Blue Mesa and Lake Havasu

Thousands of acre feet.

Here is the link to my original interactive visualization that is updated daily

After making my California Reservoirs dashboard marimekko graph, I decided to make a similar Colorado river reservoir page. The Lower Colorado water is used in Southern California and Arizona.

The area of each rectangle shows the total volume of the reservoir in thousands of acre feet (kaf). The blue section shows how much of the capacity is full. You can see the two main reservoirs, Lake Mead and Lake Powell are not in good shape relative to their normal historical levels.

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Data Sources and ToolsThe data on water storage comes from the US Bureau of Reclamation's Lower Colorado River Water Operations website. Historical reservoir levels comes from the water-data.com website. Python is used to extract the data and wrangle the data in to a clean format, using the Pandas data analysis library. Visualization was done in javascript and specifically the D3.js visualization library.

that makes sense, I misunderstood you earlier comment.

You are correct that not all snowpack melt water can flow through a reservoir. I guess perhaps my wording is confusing. The snowpack is like another reservoir in that it stores water, but it's not exactly like a reservoir, in that all of that water will be captured.

The problem is the snow sensor data isn't available before the 70's and 80's.

California’s snow pack is essentially another “reservoir” that is able to store water in the Sierra Nevada mountains. Graphing these things together can give a better picture of the state of California’s water and the current conditions of drought. The recent atmospheric rivers have increased storage in reservoirs and snow in California immensely.

Click here to view interactive version that is updated daily.

Converting snowpack water content (measured in inches of water at 120 different snow sensor sites in the Sierras) into a total volume of water was done by correlating snow sensor data with an estimated the volume of the Sierra snow from 2016 journal article (Margulis et al). See link for more info.

Sources and Tools

Snow and reservoir data is downloaded from the California Data Exchange Center website of the California Department of Water Resources using a python script. The data is processed in javascript and visualized here using HTML, CSS and javascript and the open source Plotly javascript graphing library.

You are welcome. Glad you will find it useful. You can check out the rainfall and reservoir visualizations I've made as well.

These two reservoirs are on the Colorado river so I don't think California's snow has any impact.

We are having epic rain in California and that means epic snowfall in the Sierra Nevada Mountains. I wanted to make an interactive and current snowfall visualization to keep track of the amount of water being stored in the mountains. This is an average of snow water content for all of the 120 snow sensor locations in the Sierra. You can also look at specific regions (Northern, Central and Southern Sierras).

The blue/black lines on the graph (from top to bottom) represent the 100th(max), 90th, 75th, 50th (median), 25th, 10th and 0th (min) percentiles of snow water content for each date from 1970 to 2022. The red line is the current water years value.

In general, the snowpack water content to snow depth is about a 3 to 1 ratio so in the image, the average of 22" of snow water content amounts to about 66" (5ft 6inches or ~1.67 meters). It is much more (maybe 10 to 1) when the snow first falls, but over time it settles and also compacts from the overlying snow to get to this lower number.

Here is the interactive and updated daily (sometime in the west coast morning 8-10am) visualization.

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Sources and ToolsData is downloaded from the California Data Exchange Center website of the California Department of Water Resources using a python script. The data is processed in javascript and visualized here using HTML, CSS and javascript and the open source Plotly javascript graphing library.

if you want something machine readable (csv or json) you can choose that here:

https://cdec.water.ca.gov/dynamicapp/wsSensorData

In case you still need it, here's Hetch Hetchy storage data

https://cdec.water.ca.gov/dynamicapp/QueryDaily?s=HTH&end=2023-01-05

yeah, I tried something like that, but there are 48 reservoirs represented on the graph and so you aren't going to be able to read all of them regardless. I did add the ability to select which reservoirs to show on the graph (in the interactive version) which can let you visualize the smaller reservoirs.

But the overall goal was to show the amount of water in reservoirs so it's not that helpful if a tiny reservoir (amounting to less than 1% of state storage capacity) is full

it's going up, but not that fast. In the last 10 days or so, Shasta, the biggest reservoir, has gone up from 1.44 million acre feet to 1.58 million acre feet. This increase is 3% of the total reservoir storage capacity.

thanks! glad you are finding it interesting.

It's ridiculously rainy here in California but reservoir levels in the state are still not to historical levels because of the prolonged drought we've been in.

Here's the interactive version, which is updated hourly

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Data and Tools
The data on water storage comes from the California Department of Water Resources’ (DWR) Data Exchange Center. Python is used to extract the data from this page hourly and wrangle the data in to a clean format. Visualization was done in javascript, HTML and CSS and specifically the D3.js visualization library.