Form 8-K

8-K — CALIFORNIA WATER SERVICE GROUP

Accession: 0001104659-26-053556

Filed: 2026-05-01

Period: 2026-04-30

CIK: 0001035201

SIC: 4941 (WATER SUPPLY)

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K — tm2613168d2_8k.htm (Primary)

EX-99.1 — EXHIBIT 99.1 (tm2613168d2_ex99-1.htm)

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

Current Report Pursuant to Section 13

or 15(d) of

The Securities Exchange Act of 1934

Date of Report (date of earliest event

reported): April 30, 2026

CALIFORNIA WATER SERVICE GROUP

(Exact name of Registrant as Specified in its

Charter)

Delaware

(State or other jurisdiction

of incorporation)

1-13883

(Commission file number)

77-0448994

(I.R.S. Employer

Identification Number)

1720 North First Street

San Jose, California

(Address of principal executive offices)

95112

(Zip Code)

(408) 367-8200

(Registrant’s telephone number, including

area code)

N/A

(Former name or former address, if changed

since last report)

Check the appropriate box below if the Form 8-K filing

is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act

(17 CFR 240.14d-2(b))

Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act

(17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of

the Act:

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common Shares, par value $0.01

CWT

New York Stock Exchange

Indicate by check mark whether the registrant is an emerging

growth company as defined by Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of

the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ¨

If an emerging growth

company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or

revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

Item 8.01.

Other Events

On April 30, 2026, California Water Service Group

(Group) issued a press release (a copy of which is attached hereto as Exhibit 99.1 and incorporated herein by reference) announcing the

California Public Utilities Commission’s final decision on the 2024 General Rate Case of California Water Service, Group’s

largest subsidiary.

Item 9.01.

Financial Statements and Exhibits.

(d) Exhibits.

We hereby file the following exhibit with this

report:

Exhibit No.

Description

99.1

Press Release issued April 30, 2026

104

Cover Page Interactive Date File (embedded within the Inline XBRL document)

SIGNATURES

Pursuant to the requirements of the Securities

Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

CALIFORNIA WATER SERVICE GROUP

Date: May 1, 2026

By:

/s/ James P. Lynch

Name:

James P. Lynch

Title:

Senior Vice President, Chief Financial Officer and Treasurer

EX-99.1 — EXHIBIT 99.1

EX-99.1

Filename: tm2613168d2_ex99-1.htm · Sequence: 2

Exhibit 99.1

DATE:

April 30, 2026

MEDIA

CONTACT: Yvonne Kingman, (310) 257-1434

For

Immediate Release

California

Public Utilities Commission Issues Decision in California Water

Service’s 2024 General Rate Case, Infrastructure Improvement Plan

SAN

JOSE, Calif.—California Water Service (Cal Water), the largest subsidiary of California Water Service Group (Group) (NYSE: CWT),

received a final decision on its 2024 General Rate Case and Infrastructure Improvement Plan from the California Public Utilities Commission

(CPUC) on April 30, 2026. The Company believes the decision enables Cal Water to invest responsibly in water system infrastructure

through 2027 to support its communities and sets Cal Water’s revenue and rates to help sustain safe, clean, reliable water service

through 2028.

The

CPUC adopted the proposed decision (PD) issued March 13, 2026 with revisions issued on April 29, 2026 (revised PD). The final

decision increases Cal Water’s company-wide revenues by $90.5 million in 2026 (a rate increase of 10.9%), $43.2 million in 2027

(a rate increase of 4.7%), and $48.9 million in 2028 (a rate increase of 5.1%). The differences between approved revenue and rate increases

in the PD and the revised PD are primarily attributable to a reduction in authorized capital, some of which is now subject to the CPUC’s

advice letter process discussed below Cal Water is currently analyzing how the final decision will impact rates in each of its service

areas.

The

decision also authorizes Cal Water to invest $1.45 billion in its districts from 2024 through 2027 to upgrade infrastructure, such as

water quality projects to protect customers from existing and newly regulated contaminants; pipes and other infrastructure to keep pumping

and delivering water reliably; equipment to keep water flowing during power outages and shutoffs; cyber and physical security improvements

to protect employees, customers, and facilities; and water supply initiatives to secure long-term sustainability of water sources. It

authorizes up to $229 million in additional projects that will be submitted for recovery through the CPUC’s advice letter process.

Although

the decision does not allow full decoupling, it does renew the Monterey-style Water Revenue Adjustment Mechanism and water production

incremental cost balancing accounts. It also establishes a new sales reconciliation mechanism that allows Cal Water to adjust sales forecasts

annually, and it approves a rate design to better enable the company to recover fixed costs regardless of water sales. The mechanisms,

balancing accounts, and new rate design provide financial stability while supporting customer affordability, particularly for low-income,

low-water-using customers.

“We

recognize the criticality of keeping water service affordable while making the infrastructure investments needed to provide safe, clean,

reliable water to our communities,” said Martin A. Kropelnicki, Group Chairman and CEO. “We appreciate the CPUC for issuing

the final decision in our triennial General Rate Case and Infrastructure Improvement Plan and enabling us to continue providing quality,

service, and value to our customers and communities for their everyday and emergency needs.”

This

marks the end of a required, extensive, nearly two-year review of the company’s water system improvement plans, costs, and rates.

Cal Water expects to implement the new rates effective July 1, 2026.

About

California Water Service Group

Group

is the parent company of regulated utilities California Water Service, Hawaii Water Service, New Mexico Water Service, and Washington

Water Service, as well as Texas Water Service (TWSC, Inc.), a utility holding company. Together, these companies provide regulated

and non-regulated water and wastewater service to more than 2.2 million people in California, Hawaii, New Mexico, Washington, and Texas.

Group’s common stock trades on the New York Stock Exchange under the symbol “CWT.” Additional information is available

online at www.calwatergroup.com.

This

news release contains forward-looking statements within the meaning established by the Private Securities Litigation Reform Act of 1995

(“PSLRA”). The forward-looking statements are intended to qualify under provisions of the federal securities laws for “safe

harbor” treatment established by the PSLRA. Forward-looking statements in this news release are based on currently available information,

expectations, estimates, assumptions and projections, and our management’s beliefs, assumptions, judgments and expectations about

us, the water utility industry and general economic conditions. These statements are not statements of historical fact. When used in

our documents, statements that are not historical in nature, including words like will, would, expects, intends, plans, believes, may,

could, estimates, assumes, anticipates, projects, progress, predicts, hopes, targets, forecasts, should, seeks or variations of these

words or similar expressions are intended to identify forward-looking statements. Examples of forward-looking statements in this news

release include, but are not limited to, statements describing Group’s beliefs, expectations, and plans related to the CPUC’s

final decision on the 2024 GRC and related impacts on Group’s business. Forward-looking statements are not guarantees of future

performance. They are based on numerous assumptions that we believe are reasonable, but they are open to a wide range of uncertainties

and business risks. Consequently, actual results or outcomes may vary materially from what is contained in a forward-looking statement.

Factors that may cause actual results or outcomes to be different than those expected or anticipated include but are not limited to the

risks described under the section entitled “Risk Factors” and elsewhere in our most recent Annual Report on Form 10-K

and our other SEC filings. In light of these risks, uncertainties and assumptions, investors are cautioned not to place undue reliance

on forward-looking statements, which speak only as of the date of this news release. We are not under any obligation, and we expressly

disclaim any obligation, to update or alter any forward-looking statements, whether as a result of new information, future events or

otherwise.

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