Grass Valley Creek Near Lewiston flow report
As of July 14, 2026, Grass Valley Creek Near Lewiston is flowing at 18 cfs, rising 18% over the past 24 hours. Source: USGS gauge #11525630, refreshed throughout the day.
Historical Data
Grass Valley Creek Near Lewiston at a glance
How Grass Valley Creek Near Lewiston is running right now, where it sits on the map, and the key gauge stats.
Grass Valley Creek Near Lewiston is flowing at 18 cfs, with the water sitting 3.75 ft at the gage. Flow is up 18% since yesterday — a rising hydrograph.
This is USGS gauge #11525630 in California. Over the past 10 days the average has been 15 cfs, peaking at 18 cfs.
For real-time updates and historical context, see the realtime view or the historical comparison. Browse other gauges in the California flow report.
How does this compare to past years?
Year-over-year overlay, annual peak discharge, the full distribution of daily flows on record, and the gauge's rating curve.
Weather Forecast
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.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day forecast
Daily temperatures, snow, and rain projected over the next two weeks.
Grass Valley Creek Near Lewiston
The river is a vital water source for agricultural irrigation, hydropower, and fish habitat, making it important for farmers, energy providers, and conservation groups. The gauge also monitors the effects of seasonal trends, such as snowmelt and rainfall, on river flow. There are several dams and tributaries that contribute to the stream flow, including the Trinity Dam, which produces hydropower for California residents. Additionally, the river is known for its recreational opportunities, such as fishing and rafting. Overall, the stream gauge provides valuable data for stakeholders in the Trinity River watershed.
Nearby streamflow levels
Cross-check Grass Valley Creek Near Lewiston's discharge against nearby gauges to spot whether the change here is local or regional.
| Gauge | Streamflow |
|---|---|
| Grass Valley C Nr Lewiston Ca | 18 cfs |
| Rush C Nr Lewiston Ca | 2 cfs |
| Trinity R Bl Limekiln Gulch Nr Douglas City Ca | 464 cfs |
| Indian C Nr Douglas City Ca | 6 cfs |
| Trinity R A Lewiston Ca | 450 cfs |
| Trinity R A Douglas City Ca | 502 cfs |
Nearby snowpack data
Snowpack at SNOTEL stations near Grass Valley Creek Near Lewiston. Spring snowmelt is the dominant driver of streamflow in mountain basins -- a deep snowpack upstream means more runoff later in the season.
| SNOTEL station | Snowpack |
|---|---|
| Nohrsc Red Rock Mountain | — |
| Big Flat | 0 in |
| Bonanza King | — |
| Nohrsc Slate Creek | 1 in |
| Highlands Lakes | 19 in |
| Mission Ridge Snow Pillow | — |
River levels & flood safety
- Read the level before you go
- A river that's runnable at one flow can be deadly at another. Check current discharge and gage height — like the values shown above — against the flood-stage thresholds, and remember levels can spike fast after rain or a dam release.
- Respect cold water
- Snowmelt rivers run cold even in summer. Sudden immersion triggers cold-water shock and saps strength within minutes. Wear a PFD, dress for the water temperature (not the air), and never wade or paddle alone.
- Watch for swiftwater hazards
- Strainers (downed trees), undercut rocks, and low-head dams are the deadliest features on moving water. High, fast, muddy water hides them. If in doubt, scout from shore and portage.
- Mind flash floods & releases
- Narrow canyons can flood from a storm miles upstream, and dam-controlled reaches can rise without warning. Know the forecast, the release schedule, and your exit before you launch.
Track Grass Valley Creek Near Lewiston in the Snoflo app
Save this gauge as a favorite, set push alerts when streamflow crosses a threshold (e.g. "alert me when Grass Valley Creek Near Lewiston crosses 5,000 cfs"), and Snoflo's iOS app will push the moment USGS reports the crossing.
About Grass Valley Creek Near Lewiston
Where does the streamflow data for Grass Valley Creek Near Lewiston come from?
Discharge, gage height, and water temperature come directly from the USGS streamflow gauge 11525630. Snoflo refreshes the time series throughout the day. Forecasts come from the NOAA / yr.no feed Snoflo's iOS app uses.
How often is the report updated?
USGS gauges report continuously (typically every 15 minutes). Snoflo pulls fresh values throughout the day — look for the "as of" timestamp on the streamflow hero card.
What's the difference between discharge and gage height?
Discharge (cubic feet per second, or cfs) is the volume of water flowing past the gauge each second. Gage height is how high the water sits at the gauge (feet). They're related by a rating curve specific to each gauge — higher water means more flow, but the exact ratio depends on channel shape.
How is "percent of median" calculated?
Today's discharge is compared to the historical median discharge on this calendar day across the gauge's full record. 100% = right on median; 200% = a very high year; 30% = a drought-level low.
What are flood stages, and is this river safe right now?
Flood stages are NWS-defined gage-height thresholds — Action, Minor, Moderate, Major — marking when nearby roads or floodplains start to be affected. "Safe" depends on your activity and skill: a level that's a fun paddle for an expert can be lethal for a wader. Always check the current level against the thresholds above and the safety links, and when in doubt, stay off the water.
Can I get alerts when Grass Valley Creek Near Lewiston rises?
Yes — flow alerts are managed in the Snoflo iOS app. Favorite this gauge, set a streamflow threshold (e.g. "alert me when discharge crosses 5,000 cfs"), and you'll get a push the moment USGS reports the crossing.
Access the free Grass Valley Creek Near Lewiston report
Create your free account to track this river — and everything else you love on the water.
- Flow alerts — get pinged the moment this river hits your range
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- Full history & forecasts — plus the free iPhone app