On March 4, the Fremont City Council approved the Lake Elizabeth Water Quality Improvement Pilot Project. This pilot project is being implemented to reduce the likelihood of fish die-off events occurring during extreme heat, like the one that occurred in July 2024. In response to that event, the City hired an environmental consultant. After a thorough investigation, the consultant determined that the fish die-off was caused by extreme heat and shallow lake depth, leading to low dissolved oxygen concentrations and elevated lake water temperatures.
The Lake Elizabeth Water Quality Improvement Pilot Project will install the following elements to a section of the lake to determine their effectiveness at reducing the likelihood of future fish die-offs: three surface aerators for improved oxygenation; nine floating islands for shade and temperature regulation; and three continuous probes for water quality monitoring. The goal is to install these elements by July 2025, at a total estimated cost of $175,000. If the pilot project is successful, the City may consider expanding the project to additional sections of the lake. Additional project benefits may include cooler lake temperatures, better oxygen levels, and reduced algae growth.
Lake Elizabeth, located in Fremont’s Central Park, is an 83-acre freshwater lake designed for flood control and stormwater storage. The lake is owned by the Alameda County Flood Control and Water Conservation District (ACFCD) and licensed to the City for recreational purposes. According to ACFCD, the lake’s current depth is adequate for flood protection purposes, so dredging is not warranted at this time.