Exhibit 99.1

​

Orion Group Holdings, Inc. Announces Retirement of Two Board Members and Decrease in Board Size

​

HOUSTON—March 17, 2026--Orion Group Holdings, Inc. (NYSE: ORN) (the "Company") a leading specialty construction company, today announced that Thomas (“Tom”) N. Amonett, who has served as an independent member of the Company’s Board of Directors (the “Board”) and Audit Committee since 2007 and Chairman of the Nominating & Governance Committee from 2007 to 2025, informed the Company that he has chosen not to stand for re-election and instead retire from the Board effective at the Company’s upcoming Annual General Meeting of Stockholders on May 19, 2026.

​

The Company also announced that Margaret (“Peggy”) M. Foran, who has served as an independent member of the Board since 2019, Chairman of the Compensation Committee from 2019 to 2025 and Chairman of the Nominating & Governance Committee since 2025 (and a member of the Nominating & Governance Committee since 2019), informed the Company that she has chosen not to stand for re-election and instead retire from the Board effective at the Company’s upcoming Annual General Meeting of Stockholders on May 19, 2026.

​

Effective upon Mr. Amonett’s and Ms. Foran’s retirements, the Board has determined to reduce its size from eight directors to six directors.

​

Austin Shanfelter, the Company’s Chairman of the Board, commented, “We want to thank Tom and Peggy for their years of service to the Company and their many valuable contributions, including their leadership of the Nominating and Governance Committee. Tom has been a steady hand on the Board over the years, and we will miss his strategic mind and sound advice. Meanwhile, Peggy has served as our governance expert and we will miss her legal acumen and public company insights. We wish them all the best in their future endeavors.”

​

Mr. Amonett stated, “It has been my distinct honor to serve on this Board for 19 years and as Chairman of the Nominating and Governance Committee for almost that whole time. I am proud of the tremendous transformation the Company has achieved over this time, and I leave with great confidence in Orion’s future and the strength of its Board.”

​

Ms. Foran stated, “I have thoroughly enjoyed my time on the Board over the past six years. The management team and the Board are strong and the Company is well positioned to capture the growth opportunities ahead. I wish the management team and my fellow Board members all the best.”

​

v3.26.1

Document and Entity Information	Mar. 16, 2026
Document and Entity Information [Abstract]
Document Type	8-K/A
Document Period End Date	Mar. 16, 2026
Entity File Number	1-33891
Entity Registrant Name	ORION GROUP HOLDINGS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	26-0097459
Entity Address, Address Line One	2940 Riverby Road,
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Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77020
City Area Code	713
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Pre-commencement Tender Offer	false
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Title of 12(b) Security	Common stock, $0.01 par value per share
Trading Symbol	ORN
Security Exchange Name	NYSE
Entity Emerging Growth Company	false
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