7636

• UCREFRP Catalog Number: 7636
• Author: National Research Council
• Title: Editor
• USFW Year: Series
• USFW - Doc Type: 1992
• Copyright Material: YES

24 RESTORATION OF AQUATIC ECOSYSTEMS
TABLE 1.1 U.S. Water Budget for 1980 (billion gallons per day)

Regiona Supplyb Ground
Water
Depletion
Consumptive
Use
Reservoir
Evaporation

Yield`
1 77.3 0 0.4 0.2 76.7
2 96.5 0 1.7 0.2 94.6
3 212.6 0 5.1 0.5 207
4 76.8 0 1.3 0.3 75.2
5 140.1 0 1.7 0.4 138
6 43.3 0 0.4 0 42.9
7 79.7 0 1.5 0.6 77.6
8 75.4 0.04 7.14 0.30 68
9 7.7 0 0.1 0.4 7.2
10 67.3 2.2 16 3.3 50.2
11 63.7 3.6 9.6 1.4 56.3
12 35.9 3.1 6.5 1.8 30.7
13 5 0 2.4 0.8 1.8
14 12.3 0 2.3 1.7 8.3
15 -1.1 2.1 4.9 1.9 -5.8
16 17.1 12 3.9 0.2 25
17 290.6 0 12 0.6 278
18 86.9 1.4 25 0.5 62.8
19 921.04 0 0.04 0 921
20 14.3 0 0.7 0 13.6
To tal 2,322.54 24.44 103 15.1 2,229.1
°Regions relate to the hydrologic units assigned by the U.S. Geological S urvey (see
Figure 1.2).
bSurface runoff before adding ground water and subtracting consumptive use and
evaporation.
Surface water discharge from the region.
SouacE: Solley et al ., 1988.
ous ways. They stabilize lakes at levels that afford reliable access for
recreational boating, and they maintain navigational conditions for
commercial barges and ships. Manipulation of water levels offers
optimal flood protection and water supply for drinking and irriga-
tion. However, the controls also may have detrimental effects on
wildlife and other functions of aquatic ecosystems, and wetlands in
the littoral zone suffer from either too much or too little water. Dy-
namic hydrologic cycles are all but eliminated, causing the degrada-
tion of plant and animal communities.
Of the 2,200 billion gallons of water available per day in the United
States, approximately 4.7 percent is consumed (Table 1.1 and Figure
1.2). This total assumes, however, that the availability of water is