

On August 15th, the City of Oakland set in motion a new chapter in the fight against Harmful Algal Blooms (HAB) in Lake Merritt with the Lake Merritt Water Quality Management Pilot Project. Installing a new aeration fountain, the initiative aims to create a healthier environment for the lake's fish and wildlife, responding to issues that arose in 2022 after an HAB event, according to the as mentioned in the City of Oakland Twitter post. The project signals a growing need to address the challenges presented by HABs—a phenomenon that can carry wide-reaching negative consequences for ecosystems, recreation, and even human health.
On August 15th, Oakland Public Works installed a new aeration fountain on Lake Merritt—one piece of an ongoing effort to maintain healthy conditions for fish and wildlife at the Lake. Read more here! https://t.co/gXQizOuYBl pic.twitter.com/VhOC9lTCIU
— City of Oakland (@Oakland) August 22, 2023
While last year's HAB, caused by the species Heterosigma akashiwo, may be a thing of the past, the threat of these blooms remains very real, as per KRON4. In a concerning development, the species was once again detected in the San Francisco Bay on August 1st, according to the City of Oakland news report. Although the recent bloom has largely dissipated, summer weather and changing conditions mean that the possibility of new blooms loom on the horizon.
With an understanding of the challenges at hand, Oakland's new aeration fountain located near the Pergola by El Embarcadero Avenue seeks to improve the dissolved oxygen levels in Lake Merritt by mixing air into the water. The fountain, which replaces an out-of-service one at the same location, is designed to provide an oxygenated refuge for aquatic life while maximizing benefits to the ecosystem.
However, the aeration fountain is only one aspect of the Lake Merritt Water Quality Management Pilot Project. By early September, a second device for increasing dissolved oxygen will be installed in the Glen Echo arm of the lake near the intersection of Grand and Harrison Avenue. Unlike the visible fountain, this device will sit on the bottom of the lake and release oxygen directly into the water.
While these oxygenation devices alone cannot prevent HABs, they are an essential tool in creating a comprehensive approach to mitigating their impact on the lake. Alongside the physical installations, the Pilot project also includes continuous monitoring of dissolved oxygen and other water quality parameters, a review of prior water quality data collected by others, a stakeholder engagement meeting held in January, and a recommendations report to guide future work according to the City of Oakland report.
Initiating a project of this magnitude requires collaboration and support from a wide range of organizations. Among them are the Alameda County Flood Control and Water Conservation District, the U.S. Army Corps of Engineers, the California Department of Fish and Wildlife, the East Bay Municipal Utility District, the Lake Merritt Institute, the Measure DD Community Coalition, the Oakland Parks and Recreation Foundation, the San Francisco Bay Regional Water Quality Control Board, and the San Francisco Estuary Project as per the City of Oakland.