Our Work

Our Work

Leona Quarry Revegetation

Leona Quarry Revegetation

H. T. Harvey & Associates restoration ecologists and landscape architects prepared the conceptual revegetation design and detailed construction documents for restoring a functional plant-soil ecosystem on 40 acres of steep, rocky, denuded quarry slopes and along Chimes Creek at the century-old, abandoned Leona Quarry in Alameda County, California. The project’s revegetation success stands as a model for using ecological science to inform a collaborative restoration design and construction efforts.

Our team of expert ecologists and landscape architects conducted baseline soils and vegetation studies and collaborated with the project's engineering team and construction contractors to successfully integrate innovative topsoil preparation techniques into the grading and habitat restoration plans and construction documents. The design also included phased seeding and planting with native coastal scrub and grassland species over several years and the development of irrigation techniques for steep harsh slopes. The team developed, created, and monitored a pilot revegetation site and learned from its successes over the multiple years of project installation. We provided bid support and construction oversight for preparing soils; installing irrigation, fencing, and trails; revegetating the project area; and maintaining plants to ensure establishment.

After construction, our restoration ecologists conducted five years of annual vegetation monitoring and utilized the monitoring results to adaptively guide vegetation maintenance activities. The site met all of its final success criteria in year five. Reviewers at the State Office of Mines and Geology lauded the state-of-the-art restoration plan and the construction documents we prepared. Our restoration ecologists published the lessons learned from our long-term monitoring in the Ecological Restoration Journal. Busnardo, M. et al. 2017. Techniques to Restore Coastal Scrub at a Reclaimed Quarry in Central California. Ecological Restoration Journal.34:354-361.