01. PH – Apprvl and Adoption of City of Downey's Water System 2025 Public Health Goals Report

Item No. 1.

TO: HONORABLE MAYOR AND MEMBERS OF THE CITY COUNCIL
FROM: OFFICE OF THE CITY MANAGER
BY: MATTHEW BAUMGARDNER, DIRECTOR OF PUBLIC WORKS/CITY ENGINEER DATE: JUNE 9, 2026

ADOPTION OF A RESOLUTION APPROVING AND ADOPTING THE CITY OF DOWNEY SUBJECT:

WATER SYSTEM 2025 PUBLC HEALTH GOALS REPORT

EXECUTIVE SUMMARY
The City Council will conduct a public hearing and consider adopting a resolution approving and adopting the City of Downey Water System 2025 Public Health Goals Report. Such reports are required to be prepared by public water systems such as the City of Downey that serve greater than 10,000 service connections every three years.

The reports provide access to information on water quality measurements within the City of Downey.

RECOMMENDATION
That the City Council:

1. Conduct a public hearing concerning the City of Downey Water System 2025 Public Health Goals Report; and,

2. Adopt Resolution No. 26-8361, approving and adopting the City of Downey Water System 2025 Public Health Goals Report.

BACKGROUND
The California Health and Safety Code (HSC) requires public water systems serving more than 10,000 service connections to prepare a Public Health Goals (PHGs) Report every three years that provides information on the "detection" of any contaminants in the public water system that exceed the PHGs for those contaminants. The purpose of the PHGs Report is to provide water customers with access to information on levels of contaminants that fall below the "enforceable mandatory standards" such as Maximum Contaminant Levels (MCLs), but above the PHG level.

Drinking Water Standards, PHGs, and MCLGs
MCLs are established by the United States Environmental Protection Agency (USEPA) and the State Water Resources Control Board Division of Drinking Water (State Water Board). The HSC requires MCLs to be established at a level as close to its PHG as is technologically and economically feasible, placing primary emphasis on the protection of public health. Adopted MCLs are the criteria utilized to ensure that a public water system is in compliance with drinking water standards.

PHGs are "non -enforceable goals" established by the California Environmental Protection Agency (Cal -EPA) Office of Environmental Health Hazard Assessment (OEHHA) and are not required to be met by any public water system.

In situations where OEHHA has not adopted a PHG for a particular constituent, water suppliers are to use the Maximum Contaminant Level Goal (MCLG) adopted by the USEPA in place of the PHG when preparing the PHGs Report. PHGs and MCLGs are based solely on public health risk considerations. None of the practical risk - management factors that are considered by the USEPA or State Water Board in setting drinking water standards (MCLs) are considered in setting PHGs or MCLGs. These factors include analytical detection capability, availability of treatment technology, benefits, capital costs, and ongoing operational costs. PHGs and MCLGs are, or may be set at, very low levels where health risks are very low, if not zero. Determination of health risks at these low levels is frequently theoretically based on risk assessments with many assumptions and mathematical extrapolations.

ANALYSIS
Cit's 2025 PHG Report and Water Quality Data
The City of Downey Water System 2025 PHGs Report, included with Attachment A, was prepared in accordance with the above noted requirements and was made available for review on the City's website, at the City Clerk's office, and Public Works Department counter. A list of all regulated constituents and their MCLs and PHGs (or MCLGs) are included in the PHGs Report. Also included are the numerical public health risks associated with the MCL, PHG (or MCLG) of each constituent detected, 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 annualized cost of a treatment system.

The water quality data collected from the City's water system between calendar years 2022 and 2024 for the purpose of determining compliance with drinking water standards were considered in preparing the City's 2025 PHGs Report. Such water quality data were previously summarized in the City's 2022, 2023 and 2024 Annual Water Quality Reports (Consumer Confidence Report or CCR), which were made available to all water customers by direct mail and/or on the City's website before July 1st of each subsequent year.

Constituents Detected that Exceeded a PHG or MCLG
The following constituents were detected in one or more of the City's drinking water sources at levels above the PHG, or if no PHG above the MCLG:

Best
PHG or
Detection
Constituents
MCL
Available
(MCLG)
Average
Technologies
Arsenic (mg/L)

0.010

0.000004

0.00146
RO
Perfluorooctane
NA

0.000001

0.0000276

GAC/IX/RO
[PFOS] (mg/L)
Perfluorooctanoic
NA

0.00000007

0.0000117

GAC/IX/RO
Acid [PFOA] (mg/L)
Tetrachloroethylene

0.005

0.00006

0.00012
GAC
[PCE] (mg/L)
Hexavalent

0.010

0.00002

0.00022

IX/RCF/RO
Chromium (mg/L)

Gross -Alpha
15 (0)

1.87 RO
(pCi/L)
Uranium (pCi/L)
20 0.43

0.79 RO
Lead (mg/L) —

0.015

0.0002

0.0028
CC
Action Level
Total Coliform (%
o
5 /o
(0)

0.6 D
Positive Samples)
Notes:
mg/L - milligrams per liter (1 milligram = 0.001 grams) pCi/L - picoCuries per liter
CC — corrosion control
D - disinfection
GAC - granular activated carbon
IX — ion exchange
RCF — reduction -coagulation -filtration
RO - reverse osmosis
More detailed discussion and cost estimates for hypothetical treatment of the above constituents are provided below as well as in the attached PHGs Report.

Treatment Alternatives and Cost Estimates
Both the USEPA and State Water Board have adopted what are known as Best Available Technologies (BATs), which are the best-known methods of reducing contaminant levels to the MCL. Costs can be estimated for such technologies. However, since many PHGs and MCLGs are set much lower than the MCLs, it is not always possible or feasible to determine what treatments are needed to further reduce the constituents down to or near the PHG or MCLG many of which are set at zero.

Estimating treatment costs to reduce a constituent to a low PHG level (sometimes to laboratory non -detect levels or zero) is difficult, if not impossible, and highly speculative because it is not possible to verify by analytical means that the level has been lowered to zero. In some cases, installing a treatment facility to further reduce very low levels of one constituent may also cause adverse effects on other aspects of a system's water quality. Therefore, BATs for PHGs and MCLGs have limited value and do not warrant significant investment of time and money.

Where appropriate, the BATs that could be hypothetically used to reduce the levels of the constituents listed in the previous table and estimates of the annualized costs to design, construct, and operate the treatment facilities have been estimated for the purposes of the PHGs Report. The annualized costs assume that they will be equally shared by each of the approximately 23,500 service connections in the City's water system.

The costs associated with the BATs included in the PHGs Report do not include other costs, such as costs associated with demolition, property acquisition, groundwater well pump, and motor improvements necessary to overcome the increase in pressure loss associated with the treatment facilities, and increased electricity costs.

Further, the effectiveness of the treatment processes to provide significant reductions in constituent levels at these already low levels are uncertain. The health protection benefits of these further hypothetical reductions are not at all clear and may not be quantifiable. Therefore, no further action is recommended other than conducting a public hearing to consider comments as required by the HSC and adopting the resolution, which is included as Attachment A along with the City's 2025 PHGs Report.

It is important to note that the City's water system currently meets all State Water Board and USEPA drinking water standards set to protect public health. As provided in the PHGs Report, very costly treatment processes would be required to further reduce the levels of the small number of constituents detected, which are already significantly below the MCLs established to determine compliance with drinking water standards.

CITY COUNCIL PRIORITIES
Quality of Life, Safety and Infrastructure
Public Engagement

FISCAL IMPACT
This City's 2025 PGHs Report is being provided for informational purposes only for the City's water customers as required by the HSC. There is no fiscal impact associated with this action.

Attachments

RESOLUTION NO. 26-8361

A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF DOWNEY
APPROVING AND ADOPTING THE CITY OF DOWNEY WATER SYSTEM 2025

PUBLIC HEALTH GOALS REPORT
WHEREAS, Section 116470(b) of the California Health and Safety Code (HSC) specifies that a public water system serving more than 10,000 service connections must prepare a Public Health Goals (PHGs) Report every three years that provides information on the detection of any contaminants in the public water system that exceed the applicable PHGs for those contaminants; and
WHEREAS, the City of Downey is an urban supplier of water providing water to a population of approximately 111,000 through approximately 23,500 service connections; and WHEREAS, the City provides approximately 13,800 acre-feet of potable water to its customers on an annual basis; and
WHEREAS, the City of Downey Water System 2025 PHG Report (Report) has been prepared, such report having been last prepared in 2022; and WHEREAS, Section 116470(c) of the HSC requires that the Report be made available for public review and that a public hearing be held prior to adoption of the Report; and WHEREAS, the City has therefore prepared and made available for public review at the City Clerk's office, Public Works Department Counter, and on the City's website, draft copies of the Report, and provided proper notice of the Public Hearing to be held before the City Council of the City of Downey on June 9, 2026; and
WHEREAS, all remarks and suggestions brought to the attention of the City were considered prior to the approval and adoption of the Report.

NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF DOWNEY DOES HEREBY RESOLVE AS FOLLOWS:

SECTION 1. The City Council finds and determines that the foregoing Recitals are true and correct and incorporates the Recitals herein.

SECTION 2. The City Council hereby approves and adopts the City of Downey Water System 2025 Public Health Goals Report, a copy of which is attached as Exhibit A.

SECTION 3. This Resolution shall become effective upon its adoption.

SECTION 4. The City Clerk shall certify to the adoption of this Resolution.

APPROVED AND ADOPTED this 9th day of June, 2026.

CLAUDIA M. FROMETA, Mayor

RESOLUTION NO. 26-8361
PAGE 2
ATTEST:

MARIA ALICIA DUARTE, CMC
City Clerk
APPROVED AS TO FORM:
qft4'0k)V- FA. -A
JO M. FUNK
City Attorney
HEREBY CERTIFY that the foregoing Resolution was adopted by the City Council of the City of Downey at a Regular meeting held on the 911 day of June, 2026, by the following vote, to wit:

AYES Council Members:

NOES: Council Members:

ABSENT: Council Members:

ABSTAIN: Council Members:

MARIA ALICIA DUARTE, CMC
City Clerk

City of Downey Water System
2025 Public Health Goals Report
Utilities Division
Department of Public Works
9252 Stewart and Gray Road
Downey, CA 90241
NI Q T

Public Health Goals Report
The 2025 Public Health Goals (PHG) Report for the City of Downey Water System has been prepared in accordance with Section 116470 of the California Health and Safety Code, (HSC), which requires public water systems serving more than 10,000 service connections to provide information on the "detection" of any contaminant(s) exceeding a Public Health Goal (PHG) level.

The City's 2025 PHG Report is based on water quality analyses completed during calendar years 2022, 2023, and 2024, or in cases where water quality analyses during such years were not required, by using the most recent data available.

PHGs are "non -enforceable goals" established by the California Environmental Protection Agency (CalEPA) Office of Environmental Health Hazard Assessment (OEHHA) and are not required to be met by any public water system. OEHHA is the primary state entity responsible for the assessment of risks posed by chemical contaminants in the environment.

In situations where OEHHA has not adopted a PHG for a particular constituent, water suppliers are to use the Maximum Contaminant Level Goals (MCLGs) adopted by the United States Environmental Protection Agency (USEPA) in place of the PHG for that constituent when preparing the Report. MCLGs are the federal equivalent to PHGs.

The purpose of this report is to provide water customers with information on contaminants when their levels are detected above PHGs or MCLGs even though the levels are still in compliance with the enforceable mandatory drinking water standards referred to as Maximum Contaminant Levels (MCLs). In addition to providing information related to water quality, this PHG Report also includes estimated costs to hypothetically reduce or eliminate the trace amount of the contaminant(s) to at or below PHG (or MCLG if there is no PHG) levels without regard to how minimal the risk might be. Cost estimates are theoretical and include design, construction, and operational considerations for treatment facilities using the Best Available Technology (BAT).

Drinking Water Standards, MCLs, PHGs and MCLGs
The USEPA and the California State Water Resources Control Board (SWRCB) Division of Drinking Water (DDW) establish drinking water standards at very conservative levels to protect consumers from potential health risks. The MCL is the highest level of a contaminant allowed in drinking water. State MCLs cannot be less stringent than federal MCLs. MCLs are set at levels that take into consideration the cost of compliance based on available treatment technology for the contaminant. Adopted MCLs are the criteria utilized to ensure that a public

water system is in compliance with drinking water standards. California Health and Safety Code Section 116365(a) requires MCLs to be established at a level as close to its PHG as is technologically and economically feasible, placing primary emphasis on the protection of public health. Therefore, drinking water which meets SWRCB DDW standards is associated with little to no risk.

PHGs set by OEHHA are based solely on public health risk considerations. PHGs and MCLGs are set at very low levels where health risks are very low and in some cases zero. Health risks determined at these low levels are frequently based on theoretical risk assessment with many assumptions and mathematical extrapolations. Practical risk -management factors, such as analytical detection capability, availability of treatment technology, benefits, capital costs, and ongoing operational costs which are considered by the USEPA and SWRCB DDW when setting enforceable drinking water standards such as MCLs, are not considered when setting PHGs or MCLGs.

PHGs and MCLGs are not regulatory in nature and represent only non -enforceable theoretical goals. A list of all regulated contaminants along with their MCLs and PHGs (or MCLGs) is included as Attachment No. 1 to this Report.

Water Quality Data Considered
All the water quality data collected from the City's water system between calendar years 2022 and 2024 for the purposes of determining compliance with drinking water standards were considered in preparing this Report. Such water quality data were summarized in the City's 2022, 2023, and 2024 Annual Water Quality Reports (Consumer Confidence Report or CCR) (Attachment Nos. 2-4), which were each made available to all water customers by direct mail and/or posting on the City's website.

The 2025 PHG Report provides all information required in accordance with HSC Section 116470 for any constituents that were detected in the City's water supply at a level above an applicable PHG or MCLG.

Such information included in this Report includes: the numerical public health risk associated with the MCL and PHG (or MCLG) for the constituent in question, the category or type of risk to health that could be associated with each constituent level, and an estimate of the annualized cost of a treatment system for the constituent if feasible.

Best Available Treatment Technology and Cost Estimates
Both the USEPA and the DDW adopt what are known as BATS or Best Available Technologies which are the best known methods of reducing contaminant levels to the MCL. However, since many PHGs and MCLGs are set much lower than the MCLs, it is not always possible or feasible to determine what treatment is needed to further reduce a constituent down to or near the PHG or MCLG for a particular constituent, many of which are set at zero. 3 Estimating the costs to reduce a constituent to a low PHG level (sometimes to non -detect levels or zero) is difficult, if not impossible, and highly speculative because it is not always possible to verify constituents at such low levels. Some constituents considered to be carcinogenic have MCLGs designated as zero, which cannot be measured by practically available analytical methods. In some cases, installing a treatment facility to further reduce levels of one constituent that is already at a very low level may also cause adverse effects on other aspects of a system's water quality, requiring additional treatment and additional costs.

Where the best available technology that could be used to reduce the constituent level in question exists, the annualized costs to design, install, and operate such treatment equipment have been estimated. The annualized costs assume that they will be equally shared by each of the approximately 23,500 service connections in the City's water system.

The following provides information on constituents that were detected in one or more of the City's drinking water sources at a level above the PHG, or the MCLG. The table below is a summary of those constituents, BATS, and numerical health risk.

Numerical
Numerical
Aggregate
Detection
Cancer
Constituents
Units
MCL
PHG or
Detection
Risk 1at
Cancer
BATS
Cost Per
(MCLG)*
Range
Risk 1at
Year
Average
PHG or
MCL
(Million)
MCLG
Arsenic
mg/L

0.010

0.000004

0.00146
0 - 0.0025
1x10-6

2.5x10-3
RO
$9.13
Perfluorooctane
mg/L
NA

0.000001

0.0000276
.0000078
1x10-6
NA

GAC/IX/RO
Sulfonate (PFOS)
.0000458
$11.43
Perfluorooctanoic
mg/L
NA

0.00000007

0.0000117
000004
1x10-6
NA

GAC/IX/RO
Acid (PFOA)
.000015
Tetrachloroethylene
mg/L

0.005

0.00006

0.00012
0 - 0.00255
1x10-6
8x10-6
GAC
$7.82
(PCE)
Hexavalent
mg/L

0.010

0.00002

0.00022
0 .001
1x10-6
5x104

IX/RCF/RO
$7.43
Chromium
Gross -Alpha
pCi/L
15 (0)

1.87 0 - 6.01
0 1x10-3
RO
$10.75
Uranium
pCi/L
20 0.43

0.79 0-3.6
1x10-6
5x10-5
RO
$6.45
Lead z Action Level
mg/L

0.015

0.0002

0.0028
NA
<1x10-6
2x10-6
CC
Total Coliform
%
5%
(0)

0.6 0-4.4
NA
NA
D
Positive
0 NOTES:
*MCLGs are shown in parenthesis. MCLGs are
provided only when no applicable PHG exists.
l Cancer Risk= Upper estimate of excess cancer risk
per number of people exposed, resulting from
lifetime exposure. Actual cancer risk may be lower or
zero. Based on the OEHHA PHG technical support
document unless otherwise specified.
z AL= Action Levels for copper and lead refer to a
concentration measured at the tap. Much of the
copper and lead in drinking water is derived from
household plumbing (The Lead and Copper Rule, Title
22, California Code of Regulations [CCR] Section
64672.3).

Arsenic

TREATMENT/CONTROL TECHNOLOGIES
GAC=Granular Activated Carbon
RO=Reverse Osmosis
CC=Corrosion Control
D=Disinfection
IX= Ion Exchange
RCF= Reduction- Coagulation- Filtration
TERMS/ABBREVIATIONS:

NA=Not Applicable
AL=Action Level
BAT=Best Available Technology
mg/L=milligrams per liter or parts per million
pCi/L= picoCuries per liter
MCL= Maximum Contaminant Level
MCLG= Maximum Contaminant Level Goal
PHG=Public Health Goal
Arsenic has been detected from all water wells in the City water system. The MCL for Arsenic is 0.010 milligrams per liter (mg/L) and the PHG is 0.000004 mg/L (4 parts per trillion or ppt). As provided in the previous table the Arsenic levels detected in the City's system were below the MCL but above the PHG level.

Arsenic is a naturally occurring element in the earth's crust and is widely distributed in the environment. All humans are exposed to microgram quantities of arsenic largely from food and to a lesser degree from drinking water and air. The PHG of 0.000004 mg/L for arsenic in drinking water is derived based on the mortality of arsenic -induced lung and urinary bladder cancers observed in the epidemiological studies. Similar unit risks were derived from a mouse bioassay using prenatal exposure to arsenic. The risk estimates were based on a low -dose linear extrapolation approach although the mode of carcinogenic action is not fully understood.

The applicable BAT identified to treat arsenic is Reverse Osmosis (RO) treatment. The City has determined that the cost to install and operate a RO removal system to treat the subject wells in the water system to meet PHG levels would be up to $9.13 Million annually, which includes construction and annual operational cost. This translates into an annual cost of $389 per water service connection.

Tetrachlorethylene (PCE)
There are a total of three wells that have PCE levels below the MCL of 0.005 milligrams per liter (mg/L) but above the PHG of 0.00006 mg/L. The PHG was derived based on research showing incidences of cancer and leukemia in mice and rats exposed to PCE over a lifetime.

Constituents that cause cancer in laboratory animals also may increase the risk of cancer

in humans who are exposed over long periods of time. However, per the SWRCB, MCLs are established at levels as close to their PHG as is technologically and economically feasible, placing primary emphasis on the protection of public health therefore water which meets the drinking water standard (the MCL) is associated with little to no risk with respect to PCE.

A feasible BAT for removal of PCE is Granular Activated Carbon (GAC). The estimated cost to install and operate such treatment systems on three wells would be up to $7.82 Million per year including annualized capital and operation and maintenance costs. This would result in an assumed increased cost for each water service connection of $333 per year.

Gross Alpha, Combined Radium, and Uranium.

Gross Alpha has been detected from 11 wells in the system. The MCL for gross alpha is 15 pico Curies per Liter (pCi/L) and the MCLG is 0 pCi/L. The levels detected in the City's system were below the MCL, but were over MCLG levels set by USEPA. Uranium has been detected from 12 wells in the system. The MCL for uranium is 20 pCi/L and the PHG is 0.43 pCi/L. The levels detected in the City's system were below the MCL at all times, but were over the PHG level.

These radiological constituents are naturally occurring contaminants in water supplies.

These constituents have been shown to cause cancer in laboratory animals such as rats and mice when the animals are exposed to high levels over their lifetimes. These constituents that cause cancer in laboratory animals also may increase the risk of cancer in humans who are exposed over long periods of time.

The BAT for the removal of gross alpha radioactivity in drinking water for large water systems is reverse osmosis, which can also remove uranium. The City has estimated that the cost to install and operate RO systems at the City's well sites to meet the PHG levels would be up to approximately $17.2 Million annually, which includes construction and annual operational costs. This translates into an annual cost of $732 per water service connection.

Lead
The SWRCB through the DDW enforces the Lead and Copper Rule, which follows the US EPA's Lead and Copper Rule, and is used to protect the public's drinking water from metals that can adversely affect public health. Lead and copper are not present in our water sources, but they can leach into drinking water through the resident's plumbing systems and faucets. The Lead and Copper Rule requires water systems to monitor lead and copper levels at the consumers' taps.

There is no MCL for lead or copper. Instead of MCLs, every three years a set of special samples are collected and the results evaluated to determine whether the City's water system has achieved "optimized corrosion control. The 90th percentile value of all samples collected from household taps in the distribution system cannot exceed an Action Level of

0.015 mg/L for lead and 1.3 mg/L for copper. If Action Levels for lead or copper are exceeded, installation or modifications to corrosion control treatment is required. The PHG for lead is 0.0002 mg/L and the PHG for copper is 0.3 mg/L. The categories of health risk associated with lead include damage to nervous system (neurobehavioral effects in children) and kidneys, high blood pressure, and cancer.

Based on the last round of sampling for lead and copper in 2023, the 901h percentile value for lead was 0.0028 mg/L and 0.23 mg/L for copper. The value for copper was lower than the PHG, but the level of lead was higher than its corresponding PHG. However, both lead and copper results were below the Action Levels, which means the City's system continued to meet water quality standards and is in full compliance with the Lead and Copper Rule.

Therefore, the City system is considered by the DDW to have "optimized corrosion control." Optimizing corrosion control is considered to be the BAT to deal with corrosion issues and any lead or copper findings. The City continues to monitor its water quality parameters that relate to corrosivity, such as the pH, hardness, alkalinity, and total dissolved solids, and will take action if necessary to maintain the system in an "optimized corrosion control" condition.

Since the City is meeting the "optimized corrosion control" requirements, it is not prudent to initiate additional corrosion control treatment as it involves the addition of other chemicals and there could be additional water quality issues created as a result of doing so.

Therefore, no estimate of cost has been included.

Hexavalent Chromium
Hexavalent chromium, commonly referred to as chromium-6, is a toxic form of chromium.

OEHHA's scientific analysis has classified Chromium-6 as a known human carcinogen via ingestion. Exposure to chromium-6 in drinking water has been linked primarily to increased risks of gastrointestinal cancers. Recognizing these risks, OEHHA adopted the nation's first PHG for chromium-6 in July 2011. The final technical support document, published on July 29, 2011, set the PHG at just 0.00002 mg/L (0.02 parts per billion), corresponding to an estimated excess lifetime cancer risk of one in one million. This stringent goal underscores OEHHA's commitment to minimizing public exposure to chromium-6. On April 17, 2024, the State Water Board adopted a new MCL of 10 ppb for hexavalent chromium, which became effective October 1, 2024. In the more recent rule making in 2024 the State Water Board's final statement of reasons specifies a detection limit of .0001 mg/L.
6 With the new detection limits, 17 of Downey's wells detected Chromium-6 below the 10 µg/L (.01 mg/L) MCL but above the PHG of 0.02 µg/L (0.00002 mg/L). Results range from Non -detect to 1 µg/L (0 - .001 mg/L) with an average of .22 µg/L (.00022 mg/L).

According to the SWRCB DDW, three primary BATs identified for Hexavalent Chromium removal to meet the .01 mg/L MCL are: Ion Exchange (IX), Reduction -Coagulation - Filtration (RCF), and RO. While the PHG of 0.02 µg/L (0.00002 mg/L) is the scientifically ideal target based on cancer risk, currently available technology and cost models do not support achieving that level in a practical, economically sustainable way for public water systems. Based on the technology and information available today, treatment costs to meet PHG levels are estimated to be up to $7.43 Million annually, which includes construction and annual operational cost. This translates into an annual cost of $316 per water service connection.

Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonic Acid (PFOS) For more than a half -century, PFOA and PFOS were widely used in industrial applications and consumer products, notably, PFOA in nonstick cookware and PFOS in stain and water - repellant fabrics and in fire -fighting foams. The manufacture of these chemicals was phased out in the US following concerns about their extreme persistence in the environment and their detection in virtually all human blood serum samples. Although levels in the environment have declined from their peak around the year 2000, PFOA and PFOS continue to be present in the environment and are found in California drinking water.

On April 5, 2024, OEHHA formally adopted PHGs for PFOA at 0.007 ppt (parts per trillion) and PFOS at 1 ppt in drinking water. These PHGs are set at a risk level corresponding to one additional cancer case per one million people exposed over a lifetime. While the PHGs themselves are not enforceable, they guide the SWRCB in establishing MCLs for drinking water. Additionally, DDW has established notification levels and response levels of 4 ppt and 10 ppt for PFOA and 4 ppt and 40 ppt for PFOS respectively.

Because exposure to these chemicals in the environment is so prevalent and elimination times are so long, it is critical to understand the toxicity associated with these compounds, and their impacts on human health. Scientific studies show adverse health effects of PFOA and PFOS in people exposed at environmental levels, and similar effects in laboratory animals. There is evidence from epidemiologic studies that exposure to PFOA increases the risk of kidney cancer. Human exposure to PFOA is also associated with liver and immune system toxicity and increased total cholesterol, and there is suggestive evidence of an association with risk of preeclampsia and pregnancy -related hypertension. PFOS is also associated with immune system toxicity and increased total cholesterol in humans, with suggestive evidence of an association with risk of preeclampsia and pregnancy -related

hypertension. The effects seen in humans are supported by studies in laboratory animals, which show that PFOA and PFOS can cause liver toxicity, immunotoxicity, thyroid toxicity, developmental -reproductive toxicity, and cancer. A PHG is the concentration of a contaminant in drinking water that is estimated to pose no significant health risk to individuals consuming the water on a daily basis over a lifetime. The PHG for PFOA is based on kidney cancer in humans, while the PHG for PFOS is based on liver and pancreatic tumor data from rat studies.

BATs identified for removal of PFOA and PFOS are GAC, IX, and RO/Membrane Processes based on regulatory guidance, case studies, and technology reviews. The City has estimated that the cost to install and operate IX systems to meet the PHG levels would be up to approximately $11.43 Million annually, which includes construction and annual operational costs. This translates into an annual cost of $487 per water service connection.

Coliform Bacteria
The MCL for coliform bacteria is 5% positive samples of the total system samples collected per month and the MCLG is zero. The reason for the coliform drinking water standard is to minimize the possibility of water containing pathogens which are organisms that cause waterborne disease. Coliform is only a surrogate indicator of the potential presence of pathogens, therefore, it is not possible to quantify a specific numerical health risk.

Coliform bacteria are an indicator organism that are ubiquitous in nature and are not generally considered harmful. They are used because of the ease in monitoring and analysis. If a positive sample is found, it indicates a potential problem that needs to be investigated. It is not at all unusual for a system to have an occasional positive sample. It is difficult, if not impossible to assure that a system will never detect a positive sample. Per the California Total Coliform Rule and the Federal Revised Total Coliform Rule, the City collects 25 total coliform samples weekly throughout the distribution system. During the 3-year period from 2022 to 2024, monthly positive total coliform percentage results had an average detection of 0.60% and ranged from 0% to 4.4%. All positive samples were followed by corresponding actions including collecting confirmation samples, investigating, and correcting the cause of positive samples. In response to positive samples, precautionary flushing and/or chlorination was performed as considered appropriate until samples determined that the water was total coliform free.

Although USEPA set the MCLG for total coliform at zero percent positive, there is no commercially available technology that will guarantee zero percent positive every single month, therefore, the cost of achieving the PHG cannot be estimated.

The City has implemented and will continue to utilize proactive measures and BATs to prevent any microbiological contamination. These include protection of wells by 9 appropriate construction and maintenance, proper preventative maintenance of the distribution system by flushing, maintaining an effective cross -connection control program, maintaining positive pressures in the water distribution system, and conducting an effective sampling program that includes water quality monitoring of the distribution system and City wells.

All contaminants
Contaminants listed in the attached table may be removed to non -detectable levels, with the exception of lead and total coliform, which can be introduced anywhere in the distribution system regardless of treatment. The cost estimate to treat the water produced by the City to remove contaminants detected above the PHGs or MCLGs was calculated using a combination of RO, GAC, IX and RFC. Achieving the PHG or MCLG water quality goals are estimated to cost up to $53 Million per year, or $2,256 per service connection per year. It is important to note that this cost estimate is for treatment only and does not include costs associated with demolition, property acquisition, groundwater well pump and motor improvements necessary to overcome the increase in pressure loss associated with the treatment facilities, and increased electricity costs. Therefore, the estimated total cost to treat arsenic, gross alpha, uranium, PFAS, PFOA, Hexavalent Chromium, and PCE to PHG levels would be even greater than the estimate noted above.

The drinking water quality of the City of Downey's water system meets all State and Federal drinking water standards set to protect public health. Additional costly treatment processes would be required to further reduce the levels of the constituents identified in this Report, which are already significantly below the MCLs established to provide drinking water with primary emphasis placed on public health. The effectiveness of the treatment processes to provide significant reductions in constituent levels at these already low values is uncertain. The health protection benefits of these further hypothetical reductions are not all clear and may not be quantifiable. Therefore, no action is proposed.

1. Table of Regulated Contaminants with MCLs, PHGs or MCLGs

2. Water Quality Report for 2022.

3. Water Quality Report for 2023.

4. Water Quality Report for 2024.

MCLs, DLRs, and PHGs for Regulated Drinking Water Contaminants (Units are in milligrams per liter (mg/L), unless otherwise noted.) Last Update: June 1, 2025
This table includes:

California's maximum contaminant levels (MCLs)
Detection limits for purposes of reporting (DLRs)
Public health goals (PHGs) from the Office of Environmental Health Hazard Assessment LQEHHA Also, the PHG for NDMA (which is not yet regulated) is included at the bottom of this table.

Regulated Contaminant
MCL
DLR
PHG
Date of PHG
Chemicals with MCLs in 22 CCR §64431-inorganic Chemicals Aluminum
1 0.05

0.6 2001
Antimony

0.006

0.001
2016
Arsenic

0.010

0.002

0.000004
2004
Asbestos (MFL = million fibers per liter; for fibers >10 microns Ion
7 MFL

0.2 MFL
7 MFL
2003
Barium
1 0.1
2 2003
Beryllium

0.004

0.001

0.001
2003
Cadmium

0.005

0.001

0.00004
2006
Chromium, Total - OEHHA withdrew the 0.0025-mg/L
PHG

0.05 0.01
withdrawn
Nov. 2001
1999
Chromium, Hexavalent - 0.01-mg/L MCL & 0.001-
mg/L DLR repealed September 2017

0.01 0.0001

0.00002
2011
Cyanide

0.15 0.1

0.15 1997
Fluoride
2 0.1
1 1997
Mercury (inorganic)

0.002

0.001

0.0012
1999
rev2005 *
Nickel

0.1 0.01

0.012
2001
Nitrate (as nitrogen, N)
10 as N

0.4 45 as
NO3 (=10
Aq NI
2018
Nitrite (as N)
1 as N

0.4 1 as N
2018
Nitrate + Nitrite (as N)
10 as N
--
10 as N
2018
Perchlorate

0.006

0.002

0.001
2015
Selenium

0.05 0.005

0.03 2010
Thallium

0.002

0.001

0.0001
1999
(rev2004)
Copper and Lead, 22 CCR §64672.3
Values referred to as MCLs for lead and; copper are not actually MCLs; instead, they are called 'Action Levels" under the lead and copper rule
Copper

1.3 1 0.05
1 0.3
1 2008
Lead

0.015
1 0.005
1 0.0002
1 2009

Radionuclides with MCLs in 22 CCR §64441 and §64443-Radiological [units are picocuries per liter (pCi/L), unless otherwise stated; n/a = not applicable] Gross alpha particle activity - OEHHA concluded in
2003 that a PHG was not practical
15 3
none
n/a
Gross beta particle activity - OEHHA concluded in
2003 that a PHG was not practical
4 mrem/yr
4 none
n/a
Radium-226
--
1 0.05
2006
Radium-228
--
1 0.019
2006
Radium-226 + Radium-228
5 --
--
--
Strontium-90
8 2

0.35 2006
Tritium
20,000
1,000
1 400
2006
uranium
20 1

0.43 2001
Chemicals with MCLs in 22 CCR §64444-Organic Chemicals
(a) Volatile Organic Chemicals (VOCs)
Benzene

0.001

0.0005

0.00015
2001
Carbon tetrachloride

0.0005

0.0001
2000
1,2-Dichlorobenzene

0.6 0.0005

0.6 1997
rev2009
1,4-Dichlorobenzene (p-DCB)

0.005

0.0005

0.006
1997
1,1-Dichloroethane (1,1-DCA)

0.005

0.0005

0.003
2003
1,2-Dichloroethane (1,2-DCA)

0.0005

0.0004
1999
(rev2005)
1,1-Dichloroethylene (1,1-DCE)

0.006

0.0005

0.01 1999
cis-1,2-Dichloroethylene

0.006

0.0005

0.013
2018
trans- 1,2-Dichloroethylene

0.01 0.0005

0.05 2018
Dichloromethane (Methylene chloride)

0.005

0.0005

0.004
2000
1,2-Dichloropropane

0.005

0.0005

0.0005
1999
1,3-Dichloropropene

0.0005

0.0002
1999
(rev2006)
Ethylbenzene

0.3 0.0005

0.3 1997
Methyl tertiary butyl ether (MTBE)

0.013

0.003

0.013
1999
Monochlorobenzene

0.07 0.0005

0.07 2014
Styrene

0.1 0.0005

0.0005
2010
1,1,2,2-Tetrachloroethane

0.001

0.0005

0.0001
2003
Tetrachloroethylene (PCE)

0.005

0.0005

0.00006
2001
Toluene

0.15 0.0005

0.15 1999
1,2,4-Trichlorobenzene

0.005

0.0005

0.005
1999
1,1,1-Trichloroethane (1,1,1-TCA)

0.2 0.0005
1 2006
1,1,2-Trichloroethane (1,1,2-TCA)

0.005

0.0005

0.0003
2006
Trichloroethylene (TCE)

0.005

0.0005

0.0017
2009
Trichlorofluoromethane (Freon 11)

0.15 0.005

1.3 2014
1,1,2-Trichloro-1,2,2-Trifuoroethane (Freon 113)

1.2 0.01
4 1997
rev2011
Vinyl chloride

0.0005

0.00005
2000
Xylenes

1.75 0.0005

1.8 1997

(b) Non -Volatile Synthetic Organic Chemicals (SOCs)
Alachlor

0.002

0.001

0.004
1997
Atrazine

0.001

0.0005

0.00015
1999
Bentazon

0.018

0.002

0.2 1999
(rev2009)
Benzo(a)pyrene

0.0002

0.0001

0.000007
2010
Carbofuran

0.018

0.005

0.0007
2016
Chlordane

0.0001

0.00003
1997
(rev2006)
Chlorobenzene

0.07 0.00085

0.07 2014
Dalapon

0.2 0.01

0.79 1997
(rev2009)
1,2-Dibromo-3-chloropropane (DBCP)

0.0002

0.00001

0.000003
2020
2,4-Dichlorophenoxyacetic acid (2,4-D)

0.07 0.01

0.02 2009
Di(2-ethylhexyl)adipate

0.4 0.005

0.2 2003
Di(2-ethylhexyl)phthalate (DEHP)

0.004

0.003

0.012
1997
Dinoseb

0.007

0.002

0.014
1997
rev2010
Diquat

0.02 0.004

0.006
2016
Endothal

0.1 0.045

0.094
2014
Endrin

0.002

0.0001

0.0003
2016
Ethylene dibromide (EDB) (1,2-Dibromoethane)

0.00005

0.00002

0.00001
2003
Glyphosate

0.7 0.025

0.9 2007
Heptachlor

0.00001

0.000008
1999
Heptachlor epoxide

0.00001

0.000006
1999
Hexachlorobenzene

0.001

0.0005

0.00003
2003
Hexachlorocyclopentadiene

0.05 0.001

0.002
2014
Lindane

0.0002

0.000032
1999
(rev2005)
Methoxychlor

0.03 0.01

0.00009
2010
Molinate

0.02 0.002

0.001
2008
Oxamyl

0.05 0.02

0.026
2009
Pentachlorophenol

0.001

0.0002

0.0003
2009
Picloram

0.5 0.001

0.166
2016
Polychlorinated biphenyls (PCBs)

0.0005

0.00009
2007
Simazine

0.004

0.001

0.004
2001
Thiobencarb

0.07 0.001

0.042
2016
Trichlorofluoromethane (FC-11)

0.15 0.00015

1.3 2014
Toxaphene

0.003

0.001

0.00003
2003
1,2,3-Trichloropropane

0.000005

0.0000007
2009
2,3,7,8-TCDD (dioxin)
3x108
5x10-6
5x10-8
2010
2,4,5-TP (Silvex)

0.05 0.001

0.003
2014

Chemicals with MCLs in 22 CCR §64533 —Disinfection Byproducts Total Trihalomethanes 0.080
--
--
--
Bromodichloromethane
--

0.0010

0.00006
2020
Bromoform
--

0.0010

0.0005
2020
Chloroform
--

0.0010

0.0004
2020
Dibromochloromethane
--

0.0010

0.0001
2020
Haloacetic Acids (five) (HAA5)

0.060
--
--
--
Monochloroacetic Acid
--

0.0020

0.053
2022
Dichloroacetic Adic
--

0.0010

0.0002
2022
Trichloroacetic Acid
--

0.0010

0.0001
2022
Monobromoacetic Acid
--

0.0010

0.025
2022
Dibromoacetic Acid
--

0.0010

0.00003
2022
Bromate

0.010

0.0050**

0.0001
2009
Chlorite

1.0 0.020

0.05 2009
Chemicals soon to be regulated in drinking water in California N-Nitrosodimethylamine (NDMA)
--
--

0.000003
2006
Perfluoroctanoic acid (PFOA)
--
--

0.000000007
2024
Perfluorooctane Sulfonic acid (PFOS)
--
--

0.000001
2024
Perfluorohexane sulfonic acid (PFHxS)
--
--
--
--
Perfluorononanoate (PFNA)
--
--
--
--
2,3,3,3-Tetrafluoro-2-(heptafluoropropoxy)propanoate
(HFPO-DA or GenX Chemicals)
PFAS Hazard Index (includes HFPO-DA, PFBS,
PFHxS, and PFNA)
--
--
--
--
Chemicals with PHGs established in response to DDW requests. These are not currently regulated drinking water contaminants.

N-Nitrosodimethylamine (NDMA)
F--
--

0.000003
2006
*OEHHA's review of this chemical during the year indicated (rev20XX) resulted in no change in the PHG. **The DLR for Bromate is 0.0010 mg/L for analysis performed using EPA Method 317.0 Revision 2.0, 321.8, or 326.0.

k,
I
s

Prevent PoLLution
Polluted runoff flows tnstorm drains directly into our rivers, bays, beaches, and the ocean. Contaminated runoff can pollute our beaches, and also harm fish and wildlife. As a community it is important to prevent chemicals, automobile fluid, and trash from entering our storm drains.
��
��
Aoassessment ofthe Cby'sdrinking water sources was completed in2003by the State Department ofDrinking Water. The sources are considered most vulnerable to the following activities: automobile gas stations, dry cleaners, injection wells, dry wells, sumps, finishing, fabricating, metal plating, fleet truck, bus terminals, furniture repair, manufacturing, machine shops, and National Pollutant Discharge Elimination System (NPDES)/ Waste Discharge Requirement permitted discharges. A copy of the complete assessment is available by contacting the State Water Resources Control Board (SVVVCB), Division of Drinking Water (DDW) at (818) 551-2004 or by calling the City of Downey Utilities Division at(s62)9U«-7ZO2.

YOUR ER SUPPLY
Dmmneytgroundwater ispumped from the Central
Groundwater Basin. The Central Basin is series of
large natural aquifers below the ground that stretch
from Los Angeles toOrange County.

The City ofDowney conveniently overlies the Central
Basin. 6mundwate,komthe Central Basin ispumped
from 20welts located within the City'sboundaries
and provides the City with its principal source of
potable water. The [ity'sservice area is shown onthe
map mthe left.

The Central Basin receives natural inflows from the
conservation of rainfall and snow melt, artificial
inflows from imported and recycled water, axwell
as groundwater underfiow from adjacent basins.

Surface water slowly percolates through the ground
tnthe aquifers and the ground acts asanatural filter
tuclean the water.

Trained water distribution
1 Wes

Protecting I
Water from
Did you kno "77,
Common hazards in and around
your house can contaminate your
drinking water? The City's Public
Works Department Utilities Division,
through its Backftow Prevention
Program, goes to great lengths to
protect the water entering your home.

However, we need your help to protect
the water on your home's property.

Avoid putting the gard(a
or buckets to fill. Wat
can flow back into I
!cose aTcl iTto voijr Kii-tt .

Protect Your Home With Air Vacuum Breakers
Over half of the Nation's cross -connections involve
unprotected garden hoses. Check to see if you have air
vacuum breakers installed on each of your hose bibbs. They prevent water from getting back into the drinking water system. These simple devices are inexpensive and can be purchased from your local hardware store. They are easy to install, you just simply screw them onto the hose bibb.

Avoid connecting your
garden hose to a plant
This can cause harmful
chemicals to flow back
into your home.

OPIUM=
when it's backed up. This can
cause a serious health hazard.

Contaminated water can be
drawn back into your home's
watersupply.

TOILET HAS ALEAK
X(Blue water in bowl)
N/
How to Check, Your Water Meter
Quick Method to Detect Toilet Leaks
Toilet leaks maybe easy tnrepair, but detecting them can beachaUenge.Here bavery quick and easy method tohelp you detect atoilet leak.
z: Take off the tank lid.
2; Add 10 drops of food coloring liquid or a commercially available blue leak detector tablet into tank,
3: Wait 15uo 2Ominutes (do not flush the toilet)
4: Check toilet bmwi|fthere iscolored water inthe toilet bowl, you have aleak! Awater meter isadevice that measures the volume ofwater delivered tuaproperty.

Checking the water meter can help you determine ifthere isawater teak. (Note: Moke sure no woter is being used inside or outside your home while performing this test). 1: Locate yourwater meter box and carefully remove the lid, (Be cautious minsects mothermatl animals). 2; Check your water meter tosee ifthe flow indicator nrsweep hand ismoving, 3; A moving leak indicator or sweep hand showsthat water is either being used orwasted. 4: 8esure tosecurely reattach the meter lid tnprevent trip hazards. 5; |fleak isdetected, repair teak within 48hours.

DuhngZ0Z2 metested our water for over lU0regulated contaminants insdertudetenminethe pesenceufany biological, inorganic, volatile organic or synthetic organic, and radioactive contaminants. The following table includes those contaminants that were detected in the water. Bothhederaiand state regulations require us to monitor for certain substances less than once per year because the concentrations of these substances do not change frequently. |nthese cases, the most recent sample data are included.

City �of Downey �2022 Ground Water z
_
Barium (ppm) 1 2 IND ND - 0.11 NO Discharge of oil drilling wastes and from metal refineries; erosion of natural deposits
,er use; leaching from septic
turat deposits
)m some surface water
Alkalinity (ppm) n/a n/a 167.5 120-220 NO Naturally occurring soluble mineral Calcium (ppm) n/a n/a 80.8 511-111.0 NO Abundant naturally occurring element Magnesium (ppm) n/a n/a 15.9 9.8 - 223 NO Abundant naturally occurring element pH (units) (6.5-8.5) n/a 74 6.9-7.8 NO Hydrogen ion concentration n/a n/a 4.4 3.5-4.9 NO Runoff or teaching from natural deposits "Hardness" is the sum of polyvalent cations present in the water, Total Hardness (grains per gallon) n/a n/a 15.6 9.8-21.5 NO generally magnesium and calcium. The cations are usually naturally occurring

City oDowney 2022 Distribution System Water Data
Lead (ppb) 15 0.2 3.9 0 out of 50 NO Internal corrosion of household wat from industrialmanufacturers; erosi
ng systems; discharges
Manganese (ppb) (50) n/a 0.19 ND - 2.0 NO Leaching from natural deposits Perfluorooctanesulfonic Acid (PFOS) (ppt) n/a n/a 27.5 16-41 NO Perfluorohexan`esulfonic`Acid (PFHxS)(ppt)' n/a n/a 6.0 3.1-78 NO Perfluoroheptanoicacid l(PFHpA)(ppt) n/a n/a 2.9 ND-4.8 NO GLos ary of Terms/Abbreviations
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 ZMCLGs) as is economically and technologically feasible. Secondary MCLs CLs) are set to protect 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 bythe U.S. EPA.

Detection Limits for Purposes of Reporting (DLR): The DLR is a parameter that is set by regulation by each reportable analyte. It is not laboratory specific and it is independent of the analytical method used (in cases where several methods are approved). It is expected that a laboratory can achieve a Reporting Limit that is lower than or equal to the DLR set by the State. This is also known as the Minimum Reporting Level (MRL).

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

EoifEdiAlkes:

1. The State allows us to monitor for some contaminants less than once per year because the concentrations of these contaminants do not change frequently. In these cases the most recent data available is used.

2. 1,2,3-Trichloropropane (1,2,3-TCP): During the 2020 - 2022 compliance period the City was required to collect two quarterly samples from each well in one calendar year. Due to an oversight, our water system failed to complete the required number of 1,2,3-TCP samples and only collected samples for one of the two required quarters resulting in a monitoring violation. However, for the one quarter of samples that were collected, results indicated Non -Detect (ND). At the beginning of 2023, after being notified of the violation, the City conducted 1,2,3-TCP sampling as a proactive measure and results again indicated NO Even though all (1,2,3-TCP) samples collected from the City's wells have been ND to date, some people who do drink water containing 1,2,3-Trichloropropane in excess of the MCL over many years may have an increased risk of getting cancer. You as the consumer should be aware of any adverse health risk associated with this contaminant.

In addition to notifying consumers in the 2022 CCR of the monitoring violation and the potential health risks, the City will correctthe violation by collecting an additional two consecutive quarters of samples in 2023, The City also implemented a new monitoring scheduling system which will help prevent this type of situation in the future.

Public Health Goal (PHG): The level of a contaminant in drinking water NTU: Nephelometric Turbidity Units
below which there is no known or expected risk to health. PHGs are set by the California Environmental Protection Agency,
Units of Measurement:

Regulatory Action Level: (AL): The concentration of a contaminant which, if ppm: parts per million
exceeded, triggers treatment or other requirements that a water system must ppb: parts per billion
follow.
ppt: parts per tri Ilion
Notification levels (NLs): Are nonregulatory, health -based advisory levels established for contaminants in drinking water for which maximum pCi/L: picocuries per liter
contaminant levels have not been established.
µS/cm: micro Siemens per centimeter
Response Level (RL): is set higher than a notification level and represents a %: percent
recommended chemical concentration level at which water systems consider taking a water source out of service or provide treatment if that option is available to them.
n/a: Not Applicable.

ND: Contaminant was not detected. The contaminant is less than the DLR.

3. There are no PHGs, MCLGs, or mandatory health effects language for these constituents because secondary MCLs are set on the basis of aesthetics.

4. Lead and Copper testing results are based on triennial monitoring within residential taps. Results are based on 2020 monitoring.

5. Data from City of Downey Wells were collected from Jan. 1, 2018 to Dec.31, 2020 for Unregulated Chemical Monitoring Rule 4. Unregulated contaminant monitoring helps USEPA and the State Water Resources Control Board to determine where certain contaminants occur and whether the contaminants need to be regulated.

6. On August 27, 2020, the Division of Drinking Water (DDW) issued General Order DW-2020-0003-DDW for the testing of 18 PFAS to expand on the data collected from previous monitoring of PEAS ordered in 2019. Four Quarters of data were collected from the City of Downey's water wells in 2022, On February 6, 2020 the DDW issued Notification Levels (NLs) and Response Levels (RLs) for Perfluorooctanoic acid (PFOA) of 5.1 plat and 10 plat and for Perfluorooctane sulfonic Acid (PFOS) of 6.5 plat and 40 ppt. In addition, on March 5, 2021, an NL of 500 opt and an RL 5,000 opt were added for Perfluorobutane satanic acid (PFBS). Lastly on October 31, 2022, an NL of 3 ppt and an RL of 20 pptwere added forperfluorohexane suffouic acid (PFHxS).

PEAS monitoring helps the USEPA and the State Water Resources Control Board (SWRCB) to determine where certain contaminants occur and whether the contaminants need to be regulated,

lmr)ortant infonniation
This report contains important
information about your drinking water.

Please contact the City of Downey
Public Water System at 562-904-7202
for assistance.

Este informe contiene informaci6n
muy importante sobre su agua para
beber. Favor de comunicarse con City of
Downey Water System al numero 562-
904-7202 para asistirlo en espahot.

Ang pag-uutat na ito ay nagtalaman ng
ma-halagang impormasyon tungkol
sa inyong inuming tubig. Mangyaring
makipag-ugnayan sa City of Downey
Water System o tumawag sa 562-904-7202
para matutungan sa wikang Tagalog.
o :_7 ,,] I - r-
jj->> All 2[�i tj- � _2_
V,
—" City of Downey
PubLic Involvement
You are welcome to attend the
following public meetings at City
Hall, 11111 Brookshire Ave.

City Council Meetings
Held on the second and fourth Tuesday
of each month at 6:30 p.m.

Public Works Committee Meetings
Held on the third Thursday of each
month at 4:00pm.

11 YOUR ER SUPPLY
Downey's groundwater ispumped from the Central
Groundwater Basin. The Central Basin isaseries /f
large natural aquifers below the ground that stretch
from Los Angeles toOrange County.

The City ofDowney conveniently overlies the Central
Basin. Gmundwate,hnmthe Central Basin ispumped
from 20welts located within the City's boundaries
and provides the City with its principal source of
potable water. The City's service area isshown onthe
map tuthe left.

The Central Basin receives natural inflows from the
conservation of rainfall and snow melt, artificial
inflows from imported and recycled water, as well
as groundwater underRow from adjacent basins.

Surface water slowly percolates through the ground
tothe aquifers and the ground acts asanatural filter
toclean the water.

Tra~r�ied water distribution
IM

Protecting
�Ut€ IIII I€flIIII I€III III I€OI€VI III IIII I€WI€ V I III I I N I II I II III I It I I I I I I It I I I I I I I I I I I I I I I I I t I I t I I I I I I I I I I I W I I W I I I I I t I I I I I I I W I I W I I W I I W I IW I I W IU� Protect Your Home With Air Vacuum Breakers
Over half of the Nation's cross -connections involve
unprotected garden hoses. Check to see if you have air _ vacuum breakers installed on each of your hose bibbs. They prevent water from getting back into the drinking water system. These simple devices are inexpensive and can be purchased from your local hardware store. They are easy to install, you just simply screw them onto the hose bibb. �1191EBIEEIEEIEWIEE6&g(EBdEEd&g(fiW(WB(WB(fillWikflg(VI€WIIWI1816W1€WIt81(WI611IE88kIlIf VI€EIRfl1EVIf VIE01€WI&WIEWI€WIf VI(WI€NIfWIVWIWtlIS" Did you kno
1 ti
Common hazards in and around
your house can contaminate your --t
drinking water? The City's Public
Works Department Utilities Division, Avoid putting the garden Avoid connecting your through its Backflow Prevention hose into swimming pools garden hose to a plant Program, goes to great lengths to or buckets to fill. Water fertilizer or bug spray unit. protect the water entering your home. can flow back into the This can cause harmful However, we need your help to protect hose and into your home. chemicals to flow back the water on your home's property. into your home.
.01 RM . .=
backedwhen it's

TOILET HAS ALEAK
X (Blue water in bowl) V
How to Check Your Water Meter
Quick Method to Detect ToRet Leaks
Toilet leaks maybe easy torepair, but detecting them can beadha8enge.Here bavery quick and easy method tohelp you detect atoilet leak.
z: Take off the tank lid.
2; Add 10 drops of food coloring liquid ora commerciattyavaitab[e blue leak detector tablet into tank,
3: Wait 15uo 2Ominutes (do not flush the toilet)
4: Check toilet bowl. |fthere iscolored water inthe toilet bowl, you have aleak! Awater meter badevice that measures the volume of water delivered tuaproperty.

Checking the water meter can help you determine ifthere isawater leak. (Note: Moke sure no woter is being used inside or outside your home while performing this test). 1: Locate yourwater meter box and carefully remove the lid, (Be cautious minsects mothermatl animals). 2: Check your water meter tosee ifthe flow indicator nrsweep hand ismoving, 3' A moving leak indicator or sweep hand showsthat water is either being used orwasted. 4; 8esure tosecurely reattach the meter lid toprevent trip hazards. 5; |fleak isdetected, repair teak within 48hours.

�� Testing
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During 2023 metested our water for over lU0regulated contaminants inmderindetenninethe pesenceufany biological, inorganic, volatile organic or synthetic organic, and radioactive contaminants. The following table includes those contaminants that were detected in the water. Bothhederaiand state regulations require us to monitor for certain substances less than once per year because the concentrations of these substances do not change frequently. |nthese cases, the most recent sample data are included.

City of Downey 2023 Ground Water Data:'
Gross Alpha Particle Activity (pCi/L) 15 (0) N D ND - 6.01 NO Erosion of natural deposits Manganese (ppb) (50) n/a ND ND - 8.5 NO Leaching from natural deposits Odor (Units) (3) n/a 1 ND - 10 NO Naturally occurring organic materials Total Dissolved Solids (ppm) (1000) n/a 498 270-610 NO Runoff/leaching from natural deposits Alkalinity (ppm)
n/a
n/a
168
120-220
NO
Naturally occurring soluble mineral
Calcium (ppm)
n/a
n/a

80.2 40.9-111.0
NO
Abundant naturally occurring element
Magnesium (ppm)
n/a
n/a

15.9 &0 - 22.3
NO
Abundant naturally occurring element
pH (units)
(6.5-8.5)
n/a

7.5 6.9-7.8
NO
Hydrogen ion concentration
Potassium (ppm)
n/a
n/a

4.4 3.5-4.9
NO
Runoff or leaching from natural deposits
Sodium (ppm)
n/a
n/a

59.5 39.0-77.0
NO
Erosion of natural deposits
"Hardness" is the sum of polyvalent cations present in the water, Total Hardness (grains per gallon)
n/a
n/a

15.5 7.9-21.5
NO
generally magnesium and calcium. The cations are usually naturally occurring

City of Downey23 Distribution System Water Data
Manganese (ppb) (50) n/a 0.19 NO 2.0 NO Leaching from natural deposits Perfluorooctanesulfonic Acid (PFOS) (ppt) n/a n/a 28.4 17.3 42.8 NO Perfluorohexanesulfonic Acid (PFHxS) (ppt) n/a n/a 5.5 2.3 75 NO Perfluoroheotanoic acid'(PFHoA) (oot) n/a n/a 2.3 ND 4.5 NO Perfluoropentanoic acid (PFPeA) (ppt) n/a n/a 9.4 ND 22.5 NO Glossary of "i er€rts/AE; breraiations
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 (SMCLs) are set to protect 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.

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

1. The State allows us to monitorfor some contaminants less than once per year because the concentrations of these contaminants do not change frequently. In these cases the most recent data available is used.

2. There are no PHGs, MCLGs, or mandatory health effects language for these constituents because secondary MCLs are set on the basis of aesthetics.

3. Lead and Coppertesting results are based on triennial monitoring within residential taps. Results are based on 2020 monitoring.

4. Data from City of Downey Wells were collected from Jan. 1, 2018 to Dec.31, 2020 for Unregulated Chemical Monitoring Rule 4. Unregulated contaminant monitoring helps USEPA and the State Water Resources Control Board to determine where certain contaminants occur and whetherthe contaminants need to be regulated.

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.

Notification levels (NLs): Are nonregutatory, health -based advisory levels established for contaminants in drinking water for which maximum contaminant levels have not been established.

Response Level (RL): is set higher than a notification level and represents a recommended chemical concentration level at which water systems consider taking a water source out of service or provide treatment if that option is available to them.
n/a: Not Applicable.

ND: Contaminant was not detected. The contaminant is less than the DLR.

5. On Ocotber 31, 2022, the Division of Drinking Water (DDW) issued General Order DW-2022-0001-DDW for the testing of 25 PFAS to expand on the data collected from previous monitoring of PFAS ordered in 2020. Four Quarters of data were collected from the City of Downey's water wells in 2023. On February 6, 2020 the DDW issued Notification Levels (NLs) and Response Levels (RES) for Perfluorooctanoic acid (PFOA) of 5.1 plot and 10 opt and for Perfluorooctane sulfuric Acid (PFOS) of 6.5 plot and 40 plot. In addition, on March 5, 2021, an NIL of 500 opt and an RL 5,000 opt were added for Perfluorobutane sulfonic acid (PFBS). Lastly on October 31, 2022, an N L of 3 potandan RL of20 pot were added forperfluorohexane sulfonic acid (PFHxS).

PFAS monitoring helps the USEPA and the State Water Resources Control Board (SWRCB) to determine where certain contaminants occur and whetherthe contaminants need to be regulated.

NTU: Nephelometric Turbidity Units
Units of Measurement:
ppm: parts per million
ppb: parts per billion
ppt: parts per tri pion
pCi/L: picocuries per titer
pS/cm: micro Siemens per centimeter
%: percent

Important Information
This report contains important
information about your drinking water.

Please contact the City of Downey
Public Water System at 562-904-7202
for assistance.

Este informe contiene informaci6n
muy importante sobre su agua para
beber. Favor de comunicarse con City of
Downey Water System at numero 562-
904-7202 para asistirto en espanot.

Ang pag-uutat na ito ay nagtalaman ng
ma-hatagang impormasyon tungkol
sa inyong inuming tubig. Mangyaring
makipag-ugnayan sa City of Downey
Water System o tumawag sa 562-904-7202
para matulungan sa wikang T1agalog.
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s,- --f 1 S-- 91 o]- 1,1 1,11 City of Downey
Public InvoLvenient
You are welcome to attend the
following public meetings at City
Hall, 11111 Brookshire Ave.

City Council Meetings
Held on the second and fourth Tuesday
of each month at 6:30 p.m.

Public Works Committee Meetings
Held on the third Thursday of each
month at 4:00pm.

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Prevent PoLLution
Polluted runoff flows tostorm drains directly into our rivers, bays, beaches, and the ocean. Contaminated runoff can pollute our beaches, and also harm fish and wildlife. Asacommunity itisimportant toprevent chemicals, automobile fluid, and trash from entering our storm drains. ��
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An assessment of the Otys drinking water sources was completed in 2003 by the State Division of Drinking Water. The sources are considered most vulnerable to the following activities: automobile gas stations, dry cleaners, injection wells, dry wells, sumps, finishing, fabricating, metal plating, fleet truck, bus terminals, h/mhne repair, manufacturing, machine shops, and National Pollutant Discharge Elimination System (NposS)/Wage Discharge Requirement permitted discharges. A copy of the complete assessment is available by contacting the State Water Resources Control Board (3VVR[B)` Division of Drinking Water (DDVV) at (818) 551'2004 or by calling the City of Downey Utilities Division at(s62)904-7Z02.
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Downey's groundwater is pumped from the Central
Groundwater Basin. The Central Basin is a series of
large natural aquifers below the ground that stretch
from Los Angeles to Orange County.

The City of Downey conveniently overlies the Central
Basin. Groundwaterfrom the Central Basin is pumped
from 20 wells located within the City's boundaries
and provides the City with its principal source of
potable water. The City's service area is shown on the
map to the left.

The Central Basin receives natural inflows from the
conservation of rainfall and snow melt, artificial
inflows from imported and recycled water, as well
as groundwater underfloor from adjacent basins.

Surface water slowly percolates through the ground
to the aquifers and the ground acts as a natural filter to clean the water.
'41,01,111,f }i"'M
files of Potable
Water Main
@Pll �� C S�R�jIi 3i it thy.

Water Meters
Isolation Valves
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It 2III s:

NJ in
Fire Hydrants

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Common hazards in and amund �M
your house can contaminate your
drinking water? The [ity's Public
Works Department Utilities Division, Avoid putting the garden Avoid connecting your through its BackOow Prevention hose into swimming pools garden hose to a plant Program, goes to great lengths to or buckets to fill. Water fertilizer orbug spray unit. protect the water entering your home. can flow back into the This can cause harmful However, weneed your help tuprotect hose and into your home. chemicals to flow back the water onyour home's property. into your home.
'"I'MM owl 11
when it's backed up. This can
cause a serious health hazard.

Contaminated water can be
drawn back into your home's

TOILET RAS A LEAK
X (Blue water in bowl) V
How to Check te�i"Meter
Quick Metitod to Detect �,;�;i Let L.eaks
Toilet leaks maybe easy to repair, but detecting them can be a ch a ttenge. Here is a very quick and easy method to help you detect a toilet leak.
1: Take off the tank lid.
2: Add 10 drops of food coloring liquid or commercially available blue leak detector tablet into tank.
3: Wait 15 to 20 minutes (do not flush the toilet)
4: Check toilet bowl. If there is colored water in the toilet bowl, you have a leak! A water meter is a device that measures the volume of water delivered to a property.

Checking the water meter can help you determine if there is a water teak. (Note: Make sure no water is being used inside or outside your home while performing this test). 1: Locate your water meter box and carefully remove the lid. (Be cautious of insects orothersmatl animals). 2: Check your water meter to see if the flow indicator or sweep hand is moving, 3: A moving leak indicator or sweep hand shows that water is either being used or wasted. 4: Be sure to securely reattach the meter lid to prevent trip hazards. 5: If leak is detected, repair teak within 48 hours.

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During Z024wetested our water for over lU0regulated contaminants inmdertudetenminethepesenceufanybiologicaLinorgpnic,vnbdlenrganic or synthetic organic, and radioactive contaminants. The following table includes those contaminants that were detected in the water. Bothhederaiand state regulations require us to monitor for certain substances less than once per year because the concentrations of these substances do not change frequently. |nthese cases, the most recent sample data are included.

City of Downey 2024 Ground Water Data'
Gross Alpha Particle Activity (pCi/Q 15 (0) ND ND - 5.73 NO Erosion of natural deposits Tetra c h to roethylene (PCE) (ppb) 5 0.06 ND ND - 1.14 NO Discharge from factories, dry cleaners, and auto shops (metal Arsenic (ppb) 10 0.004 ND NO - 2.5 NO Erosion of natural deposits; runoff from orchards; glass and electronics production wastes
Fluoride (ppm) 2 1 0.31 0.25-0.35 NO Erosion of natural deposits; water additive which promotes strong teeth; discharge from fertilizer and aluminum factories �
Chloride (ppm) (500) n/a 91 38-120 NO Runoff and teaching of natural deposits ^ - ^
Manganese (ppb) (50) n/a ND ND - 8.5 NO Leaching from natural deposits Specific Conductance (pS/cm)
(1600)
n/a
818 480-960 NO Substances that form ions when in water; seawater influence Sulfate (ppm)
(500)
n/a
112 65-160 NO Runoff/teaching from natural deposits; industrial wastes Total Dissolved Solids (ppm)
(1000)
n/a
491 270-610 NO Runoff/teaching from natural deposits
Alkalinity, Bicarbonate (ppm) n/a n/a 206 140-270 NO Naturally occurring soluble mineral Magnesium (ppm) n/a n/a 15.9 8.0-22.3 NO Abundant naturally occurring element Potassium (ppm) n/a n/a 4.5 3.5-4.9 NO Runoff or teaching from natural deposits "Hardness" is the sum of potyvalent cations present in the water, Total Hardness (grains per gallon) n/a n/a 15.7 7.9-21.5 NO generally magnesium and calcium. The cations are usually naturally occurring

City of Downey 2024 Distribution
Lead (ppb) 15 0.2 2.8 0 out of 50 NO Internal corrosion of household water plumbing systems; discharges from industrial manufacturers; erosion of natural deposits Manganese (ppb) (50) n/a 0.19 NO 2.0 NO Leaching from natural deposits PerfluorooctanesulfonicAcid (PFOS) (ppt) n/a n/a 29.5 14.5 45.8 NO Perfluorohexanesulfonic Acid (PFHxS) (ppt); n/a n/a 4.8 ND 7:7 NO Perfluoroheptanoic acid (PFHpA) (ppt) n/a n/a 1 ND 4.8 NO Perfluoropentanoic acid (PFPeA) (ppt) n/a n/a 11.5 ND - 22 NO G ossary of Terms/Abbreviations
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 ZMCLGs) as is economically and technologically feasible. Secondary MCLs CLs) are set to protect 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.

Detection Limits for Purposes of Reporting (DLR): The DLR is a parameter that is set by regulation by each reportable analyte. It is not laboratory specific and it is independent of the analytical method used (in cases where several methods are approved). It is expected that a laboratory can achieve a Reporting Limit that is lower than or equat to the DLR set by the State. This is also known as the Minimum Reporting Level (MRL).

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

1. The State allows us to monitor for some contaminants less than once oeryear because the concentrations of these contaminants do not change frequently. In these cases the most recent data available is used.

2. There are no PHGs, MCLGs, or mandatory health effects language for these constituents because secondary MCLs are set on the basis of aesthetics.

3. Lead and Copper testing results are based on triennial monitoring within residential taps. Results are based on 2023 monitoring.

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.

Notification levels (NLs): Are nonregulatory, health -based levels established for contaminants in drinking water for which contaminant levels have not been established.

ND: Contaminant was not detected. The contaminant is less than the DLR.

5. On Ocotber 31, 2022, the Division of Drinking Water (DDW) issued General Order DW-2022-0001-DDW for the testing of 25 PEAS to expand on the data collected from previous monitoring of PEAS ordered in 2020. Four Quarters of data were collected from the City of Downey's water wells in 2024, On February 6, 2020 the DDW issued Notification Levels (NLs) and Response Levels (RLs) for Perfluorooctanoic acid (PFOA) of 5.1 opt and 10 pot and for Perfluorooctane sulfonic Acid (PFOS) of 6.5 opt and 40 opt. In addition, on March 5, 2021, an NL of 500 opt and an RL 5,000 opt were added for Perfluorobutane sulfonic acid (FEES). Lastly on October 31, 2022, an NL of 3 ppt and an RL of 20 pot were added for perfluorohexane sulfonic acid (PFHxS).

PEAS monitoring helps the USEPA and the State Water Resources Controt Board (SWRCB) to determine where certain contaminants occur and whether the contaminants need to be regulated.

NTU: Nephelometric Turbidity Units

Important Information
This report contains important
information about your drinking water.

Please contact the City of Downey
Public Water System at 562-904-7202
for assistance.

Este informe contiene informaci6n
muy importante sobre su agua para
beber. Favor de comunicarse con City of
Downey Water System at numero 562-
904-7202 para asistirto en espahot.

Ang pag-uutat na ito ay naglalaman ng
ma-hatagang impormasyon tungko[
sa inyong inuming tubig. Mangyaring
makipag-ugnayan sa City of Downey
Water System o tumawag sa 562-904-7202
para matutungan sa wikang Tagalog.
ol 1�
City ofDowney
PubLic InvoLvement
You are welcome to attend the
following public meetings at City
Halt, 11111 Brookshire Ave.

City Council Meetings
Held on the second and fourth Tuesday
of each month at 6:30 p.m.

Public Works Committee Meetings
Held on the third Thursday of each
month at 4:00pm.

Downey City CouncilJune 9, 2026

Downey City Council
June 9, 2026