Granite Construction (GVA) said Wednesday it has secured a $31 million contract from Hydrostor for pre-construction work at the clean-energy technology company's flagship energy storage facility in California.

Under the award, Granite will undertake early site infrastructure work for the planned 500-megawatt Willow Rock Energy Storage Center, a compressed-air energy storage facility capable of powering more than 400,000 homes for up to eight hours.

Granite began its early works grading phase in July and expects to complete it in March.