Modesto Reservoir Reservoir
Modesto Reservoir
Modesto Reservoir, located in Stanislaus County, California, was built in 1975 by the United States Bureau of Reclamation. The reservoir has a capacity of 29,000 acre-feet, and is fed by the Tuolumne River. The hydrology of the reservoir is managed by the Modesto Irrigation District, which uses the water for agricultural purposes. The surface flow provider for the reservoir is the Tuolumne River, and the snowpack provider is the Sierra Nevada Mountains. The reservoir is used for recreational purposes, such as camping, fishing, and boating. The reservoir also serves as a source of drinking water for the city of Modesto.
Daily levels at Modesto Reservoir
Storage volume, pool elevation, and total release plotted from the operating agency's daily observations.
Pool Elevation
ft · code 1
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 Modesto Reservoir -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Modesto Cn Nr La Grange Ca | 1,400 cfs | → |
| Tuolumne R Bl Lagrange Dam Nr Lagrange Ca | 189 cfs | → |
| Turlock Cn Nr La Grange Ca | 1,760 cfs | → |
| Tuolumne R A Modesto Ca | 181 cfs | → |
| Black C Nr Copperopolis Ca | · | → |
| San Joaquin R Nr Crows Landing Ca | 264 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Modesto Reservoir.
Boat launches
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Campgrounds
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Fishing spots
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River runs
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About Modesto Reservoir
Where does the data for Modesto Reservoir 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.