• 4,329 Geology and Geophysics Library (Leith)
• 139 Wisconsin's Water Library
• 19 Steenbock Library
• 2 Memorial Library
• 1 Limnology Library
• 1 Map Library (Robinson)
• 1 Middleton Shelving Facility
• 1 Verona Shelving Facility

• 30 Microforms
• 9 Maps, Atlases
• 2 Photos, Drawings, Prints
• 1 Computer file
• 1 Manuscripts, Theses

• 1,930 Groundwater
• 1,490 Water quality
• 1,029 Environmental aspects
• 779 Pollution
• 754 Groundwater flow
• 658 Hydrogeology
• 566 Water
• 558 Stream measurements
• 460 Aquifers
• 424 Quality
• 406 Mathematical models
• 379 Streamflow
• 364 Water-supply
• 324 Hydrology
• 266 Measurement
• 194 Floods
• 160 Water table
• 152 Nutrient pollution of water
• 146 Computer simulation
• 139 Flood forecasting
• 138 Runoff
• 130 Pesticides
• 122 Water resources development
• 119 Sediment transport
• 118 Suspended sediments

• 6,108 Geological Survey (U.S.)
• 364 National Water-Quality Assessment Program (U.S.)
• 182 United States. Environmental Protection Agency
• 164 United States. Department of Energy
• 146 United States. Bureau of Reclamation
• 122 United States. Bureau of Land Management
• 105 United States. National Park Service
• 82 United States. Army. Corps of Engineers
• 72 Washington (State). Department of Ecology
• 68 Southwest Florida Water Management District (Fla.)
• 57 South Florida Water Management District (Fla.)
• 55 New Jersey. Department of Environmental Protection
• 54 United States. Department of Energy. Nevada Operations Office
• 51 United States. Federal Highway Administration
• 50 U.S. Fish and Wildlife Service
• 47 Arkansas Soil and Water Conservation Commission
• 44 United States. Bureau of Indian Affairs
• 41 Minnesota. Department of Natural Resources
• 40 Florida. Department of Environmental Regulation
• 37 Puerto Rico Aqueduct and Sewer Authority
• 35 United States. Forest Service
• 34 Nassau County (N.Y.). Department of Public Works
• 33 California. Department of Water Resources
• 33 Kansas. Department of Health and Environment
• 33 St. Johns River Water Management District (Fla.)

• 6,221 English
• 2 Spanish

• 349 Florida
• 321 California
• 318 United States
• 255 Colorado
• 214 Washington (State)
• 199 New York (State)
• 174 Nevada
• 168 Texas
• 163 Pennsylvania
• 154 Minnesota
• 149 New Jersey
• 140 Kansas
• 138 New Mexico
• 138 Wisconsin
• 137 Ohio
• 136 Tennessee
• 133 Idaho
• 121 Arizona
• 115 Massachusetts
• 115 Oregon
• 108 Montana
• 101 South Carolina
• 100 Wyoming
• 99 Puerto Rico
• 97 North Carolina

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