA
Primary Standards As Measured In City Of Santa Clara Distribution System:
UNITS MCL State MCL Range Average Common Sources
MICROBIOLOGICAL (Fed PHG)
Total Coliform % pos (+) 5.00% (0) 0 - 2.1% < 5% naturally present in environment Fecal Coliform and E.coli (4) # of pos (+) 0 0 0 0 human and animal fecal waste
DISINFECTION BYPRODUCTS, RESIDUALS, PRECURSORS
Trihalomethanes PPB MRDL = 80 NA ND - 86 [67.0] disinfection byproduct Haloacetic Acids PPB MRDL = 60 NA ND - 68 [46.0] disinfection byproduct Chlorine residual (5) PPM MRDL = 4 4 0.0 - 4.8 0.9 drinking water disinfectant INORGANIC CHEMICAL as measured at 52 Residential Taps in 2022:
Copper (6) PPM AL = 1.3 0.3 90th percentile = 0.47 ppm Number Exceeded = 0 corrosion of plumbing systems Lead (6) PPB AL = 15 0.2 90th percentile = ND Number Exceeded = 0 corrosion of plumbing systems SCHOOLS REQUESTING LEAD TESTING IN 2018: 33 Schools (172 samples taken) Lead PPB AL = 15 0.2 90th percentile = ND Number Exceeded = 1 (7) corrosion of plumbing systems Unregulated Contaminants As Measured In City Of Santa Clara Distribution System:
UNITS Notification Level Range Average
Total Haleoacetic Acids (9) PPB NA ND - 58 23.6
Definitions
DISINFECTION BYPRODUCTS = chemical
byproducts of disinfection
DISTRIBUTION SYSTEM = drinking water
delivery system
HARDNESS = the sum of polyvalent cations
present in the water, generally magnesium
and calcium. The cations are usually naturally
occurring.
MAXIMUM CONTAMINANT LEVEL (MCL) =
The highest level of a contaminant 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 CONTAMINANT LEVEL GOAL
(MCLG) = The level of a contaminant in drinking
water below which there is no known or
expected risk to health. MCLGs are set by the
U.S. EPA.
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.
NA = not applicable or available
ND = not detected
NS = no standard
NTU = Nephelometric Turbidity Unit. Turbidity
is a measure of the cloudiness of the water.
We monitor it because it is a good indicator of
water quality.
pCi/L = picocuries per liter (a measure of
radioactivity)
PPB = Parts Per Billion (µg/L)
PPM = Parts Per Million (mg/L)
PRIMARY DRINKING WATER STANDARDS
(PDWS) = MCLs and MRDLs for contaminants
that affect health along with their monitoring
and reporting requirements, and water
treatment requirements.
PUBLIC HEALTH GOAL (PHG) = The level of
a contaminant in drinking water below which
there is no known or expected risk to health.
PHGs are set by the California EPA.
REGULATORY ACTION LEVEL (AL) =
The concentration of a contaminant which,
if exceeded, triggers treatment or other
requirements that a water system must follow.
RESIDENTIAL TAPS = household faucets used
for lead and copper sampling
SECONDARY STANDARDS = secondary
MCLs are set to protect the aesthetics of
drinking water
SODIUM = refers to the salt present in the water
and is generally naturally occurring.
TREATMENT TECHNIQUE (TT) = A required
process intended to reduce the level of a
contaminant in drinking water.
UNREGULATED CONTAMINANTS =
Unregulated contaminant monitoring helps
EPA and SWRCB to determine where certain
contaminants occur and whether the
contaminants need to be regulated. Every four
years, the EPA updates the list of unregulated
contaminants to monitor.
uS/cm = microSiemens per centimeter
Notes
(1) These are monthly average turbidity values
calculated from turbidity measured every four
hours daily.
(2) The detected chlorate in the treated water is
a degradation product of sodium hypochlorite
used by the San Francisco Regional Water
System for water disinfection.
(3) The rulemaking to establish an MCL of
10 ppb (μg/L) for Hexavalent Chromium will be
finalized in 2024.
(4) The MCL was changed to E. coli starting
on July 1, 2021 when the State Revised Total
Coliform Rule became effective.
(5) Compliance for Chlorine residual MRDL is
based on running annual average.
(6) Copper and Lead Tap Monitoring was
performed at 52 residential taps in
September 2022.
(7) 2018 sampling result for John Sutter
Elementary was 26ppb. Repeat sampling
following plumbing repairs was non-detect
for lead.
City of Santa Clara
Water Quality Table
All Santa Clara
water sources
meet or exceed
Federal and
State standards.
The U.S. EPA and the State Water Resources Control Board (SWRCB) prescribe regulations that limit the amounts of certain contaminants in water provided by public water systems to ensure its safety. U.S. Food and Drug Administration regulations and California law also establish contaminant limits in bottled water to provide protection for public health, though it’s tested less frequently than tap water.
Drinking water, including bottled water, may be expected to contain small amounts of contaminants; their presence doesn’t necessarily indicate that the water poses a health risk.
Information about contaminants and potential health effects:
U.S. EPA’s Safe Drinking Water Hotline: 1(800) 426-4791 Some Santa Clara Water is Fluoridated
Fluoridation adjusts naturally occurring fluoride in drinking water to the ideal level for protecting your teeth. Water purchased by the City from the SFPUC is fluoridated, while water from Valley Water is not.
If you’re in zip code 95054, you receive fluoridated water from the SFPUC that may be blended with unfluoridated well water. The area receiving a blend of water from both SFPUC and City wells are shown on the source water map included in this report. The majority of Santa Clara will continue to receive water without added fluoride.
Have concerns about dental fluorosis? Contact your health care provider.
For more information, visit the CDC or SWRCB websites.
Naturally Occurring Drinking Water
Contaminants
Tap and bottled drinking water sources include rivers, lakes, streams, ponds, reservoirs, springs and wells. Travelling water dissolves naturally occurring minerals and, in some cases radioactive material, potentially picking up substances resulting from animal or human activity.
Naturally occurring source water contaminants may include:
• Microbials (viruses and bacteria) from sewage treatment plants, septic systems, agricultural livestock operations or wildlife • Inorganics (salts and metals): from stormwater runoff, wastewater discharges, oil and gas production, mining, farming or naturally occurring
• Pesticides/herbicides: from agriculture, stormwater runoff or landscaping
• Organic chemicals: byproducts of synthetic and volatile organic chemical industrial processes and petroleum production or gas stations, stormwater runoff, agricultural and septic systems • Radioactive contaminants: either naturally occurring or resulting from oil/gas production or mining activities
Lead
No Santa Clara water sources have exceeded the ACTION LEVEL for lead.
Lead levels in your home may be higher than others due to plumbing in your home’s original construction. Elevated lead levels can cause serious health problems, especially for pregnant women and young children.
Lead in drinking water comes from service line and home plumbing components. The City provides high quality drinking water, but cannot control materials used in your home’s plumbing. When water hasn’t been used for several hours, you can minimize potential lead exposure by:
1. Flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. (Use collected flushing water for cleaning, watering plants or running your garbage disposal.)
2. Using only cold water for drinking and cooking.
3. Concerned about lead in your water? For more information:
• epa.gov/lead
• Safe Drinking Water Hotline 1(800) 426-4791
Contaminant Regulations
Nitrates in Groundwater Resources
Nitrate levels above 10 mg/L in drinking water present health risks for infants under six months old. Such levels can interfere with the capacity of the infant’s blood to carry oxygen, resulting in serious illness. Likewise, nitrate levels above 10 mg/L may have the same effects in pregnant women or those with specific enzyme deficiencies. If you are pregnant or caring for an infant, consult your health care provider.
PFAS
Perfluoroalkyl and Polyfluoroalkyl substances, collectively known as “PFAS” are a group of chemicals that have been widely used in industrial applications and consumer products such as carpets, clothing, furniture fabrics, paper packaging for food, firefighting foams, and other materials including waterproof/stain resistant/nonstick cookware. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are two common types of PFAS. From 2019 to 2021, the City has completed monitoring for PFAS compounds at select well sites based on proximity to a potential source of contamination (airports which are known to have used aqueous film foaming agents for fire suppression and training). No PFAS compounds have been detected during monitoring. In October 2021, the City received a waiver for PFAS monitoring because PFAS were not detected in any collected samples.
The City will complete monitoring at 17 representative groundwater wells and two surface water turnouts for U.S. EPA’s Fifth Unregulated Contaminant Monitoring Rule for PFAS by the year 2025. No PFAS compounds have been detected during monitoring in 2023.
Hexavalent Chromium
Hexavalent Chromium, also known as Chromium-6, occurs naturally throughout California from the erosion of chromium deposits. It has also been utilized in variety of industrial activities, including the manufacturing of textile dyes, wood preservation, leather tanning, and anticorrosion coatings.
Currently, there is rulemaking in progress to establish the regulatory standard for Hexavalent Chromium at 10 µ g/ml.
SFPUC Water: Tested for
Cryptosporidium & Giardia
Monthly (or more frequent) tests of SFPUC source and treated waters occasionally show very low levels of Cryptosporidium and Giardia in water serving the East Bay, South Bay and San Francisco Peninsula.
Cryptosporidiosis, an intestinal tract disease brought on by a parasitic microbe called Cryptosporidium, transmits through contaminated water, food or direct contact with human or animal waste. Giardia is caused by a different parasitic organism, but causes similar flu-like symptoms. Cryptosporidiosis and Giardia symptoms usually last about two weeks for those with normal immune systems. Immuno-compromised people, infants, small children and the elderly are at greater risk of developing life-threatening illness.
Available guidance from the California Department of Public Health and County health agencies recommend that people with serious immune problems consult with their doctors or primary health care providers about preventing Cryptosporidium and Giardia infection from all potential sources.
Water consumers may choose to boil drinking water at a rolling boil for at least one minute as an extra precaution.
Cryptosporidiosis and Giardiasis information and guidance:
•
Sant
a Clara County Department of Environmental Health:
(408) 918-3400
•
U
.S. EPA Safe Drinking Water Hotline:
1(800) 426-4791
The Conservation Way of Life
Statewide rainfall year totals are 108% of average. Groundwater conditions remain healthy countywide. Yet the voluntary 15% water use reduction continues: Why?
1. Ander
son Reservoir, the largest locally, is offline for seismic
r
etrofit until 2032.
2. Ne
w State legislation, Making Conservation a California Way of Life, mandates urban water use reductions.
3. The ne
xt drought is around the corner.
Recognizing the drought reality, an emergency measure the State adopted during the last drought permanently bans drinking water for landscape use at commercial, industrial and institutional properties with AB 1572. More changes will come as the State faces an uncertain water future.
Conservation remains critical to ensure our drinking water supplies.
Santa Clara continues its downward trend in drinking water use, largely due to reduced outdoor watering. The City thanks residents and business owners who have taken conservation seriously. We must permanently adopt drought adaptations we have made, making them part of a conservation mindset and lifestyle that sustains Santa Clara regardless of California’s weather fluctuations. Do your part; maximize water resources and reduce water pollution using generous water rebates: SantaClaraCA.gov/WaterRebates City of Santa Clara
1500 Warburton Ave.
Santa Clara, CA 95050
408-615-2200
SantaClaraCA.gov
Water & Sewer Utilities
1500 Warburton Ave.
Santa Clara, CA 95050
Office hours: 8 a.m.–5 p.m., Mon–Fri
408-615-2000
Email: [email protected]
Water Emergencies
408-615-2000
Monday–Friday, 8 a.m.–5 p.m.
Water Billing Questions
408-615-2300
Water Quality Report Questions
Vikram Manke
408-615-2000
Email: [email protected]
Public Input
Provide input on decisions that affect drinking water
quality to Santa Clara City Council at a Council
meeting or in advance:
Email: [email protected]
or 408-615-2250.
A list of all City Council meetings, agenda items &
study sessions can be viewed on the City website at
SantaClara.Legistar.com/Calendar.aspx
Water Conservation and Rebates
SantaClaraCA.gov/WaterConservation
WaterSavings.org
ValleyWater.org
Water Conservation Hotline and Rebate Information:
408-630-2554
For a free Water-Wise Outdoor Survey, leave a
message at: 408-630-2000
Water Quality, Treatment &
Regulation Resources
American Water Works Association
AWWA.org
State Water Resources Control Board,
Division of Drinking Water
WaterBoards.CA.gov
United States Environmental Protection Agency
Water.epa.gov/Drink
San Francisco Public Utilities Commission,
Water Quality Bureau
SFWater.org
Valley Water
ValleyWater.org
Water Quality & Agriculture Information Center
nal.usda.gov/programs/waic
Additional Water Quality Information
Attention
Mahalaga ang impormasyong ito. Mangyaring ipasalin ito.
This report contains important information about
your drinking water. Translate it, or speak with
someone who understands it.
Attencion: Este informe contiene informacion muy
importante sobre su agua beber. Traduzcalo o hable con
alguien que lo entienda bien.
Chi tiet nal/..1llID...q n r a
Xin nho nglloi djch cho quy vj.
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~~fcl;-at~,~~cli"CTif I
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Published June 2025
2024
Water Quality
Consumer Confidence Report
CITY OF SANTA CLARA
1500 WARBURTON AVENUE
SANTA CLARA, CA 95050
The EPA and SWRCB prescribe regulations that limit the amounts of certain contaminants in water provided by public water systems to ensure its safety. U.S. Food and Drug Administration regulations and California law also establish contaminant limits in bottled water to provide protection for public health, though it’s tested less frequently than tap water.
Drinking water, including bottled water, may be expected to contain small amounts of contaminants; their presence doesn’t necessarily indicate that the water poses a health risk.
Naturally Occurring Drinking Water
Contaminants
Tap and bottled drinking water sources include rivers, lakes, streams, ponds, reservoirs, springs and wells. Travelling water dissolves naturally occurring minerals and, in some cases radioactive material, potentially picking up substances resulting from animal or human activity.
Naturally occurring source water contaminants may include:
• Microbials (viruses, bacteria) sewage treatment plants, septic systems, agricultural livestock operations or wildlife
• Inorganics (salts, metals): stormwater runoff, wastewater discharges, oil and gas production, mining, farming, naturally occurring
• Pesticides/herbicides: agriculture, stormwater runoff, landscaping • Organic chemicals: byproducts of synthetic and volatile organic chemical industrial processes and petroleum production or gas stations, stormwater runoff, agricultural and septic systems • Radioactive contaminants: naturally occurring or resulting from oil/gas production or mining activities
Arsenic and Perchlorate
Both Arsenic and Perchlorate were below their Public Health Goals, meaning there is no known or expected risk at their current levels in the City's drinking water.
Sources of arsenic occur from erosion of natural deposits, orchard runoff, and electronics and glass production wastes. Sources of perchlorate include rocket fuel, explosives and industrial uses and their resulting environmental contamination.
Lead
No Santa Clara water sources have exceeded the ACTION LEVEL for lead.
Lead levels in your home may be higher than others due to plumbing in your home’s original construction. Elevated lead levels can cause serious health problems, especially for pregnant women and young children.
Lead in drinking water comes from service line and home plumbing components. The City provides high quality drinking water, but cannot control materials used in your home’s plumbing. When water hasn’t been used for several hours, you can minimize potential lead exposure by:
1. Flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. (Use collected flushing water for cleaning, watering plants or running your garbage disposal.)
2. Using only cold water for drinking and cooking.
Concerned about lead in your water? Vi sit epa.gov/lead.
An initial lead service line inventory was completed in 2024 where more than 2,000 ser vice lines were inspected. No lead services were found during the inspections. A summary of the inventory can be found at SantaClaraCA.gov/WaterServiceLineInventory.
Nitrates in Groundwater Resources
Nitrate levels above 10 ppm in drinking water can interfere with the capacity of blood to carry oxygen in infants under six months old, pregnant women or those with specific enzyme deficiencies, resulting in serious illness. If you are pregnant or caring for an infant, consult your health care provider.
PFAS
Perfluoroalkyl and Polyfluoroalkyl substances, collectively known as PFAS, are a group of chemicals that have been widely used in industrial applications and consumer products such as carpets, clothing, furniture, fabrics, paper packaging for food, firefighting foams, and other materials including waterproof/stain resistant/nonstick cookware. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are two common types of PFAS. From 2019 to date, no PFAS compounds have been detected during the City's monitoring.
Hexavalent Chromium
Hexavalent Chromium, also known as Chromium-6, occurs naturally f rom the erosion of chromium deposits. It’ s used in various applications: paints, dyes, anticorrosion coatings and other industrial uses. As of October 1, 2024, the regulatory standard for Hexavalent Chromium is 10 ppb. Our 20 groundwater wells were tested for Hexavalent Chromium and were all found to be below 10 ppb.
Contaminant Regulations SFPUC Water: Tested for
Cryptosporidium & Giardia
Monthly (or more frequent) tests of SFPUC source and treated waters occasionally show very low levels of Cryptosporidium and Giardia in water serving the East Bay, South Bay and San Francisco Peninsula.
Cryptosporidiosis, an intestinal tract disease brought on by a parasitic microbe called Cryptosporidium, transmits through contaminated water, food or direct contact with human or animal waste. Giardia is caused by a different parasitic organism, but also causes symptoms similar to flu.
Symptoms usually last about two weeks for those with normal immune systems. Immuno-compromised people, infants, small children and the elderly are at greater risk of developing life-threatening illness.
Guidance from the California Department of Public Health and County health agencies recommend that people with serious immune problems consult their health care providers about preventing Cryptosporidium and Giardia infection. They may choose to bring drinking water to a rolling boil for at least one minute as an extra precaution.
Cryptosporidiosis and Giardiasis information and guidance:
• Santa Clara County Department of Environmental Health:
408-918-3400
Some Santa Clara Water is Fluoridated
Fluoridation adjusts naturally occurring fluoride in drinking water to the ideal level for protecting your teeth. Water purchased by the City from the SFPUC is fluoridated, while water from Valley Water is not.
If you’re in zip code 95054, you receive fluoridated water from the SFPUC that may be blended with unfluoridated well water. The area receiving a blend of water from both SFPUC and City wells are shown on the source water map included in this report. The majority of Santa Clara will continue to receive water without added fluoride. Contact your health care provider with any dental fluorosis concerns.
For more information, visit cdc.gov/fluoridation.
Leaks Sneak Up!
The EPA found that one in ten homes has a leak that wastes 90 gallons of water or more per day! Be diligent in checking for leaks in your home and landscape. Visit SantaClaraCA.gov/FixALeak for leak detection tips and to learn how the City can help.
Making Conservation A California Way
of Life
Last year, statewide rainfall topped 100% of average; now Moderate to Extreme drought conditions prevail in Southern California, while Abnormally Dry conditions threaten us. At our rainy season’s end, Santa Clara County rainfall year totaled just 68% of average. The State recognizes the ongoing drought reality:
• Making Conservation A California Way of Life regulations took effect statewide January 1.
• Urban Water Use Objective calls for a reduction to 47 gallons per capita per day from now until 2030.
• A drought emergency measure now permanently bans drinking water for irrigating non-functional turf at commercial, industrial, institutional (CII) and HOA properties with AB 1572, phasing in 2027.
Conservation remains critical to protect our drinking water supplies. Rain or shine, do your part to maximize water resources using free conservation devices and generous landscape rebates:
SantaClaraCA.gov/SaveOurWater.
Water & Sewer Utilities
1500 Warburton Ave.
Santa Clara, CA 95050
8 a.m.–5 p.m., Mon–Fri
408-615-2000, including emergencies
[email protected]
After-Hours Water Emergencies
408-615-5640
Water Billing Questions
408-615-2300
Water Quality Report Questions
Wendy Kwong
408-615-2000
[email protected]
Public Input
Provide input on decisions that affect drinking water
quality to Santa Clara City Council at a Council
meeting or in advance:
408-615-2250
[email protected]
A list of all City Council meetings, agenda items &
study sessions can be viewed on the City website at
SantaClara.Legistar.com/Calendar.aspx
Water Quality, Treatment &
Regulation Resources
American Water Works Association
AWWA.org
State Water Resources Control Board,
Division of Drinking Water
WaterBoards.CA.gov
United States Environmental Protection Agency
Water.epa.gov/Drink
San Francisco Public Utilities Commission,
Water Quality Bureau
SFWater.org
Valley Water
ValleyWater.org
Additional Water Quality Information
Attention
Mahalaga ang impormasyong ito. Mangyaring ipasalin ito.
This report contains important information about
your drinking water. Translate it, or speak with
someone who understands it.
Attencion: Este informe contiene informacion muy
importante sobre su agua beber. Traduzcalo o hable con
alguien que lo entienda bien.
PRSRT STD
US Postage
PAID
San Jose, CA
Permit #959
Naturally Clean Tap
Water Sources
Together, they provide an average of 15 million gallons of water per day to Santa Clara. Valley Water serves primarily the south-west portion of the City. SFPUC water typically serves the area north of Highway 101. The remaining water is pumped from the City’s system of 20 active wells serving the rest of Santa Clara. The map shows the general areas served by each source.
Tested much more frequently than bottled water, Santa Clara’s tap water undergoes rigorous, regular laboratory analysis and monitoring for over 100 potential contaminants and dozens of other parameters to ensure our drinking water meets Federal and State standards for health. Each week, water is collected from 34 sample stations throughout the City and sent to State-certified laboratories for testing.
We take pride in
delivering
high-quality
drinking water
This Consumer Confidence Report provides facts
and perspectives you need to make an informed
evaluation of your tap water. It contains water quality monitoring results for calendar year 2024 and
answers the most common customer questions.
The most frequently asked question we hear:
"Is our tap water safe to drink?" Yes! Our drinking
water quality is carefully regulated by the Federal
Government with the Safe Drinking Water Act,
requiring the United States Environmental Protection
Agency (EPA) to establish uniform standards enforced
by the State Water Resources Control Board (SWRCB),
Division of Drinking Water.
The 2024 Water Quality Report is prepared according
to the Safe Drinking Water Act requirements and
State regulations. Only constituents that were
detected in at least one water source appear in the
water quality table. As required by the State, we also
provide additional information for certain constituents though the water meets all enforceable drinking water
standards.
PRIMARY STANDARDS are designed to protect
public health, specifying limits called Maximum
Contaminant Levels (MCLs) for substances in
water that may be harmful to humans or affect
health if consumed in large quantities.
SECONDARY STANDARDS are qualities such as
color, taste and odor, specifying limits for
substances that may affect consumer acceptance of
the water.
The State allows us to monitor some contaminants
less than once per year since their concentrations
don’t change frequently. Due to regulatory monitoring
schedules, some data can be more than one year old.
For information, guidance and potential health effects
in English and Spanish, call:
EPA Safe Drinking Water Hotline: 1-800-426-4791
Guidance for People With
Compromised Immune
Systems
Some people may be more vulnerable to contaminants
in drinking water than the general population. Those
with cancer undergoing chemotherapy, with HIV/
AIDS or other immune system disorders, who have
undergone organ transplants, and some elderly,
infants and other immuno-compromised people can
be particularly at risk from infections and should seek advice about drinking water from their health care
providers.
Share this Water Quality Report with all people who
drink City tap water, especially if they may not have
received this notice directly.
This Water Quality Report is available online at
SantaClaraCA.gov/WaterQualityReport. Post it
in a public place or distribute paper copies by
hand or mail.
Free paper copies of the 2024 Water Quality Consumer
Confidence Report are available at:
• City Hall
• City Libraries
• Santa Clara Senior Center
• Community Recreation Center
• By request: [email protected]
or 408-615-2000
Water System
Improvements
The City performed several capital improvement
projects to maintain a high level of service and
provide quality potable water to our customers.
2024’s City Water Main Replacement Program
upgraded 12,000 linear feet (LF) of aging water main,
exceeding the annual replacement goal of 10,000 LF.
Replacement mains were up-sized to a standard 8-inch
size and replaced with new zinc-coated, ductile iron
mains. The replacement water mains improve water
quality and system resilience.
Well Rehabilitation
The City completed three well rehabilitation projects
in 2024 to improve efficiency and reliability: Well 18
across from Bowers Park, Well 23 by Millikan Basics+
Elementary and Well 34 near Northside Library.
The rehabilitation included replacement of the
existing pumps and motors, plus well cleaning and
redevelopment. Well 23 had been inactive since 2017.
All three wells are currently in service.
Cross-Connection
Control
The SWRCB adopted the Cross-Connection Policy
Control Handbook (CCCPH) July 1, 2024. The CCCPH
aims to protect public health by establishing standards to ensure a public water system’s drinking water
distribution system will not be subject to the backflow of liquids, gases or other substances. The standards
apply statewide as defined in California’s Health and
Safety Code (CHSC, section 116275 (h)); compliance
is mandatory.
Water & Sewer Utilities’ Compliance Division
administers the City’s cross-connection
control program. Visit SantaClaraCA.gov/
CrossConnectionControl for information.
Santa Clara's three water sources are used interchangeably or blended:
1. Protected groundwater wells within the City
2. Local reservoirs, rivers feeding the Sacramento Delta and others from Valley Water, our local water wholesaler
3. Snowmelt from the Sierra Nevada Mountains via the
San Francisco Public Utilities Commission (SFPUC) Hetch Hetchy System
Flushing water mains provides the highest water quality possible.
Santa Clara,
California
Blend of SFPUC
Hetch Hetchy
System and
Groundwater
a
Blend of Valley
Water Treated
Surface Water
and Groundwater
c
City of
Santa Clara
Groundwater
b
Source water
boundaries are
approximate
Source Water Information
City Groundwater Wells
Most of our water is pumped from the City’s system of deep wells. Well water is pulled up from aquifers 500 to 900 feet deep. Replenished by rainwater that infiltrates down from the land surface, aquifers are waterfilled spaces deep in the ground that collect rain naturally filtered through layers of sand, gravel, and silt.
SFPUC System
The City purchases water from the SFPUC, which is exempt from Federal and State filtration requirements, but receives the following treatments to meet all drinking water standards:
• Disinfection using ultraviolet light and chlorine
• pH adjustment for optimum corrosion control
• Fluoridation for dental health
• Chloramination to maintain disinfectant residual &
minimize the formation of regulated disinfection
byproducts
Valley Water
Valley Water provides water to Santa Clara from the Rinconada Water Treatment Plant, which processes water both sourced locally from Calero Reservoir and imported from the
Sacramento-San Joaquin Delta watershed.
Treatment includes:
• Filtration with anthracite coal and sand
• Disinfection using chlorine and chloramine
Visit the City’s Water Quality webpage for more information:
SantaClaraCA.gov/WaterQuality
This Water Quality Consumer
Confidence Report Details:
• Water sources and their
distribution.
• Federal and State standards that
drinking water must meet.
• Specific standards and
contaminants for which each of
our water sources is monitored
and tested.
• Required information explaining
why certain contaminants are
monitored.
Since the City’s first water service in
1895, reliably serving high-quality
drinking water has been the top priority
of Water & Sewer Utilities. With turn-
of-the-tap convenience, Santa Clarans
enjoy fresh, clean drinking water at
about 1¢ per gallon.
We encourage the public to
hydrate locally. Take full, cost-
effective advantage of California-
sourced drinking water, pure and
uncompromised by questionable plastic
packaging.
The Drinking Water Source Assessment
and Protection (DWSAP) Program,
completed and submitted to the
SWRCB in 2002, is available at the
Water & Sewer Utilities Office at City
Hall. You may request a summary by
calling 408-615-2000 or by emailing
watercompliance@SantaClaraCA.
gov.
UNIT MCL State PHG/
Fed MCLG
Analysis for
CSC WELL WATER
Analysis for
VALLEY WATER
Analysis for
SFPUC Common Sources
Range Average Range Average Range Average
Primary Standards For Source Water Sampling [highest running average]
MICROBIOLOGICAL
Giardia lamblia cyst/L TT 0 NA NA NA NA 0 - 0.06 0.02 naturally present in environment
RADIOACTIVITY
Gross Alpha pCi/L 15 (0) NA NA 3.3 3.3 ND ND erosion of natural deposits Uranium pCi/L 20 0.43 NA NA 1.3 1.3 ND ND erosion of natural deposits
INORGANIC CHEMICAL
Arsenic PPB 10 0.004 ND - 2.2 ND ND ND ND ND erosion of natural deposits/industrial wastes Barium PPM 1 2 ND - 0.2 0.14 ND ND ND ND erosion of natural deposits/oil drilling Fluoride PPM 2 1 ND - 0.2 0.14 ND - 0.11 ND 0.5 - 0.8 0.7 (1) water additive/erosion of natural deposits Hexavalent Chromium PPB 10 0.02 ND - 4.3 1.9 ND ND ND - 0.1 0.1 natural deposit leaching Nitrate (as Nitrogen) PPM 10 10 ND - 5.9 3.3 ND - 0.7 ND ND - 0.4 ND erosion of natural deposits/runoff/leaching Perchlorate PPB 6 1 ND - 1.1 ND ND ND ND ND environmental contamination
VOLATILE ORGANIC COMPOUND
Toluene PPB 150 150 ND - 4.3 0.6 ND ND ND ND petroleum or chemical discharges Secondary Standards: Consumer Acceptance Contaminent Levels Aluminum (2) PPB 200 600 ND - 90 ND ND ND ND - 59 ND
erosion of natural deposits; some surface water
treatment residue
Chloride PPM 500 NA 19 - 55 39 47 - 53 50 < 3 - 9.9 4.9 runoff/natural deposit leaching/seawater Color UNITS 15 NA ND - 10 3 ND - 3 2 < 5 < 5 naturally occuring organic material Iron PPB 300 NA ND- 280 130 < 20 < 20 < 6 - 41 20 natural deposit leaching/industrial wastes Odor UNITS 3 NA ND - 1 ND 1.4 - 2.0 1.6 ND ND naturally occuring organic material Manganese PPB 50 NA ND - 23 5 < 1.0 < 1.0 < 2 - 2.7 < 2 natural deposit leaching Specific Conductance uS/cm 1600 NA 465 - 718 591 414 - 522 466 31- 317 174 substances that form ions when in water/
seawater intrusion
Sulfate PPM 500 NA 25 - 58 42 57 - 80 66 1 - 41 21 runoff/natural deposit leaching/industrial wastes Total Dissolved Solids PPM 1000 NA 272 - 428 356 238 - 298 268 24 - 169 97 runoff/natural deposit leaching Turbidity NTU 5 NA 0.12 - 5.8 1.06 0.02 - 0.30 0.04 0.1 - 0.4 0.2 soil runoff Consumer Information
pH UNITS NS NS 7.6 - 7.8 7.7 7.5 - 8.0 7.7 NA NA
Alkalinity (as CaCO 3) PPM NS NS 159 - 246 202 68 - 87 77 7.4 - 120 56 Bicarbonate Alkalinity (as HCO 3) PPM NS NS NA NA 82 - 106 94 ND ND Boron PPB NS NS NA NA 114- 151 133 23 - 65 44
Calcium (as Ca) PPM NS NS 45 - 88 67 19 - 28 23 3.2 - 28 15 Chlorate (3) PPB NS NS NA NA NA NA 24 - 597 134
Hardness PPM NS NS 170 - 330 246 93 - 133 111 8.4 - 106 57 Lithium PPB NS NS NA NA NA NA < 2 - 4 2
Magnesium PPM NS NS 14 - 27 20 11-16 13 0.2 - 9.5 4.9
Phosphate PPM NS NS NA NA 0.96 - 1.16 1.07 ND ND
Potassium PPM NS NS 1 - 1.4 1.2 2.6 - 3.3 3.0 ND ND
Silica PPM NS NS NA NA 11 - 12 12 4.9 - 9.9 7.4
Sodium PPM NS NS 22 - 44 32 45 - 49 47 3.1 - 24 13
Temperature °C NS NS 9.9 - 35.8 19.3 13.9 - 21.6 18 NA NA Tot
al Organic Carbon (4) PPM NS NS NA NA 1.2 - 2.0 1.6 1.1 - 1.8 1.5 Vanadium PPB NS NS NA NA 1 - 2 2 NA NA
Primary Standards As Measured In City Of Santa Clara Distribution System UNITS MCL State MCL Range Average Common Sources
MICROBIOLOGICAL
Total Coliform % pos (+) 5.0% 5.0% 0 - 1.4% < 5.0% naturally present in environment Fecal Coliform and E.coli (5) # of pos (+) 0 0 0 0 human and animal fecal waste
DISINFECTION BYPRODUCTS, RESIDUALS, PRECURSORS
Trihalomethanes PPB 80 NA ND - 54.0 [56.0] byproduct of drinking water disinfection Haloacetic Acids PPB 60 NA ND - 46.4 [34.9] byproduct of drinking water disinfection Chlorine residual PPM 4 4 0.0 - 3.4 0.8 drinking water disinfectant INORGANIC CHEMICAL as measured at 52 Residential Taps in 2022:
Copper PPM AL = 1.3 0.3 90th percentile = 0.47 ppm Number Exceeded = 0 corrosion of plumbing systems Lead PPB AL = 15 0.2 90th percentile = ND Number Exceeded = 0 corrosion of plumbing systems SCHOOLS REQUESTING LEAD TESTING IN 2018: 33 Schools (172 samples taken) Lead PPB AL = 15 0.2 90th percentile = ND Number Exceeded = 1 (6) corrosion of plumbing systems Unregulated Contaminants As Measured In City Of Santa Clara Distribution System UNITS Notification Level Range Average
Lithium PPB NA ND - 10 ND
Definitions
DISINFECTION BYPRODUCTS = chemical
byproducts of disinfection
DISTRIBUTION SYSTEM = drinking water delivery
system
HARDNESS = the sum of polyvalent cations
present in the water, generally magnesium and
calcium. The cations are usually naturally occurring.
MAXIMUM CONTAMINANT LEVEL (MCL) = The
highest level of a contaminant 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 CONTAMINANT LEVEL GOAL (MCLG)
= The level of a contaminant in drinking water
below which there is no known or expected risk to
health. MCLGs are set by the U.S. EPA.
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.
NA = not applicable or available
ND = not detected
NS = no standard
NTU = Nephelometric Turbidity Unit. Turbidity is a
measure of the cloudiness of the water. We monitor
it because it is a good indicator of water quality.
pCi/L = picocuries per liter (a measure of
radioactivity)
PPB = Parts Per Billion (µg/L)
PPM = Parts Per Million (mg/L)
PRIMARY DRINKING WATER STANDARDS
(PDWS) = MCLs and MRDLs for contaminants
that affect health along with their monitoring
and reporting requirements, and water treatment
requirements.
PUBLIC HEALTH GOAL (PHG) = The level of a
contaminant in drinking water below which there is
no known or expected risk to health. PHGs are set
by the California EPA.
REGULATORY ACTION LEVEL (AL) =
The concentration of a contaminant which, if
exceeded, triggers treatment or other requirements
that a water system must follow.
RESIDENTIAL TAPS = household faucets used for
lead and copper sampling
SECONDARY STANDARDS = secondary
MCLs are set to protect the aesthetics of drinking
water
SODIUM = refers to the salt present in the water
and is generally naturally occurring.
TREATMENT TECHNIQUE (TT) = A required process
intended to reduce the level of a contaminant in
drinking water.
UNREGULATED CONTAMINANTS = Unregulated
contaminant monitoring helps EPA and SWRCB to
determine where certain contaminants occur and
whether the contaminants need to be regulated.
Every four years, the EPA updates the list of
unregulated contaminants to monitor.
uS/cm = microSiemens per centimeter
Notes
(1) Natural fluoride in the Hetch Hetchy water was
ND. The fluoride level in raw water ranged from ND
to 0.8 ppm with an average of 0.2 ppm.
(2) Aluminum also has a primary MCL of 1,000 ppb.
(3) The detected chlorate in the treated water is a
degradation product of sodium hypochlorite used
by the San Francisco Regional Water System for
water disinfection.
(4) The range and average values of the total
organic carbon were from operational monitoring
results at Tesla Treatment Facilities.
(5) The MCL was changed to E. coli starting on July
1, 2021 when the State Revised Total Coliform Rule
became effective.
(6) 2018 sampling result for John Sutter Elementary
was 26ppb. Repeat sampling following plumbing
repairs was non-detect for lead.
City of Santa Clara
Water Quality Table
All Santa Clara
water sources
meet or exceed
Federal and
State standards.
Santa Clara Drinking Water Sources
Naturally Clean Tap
Water Sources
Together, they provide an average of 15 million gallons of water per day to Santa Clara. Valley Water serves primarily the south-west portion of the City. SFPUC water typically serves the area north of Highway 101. The remaining water is pumped from the City’s system of 20 active wells serving the rest of Santa Clara. The map shows the general areas served by each source.
Tested much more frequently than bottled water, Santa Clara’s tap water undergoes rigorous, regular laboratory analysis and monitoring for over 100 potential contaminants and dozens of other parameters to ensure our drinking water meets Federal and State standards for health. Each week, water is collected from 34 sample stations throughout the City and sent to State-certified laboratories for testing.
We take pride in
delivering
high-quality
drinking water
This Consumer Confidence Report provides facts
and perspectives you need to make an informed
evaluation of your tap water. It contains water quality monitoring results for calendar year 2024 and
answers the most common customer questions.
The most frequently asked question we hear:
"Is our tap water safe to drink?" Yes! Our drinking
water quality is carefully regulated by the Federal
Government with the Safe Drinking Water Act,
requiring the United States Environmental Protection
Agency (EPA) to establish uniform standards enforced
by the State Water Resources Control Board (SWRCB),
Division of Drinking Water.
The 2024 Water Quality Report is prepared according
to the Safe Drinking Water Act requirements and
State regulations. Only constituents that were
detected in at least one water source appear in the
water quality table. As required by the State, we also
provide additional information for certain constituents though the water meets all enforceable drinking water
standards.
PRIMARY STANDARDS are designed to protect
public health, specifying limits called Maximum
Contaminant Levels (MCLs) for substances in
water that may be harmful to humans or affect
health if consumed in large quantities.
SECONDARY STANDARDS are qualities such as
color, taste and odor, specifying limits for
substances that may affect consumer acceptance of
the water.
The State allows us to monitor some contaminants
less than once per year since their concentrations
don’t change frequently. Due to regulatory monitoring
schedules, some data can be more than one year old.
For information, guidance and potential health effects
in English and Spanish, call:
EPA Safe Drinking Water Hotline: 1-800-426-4791
Guidance for People With
Compromised Immune
Systems
Some people may be more vulnerable to contaminants
in drinking water than the general population. Those
with cancer undergoing chemotherapy, with HIV/
AIDS or other immune system disorders, who have
undergone organ transplants, and some elderly,
infants and other immuno-compromised people can
be particularly at risk from infections and should seek advice about drinking water from their health care
providers.
Share this Water Quality Report with all people who
drink City tap water, especially if they may not have
received this notice directly.
This Water Quality Report is available online at
SantaClaraCA.gov/WaterQualityReport. Post it
in a public place or distribute paper copies by
hand or mail.
Free paper copies of the 2024 Water Quality Consumer
Confidence Report are available at:
• City Hall
• City Libraries
• Santa Clara Senior Center
• Community Recreation Center
• By request: [email protected]
or 408-615-2000
Water System
Improvements
The City performed several capital improvement
projects to maintain a high level of service and
provide quality potable water to our customers.
2024’s City Water Main Replacement Program
upgraded 12,000 linear feet (LF) of aging water main,
exceeding the annual replacement goal of 10,000 LF.
Replacement mains were up-sized to a standard 8-inch
size and replaced with new zinc-coated, ductile iron
mains. The replacement water mains improve water
quality and system resilience.
Well Rehabilitation
The City completed three well rehabilitation projects
in 2024 to improve efficiency and reliability: Well 18
across from Bowers Park, Well 23 by Millikan Basics+
Elementary and Well 34 near Northside Library.
The rehabilitation included replacement of the
existing pumps and motors, plus well cleaning and
redevelopment. Well 23 had been inactive since 2017.
All three wells are currently in service.
Cross-Connection
Control
The SWRCB adopted the Cross-Connection Policy
Control Handbook (CCCPH) July 1, 2024. The CCCPH
aims to protect public health by establishing standards to ensure a public water system’s drinking water
distribution system will not be subject to the backflow of liquids, gases or other substances. The standards
apply statewide as defined in California’s Health and
Safety Code (CHSC, section 116275 (h)); compliance
is mandatory.
Water & Sewer Utilities’ Compliance Division
administers the City’s cross-connection
control program. Visit SantaClaraCA.gov/
CrossConnectionControl for information.
Santa Clara's three water sources are used interchangeably or blended:
1. Protected groundwater wells within the City
2. Local reservoirs, rivers feeding the Sacramento Delta and others from Valley Water, our local water wholesaler
3. Snowmelt from the Sierra Nevada Mountains via the
San Francisco Public Utilities Commission (SFPUC) Hetch Hetchy System
Flushing water mains provides the highest water quality possible.
Santa Clara,
California
Blend of SFPUC
Hetch Hetchy
System and
Groundwater
a
Blend of Valley
Water Treated
Surface Water
and Groundwater
c
City of
Santa Clara
Groundwater
b
Source water
boundaries are
approximate
Source Water Information
City Groundwater Wells
Most of our water is pumped from the City’s system of deep wells. Well water is pulled up from aquifers 500 to 900 feet deep. Replenished by rainwater that infiltrates down from the land surface, aquifers are waterfilled spaces deep in the ground that collect rain naturally filtered through layers of sand, gravel, and silt.
SFPUC System
The City purchases water from the SFPUC, which is exempt from Federal and State filtration requirements, but receives the following treatments to meet all drinking water standards:
• Disinfection using ultraviolet light and chlorine
• pH adjustment for optimum corrosion control
• Fluoridation for dental health
• Chloramination to maintain disinfectant residual &
minimize the formation of regulated disinfection
byproducts
Valley Water
Valley Water provides water to Santa Clara from the Rinconada Water Treatment Plant, which processes water both sourced locally from Calero Reservoir and imported from the
Sacramento-San Joaquin Delta watershed.
Treatment includes:
• Filtration with anthracite coal and sand
• Disinfection using chlorine and chloramine
Visit the City’s Water Quality webpage for more information:
SantaClaraCA.gov/WaterQuality
This Water Quality Consumer
Confidence Report Details:
• Water sources and their
distribution.
• Federal and State standards that
drinking water must meet.
• Specific standards and
contaminants for which each of
our water sources is monitored
and tested.
• Required information explaining
why certain contaminants are
monitored.
Since the City’s first water service in
1895, reliably serving high-quality
drinking water has been the top priority
of Water & Sewer Utilities. With turn-
of-the-tap convenience, Santa Clarans
enjoy fresh, clean drinking water at
about 1¢ per gallon.
We encourage the public to
hydrate locally. Take full, cost-
effective advantage of California-
sourced drinking water, pure and
uncompromised by questionable plastic
packaging.
The Drinking Water Source Assessment
and Protection (DWSAP) Program,
completed and submitted to the
SWRCB in 2002, is available at the
Water & Sewer Utilities Office at City
Hall. You may request a summary by
calling 408-615-2000 or by emailing
watercompliance@SantaClaraCA.
gov.
UNIT MCL State PHG/
Fed MCLG
Analysis for
CSC WELL WATER
Analysis for
VALLEY WATER
Analysis for
SFPUC Common Sources
Range Average Range Average Range Average
Primary Standards For Source Water Sampling [highest running average]
MICROBIOLOGICAL
Giardia lamblia cyst/L TT 0 NA NA NA NA 0 - 0.06 0.02 naturally present in environment
RADIOACTIVITY
Gross Alpha pCi/L 15 (0) NA NA 3.3 3.3 ND ND erosion of natural deposits Uranium pCi/L 20 0.43 NA NA 1.3 1.3 ND ND erosion of natural deposits
INORGANIC CHEMICAL
Arsenic PPB 10 0.004 ND - 2.2 ND ND ND ND ND erosion of natural deposits/industrial wastes Barium PPM 1 2 ND - 0.2 0.14 ND ND ND ND erosion of natural deposits/oil drilling Fluoride PPM 2 1 ND - 0.2 0.14 ND - 0.11 ND 0.5 - 0.8 0.7 (1) water additive/erosion of natural deposits Hexavalent Chromium PPB 10 0.02 ND - 4.3 1.9 ND ND ND - 0.1 0.1 natural deposit leaching Nitrate (as Nitrogen) PPM 10 10 ND - 5.9 3.3 ND - 0.7 ND ND - 0.4 ND erosion of natural deposits/runoff/leaching Perchlorate PPB 6 1 ND - 1.1 ND ND ND ND ND environmental contamination
VOLATILE ORGANIC COMPOUND
Toluene PPB 150 150 ND - 4.3 0.6 ND ND ND ND petroleum or chemical discharges Secondary Standards: Consumer Acceptance Contaminent Levels Aluminum (2) PPB 200 600 ND - 90 ND ND ND ND - 59 ND
erosion of natural deposits; some surface water
treatment residue
Chloride PPM 500 NA 19 - 55 39 47 - 53 50 < 3 - 9.9 4.9 runoff/natural deposit leaching/seawater Color UNITS 15 NA ND - 10 3 ND - 3 2 < 5 < 5 naturally occuring organic material Iron PPB 300 NA ND- 280 130 < 20 < 20 < 6 - 41 20 natural deposit leaching/industrial wastes Odor UNITS 3 NA ND - 1 ND 1.4 - 2.0 1.6 ND ND naturally occuring organic material Manganese PPB 50 NA ND - 23 5 < 1.0 < 1.0 < 2 - 2.7 < 2 natural deposit leaching Specific Conductance uS/cm 1600 NA 465 - 718 591 414 - 522 466 31- 317 174 substances that form ions when in water/
seawater intrusion
Sulfate PPM 500 NA 25 - 58 42 57 - 80 66 1 - 41 21 runoff/natural deposit leaching/industrial wastes Total Dissolved Solids PPM 1000 NA 272 - 428 356 238 - 298 268 24 - 169 97 runoff/natural deposit leaching Turbidity NTU 5 NA 0.12 - 5.8 1.06 0.02 - 0.30 0.04 0.1 - 0.4 0.2 soil runoff Consumer Information
pH UNITS NS NS 7.6 - 7.8 7.7 7.5 - 8.0 7.7 NA NA
Alkalinity (as CaCO 3) PPM NS NS 159 - 246 202 68 - 87 77 7.4 - 120 56 Bicarbonate Alkalinity (as HCO 3) PPM NS NS NA NA 82 - 106 94 ND ND Boron PPB NS NS NA NA 114- 151 133 23 - 65 44
Calcium (as Ca) PPM NS NS 45 - 88 67 19 - 28 23 3.2 - 28 15 Chlorate (3) PPB NS NS NA NA NA NA 24 - 597 134
Hardness PPM NS NS 170 - 330 246 93 - 133 111 8.4 - 106 57 Lithium PPB NS NS NA NA NA NA < 2 - 4 2
Magnesium PPM NS NS 14 - 27 20 11-16 13 0.2 - 9.5 4.9
Phosphate PPM NS NS NA NA 0.96 - 1.16 1.07 ND ND
Potassium PPM NS NS 1 - 1.4 1.2 2.6 - 3.3 3.0 ND ND
Silica PPM NS NS NA NA 11 - 12 12 4.9 - 9.9 7.4
Sodium PPM NS NS 22 - 44 32 45 - 49 47 3.1 - 24 13
Temperature °C NS NS 9.9 - 35.8 19.3 13.9 - 21.6 18 NA NA Total Organic Carbon (4) PPM NS NS NA NA 1.2 - 2.0 1.6 1.1 - 1.8 1.5 Vanadium PPB NS NS NA NA 1 - 2 2 NA NA
Primary Standards As Measured In City Of Santa Clara Distribution System UNITS MCL State MCL Range Average Common Sources
MICROBIOLOGICAL
Total Coliform % pos (+) 5.0% 5.0% 0 - 1.4% < 5.0% naturally present in environment Fecal Coliform and E.coli (5) # of pos (+) 0 0 0 0 human and animal fecal waste
DISINFECTION BYPRODUCTS, RESIDUALS, PRECURSORS
Trihalomethanes PPB 80 NA ND - 54.0 [56.0] byproduct of drinking water disinfection Haloacetic Acids PPB 60 NA ND - 46.4 [34.9] byproduct of drinking water disinfection Chlorine residual PPM 4 4 0.0 - 3.4 0.8 drinking water disinfectant INORGANIC CHEMICAL as measured at 52 Residential Taps in 2022:
Copper PPM AL = 1.3 0.3 90th percentile = 0.47 ppm Number Exceeded = 0 corrosion of plumbing systems Lead PPB AL = 15 0.2 90th percentile = ND Number Exceeded = 0 corrosion of plumbing systems SCHOOLS REQUESTING LEAD TESTING IN 2018: 33 Schools (172 samples taken) Lead PPB AL = 15 0.2 90th percentile = ND Number Exceeded = 1 (6) corrosion of plumbing systems Unregulated Contaminants As Measured In City Of Santa Clara Distribution System UNITS Notification Level Range Average
Lithium PPB NA ND - 10 ND
Definitions
DISINFECTION BYPRODUCTS = chemical
byproducts of disinfection
DISTRIBUTION SYSTEM = drinking water delivery
system
HARDNESS = the sum of polyvalent cations
present in the water, generally magnesium and
calcium. The cations are usually naturally occurring.
MAXIMUM CONTAMINANT LEVEL (MCL) = The
highest level of a contaminant 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 CONTAMINANT LEVEL GOAL (MCLG)
= The level of a contaminant in drinking water
below which there is no known or expected risk to
health. MCLGs are set by the U.S. EPA.
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.
NA = not applicable or available
ND = not detected
NS = no standard
NTU = Nephelometric Turbidity Unit. Turbidity is a
measure of the cloudiness of the water. We monitor
it because it is a good indicator of water quality.
pCi/L = picocuries per liter (a measure of
radioactivity)
PPB = Parts Per Billion (µg/L)
PPM = Parts Per Million (mg/L)
PRIMARY DRINKING WATER STANDARDS
(PDWS) = MCLs and MRDLs for contaminants
that affect health along with their monitoring
and reporting requirements, and water treatment
requirements.
PUBLIC HEALTH GOAL (PHG) = The level of a
contaminant in drinking water below which there is
no known or expected risk to health. PHGs are set
by the California EPA.
REGULATORY ACTION LEVEL (AL) =
The concentration of a contaminant which, if
exceeded, triggers treatment or other requirements
that a water system must follow.
RESIDENTIAL TAPS = household faucets used for
lead and copper sampling
SECONDARY STANDARDS = secondary
MCLs are set to protect the aesthetics of drinking
water
SODIUM = refers to the salt present in the water
and is generally naturally occurring.
TREATMENT TECHNIQUE (TT) = A required process
intended to reduce the level of a contaminant in
drinking water.
UNREGULATED CONTAMINANTS = Unregulated
contaminant monitoring helps EPA and SWRCB to
determine where certain contaminants occur and
whether the contaminants need to be regulated.
Every four years, the EPA updates the list of
unregulated contaminants to monitor.
uS/cm = microSiemens per centimeter
Notes
(1) Natural fluoride in the Hetch Hetchy water was
ND. The fluoride level in raw water ranged from ND
to 0.8 ppm with an average of 0.2 ppm.
(2) Aluminum also has a primary MCL of 1,000 ppb.
(3) The detected chlorate in the treated water is a
degradation product of sodium hypochlorite used
by the San Francisco Regional Water System for
water disinfection.
(4) The range and average values of the total
organic carbon were from operational monitoring
results at Tesla Treatment Facilities.
(5) The MCL was changed to E. coli starting on July
1, 2021 when the State Revised Total Coliform Rule
became effective.
(6) 2018 sampling result for John Sutter Elementary
was 26ppb. Repeat sampling following plumbing
repairs was non-detect for lead.
City of Santa Clara
Water Quality Table
All Santa Clara
water sources
meet or exceed
Federal and
State standards.
Naturally Clean Tap
Water Sources
Together, they provide an average of 15 million gallons of water per day to Santa Clara. Valley Water serves primarily the south-west portion of the City. SFPUC water typically serves the area north of Highway 101. The remaining water is pumped from the City’s system of 20 active wells serving the rest of Santa Clara. The map shows the general areas served by each source.
Tested much more frequently than bottled water, Santa Clara’s tap water undergoes rigorous, regular laboratory analysis and monitoring for over 100 potential contaminants and dozens of other parameters to ensure our drinking water meets Federal and State standards for health. Each week, water is collected from 34 sample stations throughout the City and sent to State-certified laboratories for testing.
We take pride in
delivering
high-quality
drinking water
This Consumer Confidence Report provides facts
and perspectives you need to make an informed
evaluation of your tap water. It contains water quality monitoring results for calendar year 2024 and
answers the most common customer questions.
The most frequently asked question we hear:
"Is our tap water safe to drink?" Yes! Our drinking
water quality is carefully regulated by the Federal
Government with the Safe Drinking Water Act,
requiring the United States Environmental Protection
Agency (EPA) to establish uniform standards enforced
by the State Water Resources Control Board (SWRCB),
Division of Drinking Water.
The 2024 Water Quality Report is prepared according
to the Safe Drinking Water Act requirements and
State regulations. Only constituents that were
detected in at least one water source appear in the
water quality table. As required by the State, we also
provide additional information for certain constituents though the water meets all enforceable drinking water
standards.
PRIMARY STANDARDS are designed to protect
public health, specifying limits called Maximum
Contaminant Levels (MCLs) for substances in
water that may be harmful to humans or affect
health if consumed in large quantities.
SECONDARY STANDARDS are qualities such as
color, taste and odor, specifying limits for
substances that may affect consumer acceptance of
the water.
The State allows us to monitor some contaminants
less than once per year since their concentrations
don’t change frequently. Due to regulatory monitoring
schedules, some data can be more than one year old.
For information, guidance and potential health effects
in English and Spanish, call:
EPA Safe Drinking Water Hotline: 1-800-426-4791
Guidance for People With
Compromised Immune
Systems
Some people may be more vulnerable to contaminants
in drinking water than the general population. Those
with cancer undergoing chemotherapy, with HIV/
AIDS or other immune system disorders, who have
undergone organ transplants, and some elderly,
infants and other immuno-compromised people can
be particularly at risk from infections and should seek advice about drinking water from their health care
providers.
Share this Water Quality Report with all people who
drink City tap water, especially if they may not have
received this notice directly.
This Water Quality Report is available online at
SantaClaraCA.gov/WaterQualityReport. Post it
in a public place or distribute paper copies by
hand or mail.
Free paper copies of the 2024 Water Quality Consumer
Confidence Report are available at:
• City Hall
• City Libraries
• Santa Clara Senior Center
• Community Recreation Center
• By request: [email protected]
or 408-615-2000
Water System
Improvements
The City performed several capital improvement
projects to maintain a high level of service and
provide quality potable water to our customers.
2024’s City Water Main Replacement Program
upgraded 12,000 linear feet (LF) of aging water main,
exceeding the annual replacement goal of 10,000 LF.
Replacement mains were up-sized to a standard 8-inch
size and replaced with new zinc-coated, ductile iron
mains. The replacement water mains improve water
quality and system resilience.
Well Rehabilitation
The City completed three well rehabilitation projects
in 2024 to improve efficiency and reliability: Well 18
across from Bowers Park, Well 23 by Millikan Basics+
Elementary and Well 34 near Northside Library.
The rehabilitation included replacement of the
existing pumps and motors, plus well cleaning and
redevelopment. Well 23 had been inactive since 2017.
All three wells are currently in service.
Cross-Connection
Control
The SWRCB adopted the Cross-Connection Policy
Control Handbook (CCCPH) July 1, 2024. The CCCPH
aims to protect public health by establishing standards to ensure a public water system’s drinking water
distribution system will not be subject to the backflow of liquids, gases or other substances. The standards
apply statewide as defined in California’s Health and
Safety Code (CHSC, section 116275 (h)); compliance
is mandatory.
Water & Sewer Utilities’ Compliance Division
administers the City’s cross-connection
control program. Visit SantaClaraCA.gov/
CrossConnectionControl for information.
Santa Clara's three water sources are used interchangeably or blended:
1. Protected groundwater wells within the City
2. Local reservoirs, rivers feeding the Sacramento Delta and others from Valley Water, our local water wholesaler
3. Snowmelt from the Sierra Nevada Mountains via the
San Francisco Public Utilities Commission (SFPUC) Hetch Hetchy System
Flushing water mains provides the highest water quality possible.
Santa Clara,
California
Blend of SFPUC
Hetch Hetchy
System and
Groundwater
a
Blend of Valley
Water Treated
Surface Water
and Groundwater
c
City of
Santa Clara
Groundwater
b
Source water
boundaries are
approximate
Source Water Information
City Groundwater Wells
Most of our water is pumped from the City’s system of deep wells. Well water is pulled up from aquifers 500 to 900 feet deep. Replenished by rainwater that infiltrates down from the land surface, aquifers are waterfilled spaces deep in the ground that collect rain naturally filtered through layers of sand, gravel, and silt.
SFPUC System
The City purchases water from the SFPUC, which is exempt from Federal and State filtration requirements, but receives the following treatments to meet all drinking water standards:
• Disinfection using ultraviolet light and chlorine
• pH adjustment for optimum corrosion control
• Fluoridation for dental health
• Chloramination to maintain disinfectant residual &
minimize the formation of regulated disinfection
byproducts
Valley Water
Valley Water provides water to Santa Clara from the Rinconada Water Treatment Plant, which processes water both sourced locally from Calero Reservoir and imported from the
Sacramento-San Joaquin Delta watershed.
Treatment includes:
• Filtration with anthracite coal and sand
• Disinfection using chlorine and chloramine
Visit the City’s Water Quality webpage for more information:
SantaClaraCA.gov/WaterQuality
This Water Quality Consumer
Confidence Report Details:
• Water sources and their
distribution.
• Federal and State standards that
drinking water must meet.
• Specific standards and
contaminants for which each of
our water sources is monitored
and tested.
• Required information explaining
why certain contaminants are
monitored.
Since the City’s first water service in
1895, reliably serving high-quality
drinking water has been the top priority
of Water & Sewer Utilities. With turn-
of-the-tap convenience, Santa Clarans
enjoy fresh, clean drinking water at
about 1¢ per gallon.
We encourage the public to
hydrate locally. Take full, cost-
effective advantage of California-
sourced drinking water, pure and
uncompromised by questionable plastic
packaging.
The Drinking Water Source Assessment
and Protection (DWSAP) Program,
completed and submitted to the
SWRCB in 2002, is available at the
Water & Sewer Utilities Office at City
Hall. You may request a summary by
calling 408-615-2000 or by emailing
watercompliance@SantaClaraCA.
gov.
UNIT MCL State PHG/
Fed MCLG
Analysis for
CSC WELL WATER
Analysis for
VALLEY WATER
Analysis for
SFPUC Common Sources
Range Average Range Average Range Average
Primary Standards For Source Water Sampling [highest running average]
MICROBIOLOGICAL
Giardia lamblia cyst/L TT 0 NA NA NA NA 0 - 0.06 0.02 naturally present in environment
RADIOACTIVITY
Gross Alpha pCi/L 15 (0) NA NA 3.3 3.3 ND ND erosion of natural deposits Uranium pCi/L 20 0.43 NA NA 1.3 1.3 ND ND erosion of natural deposits
INORGANIC CHEMICAL
Arsenic PPB 10 0.004 ND - 2.2 ND ND ND ND ND erosion of natural deposits/industrial wastes Barium PPM 1 2 ND - 0.2 0.14 ND ND ND ND erosion of natural deposits/oil drilling Fluoride PPM 2 1 ND - 0.2 0.14 ND - 0.11 ND 0.5 - 0.8 0.7 (1) water additive/erosion of natural deposits Hexavalent Chromium PPB 10 0.02 ND - 4.3 1.9 ND ND ND - 0.1 0.1 natural deposit leaching Nitrate (as Nitrogen) PPM 10 10 ND - 5.9 3.3 ND - 0.7 ND ND - 0.4 ND erosion of natural deposits/runoff/leaching Perchlorate PPB 6 1 ND - 1.1 ND ND ND ND ND environmental contamination
VOLATILE ORGANIC COMPOUND
Toluene PPB 150 150 ND - 4.3 0.6 ND ND ND ND petroleum or chemical discharges Secondary Standards: Consumer Acceptance Contaminent Levels Aluminum (2) PPB 200 600 ND - 90 ND ND ND ND - 59 ND
erosion of natural deposits; some surface water
treatment residue
Chloride PPM 500 NA 19 - 55 39 47 - 53 50 < 3 - 9.9 4.9 runoff/natural deposit leaching/seawater Color UNITS 15 NA ND - 10 3 ND - 3 2 < 5 < 5 naturally occuring organic material Iron PPB 300 NA ND- 280 130 < 20 < 20 < 6 - 41 20 natural deposit leaching/industrial wastes Odor UNITS 3 NA ND - 1 ND 1.4 - 2.0 1.6 ND ND naturally occuring organic material Manganese PPB 50 NA ND - 23 5 < 1.0 < 1.0 < 2 - 2.7 < 2 natural deposit leaching Specific Conductance uS/cm 1600 NA 465 - 718 591 414 - 522 466 31- 317 174 substances that form ions when in water/
seawater intrusion
Sulfate PPM 500 NA 25 - 58 42 57 - 80 66 1 - 41 21 runoff/natural deposit leaching/industrial wastes Total Dissolved Solids PPM 1000 NA 272 - 428 356 238 - 298 268 24 - 169 97 runoff/natural deposit leaching Turbidity NTU 5 NA 0.12 - 5.8 1.06 0.02 - 0.30 0.04 0.1 - 0.4 0.2 soil runoff Consumer Information
pH UNITS NS NS 7.6 - 7.8 7.7 7.5 - 8.0 7.7 NA NA
Alkalinity (as CaCO 3) PPM NS NS 159 - 246 202 68 - 87 77 7.4 - 120 56 Bicarbonate Alkalinity (as HCO 3) PPM NS NS NA NA 82 - 106 94 ND ND Boron PPB NS NS NA NA 114- 151 133 23 - 65 44
Calcium (as Ca) PPM NS NS 45 - 88 67 19 - 28 23 3.2 - 28 15 Chlorate (3) PPB NS NS NA NA NA NA 24 - 597 134
Hardness PPM NS NS 170 - 330 246 93 - 133 111 8.4 - 106 57 Lithium PPB NS NS NA NA NA NA < 2 - 4 2
Magnesium PPM NS NS 14 - 27 20 11-16 13 0.2 - 9.5 4.9
Phosphate PPM NS NS NA NA 0.96 - 1.16 1.07 ND ND
Potassium PPM NS NS 1 - 1.4 1.2 2.6 - 3.3 3.0 ND ND
Silica PPM NS NS NA NA 11 - 12 12 4.9 - 9.9 7.4
Sodium PPM NS NS 22 - 44 32 45 - 49 47 3.1 - 24 13
Temperature °C NS NS 9.9 - 35.8 19.3 13.9 - 21.6 18 NA NA Total Organic Carbon (4) PPM NS NS NA NA 1.2 - 2.0 1.6 1.1 - 1.8 1.5 Vanadium PPB NS NS NA NA 1 - 2 2 NA NA
Primary Standards As Measured In City Of Santa Clara Distribution System UNITS MCL State MCL Range Average Common Sources
MICROBIOLOGICAL
Total Coliform % pos (+) 5.0% 5.0% 0 - 1.4% < 5.0% naturally present in environment Fecal Coliform and E.coli (5) # of pos (+) 0 0 0 0 human and animal fecal waste
DISINFECTION BYPRODUCTS, RESIDUALS, PRECURSORS
Trihalomethanes PPB 80 NA ND - 54.0 [56.0] byproduct of drinking water disinfection Haloacetic Acids PPB 60 NA ND - 46.4 [34.9] byproduct of drinking water disinfection Chlorine residual PPM 4 4 0.0 - 3.4 0.8 drinking water disinfectant INORGANIC CHEMICAL as measured at 52 Residential Taps in 2022:
Copper PPM AL = 1.3 0.3 90th percentile = 0.47 ppm Number Exceeded = 0 corrosion of plumbing systems Lead PPB AL = 15 0.2 90th percentile = ND Number Exceeded = 0 corrosion of plumbing systems SCHOOLS REQUESTING LEAD TESTING IN 2018: 33 Schools (172 samples taken) Lead PPB AL = 15 0.2 90th percentile = ND Number Exceeded = 1 (6) corrosion of plumbing systems Unregulated Contaminants As Measured In City Of Santa Clara Distribution System UNITS Notification Level Range Average
Lithium PPB NA ND - 10 ND
Definitions
DISINFECTION BYPRODUCTS = chemical
byproducts of disinfection
DISTRIBUTION SYSTEM = drinking water delivery
system
HARDNESS = the sum of polyvalent cations
present in the water, generally magnesium and
calcium. The cations are usually naturally occurring.
MAXIMUM CONTAMINANT LEVEL (MCL) = The
highest level of a contaminant 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 CONTAMINANT LEVEL GOAL (MCLG)
= The level of a contaminant in drinking water
below which there is no known or expected risk to
health. MCLGs are set by the U.S. EPA.
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.
NA = not applicable or available
ND = not detected
NS = no standard
NTU = Nephelometric Turbidity Unit. Turbidity is a
measure of the cloudiness of the water. We monitor
it because it is a good indicator of water quality.
pCi/L = picocuries per liter (a measure of
radioactivity)
PPB = Parts Per Billion (µg/L)
PPM = Parts Per Million (mg/L)
PRIMARY DRINKING WATER STANDARDS
(PDWS) = MCLs and MRDLs for contaminants
that affect health along with their monitoring
and reporting requirements, and water treatment
requirements.
PUBLIC HEALTH GOAL (PHG) = The level of a
contaminant in drinking water below which there is
no known or expected risk to health. PHGs are set
by the California EPA.
REGULATORY ACTION LEVEL (AL) =
The concentration of a contaminant which, if
exceeded, triggers treatment or other requirements
that a water system must follow.
RESIDENTIAL TAPS = household faucets used for
lead and copper sampling
SECONDARY STANDARDS = secondary
MCLs are set to protect the aesthetics of drinking
water
SODIUM = refers to the salt present in the water
and is generally naturally occurring.
TREATMENT TECHNIQUE (TT) = A required process
intended to reduce the level of a contaminant in
drinking water.
UNREGULATED CONTAMINANTS = Unregulated
contaminant monitoring helps EPA and SWRCB to
determine where certain contaminants occur and
whether the contaminants need to be regulated.
Every four years, the EPA updates the list of
unregulated contaminants to monitor.
uS/cm = microSiemens per centimeter
Notes
(1) Natural fluoride in the Hetch Hetchy water was
ND. The fluoride level in raw water ranged from ND
to 0.8 ppm with an average of 0.2 ppm.
(2) Aluminum also has a primary MCL of 1,000 ppb.
(3) The detected chlorate in the treated water is a
degradation product of sodium hypochlorite used
by the San Francisco Regional Water System for
water disinfection.
(4) The range and average values of the total
organic carbon were from operational monitoring
results at Tesla Treatment Facilities.
(5) The MCL was changed to E. coli starting on July
1, 2021 when the State Revised Total Coliform Rule
became effective.
(6) 2018 sampling result for John Sutter Elementary
was 26ppb. Repeat sampling following plumbing
repairs was non-detect for lead.
City of Santa Clara
Water Quality Table
All Santa Clara
water sources
meet or exceed
Federal and
State standards.
Published June 2025
2024
Water Quality
Consumer Confidence Report
CITY OF SANTA CLARA
1500 WARBURTON AVENUE
SANTA CLARA, CA 95050
The EPA and SWRCB prescribe regulations that limit the amounts of certain contaminants in water provided by public water systems to ensure its safety. U.S. Food and Drug Administration regulations and California law also establish contaminant limits in bottled water to provide protection for public health, though it’s tested less frequently than tap water.
Drinking water, including bottled water, may be expected to contain small amounts of contaminants; their presence doesn’t necessarily indicate that the water poses a health risk.
Naturally Occurring Drinking Water
Contaminants
Tap and bottled drinking water sources include rivers, lakes, streams, ponds, reservoirs, springs and wells. Travelling water dissolves naturally occurring minerals and, in some cases radioactive material, potentially picking up substances resulting from animal or human activity.
Naturally occurring source water contaminants may include:
• Microbials (viruses, bacteria) sewage treatment plants, septic systems, agricultural livestock operations or wildlife
• Inorganics (salts, metals): stormwater runoff, wastewater discharges, oil and gas production, mining, farming, naturally occurring
• Pesticides/herbicides: agriculture, stormwater runoff, landscaping • Organic chemicals: byproducts of synthetic and volatile organic chemical industrial processes and petroleum production or gas stations, stormwater runoff, agricultural and septic systems • Radioactive contaminants: naturally occurring or resulting from oil/gas production or mining activities
Arsenic and Perchlorate
Both Arsenic and Perchlorate were below their Public Health Goals, meaning there is no known or expected risk at their current levels in the City's drinking water.
Sources of arsenic occur from erosion of natural deposits, orchard runoff, and electronics and glass production wastes. Sources of perchlorate include rocket fuel, explosives and industrial uses and their resulting environmental contamination.
Lead
No Santa Clara water sources have exceeded the ACTION LEVEL for lead.
Lead levels in your home may be higher than others due to plumbing in your home’s original construction. Elevated lead levels can cause serious health problems, especially for pregnant women and young children.
Lead in drinking water comes from service line and home plumbing components. The City provides high quality drinking water, but cannot control materials used in your home’s plumbing. When water hasn’t been used for several hours, you can minimize potential lead exposure by:
1. Flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. (Use collected flushing water for cleaning, watering plants or running your garbage disposal.)
2. Using only cold water for drinking and cooking.
Concerned about lead in your water? Vi sit epa.gov/lead.
An initial lead service line inventory was completed in 2024 where more than 2,000 ser vice lines were inspected. No lead services were found during the inspections. A summary of the inventory can be found at SantaClaraCA.gov/WaterServiceLineInventory.
Nitrates in Groundwater Resources
Nitrate levels above 10 ppm in drinking water can interfere with the capacity of blood to carry oxygen in infants under six months old, pregnant women or those with specific enzyme deficiencies, resulting in serious illness. If you are pregnant or caring for an infant, consult your health care provider.
PFAS
Perfluoroalkyl and Polyfluoroalkyl substances, collectively known as PFAS, are a group of chemicals that have been widely used in industrial applications and consumer products such as carpets, clothing, furniture, fabrics, paper packaging for food, firefighting foams, and other materials including waterproof/stain resistant/nonstick cookware. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are two common types of PFAS. From 2019 to date, no PFAS compounds have been detected during the City's monitoring.
Hexavalent Chromium
Hexavalent Chromium, also known as Chromium-6, occurs naturally f rom the erosion of chromium deposits. It’ s used in various applications: paints, dyes, anticorrosion coatings and other industrial uses. As of October 1, 2024, the regulatory standard for Hexavalent Chromium is 10 ppb. Our 20 groundwater wells were tested for Hexavalent Chromium and were all found to be below 10 ppb.
Contaminant Regulations SFPUC Water: Tested for
Cryptosporidium & Giardia
Monthly (or more frequent) tests of SFPUC source and treated waters occasionally show very low levels of Cryptosporidium and Giardia in water serving the East Bay, South Bay and San Francisco Peninsula.
Cryptosporidiosis, an intestinal tract disease brought on by a parasitic microbe called Cryptosporidium, transmits through contaminated water, food or direct contact with human or animal waste. Giardia is caused by a different parasitic organism, but also causes symptoms similar to flu.
Symptoms usually last about two weeks for those with normal immune systems. Immuno-compromised people, infants, small children and the elderly are at greater risk of developing life-threatening illness.
Guidance from the California Department of Public Health and County health agencies recommend that people with serious immune problems consult their health care providers about preventing Cryptosporidium and Giardia infection. They may choose to bring drinking water to a rolling boil for at least one minute as an extra precaution.
Cryptosporidiosis and Giardiasis information and guidance:
• Santa Clara County Department of Environmental Health:
408-918-3400
Some Santa Clara Water is Fluoridated
Fluoridation adjusts naturally occurring fluoride in drinking water to the ideal level for protecting your teeth. Water purchased by the City from the SFPUC is fluoridated, while water from Valley Water is not.
If you’re in zip code 95054, you receive fluoridated water from the SFPUC that may be blended with unfluoridated well water. The area receiving a blend of water from both SFPUC and City wells are shown on the source water map included in this report. The majority of Santa Clara will continue to receive water without added fluoride. Contact your health care provider with any dental fluorosis concerns.
For more information, visit cdc.gov/fluoridation.
Leaks Sneak Up!
The EPA found that one in ten homes has a leak that wastes 90 gallons of water or more per day! Be diligent in checking for leaks in your home and landscape. Visit SantaClaraCA.gov/FixALeak for leak detection tips and to learn how the City can help.
Making Conservation A California Way
of Life
Last year, statewide rainfall topped 100% of average; now Moderate to Extreme drought conditions prevail in Southern California, while Abnormally Dry conditions threaten us. At our rainy season’s end, Santa Clara County rainfall year totaled just 68% of average. The State recognizes the ongoing drought reality:
• Making Conservation A California Way of Life regulations took effect statewide January 1.
• Urban Water Use Objective calls for a reduction to 47 gallons per capita per day from now until 2030.
• A drought emergency measure now permanently bans drinking water for irrigating non-functional turf at commercial, industrial, institutional (CII) and HOA properties with AB 1572, phasing in 2027.
Conservation remains critical to protect our drinking water supplies. Rain or shine, do your part to maximize water resources using free conservation devices and generous landscape rebates:
SantaClaraCA.gov/SaveOurWater.
Water & Sewer Utilities
1500 Warburton Ave.
Santa Clara, CA 95050
8 a.m.–5 p.m., Mon–Fri
408-615-2000, including emergencies
[email protected]
After-Hours Water Emergencies
408-615-5640
Water Billing Questions
408-615-2300
Water Quality Report Questions
Wendy Kwong
408-615-2000
[email protected]
Public Input
Provide input on decisions that affect drinking water
quality to Santa Clara City Council at a Council
meeting or in advance:
408-615-2250
[email protected]
A list of all City Council meetings, agenda items &
study sessions can be viewed on the City website at
SantaClara.Legistar.com/Calendar.aspx
Water Quality, Treatment &
Regulation Resources
American Water Works Association
AWWA.org
State Water Resources Control Board,
Division of Drinking Water
WaterBoards.CA.gov
United States Environmental Protection Agency
Water.epa.gov/Drink
San Francisco Public Utilities Commission,
Water Quality Bureau
SFWater.org
Valley Water
ValleyWater.org
Additional Water Quality Information
Attention
Mahalaga ang impormasyong ito. Mangyaring ipasalin ito.
This report contains important information about
your drinking water. Translate it, or speak with
someone who understands it.
Attencion: Este informe contiene informacion muy
importante sobre su agua beber. Traduzcalo o hable con
alguien que lo entienda bien.
PRSRT STD
US Postage
PAID
San Jose, CA
Permit #959
Published June 2025
2024
Water Quality
Consumer Confidence Report
CITY OF SANTA CLARA
1500 WARBURTON AVENUE
SANTA CLARA, CA 95050
The EPA and SWRCB prescribe regulations that limit the amounts of certain contaminants in water provided by public water systems to ensure its safety. U.S. Food and Drug Administration regulations and California law also establish contaminant limits in bottled water to provide protection for public health, though it’s tested less frequently than tap water.
Drinking water, including bottled water, may be expected to contain small amounts of contaminants; their presence doesn’t necessarily indicate that the water poses a health risk.
Naturally Occurring Drinking Water
Contaminants
Tap and bottled drinking water sources include rivers, lakes, streams, ponds, reservoirs, springs and wells. Travelling water dissolves naturally occurring minerals and, in some cases radioactive material, potentially picking up substances resulting from animal or human activity.
Naturally occurring source water contaminants may include:
• Microbials (viruses, bacteria) sewage treatment plants, septic systems, agricultural livestock operations or wildlife
• Inorganics (salts, metals): stormwater runoff, wastewater discharges, oil and gas production, mining, farming, naturally occurring
• Pesticides/herbicides: agriculture, stormwater runoff, landscaping • Organic chemicals: byproducts of synthetic and volatile organic chemical industrial processes and petroleum production or gas stations, stormwater runoff, agricultural and septic systems • Radioactive contaminants: naturally occurring or resulting from oil/gas production or mining activities
Arsenic and Perchlorate
Both Arsenic and Perchlorate were below their Public Health Goals, meaning there is no known or expected risk at their current levels in the City's drinking water.
Sources of arsenic occur from erosion of natural deposits, orchard runoff, and electronics and glass production wastes. Sources of perchlorate include rocket fuel, explosives and industrial uses and their resulting environmental contamination.
Lead
No Santa Clara water sources have exceeded the ACTION LEVEL for lead.
Lead levels in your home may be higher than others due to plumbing in your home’s original construction. Elevated lead levels can cause serious health problems, especially for pregnant women and young children.
Lead in drinking water comes from service line and home plumbing components. The City provides high quality drinking water, but cannot control materials used in your home’s plumbing. When water hasn’t been used for several hours, you can minimize potential lead exposure by:
1. Flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. (Use collected flushing water for cleaning, watering plants or running your garbage disposal.)
2. Using only cold water for drinking and cooking.
Concerned about lead in your water? Visit
epa.gov/lead.
An initial lead service line inventory was completed in 2024 where more than 2,000 service lines were inspected. No lead services were found during the inspections. A summary of the inventory can be found at SantaClaraCA.gov/WaterServiceLineInventory.
Nitrates in Groundwater Resources
Nitrate levels above 10 ppm in drinking water can interfere with the capacity of blood to carry oxygen in infants under six months old, pregnant women or those with specific enzyme deficiencies, resulting in serious illness. If you are pregnant or caring for an infant, consult your health care provider.
PFAS
Perfluoroalkyl and Polyfluoroalkyl substances, collectively known as PFAS, are a group of chemicals that have been widely used in industrial applications and consumer products such as carpets, clothing, furniture, fabrics, paper packaging for food, firefighting foams, and other materials including waterproof/stain resistant/nonstick cookware. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are two common types of PFAS. From 2019 to date, no PFAS compounds have been detected during the City's monitoring.
Hexavalent Chromium
Hexavalent Chromium, also known as Chromium-6, occurs naturally from the erosion of chromium deposits. It’ s used in various applications: paints, dyes, anticorrosion coatings and other industrial uses. As of October 1, 2024, the regulatory standard for Hexavalent Chromium is 10 ppb. Our 20 groundwater wells were tested for Hexavalent Chromium and were all found to be below 10 ppb.
Contaminant Regulations SFPUC Water: Tested for
Cryptosporidium & Giardia
Monthly (or more frequent) tests of SFPUC source and treated waters occasionally show very low levels of Cryptosporidium and Giardia in water serving the East Bay, South Bay and San Francisco Peninsula.
Cryptosporidiosis, an intestinal tract disease brought on by a parasitic microbe called Cryptosporidium, transmits through contaminated water, food or direct contact with human or animal waste. Giardia is caused by a different parasitic organism, but also causes symptoms similar to flu.
Symptoms usually last about two weeks for those with normal immune systems. Immuno-compromised people, infants, small children and the elderly are at greater risk of developing life-threatening illness.
Guidance from the California Department of Public Health and County health agencies recommend that people with serious immune problems consult their health care providers about preventing Cryptosporidium and Giardia infection. They may choose to bring drinking water to a rolling boil for at least one minute as an extra precaution.
Cryptosporidiosis and Giardiasis information and guidance:
• Santa Clara County Department of Environmental Health:
408-918-3400
Some Santa Clara Water is Fluoridated
Fluoridation adjusts naturally occurring fluoride in drinking water to the ideal level for protecting your teeth. Water purchased by the City from the SFPUC is fluoridated, while water from Valley Water is not.
If you’re in zip code 95054, you receive fluoridated water from the SFPUC that may be blended with unfluoridated well water. The area receiving a blend of water from both SFPUC and City wells are shown on the source water map included in this report. The majority of Santa Clara will continue to receive water without added fluoride. Contact your health care provider with any dental fluorosis concerns.
For more information, visit
cdc.gov/fluoridation.
Leaks Sneak Up!
The EPA found that one in ten homes has a leak that wastes 90 gallons of water or more per day! Be diligent in checking for leaks in your home and landscape. Visit SantaClaraCA.gov/FixALeak for leak detection tips and to learn how the City can help.
Making Conservation A California Way
of Life
Last year, statewide rainfall topped 100% of average; now Moderate to Extreme drought conditions prevail in Southern California, while Abnormally Dry conditions threaten us. At our rainy season’s end, Santa Clara County rainfall year totaled just 68% of average. The State recognizes the ongoing drought reality:
• Making Conservation A California Way of Life regulations took effect statewide January 1.
• Urban Water Use Objective calls for a reduction to 47 gallons per capita per day from now until 2030.
• A drought emergency measure now permanently bans drinking water for irrigating non-functional turf at commercial, industrial, institutional (CII) and HOA properties with AB 1572, phasing in 2027.
Conservation remains critical to protect our drinking water supplies. Rain or shine, do your part to maximize water resources using free conservation devices and generous landscape rebates:
SantaClaraCA.gov/SaveOurWater.
Water & Sewer Utilities
1500 Warburton Ave.
Santa Clara, CA 95050
8 a.m.–5 p.m., Mon–Fri
408-615-2000, including emergencies
[email protected]
After-Hours Water Emergencies
408-615-5640
Water Billing Questions
408-615-2300
Water Quality Report Questions
Wendy Kwong
408-615-2000
[email protected]
Public Input
Provide input on decisions that affect drinking water
quality to Santa Clara City Council at a Council
meeting or in advance:
408-615-2250
[email protected]
A list of all City Council meetings, agenda items &
study sessions can be viewed on the City website at
SantaClara.Legistar.com/Calendar.aspx
Water Quality, Treatment &
Regulation Resources
American Water Works Association
AWWA.org
State Water Resources Control Board,
Division of Drinking Water
WaterBoards.CA.gov
United States Environmental Protection Agency
Water.epa.gov/Drink
San Francisco Public Utilities Commission,
Water Quality Bureau
SFWater.org
Valley Water
ValleyWater.org
Additional Water Quality Information
Attention
Mahalaga ang impormasyong ito. Mangyaring ipasalin ito.
This report contains important information about
your drinking water. Translate it, or speak with
someone who understands it.
Attencion: Este informe contiene informacion muy
importante sobre su agua beber. Traduzcalo o hable con
alguien que lo entienda bien.
PRSRT STD
US Postage
PAID
San Jose, CA
Permit #959
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