Key Measures at a Glance
Lake Chabot is a reservoir in Alameda County, California, operated by the East Bay Municipal Utility District (EBMUD). Below are verified attributes relevant to depth, capacity, and access. Exact figures can vary with rainfall, conservation measures, and operational drawdowns.
| Attribute | Verified Detail | Source Type |
|---|---|---|
| Maximum Official Depth | About 185 feet (56 meters) | EBMUD and public works records |
| Average Depth | Approximately 80 to 90 feet (24–27 meters) | Bathymetric surveys and EBMUD summaries |
| Water Surface Area | Roughly 315 acres (127 hectares) | EBMUD reservoir data |
| Total Capacity (Design) | About 220,000 acre-feet (~271,000,000 cubic meters) | EBMUD capacity tables |
| Watershed Area | Approximately 13,500 acres (5,463 hectares) | EBMUD watershed maps |
| Primary Purpose | Water storage and emergency supply; recreation secondary | EBMUD reservoir operations policy |
How Measurement Context Matters
Depth specifications for reservoirs are often stated as maximum depth, average depth, or operational ranges. Maximum depth is the deepest point measured from surface to bottom; average depth integrates volume and surface area. Capacity reflects stored water volume, which supports supply reliability. Because Lake Chabot serves EBMUD’s water system, actual depth and volume fluctuate with drought, conservation, and drawdown schedules.
Bathymetry and Survey Sources
Bathymetric mapping uses sonar and lidar to produce depth contours and volume calculations. EBMUD conducts periodic surveys to track sedimentation and structural integrity. These data underpin official metrics such as maximum depth, average depth, and total capacity. Independent public works reports and agency documentation corroborate these figures, though publicly available datasets may vary in resolution.
Practical Considerations for Visitors
- No public swimming: Lake Chabot is a drinking water reservoir, and swimming is prohibited to protect water quality and safety.
- Fishing allowed with license: Shore fishing and bank fishing are generally permitted; check current EBMUD fishing rules for species and gear restrictions.
- Boating restrictions: Only electric-powered boats are allowed; gasoline motors are not permitted to reduce pollution and disturbance.
- Shore access and trails: The lake is surrounded by parkland with walking and hiking trails; stay on designated paths and respect seasonal closures.
- Safety and emergencies: Depth changes can affect boating hazards; review posted signage and EBMUD safety notices at the reservoir entrance.
Comparison with Regional Reservoirs
Within the East Bay, reservoirs vary widely in size and depth. Lake Chabot’s maximum depth of about 185 feet is substantial but not extreme compared to others. Its design capacity supports water storage for drought and emergencies. Context matters: depth alone does not indicate water quality, recreational opportunity, or operational rules, which differ across sites.
| Reservoir (East Bay region) | Maximum Depth | Primary Use |
|---|---|---|
| Lake Chabot | ~185 ft (56 m) | Water storage, limited recreation |
| San Pablo Reservoir | Over 200 ft in places | Water supply |
| Briones Reservoir | Variable; generally less deep | Water storage |
Operational and Environmental Factors
Reservoir depth and volume are managed to balance supply, safety, and ecology. During drought, agencies may limit draws and maintain higher minimum depths for ecosystem stability. Sediment accumulation can reduce effective storage over decades, influencing usable depth and requiring dredging decisions. Spillway capacity and seismic considerations also affect how and when water levels are adjusted.
Data Sources and Verification Notes
Information in this profile draws from EBMUD reservoir data, regional water agency reports, and public works records. Depth and capacity figures are commonly cited in agency documents, National Weather Service river reports, and county planning materials. When precise real-time depth is not publicly published, maximum published figures represent standard references used by engineers and planners.
Frequently Asked Questions
- How deep is Lake Chabot at its deepest point? The maximum recorded depth is approximately 185 feet (56 meters).
- What is the average depth of the lake? The average depth is roughly 80–90 feet (24–27 meters).
- Can I swim in Lake Chabot? No, swimming is not permitted because it is a drinking water reservoir.
- What activities are allowed on the lake? Electric-boating and shore-based recreation such as hiking and fishing (with appropriate license) are generally allowed; check current rules at the site.
- How often are depth and capacity measured? Agencies conduct periodic bathymetric surveys and continual monitoring; exact intervals vary by management needs.
Summary and Takeaways
Lake Chabot’s maximum depth is approximately 185 feet, with an average depth near 80–90 feet, and a design capacity around 220,000 acre-feet. It is a reservoir dedicated primarily to water storage for the East Bay, operated by EBMUD. Recreational use is permitted under specific rules, including restrictions on swimming and boat motors. Depth and volume figures can vary with operational decisions, drought, and sedimentation. For current conditions, consult EBMUD notices and local park authorities before visiting.