UC Davis Hypolimnetic Oxygenation System Pilot Program (Lake Alteration Agreement EPIMS Notification No. LAK-64924-R2)

The University of California Davis is authorized under Lake Alteration Agreement EPIMS Notification Number LAK-64924-R2 to install a temporary hypolimnetic oxygenation system in Clear Lake to enhance dissolved oxygen levels and support native fish populations. The system consists of two submerged pipelines, each 20,000 linear feet long, extending from a pier adjacent to the Clearlake Oaks County Water District’s treatment plant, looping around the west end of Rattlesnake Island, and terminating in the deepest portion of Oaks Arm. The pipelines will be assembled onshore, floated into place, and then anchored to the lakebed using concrete weights without any excavation or permanent alteration to the shoreline or lakebed. The diffuser lines will remain suspended one to three feet above the bottom during operation to ensure effective oxygen distribution while minimizing disturbance to aquatic sediments. The oxygen gas will be delivered via compressed air from the water district’s adjacent property, with no new infrastructure constructed on land or in the lake beyond the pipelines and anchors. The system is designed as a pilot program with no permanent structures, and all components will remain temporary. The California Department of Fish and Wildlife has approved the project under Section 1602 of the Fish and Game Code to ensure compliance with environmental protections. The project is managed by Alexander Tremblay at UC Davis and overseen by Will Kanz, an Environmental Scientist with the California Department of Fish and Wildlife, Region 2.