Lower Crystal Springs Reservoir reservoir
Lower Crystal Springs Reservoir
Lower Crystal Springs Reservoir is a man-made reservoir located on the northern end of the Santa Clara Valley in California. The reservoir was built in 1888 to provide drinking water to the residents of San Francisco. The hydrology of the reservoir is primarily controlled by the San Andreas Fault, which runs directly under the reservoir. The reservoir is fed by surface flows from the San Mateo Creek and is also a snowpack provider during the winter months. The water from the reservoir is used for municipal purposes and agricultural irrigation. Recreational uses of the reservoir include fishing, boating, and hiking. The reservoir is home to a variety of fish species, including bass, catfish, and bluegill.
Daily levels at Lower Crystal Springs Reservoir
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
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 Lower Crystal Springs Reservoir -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| San Mateo C Bl Lo Crystal Sp Res Nr San Mateo Ca | 3 cfs | → |
| Pilarcitos C Bl Stone Dam Nr Hillsborough Ca | 2 cfs | → |
| Pilarcitos C A Half Moon Bay Ca | 5 cfs | → |
| San Francisquito C A Stanford University Ca | 1 cfs | → |
| San Gregorio C A San Gregorio Ca | 5 cfs | → |
| Matadero C A Palo Alto Ca | 0 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Lower Crystal Springs 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 Lower Crystal Springs Reservoir
Where does the data for Lower Crystal Springs 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.