Granite (NYSE:GVA) announced today that it has been awarded an approximately $31 million Early Works Grading Package by Hydrostor for its Willow Rock Energy Storage Center (WRESC) Project, located north of Rosamond in Kern County, California. The award will be included in Granite’s third quarter 2026 CAP.

The Willow Rock Energy Storage Center is a planned 500 MW Advanced Compressed Air Energy Storage (A-CAES) facility in the Mojave Desert, capable of powering more than 400,000 homes for eight hours.

Granite’s scope includes construction of early site infrastructure on the 89-acre project site, including a nine-acre pad to support the subsurface contractor’s work to drill and excavate a 1.3-million-cubic-yard cavern approximately 2,000 feet below the surface. Additional work includes offsite road improvements, onsite stormwater basins, and laydown areas for subsurface mining materials and topside EPCM contractors staging materials for construction of the four-turbine energy storage facility.

“This award aligns with Granite’s strategic focus on growing specialized private-sector work with clients that value construction expertise, collaboration, and problem-solving,” said Darryl Ebel, Granite Area Manager. “We are proud to bring our Bakersfield team’s site development experience to a project designed to support California’s long-term energy storage needs.”

“Hydrostor is thrilled to start pre-construction work on-site in Kern County for our flagship U.S. energy storage facility, which will support thousands of jobs locally and help to ensure a reliable California grid for decades to come. Partnering with an organization like Granite will help us set the stage for successful project delivery, as they bring their industry leading expertise to the site,” said Josh Rowan, Senior Vice President of Project Execution at Hydrostor.

Granite’s early works grading phase of the project began in July 2026 and is planned to conclude in March 2027.

For more information about the project, visit Hydrostor’s Willow Rock Energy Storage Center project page.

About Granite

Granite is America’s Infrastructure Company™. Incorporated since 1922, Granite (NYSE:GVA) is one of the largest diversified construction and construction materials companies in the United States as well as a full-suite civil construction provider. Granite’s Code of Conduct and strong Core Values guide the Company and its employees to uphold the highest ethical standards. Granite is an industry leader in safety and an award-winning firm in quality and sustainability. For more information, visit the Granite website, graniteconstruction.com, and connect with Granite on LinkedIn, X, Facebook, and Instagram.