In the 1950’s, the Utah Corporation created five connected lagoons along the southwest shoreline of Alameda, between the original coast and the new South Shore Development.
The South Shore Lagoon system brings in salt-water from the San Francisco Bay and supports diverse wildlife.
Although the lagoons are privately owned and can be used for recreational uses by the adjacent property owners and members of the Alameda West Lagoon Homeowners' Association (AWLHOA), the lagoon system is also a storm drainage retention and treatment pond for portions of Alameda Island.
The South Shore Lagoon system is divided into segments:
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Lagoon 1: Westline to Grand
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Lagoon 2: Grand to Willow
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Lagoon 3: Willow to Park
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Lagoon 4: Park to Broadway
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Lagoon 5: Broadway to Court

Lagoon Maintenance
To view the North Shore Dock spec and South Dock Spec drawings, click
here.
The lagoons are drained once a year in order to perform annual maintenance work. Lagoon lowering is scheduled to commence April 4, 2022. There will be a longer lowering than usual for Lagoons 3, 4, and 5 in order to accommodate much-needed repairs to the concrete columns of the Bayview Weir in Lagoon 5 (Lagoons 3, 4, and 5 can be isolated from the rest of the system) and are planned to remain down through July 13, 2022 to accommodate the 60-working day window. Repair work may not take this full time frame and the lagoons will be raised earlier if work completes before this date. Lagoons 1 and 2 are able to be raised separately using the Willow Street Weir and can be raised earlier and have a more normal lowering time. Lagoons 1 and 2 are tentatively scheduled to remain down through May 16, 2022.
The planned schedule for 2022 is as follows:
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Monday, April 4, 2022: start lowering lagoons
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Monday, April 18, 2022: end of draining
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Wednesday, June 13, 2022: start refilling lagoons
If debris and plant matter are collected during this maintenance period, please place the material in sturdy garbage bags and place at curbside. Public Works provides weekly curbside pickup.
Water Quality
The Public Works Departments and the AWLHOA are jointly responsible for maintaining the water quality. Inspection and debris removal is performed weekly. Water quality of the lagoons is monitored through use of indicator bacteria. You can view test results on the AWLHOA
To control algal blooms and widgeon grass, aquatic pesticide treatments are applied under the regulatory authority of the Regional Water Board. Here is the City’s notice of intent(PDF, 89KB) per the Statewide General National Pollutant Discharge Elimination System Permit for Residual Aquatic Pesticide Discharges to Waters of the United States from Algae and Aquatic Weed Control Application. The City’s Aquatic Pesticide Application Plan(PDF, 1MB) (APAP) describes the project site, aquatic plant and algae nuisances, aquatic pesticide products expected to be used, the monitoring program, and Best Management Practices to be followed. The use of aquatic pesticides within the Alameda Lagoons is necessary to manage the lake and maintain the beneficial uses that include storm water retention, fishing, swimming, boating, aesthetics, and a habitat and resting place for waterfowl and migratory birds.
To submit a comment, question or service request on any of the lagoons within this system, please do so here.
