Presented By
Reporting Y ear 2025
Este informe contiene información importante
sobre su agua potable. T raducirlo, o hablar con
alguien que lo entienda.
This report contains important information
about your drinking water. T ranslate it, or
speak with someone who understands it.
该报告包含有关您的饮用水的重要信息。
翻译一下， 或与理解它的人交谈
Báo cáo này chứa thông tin quan trọng về
nước uống của bạn. Dịch nó, hoặc nói chuyện
với người hiểu nó
이 보고서에는 식수에 관한 중요한 정보가
포함되어 있습니다. 번역해 보세요, 아니면
이해해주는 사람이랑 얘기해봐
برشلا هايم لوح ةماه تامولعم ىلع ريرقتلا اذه يوتحي
كلذ مهفي صخش عم ثدحتلا وأ ،اهمجرت .كب ةصاخلا
このレポー トには、 飲料水に関する重要な情報が含ま
れています。 それを翻訳して、 またはそれを理解してい
る 人 に 相 談 してくだ さ い
As Fullerton Water Department marks 120 years of delivering reliable, quality service, we celebrate the people who make it possible. This includes Pete Acosta (pictured right) whose remarkable 49-year career reflects the heart of our community. His dedication continues to inspire our mission.
Your 2026 Water Quality Report
S
ince 1990, California water utilities have been providing an annual Water Quality Report to their customers. This year’s report covers water quality testing for 2025 and has been prepared in compliance with regulations called for in the 1996 reauthorization of the Safe Drinking Water Act (SDWA). The reauthorization charged the U.S. Environmental Protection Agency (U.S. EPA) with updating and strengthening the tap water regulatory program.
U.S. EPA and the State Water Resources Control Board (SWRCB), Division of Drinking Water (DDW) are the agencies responsible for establishing drinking water quality standards. T o ensure that your tap water is safe to drink, U.S. EPA and DDW prescribe regulations that limit the amount of certain contaminants in water provided by public water systems. DDW regulations also establish limits for contaminants in bottled water that must provide the same protection for public health. The federal Food and Drug Administration also sets regulations for bottled water.
The City of Fullerton vigilantly safeguards its water supply, and as in years past, the water delivered to your home meets the standards required by the state and federal regulatory agencies. In accordance with the SDWA, the City monitors over 100 compounds in your water supply. This report includes only the compounds actually detected in the water. In some cases, the City goes beyond what is required by testing for unregulated contaminants that may have known health risks. For example, the Orange County Water District (OCWD), which manages our groundwater basin, monitors our groundwater for regulated and unregulated solvents, herbicides, and pesticides. Unregulated contaminant monitoring helps U.S. EPA determine where certain contaminants occur and whether it needs to establish regulations for those contaminants. The state allows us to monitor for some contaminants less than once per year because the concentrations of these contaminants do not change frequently. Some of our data, though representative, is more than a year old.
Sources of Supply
Y
our drinking water is a blend of primarily groundwater
from the Orange County groundwater basin and also
surface water imported by the Metropolitan Water District of Southern Califormia (MWDSC). MWDSC’s imported water
sources are the State Water Project from Northern California and the Colorado River Aqueduct. Your groundwater comes from a natural underground reservoir that stretches from the Prado Dam across the northwestern portion of Orange County, excluding the communities of Brea and La Habra, and stretching as far south as the El T oro Y.
The area map presented here will help you determine which source of water you are most likely to receive. Area 1 receives primarily groundwater and Area 3 imported water. Area 2 receives a mix of groundwater and imported water. Fullerton’s water system was built with maximum flexibility. We have eight active wells located in the southern portion of Fullerton and north Anaheim and seven active imported water connections. This means that under emergency, drought, or other unusual conditions, the source of water for any area may change. The area map reflects the source of water each area receives a majority of the time.
Quality Water is Our Priority
T
urn the tap and the water flows, as if by magic. Or so it seems. The reality is considerably different. Delivering high-quality drinking water to our customers is a scientific and engineering feat that requires considerable effort and talent to ensure the water is always there, always safe to drink. Because tap water is highly regulated by state and federal laws, water treatment and distribution operators must be licensed.
Our certified water professionals have an understanding of a wide range of subjects, including mathematics, biology, chemistry, physics, and engineering. Some of the tasks they complete on a regular basis include:
• Operating and maintaining equipment to purify and
clarify water;
• Monitoring and inspecting machinery, meters, gauges,
and operating conditions;
• Conducting tests and inspections on water and
evaluating the results;
• Documenting and reporting test results and system
operations to regulatory agencies; and
• Serving our community through customer support,
education, and outreach.
So the next time you turn on your faucet, think of the skilled professionals who stand behind every drop.
We Invite You to Learn More About
Your Water’s Quality
F
or information about this report, or your water quality in general, please contact the City of Fullerton Water Quality Supervisor at (714) 738-2835. The city council meets on the first and third T uesday of the month at 5:30 p.m. in Council Chambers at City Hall, 303 West Commonwealth Avenue.
Please feel free to participate in these meetings.
About Lead in Tap Water
L
ead can cause serious health problems, especially
for pregnant women and young children. Lead
in drinking water is primarily from materi -
als and components associated with service
lines and home plumbing. City of Fullerton
Water System Management is responsible for
providing high quality drinking water and
removing lead pipes, but cannot control the variety of materi - als used in plumbing components in your home. You share the responsibility for protecting yourself and your family from the lead in your home plumbing. You can take responsibility by identifying and removing lead materials within your home plumbing and taking steps to reduce your family’s risk. Before drinking tap water, flush your pipes for several minutes by running your tap, taking a shower, doing laundry or a load of dishes. You can also use a filter certified by an American National Standards Institute accredited certifier to reduce lead in drinking water. If you are concerned about lead in your water and wish to have your water tested, contact City of Fullerton Water Quality Supervisor at (714) 738-2835].
Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available at http:// www.epa.gov/safewater/lead.
Lead Service Line Inventory
T
o address lead in drinking water, public water systems
were required to develop and maintain an inventory
of service line materials by October 16, 2024. Developing an inventory and identifying the location of lead service lines (LSL) is the first step for beginning LSL replacement and protecting public health. Please visit epa.gov/ground- water-and-drinking-water/revised-lead-and-copper-rule to learn more. For more information about Fullerton’s service line inventory, please visit https://www.cityoffullerton.com/ government/departments/public-works/water-system/water- quality/service-line-inventory
Where Can You Learn More?
T
here’s a wealth of information on the internet about
drinking water quality and water issues in general. Some good sites to begin your research are:
• Metropolitan Water District of Southern California:
mwdh2o.com
• California Department of Water Resources: water.ca.gov • The Water Education Foundation: watereducation.org
T o learn more about water conservation and rebates:
• bewaterwise.com
• ocwatersmart.com
T o see the aqueducts in action, check out these two videos:
• Wings Over Water: youtu.be/8A1v1Rr2neU
• Wings Over Metropolitan’s Colorado Aqueduct: youtu.
be/KipMQh5t0f4
Important Health Information
S
ome people may
be more vulner -
able to contaminants
in drinking water than
the general population.
Immunocompromised
persons such as persons
with cancer undergo -
ing chemotherapy, per -
sons who have under -
gone 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. U.S. EPA/CDC guide- lines on appropriate means to lessen the risk of infection by Cryptosporidium and other microbial contaminants are avail - able from the Safe Drinking Water Hotline (1-800-426-4791).
Have you ever wondered where your water comes from? Here in the City of Fullerton, our water is drawn from local groundwater supplies, then blended with water imported from Northern California and the Colorado River. Water from Northern
California travels to us through a complex delivery system known as the California State Water Project. Designed and built in the 1960s, the State Water Project is one of the largest public water and power utilities in the world, providing drinking water for more than 25 million people statewide. Managed by the California Department of Water Resources, the project stretches over 700 miles from Lake Oroville in the north to Lake Perris in the south. Water stored in Lake Oroville, Folsom Lake, and other tributaries and fed by snowmelt from the Sierra Nevada Mountains flows into the Sacramento and San Joaquin Rivers, and from there into reservoirs in the Bay-Delta region.
From the Bay-Delta, giant pumps lift the water into the 444-mile-long California Aqueduct to flow southward to cities and farms in Central and Southern California. Composed mainly of concrete-lined canals, the aqueduct includes over 20 miles of tunnels, over 130 miles of pipelines, and 27 miles of siphons.
Along the way, the water is pumped 2,882 feet over
the T ehachapi Mountains. The Edmonston Pumping
Plant alone lifts millions of gallons a day up 1,926
feet, the highest single water lift in the world.
Is it any wonder the State Water Project is
the largest single consumer of power in
California?Managed by the MWDSC,
the Colorado River
Aqueduct begins near Parker
Dam on the Colorado River.
There, the Gene Pumping
Station lifts the water over 300
feet as it begins its 242-
mile journey to Lake
Mathews, just outside
the City of Corona.
Along the way, the
water passes through
two reservoirs, five
pumping stations, 62
miles of canals, and 176
miles of tunnels, buried
conduits, and siphons. All
told, the water is lifted four
times, for a total of more than 1,300 feet.
After its journey across the Mojave Desert, the water descends into the Coachella Valley and through the San Gorgonio Pass.
Near Cabazon, the aqueduct flows underground, passing beneath the San Jacinto Mountains and continuing until it reaches its terminus at Lake Mathews. From there, 156 miles of distribution lines, along with eight more tunnels and five drinking water treatment plants, deliver treated water throughout Southern California.
Where Does Our Water Comes From? And How Does it Get to Us?
How Does Our Water Get to Us?
I
mporting water from hundreds of miles away is only the
start to providing you clean, fresh water. Once the water is in Southern California, it is distributed to individual agen - cies and municipalities throughout the Southland by the MWDSC. The OCWD, which manages the groundwater
basin beneath the county, ensures the quality and supply of groundwater throughout its service area. The City of Fullerton sits atop the county aquifer and draws some of its water from this local source.
The City of Fullerton,
Water System Management
vigorously works to ensure
the safety of your drinking
water and, in conjunction
with the MWDSC and
OCWD, continuously
monitors the water to verify
adherence with drinking
water regulations.
Where Do We Use Water the Most?
O
utdoor watering of lawns and gardens makes up approximately 60 percent of home water use. By reducing your outdoor water use by either cutting back on irrigation or planting more drought-tolerant landscaping, you can dramatically reduce your overall water use. Save the most where you use the most—make your outdoor use efficient.
Cross Connections
E
ffective July 1, 2024, the State Water Resources Control Board (SWRCB) implemented updates to the Cross-Connection Control Policy Handbook (CCCPH). For information regarding the City of Fullerton’s Cross-Connection Control (CCC) Policy Handbook, please visit the official city website at www.cityoffullerton.com.
Eight locations in the distribution system are tested quarterly for total trihalomethanes and haloacetic acids. Thirty locations are tested monthly for color, odor and turbidity. Color was not detected in 2025.
MRDL = Maximum Residual Disinfectant Level; MRDLG = Maximum Residual Disinfectant Level Goal; ntu = nephelometric turbidity unit; ND = not detected; *Contaminant is regulated by a secondary standard to maintain aesthetic qualities.
LEAD AND COPPER ACTION LEVELS AT RESIDENTIAL TAPS
ACTION
LEVEL (AL)
PUBLIC
HEALTH GOAL
90TH PERCENTILE
VALUE
RANGE OF
DETECTIONS
SITES EXCEEDING AL
/ NUMBER OF SITES
AL
VIOLATION?
TYPICAL SOURCE OF
CONTAMINANT
Lead (ppb) 15 0.2 ND ND 0 / 54 No Corrosion of Household Plumbing Copper (ppm) 1.3 0.3 0.19 ND - 0.44 0 / 54 No Corrosion of Household Plumbing 2025 City of Fullerton Drinking Water Quality
F
or more information about the health effects of the listed contaminants in the following tables, call the U.S. EPA hotline at (800) 426-4791.
Every three years, at least 50 residences are tested for lead and copper at-the-tap. The most recent set of samples was collected in 2024. Copper was found in 35 homes; none exceeded the regulatory action level (AL). Lead was not detected in any home. The regulatory action level is the concentration which, if exceeded in more than ten percent of the homes tested, triggers treatment or other requirements that a water system must follow. The City of Fullerton complies with the lead and copper ALs.
Drinking Water Definitions
What are water quality standards?
Drinking water standards established by U.S. EPA and DDW set limits for substances that may affect consumer health or aesthetic qualities of drinking water.
The tables in this report show the following types of water quality standards:
• 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.
• 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.
• Secondary MCLs are set to protect the odor, taste, and appearance of drinking water.
• Primary drinking water standard: MCLs for contaminants that affect health, along with their monitoring and reporting requirements and water treatment requirements.
• Regulatory action level (AL): The concentration of a contaminant that, if exceeded, triggers treatment or other requirements that a water system must follow.
What is a water quality goal?
In addition to mandatory water quality standards, U.S. EPA and DDW have set voluntary water quality goals for some contaminants. Water quality goals are often set at such low levels that they are not achievable in practice and are not directly measurable. Nevertheless, these goals provide useful guideposts and direction for water management practices.
The tables in this report include three types of water quality goals:
• 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 U.S. EPA.
• 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 EPA.
How are contaminants measured?
Water is sampled and tested throughout the year. Contaminants are measured in:
• Parts per million (ppm) or milligrams per liter (mg/L) • Parts per billion (ppb) or micrograms per liter (µg/L) • Parts per trillion (ppt) or nanograms per liter (ng/L) 2025 CITY OF FULLERTON DISTRIBUTION SYSTEM WATER QUALITY
MCL (MRDL/
MRDLG)
AVERAGE
AMOUNT
RANGE OF
DETECTIONS
MCL
VIOLATION TYPICAL SOURCE OF CONTAMINANT
Disinfection Byproducts
Total Trihalomethanes (ppb) 80 32 9.3 - 44 No Byproducts of Chlorine Disinfection Haloacetic Acids (ppb) 60 10 1.1 - 12 No Byproducts of Chlorine Disinfection Chlorine Residual (ppm) (4 / 4) 1.3 ND - 3.2 No Disinfectant Added for Treatment Aesthetic Quality
Odor (threshold odor number) 3* ND ND - 2 No Erosion of Natural Deposits Turbidity (ntu) 5* 0.1 ND - 0.8 No Erosion of Natural Deposits Others
Fluoride (ppm) 2 0.6 0.39 - 0.68 No Erosion of Natural Deposits pH (pH Units) Not Regulated 8 6.9 - 9.3 n/a Acidity, Hydrogen Ions 2025 CITY OF FULLERTON GROUNDWATER QUALITY
CHEMICAL MCL
PHG
(MCLG)
AVERAGE
AMOUNT
RANGE OF
DETECTIONS
MCL
VIOLATION?
MOST RECENT
SAMPLING
DATE
TYPICAL SOURCE OF
CONTAMINATION
Radiologicals
Uranium (pCi/L) 20 0.43 3.1 1.3 - 6.4 No 2024 Erosion of Natural Deposits Organic Chemicals
Tetrachloroethylene, PCE (ppb) 5 0.06 ND ND - 0.7 No 2025 Industrial Waste Discharge Inorganic Chemicals
Arsenic (ppb) 10 0.004 ND ND - 2 No 2025 Erosion of Natural Deposits Fluoride (ppm) 2 1 0.52 0.47 - 0.57 No 2025 Erosion of Natural Deposits Hexavalent Chromium (ppb) 10 0.02 0.51 0.22 - 1.4 No 2025 Erosion of Natural Deposits Nitrate (ppm as N) 10 10 2.5 1.2 - 6.1 No 2025 Fertilizers, Septic Tanks Nitrate+Nitrite (ppm as N) 10 10 2.5 1.2 - 6.1 No 2025 Fertilizers, Septic Tanks Perchlorate (ppb) 6 1 ND ND - 2.5 No 2025 Industrial Discharge Selenium (ppb) 50 30 ND ND - 10 No 2025 Erosion of Natural Deposits Secondary Standards*
Chloride (ppm) 500* n/a 73 69 - 79 No 2025 Erosion of Natural Deposits Specific Conductance (µmho/cm) 1,600* n/a 775 683 - 1,070 No 2025 Erosion of Natural Deposits Sulfate (ppm) 500* n/a 131 101 - 200 No 2025 Erosion of Natural Deposits Total Dissolved Solids (ppm) 1,000* n/a 492 426 - 706 No 2025 Erosion of Natural Deposits Turbidity (ntu) 5* n/a 0.15 ND - 0.35 No 2025 Erosion of Natural Deposits Unregulated Chemicals
Alkalinity, total as CaCO3 (ppm) Not Regulated n/a 148 119 - 219 n/a 2025 Erosion of Natural Deposits Bicarbonate (ppm as HCO3) Not Regulated n/a 181 151 - 267 n/a 2025 Erosion of Natural Deposits Boron (ppm) NL=1 n/a 0.18 0.15 - 0.2 n/a 2025 Erosion of Natural Deposits Calcium (ppm) Not Regulated n/a 73 62 - 97 n/a 2025 Erosion of Natural Deposits Hardness, total (grains per gallon) Not Regulated n/a 14 11 - 22 n/a 2025 Erosion of Natural Deposits Hardness, total as CaCO3 (ppm) Not Regulated n/a 246 195 - 375 n/a 2025 Erosion of Natural Deposits Magnesium (ppm) Not Regulated n/a 16 11 - 33 n/a 2025 Erosion of Natural Deposits Perfluoro Butane Sulfonic Acid (ppt) NL = 500 n/a ND ND - 8.2 n/a 2025 Industrial Waste Discharge Perfluoro Butanoic Acid (ppt) Not Regulated n/a ND ND - 7.1 n/a 2025 Industrial Waste Discharge Perfluoro Heptanoic Acid (ppt) Not Regulated n/a ND ND - 5.3 n/a 2025 Industrial Waste Discharge Perfluoro Hexane Sulfonic Acid (ppt) NL = 3** n/a ND ND - 5.9 n/a 2025 Industrial Waste Discharge Perfluoro Hexanoic Acid (ppt) Not
Regulated**
n/a 4.4 ND - 13 n/a 2025 Industrial Waste Discharge
Perfluoro Octane Sulfonic Acid (ppt) NL = 6.5** 1 5 ND - 13 n/a 2025 Industrial Waste Discharge Perfluoro Octanoic Acid (ppt) NL = 5.1** 0.007 4 ND - 11 n/a 2025 Industrial Waste Discharge Perfluoro Pentanoic Acid (ppt) Not Regulated n/a 5.7 ND - 15 n/a 2025 Industrial Waste Discharge pH (pH unit) Not Regulated n/a 7.8 7.8 - 7.9 n/a 2025 Erosion of Natural Deposits Potassium (ppm) Not Regulated n/a 3.7 3 - 4 n/a 2025 Erosion of Natural Deposits Sodium (ppm) Not Regulated n/a 67 57 - 84 n/a 2025 Erosion of Natural Deposits ppb = parts-per-billion; ppm = parts-per-million; ppt = parts-per-trillion; pCi/L = picoCuries per liter; ntu = nephelometric turbidity units; ND = not detected; n/a = not applicable; MCL = Maximum Contaminant Level; (MCLG) = federal MCL Goal; PHG = California Public Health Goal; µmho/cm = micromhos per centimeter; NL = Notification Level;
* Contaminant is regulated by a secondary standard to maintain aesthetic qualities (taste, odor, color). **Effective October 29, 2025 the Notification Levels for Perfluoro Hexane Sulfonic Acid, Perfluoro Octanoic Acid, and Perfluoro Octane Sulfonic Acid were revised to 3.0 ppt, 4.0 ppt, and 4.0 ppt, respectively. A Notification Level for Perfluoro Hexanoic Acid of 1,000 ppt was also established.
UNREGULATED CHEMICALS REQUIRING MONITORING
CHEMICAL
NOTIFICATION
LEVEL PHG
AVERAGE
AMOUNT
RANGE OF
DETECTIONS MOST RECENT SAMPLING DATE
Lithium (ppb) n/a n/a 9.4 ND - 29 2025
Perfluoro Butane Sulfonic Acid (ppt)*** 500 n/a ND ND - 7.6 2025 Perfluoro Butanoic Acid (ppt)*** n/a n/a ND ND - 5.9 2025 Perfluoro Heptanoic Acid (ppt)*** n/a n/a ND ND - 4.8 2025 Perfluoro Hexane Sulfonic Acid (ppt)*** 3** n/a ND ND - 6.2 2025 Perfluoro Hexanoic Acid (ppt)*** n/a** n/a ND ND - 12 2025 Perfluoro Octane Sulfonic Acid (ppt)*** 6.5** 1 ND ND - 13 2025 Perfluoro Octanoic Acid (ppt)*** 5.1** 0.007 ND ND - 11 2025 Perfluoro Pentanoic Acid (ppt)*** n/a n/a 3 ND - 13 2025 *** Contaminant was also included as part of the unregulated chemicals requiring monitoring.
Drinking Water Contaminants
T
he sources of drinking water (both tap water and bottled water) include rivers, lakes, streams, ponds, reservoirs, springs, and wells. As water travels over the surface of the land or through the ground, it dissolves naturally occur - ring minerals and, in some cases, radioactive material and can pick up substances resulting from the presence of animals or from 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 result 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 the result of oil and gas production and mining activities.
T o ensure that tap water is safe to drink, the U.S. EPA and SWRCB prescribe regulations that limit the amount of certain contaminants in water provided by public water systems. 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 U.S. EPA’s Safe Drinking Water Hotline (1-800-426-4791).
2025 METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA TREATED SURFACE WATER
CONSTITUENT MCL
PHG
(MCLG)
DIEMER
AVERAGE
WEYMOUTH
AVERAGE
RANGE OF
DETECTIONS
MCL
VIOLATION? TYPICAL SOURCE IN DRINKING WATER
Radiologicals - Tested in 2023 and 2025
Gross Alpha Particle Activity
(pCi/L)
15 (0) ND ND ND - 5 No Erosion of Natural Deposits
Gross Beta Particle Activity
(pCi/L)
50 (0) ND ND ND - 6 No Decay of Natural and Man-made Deposits Uranium (pCi/L) 20 0.43 1 ND ND - 3 No Erosion of Natural Deposits Inorganic Chemicals - Tested in 2025
Aluminum (ppm) 1 0.6 0.058 0.096 ND - 0.1 No Treatment Process Residue, Natural Deposits
Barium (ppm) 1 2 0.13 0.129 0.129 - 0.13 No Refinery Discharge, Erosion of Natural Deposits
Bromate (ppb) 10 0.1 2.4 3 ND - 12 No Byproduct of Drinking Water Ozonation Fluoride (ppm) treatment-
related
2 1 0.7 0.7 0.5 - 0.8 No Water Additive for Dental Health Secondary Standards* - Tested in 2025
Aluminum (ppb) 200* 600 58 96 ND - 100 No Treatment Process Residue, Natural Deposits
Chloride (ppm) 500* n/a 92 92 84 - 99 No Runoff or Leaching from Natural Deposits Color (color units) 15* n/a 1 1 1 No Runoff or Leaching from Natural Deposits Specific Conductance (µmho/
cm)
1,600* n/a 873 868 754 - 987 No Substances that Form Ions in Water Sulfate (ppm) 500* n/a 182 176 139 - 218 No Runoff or Leaching from Natural Deposits Total Dissolved Solids (ppm) 1,000* n/a 545 536 456 - 625 No Runoff or Leaching from Natural Deposits Unregulated Chemicals - Tested in 2025
Alkalinity, total (ppm as
CaCO3)
Not Regulated n/a 108 110 93 - 124 n/a Runoff or Leaching from Natural Deposits Boron (ppm) Not Regulated n/a 0.13 0.13 0.13 n/a Runoff or Leaching from Natural Deposits Calcium (ppm) Not Regulated n/a 56 56 43 - 70 n/a Runoff or Leaching from Natural Deposits Hardness, total (ppm as
CaCO3)
Not Regulated n/a 236 234 189 - 280 n/a Runoff or Leaching from Natural Deposits Hardness, total (grains/gal) Not Regulated n/a 14 14 11 - 16 n/a Runoff or Leaching from Natural Deposits Magnesium (ppm) Not Regulated n/a 22 22 19 - 25 n/a Runoff or Leaching from Natural Deposits pH (units) Not Regulated n/a 8.3 8.2 8.2 - 8.3 n/a Hydrogen Ion Concentration Potassium (ppm) Not Regulated n/a 4.3 4.4 3.8 - 5 n/a Runoff or Leaching from Natural Deposits Sodium (ppm) Not Regulated n/a 88 89 78 - 100 n/a Runoff or Leaching from Natural Deposits Total Organic Carbon (ppm) Not Regulated n/a 2.4 2.5 1.6 - 2.8 n/a Various Natural and Man-made Sources MCL = Maximum Contaminant Level; PHG = California Public Health Goal; (MCLG) = federal MCL Goal; pCi/L = picoCuries per liter; ppm = parts per million; ppb = parts per billion; µmho/cm = micromhos per centimeter; ND = not detected; n/a = not applicable; * Constituent is regulated by a secondary standard to maintain aesthetic qualities (taste, odor, color).
METROPOLITAN WATER DISTRICT
FILTRATION PLANTS
TREATMENT
TECHNIQUE
DIEMER TURBIDITY
MEASUREMENTS
WEYMOUTH TURBIDITY
MEASUREMENTS
TT
VIOLATION?
TYPICAL SOURCE IN DRINKING
WATER
Turbidity - combined filter effluent
1) Highest single turbidity measurement
(NTU)
0.3 0.05 0.06 No Soil Runoff
2) Percentage of samples less than or
equal to 0.3 NTU
95% 100% 100% No Soil Runoff
Turbidity is a measure of the cloudiness of the water, an indication of particulate matter, some of which might include harmful microorganisms. Low turbidity in Metropolitan’s treated water is a good indicator of effective filtration. Filtration is called a “treatment technique” (TT). A treatment technique is a required process intended to reduce the level of chemicals in drinking water that are difficult and sometimes impossible to measure directly. NTU = nephelometric turbidity units
METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA UNREGULATED CONSTITUENTS REQUIRING MONITORING
CONSTITUENT NL PHG
AVERAGE
AMOUNT
RANGE OF
DETECTIONS MOST RECENT SAMPLING DATE
Lithium (ppb) n/a n/a 21 ND - 35 2023
NL = Notification Level
Source Water Assessment
Imported (MWDSC) Water Assessment
Every five years, MWDSC is required by the DDW to examine possible sources of drinking water contamination in its State Water Project and Colorado River source waters. The most recent surveys for MWDSC’s source waters are the Colorado River Watershed Sanitary Survey—2022 Update and the State Water Project Watershed Sanitary Survey—2021 Update. Water from the Colorado River is considered to be most vulnerable to contamination from recreation, urban/stormwater runoff, increasing urbanization in the watershed, and wastewater. Water supplies from Northern California’s State Water Project are most vulnerable to contamination from urban/stormwater runoff, wildlife, agriculture, recreation, and wastewater. U.S. EPA also requires MWDSC to complete a source water assessment (SWA) that uses information collected in the watershed sanitary surveys. MWDSC completed its SWA in December 2002.
The SWA is used to evaluate the vulnerability of water sources to contamination and helps determine whether more protective measures are needed. A copy of the most recent summary of the Watershed Sanitary Surveys or the SWA can be obtained by calling MWD at (800) CALL-MWD (800-225-5693).
Groundwater Assessment
An assessment of the drinking water sources for the City of Fullerton was completed in May 2002. The groundwater sources are considered most vulnerable to the following activities associated with contaminants detected in the water supply: chemical/petroleum processing/storage, dry cleaners, gas stations, known contaminant plumes, metal plating/finishing/fabricating, and plastics/synthetics producers. The groundwater sources are considered most vulnerable to the following: airport maintenance/fueling areas, confirmed leaking underground storage tanks, and high-density housing. A copy of the complete assessment is available at State Water Resources Control Board, Division of Drinking Water, 605 West Santa Ana Boulevard, Building 28, Room 325, Santa Ana, CA 92701. You may request a summary of the assessment by contacting the Water Quality Supervisor, City of Fullerton, 1580 West Commonwealth Avenue, Fullerton, CA 92833-2728 or (714) 738-2835.
Disinfectants and Disinfection
By-Products in Drinking Water
D
isinfection of drinking water
was one of the greatest public
health advancements of the 20th
century, significantly reducing the
spread of waterborne diseases caused
by bacteria and viruses. T oday chlorine
and chloramines are commonly used dis-
infectants to ensure safe drinking water.
How Disinfection Works
• Chlorine is added at the water source (groundwater wells or treatment plants) to kill harmful microorganisms.
• Residual chlorine remains in the distribution system to prevent bacterial growth in the pipes that carry water to homes and businesses.
• Chloramines, a combination of chlorine and ammonia,
are also used as a disinfectant and help reduce certain by-products.
Disinfection By-Products and Regulations
While effective, chlorine and chloramines can react with naturally occurring materials in water, forming disinfection by-products (DBPs), which may pose health risks. The most common DBPs are trihalomethanes (THMs) and haloacetic
acids (HAAs).
T o protect public health, the U.S. EPA regulates DBPs under the Safe Drinking Water Act.
• In 1979 the U.S. EPA set the maximum allowable total
THM level at 100 parts per billion (ppb).
• In 2002 the Stage 1 Disinfectants/Disinfection
Byproducts Rule lowered the limit to 80 ppb and added
HAAs to the list of regulated chemicals.
• In 2006 the Stage 2 Disinfectants/Disinfection
Byproducts Rule introduced further monitoring and
control measures.
• Full compliance began in 2012.
Your drinking water meets or exceeds all state and federal standards, with rigorous monitoring in place. We regularly test for DBPs and adjust treatment methods to maintain a safe balance between disinfection and by-product control.
Important Considerations
• Fish and aquatic pets: Chloramines can be toxic to fish and should be removed from water used in aquariums.
• Kidney dialysis patients: Chloramines must be filtered from water used in dialysis treatment—consult your
health-care provider.
For more information on water quality and regulations,
visit:
• U.S. EPA water regulations: epa.gov/sdwa
• SWRCB: waterboards.ca.gov
Your drinking water is treated, tested, and monitored to ensure it remains safe and reliable for you and your community.
Cryptosporidium
C
ryptosporidium is a microscopic organism that origi -
nates from animal and human waste and may be present
in surface water. When ingested, it can cause diarrhea, fever, and other gastrointestinal symptoms. In 2025, the MWDSC tested for Cryptosporidium and did not detect its presence in any water after it had been treated. If Cryptosporidium is ever detected in drinking water, it is effectively removed through a combination of sedimentation, filtration, and disinfection.
The U.S. EPA and the Centers for Disease Control and
Prevention (CDC) provide guidelines on how to reduce the risk of infection from Cryptosporidium and other microbial contaminants. For more information, contact the U.S. EPA’s Safe Drinking Water Hotline at (800) 426-4791 or visit epa. gov/safewater.
Nitrate Advisory
N
itrate in drinking water at levels above 10 milligrams per liter (mg/L) is a health risk for infants of less than six months of age. Such nitrate levels in drinking water can interfere with the capacity of the infant’s blood to carry oxygen, result - ing in a 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 indi - viduals, 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 advice from your health-care provider.
Drinking Water Fluoridation
F
luoride has been added to U.S. drinking water supplies
since 1945 to help prevent tooth decay. As of today, the majority of public water suppliers in the country, including the MWDSC, fluoridate their water. MWDSC began adding
fluoride in December 2007, complying with all provisions of California’s fluoridation system requirements. Fluoride levels in drinking water are regulated in California and limited to a maximum of 2 parts per million (ppm). Some local ground - water supplies naturally contain fluoride, but they are not supplemented with additional fluoride.
Additional Information
For more details on water fluoridation, please visit:
• U.S. Centers for Disease Control and Prevention
(CDC): cdc.gov/fluoridation or (800) 232-4636
• State Water Resources Control Board, Division of
Drinking Water: waterboards.ca.gov/drinking_water/
certlic/drinkingwater/Fluoridation.html
• American Dental Association: ada.org
• American Water Works Association: awwa.org
For specific inquiries about MWDSC’s fluoridation program, please contact MWDSC directly at (800) 225-5693.
PFAS Advisory
P
er- and polyfluoroalkyl substances (PFAS) are a group of human-made chemicals that have been used in various consumer prod - ucts since the 1940s due to their resistance to heat, water, oils, and stains. These chemicals are prevalent in the environment and have been detected in water supplies nationwide. Studies suggest that exposure to certain PFAS may pose health risks. The U.S. EPA and DDW have established health-based advisories for PFAS. If PFAS levels exceed these guidelines, water agencies must notify their governing bodies and take necessary actions, such as removing affected sources from service or implementing treatment solutions.
T o address PFAS contamination, water providers have conducted testing and taken proactive steps to ensure safe drinking water.
Regulatory actions: The U.S. EPA announced final National Primary Drinking Water Regulations for six PFAS in April 2024. Public water systems are required to monitor these substances, with full compliance expected by 2029.
For more details on PFAS regulations and water safety, visit:
• California State Water Resources Control Board, Division of Drinking Water: waterboards.ca.gov/pfas • Orange County Water District: www.ocwd.com/what-we-do/water-quality/pfas • U.S. EPA: epa.gov/pfas
Subsequent testing detected levels at or above response levels, and the City responded by temporarily discontinuing use of sources until appropriate treatment can be installed and/or notification can be provided. As of June 2021, we brought our first PFAS treat- ment plant online and a second treatment plant was brought online in October of 2024.
City of Fullerton, Water System Management
1580 W. Commonwealth Ave. • Fullerton, CA 92833-2728
(714) 738-6300 • cityoffullerton.com • [email protected]