The USGS Water Science School
Water Science water-use pages
Categories of Use:
Source and Use of Freshwater in the United States
This diagram uses a "cylinder and pipe" layout to show the source (surface water or groundwater) of the Nation's freshwater and for what purposes the water was used in 2005. The data are broken out for each category of use by surface water and groundwater as the source.
Data are rounded and are reported in million gallons per day (Mgal/d) .
The top row of cylinders represents where America's freshwater came from (source) in 2010, either from surface water (blue) or from groundwater (brown). You can see most of the water we use came from surface-water sources, such as rivers and lakes. About 25 percent of water used came from groundwater. The pipes leading out of the surface-water and groundwater cylinders on the top row and flowing into the bottom rows of cylinders (green) show the categories of water use where the water was sent after being withdrawn from a river, lake, reservoir, or well.
For example, the blue pipe coming out of the surface-water cylinder and entering the public supply cylinder shows that 26,300 Mgal/d of water was withdrawn from surface-water sources for public-supply uses (you probably get your water this way). Likewise, the brown pipe shows that public-suppliers withdrew another 15,700 Mgal/d of water from groundwater sources.
Each green cylinder represents a category of water use. The industrial cylinder, for instance, shows how much water the United States used, each day, by industries. In 2010, about 15,000 Mgal/d of water was used for industrial purposes, with about 12,100 Mgal/d coming from surface water and about 2,900 Mgal/d coming from groundwater.
You can see that although the Nation uses much more surface water than groundwater, groundwater has significant importance for some of the categories. Almost all self-supplied domestic water came from groundwater; over 40 percent of irrigation water was groundwater; and more groundwater than surface water was used for livestock purposes.