Tulloch Reservoir water level
▼ 5.5 points from 93.6% a year ago
Source: waterdata.usgs.gov/monitoring-location/USGS-11299995, accessed October 1, 2026. Updated every 6 hours.
Tulloch Reservoir is at 89.6% of full pool (508.29 ft) as of September 29, 2026. Tulloch Reservoir was last full on September 21, 2026 (95.4% of normal storage). Tulloch Reservoir is near Knights Ferry, California. It has boat launch and marina, managed by Tri-Dam Project (Oakdale Irrigation District / South San Joaquin Irrigation District). Check current swimming advisories at Tri-Dam Project reservoir recreation notes before you go.
Tulloch Reservoir level history
This site counts a reservoir as full on a day its storage is at or above 95% of the dam's normal storage (National Inventory of Dams). Many reservoirs rarely reach 100%, even in wet years, because operators release water for irrigation, power or flood control before they fill, so this site treats 95% as full. Highs and lows are daily readings in the published data, not official records. Source: USGS daily data.
Storage, % of full pool, since 1957
Tulloch Reservoir is falling: 90.6% full, down 2.2 percentage points since September 27, 2026.
On this same date last year (September 28, 2025), Tulloch Reservoir was 93.6% full, 3 percentage points higher than today's 90.6%.
Weekly averages of the source's daily readings; older years may be monthly or sparser where that is all the source published. Download the charted data (JSON).
Tulloch Reservoir map
Tulloch Reservoir is at 37.8760, -120.6044. Open in OpenStreetMap.
The dam
- Flood control
- Hydropower
- Recreation
Sources: nid.sec.usace.army.mil, accessed September 29, 2026
Visiting Tulloch Reservoir
- Boat launch
- Marina
Good to know:
- Shoreline is mostly private with substantial residential development on the Calaveras County side. Public access is via privately owned docks and fee-based private facilities.
- South Shore access via Tulloch Dam Road off Highway 108; North Shore via O'Byrne's Ferry Road off Highway 108.
- Specific day-use and launch fees are set by private marina operators, not published as a single Tri-Dam fee schedule - confirm with the facility you plan to use.
Swimming
Water-quality and swimming advisories change without notice. Always check Tri-Dam Project reservoir recreation notes before you go.
Sources: tridamproject.com/reservoirs, accessed September 28, 2026
On the water
No campgrounds, boat ramps, or swim spots linked to Tulloch Reservoir yet.
Common questions
- Tulloch Reservoir is at 89.6% of full pool (508.29 ft) as of September 29, 2026.
- Tulloch Reservoir was last full on September 21, 2026, when it held 95.4% of its normal storage. This site counts a reservoir as full on a day its storage is at or above 95% of the dam's normal storage (National Inventory of Dams). Many reservoirs rarely reach 100%, even in wet years, because operators release water for irrigation, power or flood control before they fill, so this site treats 95% as full. Based on USGS daily data since November 25, 1957.
- In USGS daily data since November 25, 1957, Tulloch Reservoir's highest storage was 103.4% of normal storage on January 6, 1965. Its lowest after it first filled (June 9, 1958) was 6.8% of normal storage on October 3, 1960. These are the highest and lowest daily readings in the published data, not official records.
- Tulloch Reservoir is near Knights Ferry, California (37.8760, -120.6044).
- Utility operates the dam at Tulloch Reservoir.
- Tulloch Reservoir's dam is used for Flood control, Hydropower, Recreation.
- Tulloch Reservoir has no designated swim area on record. Check current advisories at Tri-Dam Project reservoir recreation notes before you go.