Most people who rent a boat on Lake Chabot don't know they're paddling on a piece of 19th-century infrastructure. The lake was built in 1874-75 as a primary source of water for the East Bay, and it was closed to the public for 91 years. Today it is an East Bay Regional Park District park, though the water still has a job to do.

A reservoir first

The lake was formed by damming San Leandro Creek. It was originally called the San Leandro Reservoir and was renamed Lower San Leandro Reservoir after a second dam upstream created Upper San Leandro Reservoir. The American Society of Civil Engineers named Chabot Dam a California Historic Civil Engineering Landmark in 1976.

Construction had a side effect that is still visible. According to Wikipedia, much of the dam's clay core and soil was washed away in a storm during construction in 1874, and the sediment helped form Arrowhead Marsh at the mouth of San Leandro Creek near Oakland International Airport. That marsh is now one of the last remaining wetlands in the East Bay, part of Martin Luther King Jr. Regional Shoreline.

Opened in 1966

Legislation in the 1960s allowed controlled recreation, and on June 18, 1966, the park district opened Lake Chabot Regional Park under an agreement with EBMUD, which still owns and operates the reservoir. The lake now serves as a standby emergency water supply, which is why visitors are asked to follow rules that keep the water clean.

Know before you go

  • No swimming, ever. The park district says swimming is never permitted at Lake Chabot.
  • Algae advisory. A danger advisory for blue-green algae was posted at the lake when we checked. Keep kids and dogs out of the water.
  • Fish advisory. The state's Office of Environmental Health Hazard Assessment has a safe-eating advisory for Lake Chabot because of mercury levels in fish.
  • Boats and mussels. Boaters pay a $5 invasive mussel inspection fee at the Lake Chabot Marina & Cafe. Golden mussels have been found at Contra Loma and Lake Del Valle, so boats launched there face a 30-day quarantine from other district waters.

Hours, parking and tours

The park is open 5 a.m. to 10 p.m. unless posted otherwise. Gate hours change with the seasons: 6 a.m. to 7 p.m. in October and 6 a.m. to 6 p.m. in November and December. Parking is $5 per vehicle. Lake tours cost $10 an hour per adult and $6 an hour for kids 12 and under, and guided kayak tours are $45 per adult and $25 per youth for 2.5 hours.

The main entrance is at 17600 Lake Chabot Road in Castro Valley. From I-580 in San Leandro, take the Fairmont Drive exit and head uphill; the marina entrance is on the left at the bottom of the hill.