S14 The West's water savings account
Twenty teacups,
one balance sheet.
Twenty Western reservoirs drawn as the U.S. Bureau of Reclamation has always drawn them. Each teacup carries one number that decides whether forty million people in Phoenix, Las Vegas, Los Angeles, and the Central Valley wake up to water the next morning.
Scroll through three views built from public USBR and USGS data. The teacup grid is the savings statement. The elevation cliff is the warning siren on Lake Mead and Lake Powell. The snow-to-storage scatter is the leading indicator that warming is breaking.
§ I The bank statement the West avoids reading
The U.S. Bureau of Reclamation has drawn its reservoir reports the same way for fifty years. A teacup, filled to the current level, with a thin line showing the historical average.
It is the most honest financial chart in American government. Each cup is a balance. The line is the average from three decades of records. Below the line, the West is overdrawn. Far below it, the dam itself starts to ration.
In June 2022, Lake Mead fell to 1,040 feet. That was 145 feet above dead pool, the level where Hoover Dam can no longer release water through its lowest outlet. Las Vegas, Phoenix, Los Angeles, and a quarter of California's farmland all sit downstream. Wet winters in 2023 and 2024 bought a partial reprieve. The structural deficit, the gap between what the Colorado promises and what it delivers, is still there.
This page draws twenty of the West's biggest cups together. It is not a forecast. It is a balance sheet for water, refreshed once and frozen, the way a printed annual report freezes a moment in finance.
S14.1 The teacup grid
Each cup is one reservoir. Fill height shows current storage as a percentage of total authorized capacity. The dashed line marks the historical average for this time of year. Filter by basin or by status. Click any cup to pin its details below.
What this means
Forty percent full is not always a crisis. Lake Mead at thirty-five percent is. The line in each cup says why. It is what the reservoir should have held on this day, averaged across three decades. The cups below the line are the ones running an overdraft. The deeper the deficit, the more the basin is relying on snowpack that has not yet arrived, or on groundwater that no longer fills back up between droughts.
The Colorado River basin remains the visible crisis. California recovered hard in 2023 and 2024 after twelve months of record snow. The Pacific Northwest sits close to average most years. The Rio Grande is the quiet emergency that nobody west of Albuquerque tracks daily.
S14.2 The elevation cliff
Mead and Powell only. The y-axis is feet above sea level, the units the dam operators actually plan in. The horizontal bands are the policy triggers, the levels where the Colorado River Compact, the 2007 Interim Guidelines, and the 2019 Drought Contingency Plan force cuts on the seven basin states. The dotted floor is dead pool, the elevation at which the dam can no longer release water through its outlet works.
What this means
Mead and Powell are the two largest reservoirs in the United States. Together they hold more than fifty million acre-feet at full pool and serve roughly forty million people downstream. The cliff is the same shape on both. Both fell roughly a hundred and forty feet between 2000 and 2022. Both rebounded twenty to forty feet on the 2023 atmospheric river winter. Both are still well below the upper policy line that the seven basin states wrote in 2007 to define normal.
Read the floor. Dead pool on Mead is 895 feet. Dead pool on Powell is 3,370 feet. The buffer between today's elevation and the floor is what the operators have to negotiate with for the next decade.
S14.3 Snow to storage, by basin
The West does not get rain when it needs it. It gets snow, in winter, and the reservoirs catch the melt. April 1 snow water equivalent, the height of liquid water locked inside the snowpack, is the closest thing the system has to a leading indicator. Each dot is a basin-year pairing April 1 SWE against the same basin's storage at the end of the water year.
What this means
Two trends sit on this chart. The line from the lower left to the upper right is the old relationship between snow and storage. More snow in April meant more water in October. The cloud of points has been sliding downward since 2000, especially in the Colorado basin. The same snowpack now produces less storage, because warmer ground absorbs more meltwater, more of the precipitation falls as rain in winter and runs off before it can be captured, and atmospheric evaporative demand has risen.
The slope is not gone. It is flatter. That is what aridification looks like on a chart: the relationship between input and output gets noisier and weaker, year by year.
§ V Receipts
§ VI Methodology & Colophon
Every chart is hand-drawn in SVG by a small vanilla JavaScript module. No frameworks, no build step, no analytics trackers. The data is baked into the page as static JSON. The teacup shape is parametric, redrawn for each reservoir at load time.
Reservoir levels and capacities come from the U.S. Bureau of Reclamation RISE platform, the USGS National Water Information System, and the California Department of Water Resources Data Exchange Center. Snowpack figures come from the NRCS SNOTEL network. Historical-average curves are computed against the 1991 to 2020 period where available. The snapshot reflects April and May 2025 conditions, not live data.
USBR RISE · Reclamation data platform ↗
USGS NWIS · water services API ↗
California DWR · Data Exchange Center ↗
NRCS SNOTEL · snow water equivalent network ↗
USBR · Lake Mead elevation chart ↗
The page is a snapshot, not a live feed. Daily refresh from USBR RISE and USGS is straightforward and is the intended next step. The historical-average curves shown on each teacup are a simplification of more detailed daily exceedance percentiles that Reclamation publishes. Groundwater and tributary contributions are not visualized; the Central Valley and Ogallala aquifer drawdown is a hidden counterweight that surface storage alone cannot tell you about.