Where America’s water goes

Every moving streak of light is water. It leaves a river, a lake, an aquifer or the sea and travels to the place where it was used, taking the color of that use: orange for power plants, green for crops, gold for public water systems, and so on. The more water, the more light.

Some of that water is consumed, which means it evaporates, goes into crops or products, or otherwise leaves the local water system. It rises as white mist. The rest goes back to rivers and aquifers after it is used, and the map draws that return in blue. The U.S. Geological Survey estimated consumption only for crops, golf courses and power plants in 2015, so for the other uses the light stops where the water arrives.

Pick a use in the panel on the left to see only its water, with the counties shaded by how much of it they withdrew per square mile and the places that withdrew the most labeled. Click any county to name where its water comes from and where it goes. Click a power plant, a dam or a marked facility for its own numbers. Underground shows the aquifers as solid bodies under a glass surface, with wells lifting water out of them.

Drag to move, scroll or pinch to zoom, and right-drag (or twist two fingers) to turn and tilt. With the map selected, the arrow keys move it, N switches between day and night, U goes underground, and Escape steps back.

Water use

The U.S. Geological Survey’s estimate of withdrawals for every county in 2015 (Dieter and others, 2018, county data version 2.0), in nine uses and four kinds of source: fresh and saline, surface and ground water. It is the source of every volume on the map and of the national total. USGS split irrigation into crops and golf courses in 36 states and the District of Columbia. In the other states golf is counted inside crop irrigation.

Consumption

Shown only for crops, golf courses and thermoelectric power, the uses for which USGS estimated consumption in 2015. For the other uses the map shows water arriving and stops there, which does not mean none of it was consumed.

Power plants

The 1,122 plants in the USGS model of thermoelectric water use for 2015 (Harris and Diehl, 2019, data version 1.2). Each county’s thermoelectric estimate is split among its plants in proportion to that model, and each plant’s own model estimate is shown beside it.

Aquifers and groundwater

Withdrawals by aquifer are from Lovelace and others (2020), estimated groundwater withdrawals from principal aquifers in 2015, county-level data (USGS). The outlines are the USGS map of principal aquifers, which shows the uppermost principal aquifer at each place, so deeper ones (such as the Floridan aquifer beneath Florida’s surficial aquifer) are hidden. Their outlines come from that map, but every body is drawn at the same depth and thickness, so the depths on the map mean nothing. About 14 billion gallons a day was pumped from glacial, alluvial and other aquifers the map does not outline. Depletion from 1900 to 2008 is from Konikow (2013), and the High Plains aquifer’s water in storage from McGuire (2017).

Data centers

For scale only, and not part of the 2015 totals. Lawrence Berkeley National Laboratory’s 2024 report estimates U.S. data centers consumed about 66 billion liters (17.4 billion gallons) of water on site in 2023, and about 800 billion liters more were consumed generating their electricity. Their water is counted inside public supply and industry in the USGS figures, so the map draws no flows for them. The locations are data centers mapped in OpenStreetMap, which misses many.

Rivers, lakes and canals

Rivers are HydroRIVERS version 1.0 (Lehner and Grill, 2013), with each reach’s modeled long-term natural discharge for 1971 to 2000, which leaves out withdrawals and dams. Lakes and reservoirs are Natural Earth. Aqueducts and canals are mapped from OpenStreetMap; where a flow is given it comes from the operator’s or the Bureau of Reclamation’s report for that year, and it is the water entering the system, so less reaches the far end.

Dams and facilities

Every record in the U.S. Army Corps of Engineers’ National Inventory of Dams, sized by storage. Water towers, treatment plants, wastewater plants, golf courses and data centers are from OpenStreetMap (© OpenStreetMap contributors, ODbL), which is thorough in some places and patchy in others.

Land and terrain

Land cover is the National Land Cover Database (MRLC): 2021 for the lower 48, 2016 for Alaska and 2001 for Hawaii and Puerto Rico. The city lights at night are painted from its developed land classes. Terrain is NOAA’s ETOPO 2022 at 15 arc-seconds, exaggerated vertically: 24 times for the whole country and about 2 times up close. Up close, fields, center pivots and city blocks are painted patterns placed by the land cover and each county’s irrigated acreage, so individual fields are not real ones.

Where the flows start and end

Inside a county the map places surface intakes on its largest rivers or lakeshores, wells beneath the land they serve, irrigation on cropland, golf on mapped golf courses, utilities through a mapped treatment plant into developed land, and power plants at their reported coordinates. The volumes are the estimates. The paths are drawn to show them.

Sources: USGS county water use, 2015 · Dieter and others (2018) · Harris and Diehl (2019) · Lovelace and others (2020) · Konikow (2013) · McGuire (2017) · LBNL (2024) · HydroRIVERS · National Inventory of Dams · NLCD · ETOPO 2022 · OpenStreetMap · Reclamation, Colorado River 2015 · Natural Earth

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