Trinity Lake
As of September 12, 2026, Trinity Lake is holding 925 acre-ft of water — 1% of normal storage for this date. Storage data refreshed throughout the day.
Trinity Lake
Trinity Lake is a reservoir located in Trinity County, California, formed by the Trinity Dam on the Trinity River. The lake was created in 1961 as part of the Central Valley Project, a federal water management project. The lake's hydrology is regulated by the dam and the Trinity River, which provides the lake with water from snowpack and rainfall in the surrounding mountains. The lake serves as a source of irrigation water for agriculture in the surrounding areas, as well as a popular destination for recreational activities such as fishing, boating, and camping. The lake's surface flow is also important for downstream water users, including several Native American tribes that rely on the Trinity River for their livelihoods. Despite concerns over drought and water management in California, the lake remains an important resource for the region.
Daily levels at Trinity Lake
Storage volume, pool elevation, and total release plotted from the operating agency's daily observations.
Storage
acre-ft · code 2
Pool Elevation
ft · code 1
Inside the reservoir
The real shoreline of this water body, with a depth model scaled so the basin holds exactly its recorded storage. Drag to orbit, scroll to zoom, and use the slider to drain and refill it. Click anywhere on the basin for the modelled depth there.
How this is built. The shoreline is the National Hydrography
Dataset polygon for this water body (“Trinity Lake”),
matched to the dam by proximity and confirmed by comparing its area with the
National Inventory of Dams surface area.
Depth is modelled, not surveyed: the basin is shaped by distance from
shore — deep in open water, shallow in the bays — and scaled so its
volume equals the recorded storage. No national bathymetric survey exists for
US reservoirs. Treat the shoreline, area and volume as measured, and the depth
distribution as an informed approximation.
Above normal pool, water is shown rising within the normal-pool
shoreline. Where it would actually spread depends on the surrounding
terrain, which is not modelled here — a reservoir in a steep canyon barely
widens, one on flat ground can spread a long way. This is a depth and volume
figure, not an inundation map. Official inundation mapping for a dam
comes from its Emergency Action Plan.
Plan around the weather
Same NOAA / yr.no feed Snoflo's iOS app uses. Watch the precipitation column on the meteogram -- rain on the basin upstream typically lifts inflow 24-72 hours later.
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
5-day forecast table
Every 3 hours, broken out across temperature, snow, rain, humidity, and wind. Each cell is colour-coded relative to the column min/max.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day temperature & precipitation
Daily temperatures, snow, and rain projected over the next two weeks.
Nearby streamflow gauges
USGS streamgauges around Trinity Lake -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Trinity R A Lewiston Ca | 1,200 cfs | → |
| Rush C Nr Lewiston Ca | 1 cfs | → |
| Grass Valley C Nr Lewiston Ca | 18 cfs | → |
| Trinity R Bl Limekiln Gulch Nr Douglas City Ca | 1,180 cfs | → |
| Indian C Nr Douglas City Ca | 4 cfs | → |
| Trinity R A Douglas City Ca | 1,170 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Trinity Lake.
Boat launches
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Campgrounds
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Fishing spots
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River runs
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About Trinity Lake
What is the water level at Trinity Lake right now?
As of September 12, 2026, Trinity Lake is holding 925 acre-ft, about 1% of normal for this date. Pool elevation and the year-over-year trend are shown above.
Is Trinity Lake high or low right now?
Compare the percent-of-normal figure on this page: above 100% means storage is higher than the historical average for the date (a wet year), below 100% means lower (a dry year or drought). The daily-levels chart shows the current trend.
Where does the data for Trinity Lake come from?
Daily storage, pool elevation, and release rates are sourced from USGS, USBR, and USACE monitoring stations. Weather forecast comes from NOAA / yr.no -- the same feed Snoflo's iOS app uses.
How often is the report updated?
Storage observations are updated daily by the operating agency. The 15-day weather forecast refreshes throughout the day. Snoflo caches and renders the most recent observation -- check the "as of" timestamp on the storage card.
What does the Hazard hazard rating mean?
The Corps of Engineers' hazard potential classification grades probable consequences if the dam fails: High = probable loss of human life; Significant = no probable loss of human life but possible economic loss / environmental damage; Low = no probable loss of human life, only minor economic / environmental losses. See the Dam Data Reference card below for the full definitions.
What's "% of normal"?
The current storage value compared to the historical average storage on this calendar day. 100% = right on average; values above 100% mean above-normal storage (wet year); values below mean below-normal (dry year or drought).
Can I get alerts when storage crosses a threshold?
Yes -- alerts are managed in the Snoflo iOS app. Favorite this reservoir, set a threshold, and you'll get a push the moment conditions cross.
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