HomeMy WebLinkAboutItem 23 - Public Hearing Public Works Water Quality Report and Public Health Goals Public Works Agency
www.santa-ana.org/pw
Item # 23
City of Santa Ana
20 Civic Center Plaza, Santa Ana, CA 92701
Staff Report
November 4, 2025
TOPIC: Public Works Water Quality Report and Public Health Goals
AGENDA TITLE
Public Hearing – Approve the Report on Water Quality Relative to the Public Health
Goals for Public Distribution
Legal notice published in the OC Reporter on October 24, 2025.
RECOMMENDED ACTION
Approve the City of Santa Ana 2025 Public Health Goals Report for Public Distribution.
GOVERNMENT CODE §84308 APPLIES: No
DISCUSSION
The Public Works Agency Water Resources Division (PWA) operates and maintains the
City’s water and sanitary sewer systems. The water system is comprised of
approximately 480 miles of water main, 21 groundwater wells, seven pump stations, 10
reservoirs with a storage capacity of 49 million gallons, four pressure regulating
stations, and seven connection points to Metropolitan Water District. The system has an
average daily demand of 30 million gallons from its roughly 45,500 metered service
connections.
Background
Public water systems are highly regulated to ensure the safety and reliability of drinking
water. The United States Environmental Protection Agency (USEPA) establishes
Maximum Contaminant Levels (MCLs) for various substances to protect public health.
All public water systems, including the City of Santa Ana’s, must comply with these
stringent federal standards.
In addition, the California Environmental Protection Agency’s Office of Environmental
Health Hazard Assessment (OEHHA) establishes Public Health Goals (PHGs) for
contaminants in drinking water. PHGs represent aspirational targets, set at
concentrations far lower than MCLs, that public water systems are encouraged, but not
required, to meet. Achieving PHGs may be technically feasible; however, doing so is
often impractical due to the high cost and limited public health benefits relative to
existing standards.
Report on Water Quality Relative to the Public Health Goals
November 4, 2025
Page 2
5
4
0
9
Public Health Goal Report
Pursuant to the California Health and Safety Code Section 116470, the City must
prepare a report every three years identifying instances where detected contaminants in
drinking water exceed PHGs (Exhibit 1). The report is then forwarded to the State Water
Resources Control Board, Division of Water (DDW) for use in revising or developing an
MCL in drinking water. For calendar years 2022 through 2024, the City’s drinking water
exceeded PHGs for naturally occurring elements, such as arsenic, radium, uranium,
hexavalent chromium, gross alpha particle activity, and gross beta particle activity, as
well as for bromate, perchlorate, perfluorooctanesulfonic acid (PFOS), and
perfluorooctanoic acid (PFOA).
Importantly, the City’s drinking water continues to meet or exceed all federal and state
drinking water standards established by the USEPA, DDW. These standards are
designed to ensure water safety and protect public health.
The report also provides cost estimates for implementing the best available treatment
technologies to reduce these contaminants further, such as ion exchange and reverse
osmosis. The estimated annual cost to achieve PHG levels ranges from $14.1 million to
$99.5 million, which would impose an extraordinary financial burden on the community.
Given the substantial costs and the fact that the City’s water meets all mandatory health
and safety standards, no additional treatment programs are proposed at this time.
In accordance with state law, the City is required to hold a public hearing to receive and
respond to comments on the PHG report prior to making available for public distribution.
This hearing fulfills that statutory requirement. Once approved, Staff will submit a copy
to DDW and publish the report on the City’s website.
ENVIRONMENTAL IMPACT
There is no environmental impact associated with the action.
FISCAL IMPACT
There is no fiscal impact associated with the action.
EXHIBIT(S)
1. City of Santa Ana Report on Water Quality Relative to Public Health Goals
Submitted By: Rodolfo Rosas, P.E., Acting Executive Director – Public Works Agency
Approved By: Alvaro Nuñez, City Manager
CITY OF SANTA ANA
2025 PUBLIC HEALTH GOALS REPORT
JUNE 2025
2025 Public Health Goals (PHGs) Report
City of Santa Ana
1.0 Introduction
Under the Calderon-Sher Safe Drinking Water Act of 1996 public water systems in California
serving greater than 10,000 service connections must prepare a report containing information
on 1) detection of any contaminant in drinking water at a level exceeding a Public Health Goal
(PHG), 2) estimate of costs to remove detected contaminants to below the PHG using Best
Available Technology (BAT), and 3) health risks for each contaminant exceeding a PHG. This
report must be made available to the public every three years. The initial PHGs Report was due
on July 1, 1998, and subsequent reports are due every three years thereafter.
The 2025 PHGs Report has been prepared to address the requirements set forth in Section
116470 of the California Health and Safety Code. It is based on water quality analyses during
calendar years 2022, 2023, and 2024 or, if certain analyses were not performed during those
years, the most recent data is used. The 2025 PHGs Report has been designed to be as
informative as possible, without unnecessary duplication of information contained in the
Consumer Confidence Report (also known as Water Quality Report), which is provided to
customers by July 1 of each year.
There are no regulations explaining requirements for the preparation of PHGs reports.A
workgroup of the Association of California Water Agencies (ACWA) Water Quality Committee
has prepared suggested guidelines for water utilities to use in preparing PHGs reports. The
ACWA guidelines were used in the preparation of this 2025 PHGs Report. These guidelines
include tables of cost estimates for BAT. The State of California (State) provides ACWA with
numerical health risks and category of health risk information for contaminants with PHGs. This
health risk information is appended to the ACWA guidelines.
2.0 California Drinking Water Regulatory Process
California Health and Safety Code Section 116365 requires the State to develop a PHG for
every contaminant with a primary drinking water standard or for any contaminant the State is
City of Santa Ana 1 2025 PHGs Report
proposing to regulate with a primary drinking water standard. A PHG is the level of a
contaminant in drinking water that poses no significant health risk if consumed for a lifetime.
The process of establishing a PHG is a risk assessment based strictly on human health
considerations. PHGs are recommended targets and are not required to be met by any public
water system.
The State office designated to develop PHGs is the California Environmental Protection
Agency’s Office of Environmental Health Hazard Assessment (OEHHA). The PHG is then
forwarded to the State Water Resources Control Board, Division of Drinking Water (DDW) for
use in revising or developing a Maximum Contaminant Level (MCL) in drinking water. The MCL
is the highest level of a contaminant that is allowed in drinking water. State MCLs cannot be
less stringent than federal MCLs and must be as close as is technically and economically
feasible to the PHGs. DDW is required to take treatment technologies and cost of compliance
into account when setting an MCL. Each MCL is reviewed at least once every five years.
Two radiological contaminants (gross alpha particle activity and gross beta particle activity)
have MCLs but do not yet have designated PHGs. For these contaminants, the Maximum
Contaminant Level Goal (MCLG), the federal U.S. Environmental Protection Agency (USEPA)
equivalent of PHGs, is used in the 2025 PHGs Report.
3.0 Identification of Contaminants
Section 116470(b)(1) of the Health and Safety Code requires public water systems serving
more than 10,000 service connections to identify each contaminant detected in drinking water
that exceeded the applicable PHG. Section 116470(f) requires the MCLG to be used for
comparison if there is no applicable PHG.
The City of Santa Ana (City) water system has approximately 45,652 service connections. The
following constituents were detected at one or more locations within the drinking water system
at levels that exceeded the applicable PHGs or MCLGs:
Arsenic – naturally-occurring in local groundwater.
City of Santa Ana 2 2025 PHGs Report
Bromate – formed when naturally-occurring bromide reacts with ozone during the
disinfection process in treated surface water purchased from the Metropolitan Water
District of Southern California (MWDSC).
Gross alpha particle activity (gross alpha) – naturally-occurring in local groundwater
and in treated surface water purchased from MWDSC.
Gross beta particle activity (gross beta) – naturally-occurring in treated surface water
purchased from MWDSC; not required to be tested in local groundwater.
Hexavalent Chromium – naturally-occurring in local groundwater.
Perchlorate – industrial contamination in local groundwater.
Perfluorooctanesulfonic acid (PFOS) – industrial contamination in local groundwater.
Perfluorooctanoic acid (PFOA) – industrial contamination in local groundwater.
Radium, Combined, is the sum of Radium-226 and Radium-228 – naturally-occurring in
treated surface water purchased from MWDSC.
Uranium – naturally-occurring in local groundwater and in treated surface water
purchased from MWDSC.
The accompanying table shows the applicable PHG or MCLG and MCL for each contaminant
identified above. The table includes the maximum, minimum, and average concentrations of
each contaminant in drinking water supplied by the City in calendar years 2022 through 2024.
4.0 Numerical Public Health Risks
Section 116470(b)(2) of the Health and Safety Code requires disclosure of the numerical public
health risk, determined by OEHHA, associated with the MCLs, PHGs and MCLGs. Available
numerical health risks developed by OEHHA for the contaminants identified above are shown
on the accompany table. Only numerical risks associated with cancer-causing chemicals have
been quantified by OEHHA.
Arsenic – OEHHA has determined the health risk associated with the PHG is 1 excess case of
cancer in a million people and the risk associated with the MCL is 2.5 excess cases of cancer in
1,000 people exposed over a 70-year lifetime.
City of Santa Ana 3 2025 PHGs Report
Bromate – OEHHA has determined the health risk associated with the PHG is 1 excess case of
cancer in a million people and the risk associated with the MCL is 1 excess case of cancer in
10,000 people exposed over a 70-year lifetime.
Gross Alpha – OEHHA has not established a PHG. USEPA has established an MCLG of 0.
USEPA has determined the risk associated with the MCL is 1 excess case of cancer in 1,000
people exposed over a 70-year lifetime for the most potent alpha emitter.
Gross Beta – OEHHA has not established a PHG. USEPA has established an MCLG of 0.
USEPA has determined the risk associated with the MCL is 2 excess cases of cancer in 1,000
people exposed over a 70-year lifetime for the most potent beta emitter.
Hexavalent Chromium – OEHHA has determined the health risk associated with the PHG is 1
excess case of cancer in a million people and the risk associated with the MCL is 5 excess
cases of cancer in 10,000 people exposed over a 70-year lifetime.
Perchlorate – OEHHA has not established a numerical health risk for perchlorate because
PHGs for non-carcinogenic chemicals in drinking water are set at a concentration at which no
known or anticipated adverse health risks will occur, with an adequate margin of safety.
PFOS – OEHHA has determined the health risk associated with the PHG is 1 excess case of
cancer in a million people. There is no California MCL for PFOS; therefore, the risk information
associated with the MCL is not available/applicable.
PFOA – OEHHA has determined the health risk associated with the PHG is 1 excess case of
cancer in a million people. There is no California MCL for PFOA; therefore, the risk information
associated with the MCL is not available/applicable.
Radium, Combined – OEHHA has determined that the health risk associated with the PHG is 1
excess case of cancer in one million people over a 70-year lifetime exposure; and the risk
associated with the MCL is 1 excess case of cancer in 10,000 people for radium-226 and 3
excess cases of cancer in 10,000 people for radium-228 over a 70-year lifetime exposure.
City of Santa Ana 4 2025 PHGs Report
Uranium – OEHHA has determined the health risk associated with the PHG is 1 excess case of
cancer in a million people and the risk associated with the MCL is 5 excess cases of cancer in
100,000 people exposed over a 70-year lifetime.
5.0 Identification of Risk Categories
Section 116470(b)(3) of the Health and Safety Code requires identification of the category of
risk to public health associated with exposure to the contaminant in drinking water, including a
brief, plainly worded description of those terms. The risk categories and definitions for the
contaminants identified above are shown on the accompanying table.
6.0 Description of Best Available Technology
Section 116470(b)(4) of the Health and Safety Code requires a description of the BAT, if any is
available on a commercial basis, to remove or reduce the concentrations of the contaminants
identified above. The BATs are shown on the accompanying table.
7.0 Costs of Using Best Available Technologies and Intended Actions
Section 116470(b)(5) of the Health and Safety Code requires an estimate of the aggregate cost
and cost per customer of utilizing the BATs identified to reduce the concentration of a
contaminant to a level at or below the PHG or MCLG. In addition, Section 116470(b)(6)
requires a brief description of any actions the water purveyor intends to take to reduce the
concentration of the contaminant and the basis for that decision.
Arsenic – The BATs for removal of arsenic in water for large water systems are: activated
alumina, coagulation/filtration, electrodialysis, ion exchange, lime softening, oxidation/filtration,
and reverse osmosis. Arsenic was detected above the PHG in the local groundwater (Well 37).
The City is in compliance with the MCL for arsenic. The estimated cost to reduce arsenic levels
in the groundwater to below the PHG of 0.004 microgram per liter (µg/l) using ion exchange was
calculated. Because the DDW detection limit for purposes of reporting (DLR) for arsenic is 2
µg/l, treating arsenic to below the PHG level means treating arsenic to below the DLR of 2 µg/l.
There are numerous factors that may influence the actual cost of reducing arsenic levels to the
City of Santa Ana 5 2025 PHGs Report
PHG. Achieving the water quality goal for arsenic could be approximately $2,610,000 per year,
or $57 per service connection per year.
Bromate – The BATs for removal of bromate in water for large water systems are:
coagulation/filtration optimization, granular activated carbon, and reverse osmosis. Bromate
was detected above the PHG in the treated surface water purchased from MWDSC. The City is
in compliance with the MCL for bromate. The estimated cost to reduce bromate levels in
MWDSC water to below the PHG of 0.1 µg/l using reverse osmosis was calculated. Because
the DLR for bromate is 1 µg/l, treating bromate to below the PHG level means treating bromate
to below the DLR of 1 µg/l. There are numerous factors that may influence the actual cost of
reducing bromate levels to the PHG. Achieving the water quality goal for bromate could range
from approximately $2,020,000 to $17,300,000 per year, or between $44 and $379 per service
connection per year.
Gross Alpha, Gross Beta, Combined Radium, and Uranium – The only BAT for the removal
of gross alpha in water for large water systems is reverse osmosis, which can also remove
gross beta, combined radium, and uranium, if detected. Gross alpha was detected above the
MCLG in the local groundwater (Wells 18, 20, 21, 24, 26, 29, 30, 35, 36, 37, 39, 40, and 41) and
treated surface water purchased from MWDSC. Gross beta was detected above the MCLG in
the treated surface water purchased from MWDSC. Combined radium was detected above the
MCLG in the treated surface water purchased from MWDSC. Uranium was detected above the
PHG in the local groundwater (Wells 18, 20, 21, 24, 30, 33, 35, 36, 37, 39, 40, and 41) and
treated surface water purchased from MWDSC. The cost of providing treatment using reverse
osmosis to reduce gross alpha levels to the MCLG of 0 picoCurie per liter (pCi/l) (and
consequently gross beta to below the MCLG of 0 pCi/l, combined radium to below the MCLG of
0 pCi/l, and uranium in to below the PHG of 0.43 pCi/l) was calculated. Because the DLR for
gross alpha is 3 pCi/l, treating gross alpha to 0 pCi/l means treating it to below the DLR of 3
pCi/l (and treating gross beta, radium-226, radium-228, and uranium to below their respective
DLRs of 4 pCi/l, 1 pCi/l, 1 pCi/l, and 1 pCi/l). Achieving the water quality goal for gross alpha
could range from $10,500,000 to $89,800,000 per year, or between $230 and $1,970 per
service connection per year.
Hexavalent Chromium – The BATs for removal of hexavalent chromium in water for large
water systems are: ion exchange, reduction/coagulation/filtration, and reverse osmosis.
City of Santa Ana 6 2025 PHGs Report
Hexavalent chromium was detected above the PHG in the local groundwater (Wells 18, 20, 21,
24, 26, 29, 30, 33, 34, 35, 36, 37, 39, 40, and 41). The City is in compliance with the MCL for
hexavalent chromium. The estimated cost to reduce hexavalent chromium levels in the
groundwater to below the PHG of 0.02 µg/l using reduction/coagulation/filtration was calculated.
Because the DLR for hexavalent chromium is 0.1 µg/l, treating hexavalent chromium to below
the PHG level means treating hexavalent chromium to below the DLR of 0.1 µg/l. There are
numerous factors that may influence the actual cost of reducing hexavalent chromium levels to
the PHG. Achieving the water quality goal for hexavalent chromium could be approximately
$17,800,000 to $111,000,000 per year, or between $390 and $2,440 per service connection per
year.
Perchlorate – The BATs for removal of perchlorate in water for large water systems are ion
exchange and biological fluidized bed reactor. Perchlorate was detected above the PHG in the
local groundwater (Wells 18, 20, 21, 24, 26, 30, 35, 36, and 39). The City is in compliance with
the MCL for perchlorate. The estimated cost to reduce perchlorate levels in the groundwater to
below the PHG of 1 µg/l using ion exchange was calculated. Because the DLR for perchlorate
is 1 µg/l, treating perchlorate to below the PHG level means treating perchlorate to below the
DLR of 1 µg/l. There are numerous factors that may influence the actual cost of reducing
perchlorate levels to the PHG. Achieving the water quality goal for perchlorate could be
approximately $3,370,000 to $7,400,000 per year, or between $74 and $162 per service
connection per year.
PFOS and PFOA – The BATs for removal of PFOS and PFOA in water for large water systems
are: granular activated carbon, ion exchange, and reverse osmosis. PFOS and PFOA were
detected above their respective PHGs in the local groundwater (Wells 18, 24, 26, 29, 33, 36, 39,
40, and 41). The City is in compliance with the State requirements for PFOS and PFOA. The
estimated cost to reduce PFOS and PFOA levels in the groundwater to below their respective
PHGs of 1 nanogram per liter (ng/l) and 0.007 ng/l using ion exchange was calculated.
Because the DDW Consumer Confidence Report Detection Level (CCRDL) for PFOS and
PFOA is 4 ng/l, treating PFOS and PFOA to below their respective PHG levels means treating
PFOS and PFOA to below the CCRDL of 4 ng/l. There are numerous factors that may influence
the actual cost of reducing PFOS and PFOA levels to their respective PHGs. Achieving the
water quality goal for PFOS and PFOA could be approximately $4,450,000 to $60,800,000 per
year, or between $97 and $1,330 per service connection per year.
City of Santa Ana 7 2025 PHGs Report
All Contaminants – In addition, a cost estimate to treat all water produced by the City using ion
exchange and reverse osmosis to remove all the contaminants detected above the PHGs or
MCLGs was calculated. All the contaminants listed in the accompanying table may be removed
to non-detectable levels by ion exchange and reverse osmosis.As shown on the
accompanying table, achieving the water quality goals for all contaminants using ion exchange
and reverse osmosis could range from $14,100,000 to $99,500,000 per year, or between $309
and $2,180 per service connection per year.
For additional information, please contact the Water Resources Division at
Waterinfo@santa-ana.org, or write to the City of Santa Ana, 220 S. Daisy Avenue, Santa
Ana, California 92703
J:\2605\2605-004 - Santa Ana 2025 PHG\Santa Ana_2025 PHG_text_Final.docx
City of Santa Ana 8 2025 PHGs Report
2025 PUBLIC HEALTH GOALS REPORT
CITY OF SANTA ANA
UNITS
OF
MEASUREMENT
PHG
OR
(MCLG)*
MCL DLR
OR
(CCRDL)
CONCENTRATION CATEGORY CANCER RISK CANCER BEST
AVAILABLE
TECHNOLOGIES
AGGREGATE
COST
PER YEAR
COST PER
SERVICE CONNECTION
PER YEAR
PARAMETER AVERAGE RANGE OF AT PHG RISK
RISK OR MCLG AT MCL
INORGANIC CHEMICALS
Arsenic μg/l
μg/l
μg/l
μg/l
0.004
0.1
10
10
10
6
2
1
ND
ND
0.7
ND
ND - 2.5
ND - 7.6
0.29 - 2.3
ND - 3.3
C
C
C
E
1 x 10-6
1 x 10-6
1 x 10-6
NA
2.5 x 10-3
1 x 10-4
5 x 10-4
NA
AA,C/F,E,IE,LS,O/F,RO
C/F, GAC, RO
IE, R/C/F, RO
$2,610,000 (a)$57 (a)
Bromate $2,020,000 - $17,300,000 (b)
$17,800,000 - $111,000,000 (c)
$3,370,000 - $7,400,000 (d)
$44 - 379 (b)
$390 - $2,440 (c)
$74 - $162 (d)
Hexavalent Chromium
Perchlorate
0.02
1
0.1
1 IE, BFBR
ORGANIC CHEMICALS
Perfluorooctanesulfonic Acid (PFOS)
Perfluorooctanoic Acid (PFOA)
ng/l
ng/l
1 4 **
4 **
(4)
(4)
ND
ND
ND - 22 ***
ND - 15 ***
C
C
1 x 10-6
1 x 10-6
(e)
(e)
GAC, IE, RO
GAC, IE, RO
$4,450,000 - $60,800,000 (f)
--
$97 - $1,330 (f)
--0.007
RADIOLOGICAL
Gross Alpha Particle Activity pCi/l (0)15
50
3 ND
ND
ND - 5
ND - 9
C 0 1 x 10-3
2 x 10-3
3 x 10-4
5 x 10-5
RO $10,500,000 - $89,800,000 (g)$230 - $1,970 (g)
Gross Beta Particle Activity
Radium, Combined (h)
pCi/l
pCi/l
(0)
(0)
4 C
C
0 IE, RO --
--
--
--1 (h)1 x 10-6
1 x 10-6
IE, LS, RO5ND
2
ND - 1
Uranium pCi/l 0.43 20 1 ND - 5.8 C
--
IE, RO, LS,C/F
IE and RO
----
ALL CONTAMINANTS ----------------$14,100,000 - $99,500,000 (i)$309 - $2,180 (i)
* MCLGs are shown in parentheses. MCLGs are provided only when no applicable PHG exists.
** Federal MCL
*** Range of detections reported before the effective Federal MCL compliance date of April 26, 2029.TREATMENT TECHNOLOGIES
AA = Activated Aluminum
BFBR = Biological fluidized Bed Reactor
C/F = Coagulation/Filtration
E = Electrodialysis
RISK CATEGORIES
C (Carcinogen) = A substance that is capable of producing cancer.
E (Endocrine Toxicity and Developmental Toxicity) = A substance that can affect the thyroid or cause neurodevelopmental deficits.
GAC = Granular Activated Carbon
IE = Ion ExchangeNOTES
CCRDL = Consumer Confidence Report Detection Level
DLR = Detection Limit for Purposes of Reporting
MCL = Maximum Contaminant Level
MCLG = Maximum Contaminant Level Goal
μg/l = micrograms per liter or parts per billion
NA = Not Applicable
LS = Lime Softening
O/F = Oxidation/Filtration
R/C/F = Reduction/Coagulation/Filtration
RO = Reverse Osmosis
ND = Not Detected
ng/l = nanograms per liter or parts per trillion
pCi/l = picoCuries per liter
PHG = Public Health Goal
(a) Estimated cost to remove arsenic using IE.
(b) Estimated cost to remove bromate using RO.
(c) Estimated cost to remove hexavalent chromium using R/C/F.
(d) Estimated cost to remove perchlorate using IE.
(e) Not applicable. Cancer risk cannot be calculated.
(f) Estimated cost to remove PFOS and PFOA using IE.
(g) Estimated cost to remove gross alpha particle activity using RO, which also removes combined radium, gross beta particle activity, and uranium.
(h) As the sum of radium-226 and radium-228. DLRs for radium-226 and radium-228 is 1 pCi/L and 1 pCi/L, respectively.
(i) Assuming treating the entire production by IE and RO, which can remove all contaminants listed in the above table to below the detectable levels.
J:\2605\2605-004 - Santa Ana 2025 PHG\Santa Ana_phgtable_2025_Final.xlsx