The Oro Loma Horizontal Levee Project is a multi-agency and multi-jurisdictional project combining the expertise of numerous project partners to address multiple functions for the Oro Loma wastewater treatment facility. The project converted a 10-acre field along the San Francisco Bay’s edge into an eight-million gallon holding basin connected to a horizontal levee. Water from the wastewater treatment plant will be further treated by the vegetation in the holding basin and through microbial uptake as it passes through the horizontal levee before entering the Bay. The system also serves to protect the wastewater treatment facility from sea level rise.