Water and hydrology resources on the internet: Reservoir conditions, precipitation indexes, snow charts, drought maps and more …
Reservoir Conditions
Reservoir Conditions
Go here for an interactive map of the major reservoirs in the state. Note that it can take a few extra seconds to load, so be patient. Click on a reservoir name to see storage graphs for individual reservoirs. (Note: for a printable version of this graphic, click here.)
Reservoir Conditions – Top of Conservation Conditions (Statewide)
Although it’s not an issue this year with the reservoirs drawn down low, this special variation of the standard DWR reservoir webpage shows the amount of storage available for flood control. Note that this page can be slow to load.
Reservoirs – Drought Status Percentiles
This graphic by the Department of Water Resources characterizes reservoirs by drought status. It is published monthly.
For even more on reservoir conditions …
- Click here for the California Data Exchange Center (CDEC) webpage for reservoirs.
- For more information on Central Valley reservoirs and operations, click here.
Precipitation Data and Indexes
Daily Hydrologic Update
Get an overview of precipitation data and reservoir levels on a statewide basis on this page from the Department of Water Resources.
Northern Sierra Precipitation: Eight Station Index
Click on the image to view a graph of the Northern Sierra 8-station index.
San Joaquin Precipitation: Five Station Index
Check out a graph of the San Joaquin 5-station index here.
Tulare Basin Precipitation: Six Station Index
Check out the newest index, the Tulare Basin Six Station index here.
For even more on precipitation …
Snow Data
Snow Water Content graph
View a snow water content graph for the water year for each of the three zones in the Sierras.
Snow Water Content map
Get a simple map of current snow water content levels of the three zones in the Sierras here.
Snow maps
You can find just about anything else you want to know about the snowpack – like temperature, snowmelt, sublimation and more – at the National Weather Service’s Snow Analysis page.
For even more on snow conditions:
- Click here for the California Data Exchange Center (CDEC) webpage for snow conditions.
- Click here for the snow analyses page at the National Weather Service.
Current weather and data
USGS California Water Data
Find real-time streamflow conditions, water quality data, and other current California conditions including surface-water, groundwater, spring sites, atmospheric sites and more at the USGS California Water Center.
California-Nevada River Forecast Center
River, snow, precipitation, temperature, freezing levels, water temperature and more is available at the National Weather Service’s California-Nevada River Forecast Center.
For more on weather conditions …
Climate and Drought
California Climate Data Archive
Get long term precipitation and temperature data and more at this climate montioring and data access website sponsored by the California Energy Commission, the Scripps Institute of Oceanography and the Western Regional Climate Center.
Drought Monitor
The U. S. Drought Monitor is published every Thursday. Click on the image to view the latest map.
GRACE Data
Click on the image to view groundwater and soil moisture conditions from GRACE data assimilation at the National Drought Mitigation Center website.
Vegetation Drought Response Index (Vegi-DRI)
Produced every two weeks, the maps provide regional to sub-county scale information about drought’s effects on vegetation, integrating satellite-based observations of vegetation conditions, climate data, and other biophysical information such as land cover/land use type, soil characteristics, and ecological setting.
