Region
United States
7
Texas
5
Edwards Aquifer (Tex.)
4
Trinity Aquifer (Tex.)
4
Atlantic Coast (U.S.)
3
Comal County
3
Alaska
2
Bexar County
2
Massachusetts
2
South Carolina
2
Arkansas
1
Atlantic Ocean
1
Boston
1
Boston Harbor
1
Boston Harbor (Mass.)
1
California
1
Caribbean Sea
1
Chesapeake Bay (Md. and Va.)
1
Chesapeake Bay Watershed
1
Craig
1
Craig (Alaska)
1
Great Salt Lake
1
Great Salt Lake (Utah)
1
Hays County
1
Kendall County
1
Medina County
1
Middle Atlantic States
1
Mississippi River Valley
1
Missouri
1
Nantucket Shoals
1
Native Village of Diomede
1
Nevada
1
New England
1
New Mexico
1
Pyramid Lake
1
Pyramid Lake (Nev.)
1
Saint Croix National Scenic Riverway (Wis. and Minn.)
1
Saint Marys River (Mich. and Ont.)
1
San Francisco Bay
1
San Francisco Bay (Calif.)
1
Susquehanna River
1
Truckee River (Calif. and Nev.)
1
Utah
1
Washoe County
1