U.S. Department of the Interior

U.S. Geological Survey

Scientific Investigations Report 2008–5153

Elevation-Derived Watershed Basins and Characteristics for 

Major Rivers of the Conterminous United States

Elevation-Derived Watershed Basins and 

Characteristics for Major Rivers of the 

Conterminous United States

By S.K. Poppenga and B.B. Worstell

Scientific Investigations Report 2008–5153

U.S. Department of the Interior

U.S. Geological Survey
U.S. Department of the Interior

DIRK KEMPTHORNE, Secretary

U.S. Geological Survey

Mark D. Myers, Director

U.S. Geological Survey, Reston, Virginia: 2008

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Suggested citation:

Poppenga, S.K., and Worstell, B.B., 2008, Elevation-derived watershed basins and characteristics for major rivers of 

the conterminous United States: U.S. Geological Survey Scientific Investigations Report 2008–5153, 27 p.
iii

Contents

Abstract...........................................................................................................................................................1

Introduction.....................................................................................................................................................1

Methods...........................................................................................................................................................1

Land Cover Characteristics.................................................................................................................3

Population Characteristics..................................................................................................................3

Elevation and Slope Characteristics .................................................................................................7

Other Ancillary Characteristics..........................................................................................................7

The EDNA Watershed Atlas.........................................................................................................................7

The Hypertext Markup Language (HTML) Option (Web browser)................................................7

The 3D Option (Google Earth) .............................................................................................................7

Watershed Layers (Google Earth)....................................................................................................10

Watershed Characteristics (Google Earth) ....................................................................................10

Results ...........................................................................................................................................................10

Discussion.....................................................................................................................................................10

Conclusions...................................................................................................................................................15

References Cited..........................................................................................................................................15

Figures

1. Web image showing geographic information system (GIS) layers for Elevation 

Derivatives for National Applications (EDNA) seamless database .....................................2

2–3. Maps showing:

2. Elevation-derived watersheds for major rivers of the conterminous 

United States ........................................................................................................................3

3. Reach catchments within an elevation-derived watershed ........................................4

4–9. Web images showing:

4. EDNA Watershed Atlas Web portal is accessible in a standard Web 

browser (HTML link) or with a three-dimension option, such as Google 

Earth (KML version link)....................................................................................................16

5. The EDNA Watershed Atlas is accessible from the EDNA Web site .......................17

6. Land cover characteristics for the Chesapeake Bay watershed..............................18

7. Slope characteristics for the Chesapeake Bay watershed .......................................19

8. Population characteristics for the Chesapeake Bay watershed ..............................20

9. Characteristics for the Chesapeake Bay watershed accessible in 

Google Earth .......................................................................................................................21

10–15. Maps showing:

10. Land cover characteristics for the Chesapeake Bay watershed, 1992....................22

11. Land cover characteristics for the Chesapeake Bay watershed, 2001....................23

12. Population characteristics for the Chesapeake Bay watershed, 1990 ....................24

13. Population characteristics for the Chesapeake Bay watershed, 2000 ....................25

14. Elevation characteristics for the Chesapeake Bay watershed .................................26

15. Slope characteristics for the Chesapeake Bay watershed .......................................27
iv

Tables

1. Elevation-derived watersheds for major rivers of the conterminous United States.........4

2. Land cover characteristics, in percent, for elevation-derived watersheds, 1992.............5

3. National Land Cover Data classification schemes, 1992.......................................................7

4. Land cover characteristics, in percent, for elevation-derived watersheds, 2001.............8

5. National Land Cover Data classification schemes, 2001.....................................................10

6. Population characteristics for elevation-derived watersheds, 1990.................................11

7. Population characteristics for elevation-derived watersheds, 2000.................................12

8. Elevation characteristics for elevation-derived watersheds..............................................13

9. Slope characteristics, in degrees, for elevation-derived watersheds..............................14

10. National Inventory of Dams (NID) “Purposes” attribute categories. ................................15

Conversion Factors

Multiply By To obtain

Length

centimeter (cm) 0.3937 inch (in.)

meter (m) 3.281 foot (ft) 

kilometer (km) 0.6214 mile (mi)

kilometer (km) 0.5400 mile, nautical (nmi) 

meter (m) 1.094 yard (yd) 

Area

square meter (m2

) 0.0002471 acre 

square kilometer (km2

) 247.1 acre

square centimeter (cm2

) 0.001076 square foot (ft2)

square meter (m2

) 10.76 square foot (ft2) 

square centimeter (cm2

) 0.1550 square inch (ft2) 

square kilometer (km2

) 0.3861 square mile (mi2)

Flow rate

cubic meter per second (m3

/s) 70.07 acre-foot per day (acre-ft/d) 

cubic meter per second (m3

/s) 35.31 cubic foot per second (ft3/s)

cubic meter per second per 

square kilometer [(m3

/s)/km2]

91.49 cubic foot per second per square 

mile [(ft3/s)/mi2]

cubic meter per second (m3

/s) 22.83 million gallons per day (Mgal/d) 

Vertical coordinate information is referenced to the North American Vertical Datum of 1988 

(NAVD 88).

Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83). 

Elevation, as used in this report, refers to distance above the vertical datum.
Elevation-Derived Watershed Basins and Characteristics 

for Major Rivers of the Conterminous United States

By S.K. Poppenga1 and B.B. Worstell2

Abstract

The U.S. Geological Survey Earth Resources Observation 

and Science Center Topographic Science Project has developed elevation-derived watershed basins and characteristics 

for major rivers of the conterminous United States. Watershed 

basins are delineated upstream from the mouth of major rivers 

by using the hydrologic connectivity of the Elevation Derivatives for National Applications (EDNA) seamless database. 

Watershed characteristics are quantified by integrating 

ancillary geospatial datasets, including land cover, population, slope, and topography, with elevation-derived watershed 

boundaries. The results are published in an online EDNA 

Watershed Atlas at http://edna.usgs.gov/watersheds. The atlas 

serves as a framework for evaluating and analyzing the physical, biological, and anthropogenic status of watersheds.

Introduction

In an effort to evaluate and analyze the health of the 

Nation’s watersheds, the U.S. Geological Survey Earth 

Resources Observation and Science Center Topographic 

Science Project has developed elevation-derived watershed 

basins and characteristics for major rivers of the conterminous 

United States. Watershed basins are derived from hydrologically conditioned digital elevation models (DEMs) because 

the DEMs are precise, consistent, and unaffected by visual 

interpretations of cartographic data. Watershed characteristics 

are selected to provide metrics for land cover distributions, 

population density, topography, and impoundments for each 

watershed. This report describes the methods used to develop 

elevation-derived watershed basin delineations and characteristics and the watershed analysis capabilities within the Elevation Derivatives for National Applications (EDNA) Watershed 

Atlas (http://edna.usgs.gov/watersheds).

The hydrologic framework that facilitates analyses for 

the nationally integrated inventory of watershed basins and 

1

U.S. Geological Survey.

2

SGT, contractor to the U.S. Geological Survey. Work performed under 

USGS contract 08HQCN0005.

characteristics is the EDNA database (Franken and others, 

2001). EDNA is a nationally consistent, 30-meter resolution, 

multilayered database in which hydrologic flow representation 

and stream network connectivity are derived from the National 

Elevation Dataset (NED) (Gesch and others, 2002). The NED 

is a DEM of the land surface and is the basis for the EDNA 

database in that the DEM is a representation of the drainage 

surface of the United States. A geographic information system 

(GIS) is used to create hydrologic derivative layers by filling 

depressions in the DEM (from the NED), calculating flow 

direction and flow accumulation, and creating synthetic flow 

channels and reach catchments.

The EDNA is assembled as a seamless database with 

vertically consistent, hydrologic geospatial layers including hydrologically conditioned DEMs, flow direction, flow 

accumulation, synthetic flow channels, reach catchments, 

sinks, slope, aspect, and compound topographic index (CTI; 

fig. 1). Flow direction in EDNA channels is always from a 

higher elevation to a lower elevation, and the reach catchments always follow the drainage divide (Verdin and Greenlee, 

2003). On the basis of this consistent information available on 

a national scale, watershed basins are delineated, and watershed characteristics are summarized for land cover, population, 

drainage area, minimum, maximum, and average elevation 

and slope for major rivers of the conterminous United States 

(fig. 2). The ability to access EDNA data layers as a seamless 

database facilitates the development of elevation-derived 

watersheds and characteristics.

Methods

An algorithm is written to delineate watersheds (contributing area) from any point in the United States by using 

EDNA’s nationwide hydrologic connectivity. The underlying functionality of the watershed delineation is built on the 

EDNA reach catchments. During EDNA database development, reaches based on a 5,000-pixel drainage area are created 

from the DEM, and subsequently a catchment is produced 

for each one of the reaches (fig. 3). Watershed basins are 

delineated by selecting an outlet catchment (point) and 

automatically aggregating the upstream catchments (Kost 
Figure 1. Geographic information system (GIS) layers for Elevation Derivatives for National Applications (EDNA) seamless database 

(available online at http://edna.usgs.gov/Edna/datalayers.asp).

2 Elevation-Derived Watershed Basins and Characteristics for Major Rivers of the Conterminous United States

and others, 2001). The output is a polygon that represents the 

contributing area of a watershed basin.

Elevation-derived watersheds are delineated by using the 

EDNA watershed tool, which is Web-enabled and contains 

integration capabilities for placing an outlet point for watershed delineation. The outlet location for each major river 

is interactively determined by using existing hydrography 

datasets with named rivers. The corresponding EDNA stream 

reach is used to seed an outlet point for the EDNA watershed 

tool, which processes the outlet point to create a delineation 

for the contributing area upstream from the point. Elevationderived watersheds are delineated for 77 major rivers of the 

United States from this tool (table 1 and fig. 2). The combined 

watersheds for these river systems cover most of the land 

surface of the conterminous United States. Each watershed 

delineation serves as a zone mask for computing and summarizing statistics for the watershed.

Watershed characterization includes methods that 

describe and define the physical, biological, and anthropogenic status of the watershed basin. The watershed characteristics summarized include land cover, population, elevation, 

and slope. Additional summaries include information about 

dams in the watersheds. To produce these characteristics, we 

used ESRI’s ArcMap to convert watershed basins (polygons) 

to rasters (grids). Ancillary geospatial data are overlaid with 

each watershed grid to extract coincident land cover, population, drainage area, elevation, and slope grids. Watershed 

characteristics are summarized by quantifying the pixels in 

each contributing area by using the extracted coincident grids. 

The derived spatial and temporal characteristics describe the 

land cover (1992 and 2001), average population density (1990 

and 2000, persons per square kilometer), drainage area (square 

kilometers), minimum and maximum elevation (meters), and 

minimum and maximum slope (degrees). The methods and 
Figure 2. Elevation-derived watersheds for major rivers of the conterminous United States (available online at 

http://edna.usgs.gov/watersheds/html_index.htm).

Methods 3

examples for each of these characteristics are further described 

in the sections that follow.

Land Cover Characteristics

Distribution of land cover classes are computed for each 

watershed by using data from the 1992 and 2001 National 

Land Cover Data (NLCD; U.S. Geological Survey, 2007). 

These datasets are developed at 30-meter resolution. Each 

dataset was mapped with different methods and slightly different classes. The 1992 NLCD contains categories of land cover 

types, which are derived classifications of Landsat Thematic 

Mapper imagery from the mid-1990s; the 2001 NLCD 

contains classes, which are derived classifications of multiseason Landsat 5 and Landsat 7 imagery. The percentage of 

each NLCD category is computed and classified for each 

watershed on the basis of the Anderson Classification scheme. 

The 1992 and 2001 land cover characteristics are summarized 

in tables 2–5.

Population Characteristics

Population data from the Center for International Earth 

Science Information Network (CIESIN) are characterized for 

each watershed. The CIESIN is a nongovernmental organization at Columbia University, New York City. It develops 

datasets and analysis capabilities for studying a wide range 

of human and environmental interactions. CIESIN datasets 

include human population estimates for 1990 and 2000 called 

the Gridded Population of the World (GPWv3; Gridded 

Population of the World Version3, 2005). The dataset provides 

estimates of human population density in units of persons per 

square kilometer.
Figure 3. Reach catchments within an elevation-derived 

watershed.

Table 1. Elevation-derived watersheds for major rivers of the 

conterminous United States.

Altamaha Hudson Red River

Apalachicola Kansas Rio Grande

Arkansas Kennebec Roanoke

Atchafalaya Klamath Rogue

Biloxi Lake Champlain Sabine

Black Merrimack Sacramento/San Joaquin

Brazos Mississippi Saint John

Calcasieu Missouri Saint Johns

Caloosahatchee Mobile Salinas

Cape Fear Navidad San Francisco Bay

Chehalis Neuse San Gabriel

Chesapeake Bay Nueces Santa Maria

Cheyenne Ochlockonee Santa Ynez

Choctawhatchee Ogeechee Santee

Chowan Ohio Satilla

Colorado Pajaro Savannah

Colorado, Texas Pamlico Souris

Columbia Pascagoula Suwannee

Connecticut Peace Tampa Bay

Delaware Pearl Trinity

Edisto Pee Dee Umpqua

Eel Penobscot Waccamaw

Escambia Platte Withlacoochee

Everglades Puget Sound Yellow

Great Basin Rainy Yellowstone

Great Lakes Red

4 Elevation-Derived Watershed Basins and Characteristics for Major Rivers of the Conterminous United States

The GPWv3 dataset is developed globally using census 

data specific to each country. These country-specific data 

are converted to a uniform 2.5-arc-minute resolution raster 

dataset. Population density values for each census unit are 

developed for each country. These data are overlaid on a 

2.5-arc-minute grid to determine proportions of density values 

per grid cell (Deichmann and others, 2001).

GPWv3 population density datasets for 1990 and 2000 

are used for estimating average population density for major 

U.S. watersheds. These data are projected into the USGS 

Albers Equal Area projection at a resolution of 3,845 meters 

by 3,845 meters. Population density samples (cells) for each 

watershed are summed and divided by the total number of 

cells in the watershed. The 1990 and 2000 population characteristics are summarized in table 6 and table 7, respectively.
Table 2. Land cover characteristics, in percent, for elevation-derived watersheds, 1992 (National Land Cover Data (NLCD) from U.S. Geological Surv

classification schemes in table 3.—Continued

Watersheds 11 12 21 22 23 31 32 33 41 42 43 51 61 71 81 82 83 

Altamaha 1.2 0 1.7 0.4 0.8 0.1 0.3 5.4 21.9 24.8 10.8 0 0 0 8.1 15.5 0 

Apalachicola 2.0 0 1.6 .4 .9 0 .1 4.2 21.8 17.5 17.6 0 0 .1 8.6 15.5 0 

Arkansas 1.2 0 .6 .2 .4 .3 0 .1 8.7 4.4 1.6 5.6 0 44.6 11.2 6.9 13.0 

Atchafalaya 6.2 0 .9 .1 .7 0 0 .2 3.5 3.4 1.4 0 0 .4 10.4 20.5 2.9 

Biloxi 3.1 0 1.6 .5 1.1 0 0 3.3 2.2 40.9 14.3 0 0 0 8.4 2.6 0 

Black .4 0 1.2 .3 .7 0 .1 2.9 10.6 23.7 8.8 0 0 0 3.1 28.8 0 

Brazos 1.6 0 .5 .2 .5 .5 .1 0 7.2 4.5 .4 14.5 0 26.3 15.5 21.7 5.5 

Calcasieu 5.7 0 1.4 .3 1.0 .2 .1 4.2 7.6 28.1 11.3 0 0 .4 9.3 4.2 8.1 

Caloosahatchee 3.0 0 8.9 1.9 1.1 .1 .1 1.0 0 9.5 0 2.1 6.0 14.9 13.6 10.5 0 

Cape Fear 1.5 0 2.6 .8 1.3 .2 .1 1.1 20.4 24.9 9.6 0 0 0 7.3 15.8 0 

Chehalis 1.6 0 .9 0 .6 .1 0 6.6 18.9 45.1 16.0 1.0 .2 .5 6.7 .6 .1 

Chesapeake Bay 7.6 0 2.4 .2 1.1 0 .4 .6 40.7 5.6 11.7 0 0 0 20.7 6.2 0 

Cheyenne .5 0 .1 0 .1 .9 .1 0 .5 10.2 0 12.9 0 65.8 2.7 .5 2.9 

Choctawhatchee 2.9 0 .5 .1 .5 0 0 4.7 13.5 21.8 20.9 0 0 0 8.6 16.2 0 

Chowan 1.4 0 .9 0 .6 0 0 2.3 25.4 15.8 15.1 0 0 0 9.9 16.6 0 

Colorado .4 0 .3 0 .2 3.8 .1 0 2.9 19.4 .6 58.9 0 11.0 1.1 .7 .2 

Colorado-Texas .7 0 .5 .2 .5 .7 0 0 3.1 7.8 0 42.0 0 25.9 3.5 13.1 1.7 

Columbia 1.3 .1 .4 0 .4 1.6 0 1.4 1.3 37.4 1.2 30.3 .3 10.5 4.5 1.5 4.8 

Connecticut 2.3 0 3.2 .5 1.7 .2 .1 .6 38.0 14.7 24.0 .2 0 0 2.3 6.4 0 

Delaware 8.2 0 5.6 1.2 1.9 0 .5 .2 35.4 4.1 14.0 0 0 0 16.7 6.7 0 

Edisto 2.9 0 .7 .3 .3 .1 .1 4.5 10.8 26.5 9.3 0 0 0 2.6 23.0 0 

Eel .4 0 .1 0 .1 .7 0 .3 5.8 50.2 10.0 12.1 0 19.2 1.0 0 0 

Escambia .4 0 .3 0 .2 0 .1 4.3 11.2 35.9 25.2 0 0 0 6.9 8.4 0 

The Everglades 13.7 0 3.1 .7 .9 .1 0 .7 0 4.3 0 .3 3.3 13.6 5.7 12.9 0 

Great Basin 2.0 0 .2 0 .2 9.3 .1 0 .9 10.2 .3 67.5 0 5.7 2.3 .4 .5 

Great Lakes 31.8 0 1.3 .6 .7 0 .1 .2 19.9 3.8 4.6 0 0 .9 9.6 17.2 0 

Hudson 3.2 0 3.5 1.1 1.3 0 .1 0 40.8 10.4 19.4 0 0 0 13.2 3.8 0 

Kansas 0.7 0 0.2 0.1 0.3 0.1 0 0 1.9 0.1 0.1 0.6 0 42.8 8.1 25.5 16.7 

Kennebec 6.0 0 .7 .1 .6 .1 0 2.1 30.3 22.3 27.4 .3 0 0 1.9 4.4 0 

Klamath 1.5 0 .1 0 .2 .7 0 .6 1.2 62.2 3.1 14.1 0 8.3 2.8 .5 2.5 

Lake Champlain 7.7 0 1.0 .3 1.0 .1 .1 .3 38.3 13.1 16.4 .1 0 0 6.6 11.8 0 

Merrimack 4.9 0 6.2 .9 3.0 .1 .1 .4 30.8 17.3 23.6 .1 0 0 1.6 5.0 0 

Mississippi 1.48 0 .76 .16 .46 .2 .08 .34 16.88 6.10 4.04 4.78 0 25.72 13.0 15.3 6.98 

Missouri 1.1 0 .3 .1 .3 .3 0 .3 3.2 5.6 .2 8.5 0 42.3 9.0 15.1 8.2 

Mobile 1.6 0 .8 .2 .5 0 .2 2.3 25.8 19.3 24.3 0 0 0 10.3 7.7 0 

Navidad 7.5 0 .4 .2 .4 .3 .1 .1 13.5 7.4 .3 11.0 0 14.0 21.8 17.7 .5 

Neuse 3.3 0 2.8 .6 1.3 .1 .1 .9 16.1 19.3 7.0 0 0 0 6.2 23.6 0 

Nueces 3.3 0 .6 .5 .6 .5 .1 0 6.9 12.5 .3 38.5 0 13.2 11.4 8.7 1.1 

Ochlockonee 1.6 0 1.6 .2 .4 0 .1 8.9 2.6 23.7 7.3 .3 .3 1.9 3.2 19.2 0 

Ogeechee 1.3 0 .8 .3 .5 .1 0 5.6 10.8 26.9 7.4 0 0 0 3.0 26.3 0 

Ohio 1.4 0 1.6 .2 .7 0 .3 .3 43.4 4.2 7.6 0 0 .1 19.2 19.4 0 

Pajaro .1 0 1.5 .2 .6 1.6 0 0 3.7 12.7 7.5 16.6 3.7 40.3 7.4 3.8 0 

Pamlico 1.5 0 1.7 .2 .7 .1 .1 1.4 21.9 20.2 8.3 0 0 0 7.9 21.0 0 

Pascagoula 1.1 0 .5 .1 .4 0 0 3.6 11.1 32.6 22.7 0 0 0 11.4 5.4 0 

Peace 4.1 0 5.7 1.4 1.4 .5 1.2 .6 0 6.8 0 1.1 10.6 26.9 9.8 6.4 0 
Table 2. Land cover characteristics, in percent, for elevation-derived watersheds, 1992 (National Land Cover Data (NLCD) from U.S. Geological Surv

classification schemes in table 3.—Continued

Watersheds 11 12 21 22 23 31 32 33 41 42 43 51 61 71 81 82 83 

Pearl 16.3 0 1.9 .5 .7 .1 0 .9 11.8 21.3 12.3 0 0 .1 14.1 4.7 0 

Pee Dee .9 0 2.3 .4 1.1 .1 .1 1.2 23.7 17.3 10.8 0 0 0 10.2 20.7 0 

Penobscot 5.7 0 .3 .1 .4 .1 0 2.4 21.3 27.8 34.2 .3 0 0 .4 1.8 0 

Platte .9 .1 .6 .1 .4 .2 0 .1 1.7 6.2 0 11.8 0 50.0 4.6 14.5 3.6 

Puget Sound 16.3 .9 3.6 0 1.2 2.5 0 4.1 8.7 45.1 7.9 2.6 .2 2.4 3.4 .3 .2 

Rainy 9.6 0 .1 0 .3 0 .2 1.1 17.0 10.8 12.4 1.8 0 0 2.4 1.7 .4 

Red 2.1 0 .6 .1 .4 .2 0 .7 14.0 11.3 7.9 5.2 0 16.8 12.3 15.2 7.8 

Red River 3.1 0 .2 .1 .4 0 0 .1 6.7 .2 .1 .2 0 3.4 9.4 57.1 8.3 

Rio Grande .7 0 .2 .1 .3 1.7 0 0 .5 9.8 .1 48.8 0 34.1 1.2 1.9 .1 

Roanoke 2.3 0 1.8 .1 .7 0 .1 1.3 39.1 14.2 12.7 0 0 0 16.3 6.0 0 

Rogue .4 0 .5 0 .3 .2 0 .8 2.1 69.1 11.5 2.9 0 6.4 5.0 .2 .4 

Sabine 4.6 0 .9 .3 1.0 .1 .1 2.3 17.6 15.8 21.9 0 0 .5 20.9 2.1 1.8 

Sacramento/San 

Joaquin

1.6 0 1.6 0 0.6 2.2 0 0.1 3.0 29.3 4.0 13.1 6.0 20.7 6.4 6.3 4.3 

Saint John 3.3 0 .3 0 .3 0 0 3.3 23.8 26.2 33.2 .5 0 0 .3 5.7 0 

Saint Johns 7.6 0 6.8 2.0 1.7 .2 .1 3.7 0 29.9 0 1.3 3.1 9.7 2.7 7.6 0 

Salinas .2 0 .6 .1 .4 3.4 0 0 1.3 12.4 3.7 16.0 .8 47.9 4.9 7.1 .9 

San Francisco 12.3 0 18. .4 4.9 1.0 .1 0 4.7 10.4 8.5 7.5 .4 26.5 1.4 .6 .3 

San Gabriel .6 0 14.4 2.9 5.0 1.7 0 0 .8 13.6 3.2 38.4 .9 9.5 1.4 5.0 .9 

Santa Maria 0 0 .6 .2 .3 5.0 0 0 2.1 14.7 3.8 28.3 1.0 36.3 3.9 3.1 .5 

Santa Ynez .4 0 .7 .2 .3 1.3 .3 0 1.3 15.4 8.3 35.0 .6 29.2 2.9 3.3 .4 

Santee 2.8 0 3.5 .9 1.6 .2 .1 2.1 26.9 24.6 14.2 0 0 0 7.8 10.3 0 

Satilla 1.2 0 .4 .1 .3 0 0 7.6 4.3 37.0 5.5 0 0 0 4.0 21.2 0 

Savannah 3.1 0 1.4 .3 .7 .1 .2 4.7 21.4 29.7 13.1 0 0 0 7.2 10.5 0 

Souris 1.3 0 .2 .1 .4 .4 .1 0 3.2 0 0 1.2 0 26.9 2.0 10.4 42.4 

Suwannee .9 0 1.1 .2 .4 .1 .2 6.7 2.2 32.8 2.6 .5 .1 4.9 4.7 20.3 0 

Tampa Bay 14.6 0 12.3 6.2 4.0 .4 1.1 .9 0 6.5 0 .6 5.7 15.8 4.2 6.6 0 

Trinity 5.4 0 3.8 2.0 2.3 .2 .1 .5 12.4 5.5 9.8 1.4 0 8.7 35.3 5.6 2.6 

Umpqua .6 0 .2 0 .3 .2 0 1.4 3.3 71.0 11.4 2.0 0 4.9 4.5 0 .1 

Waccamaw 1.4 0 .9 .2 .7 .1 .1 1.7 4.1 32.9 5.8 0 0 0 3.7 17.0 0 

Withlacoochee 2.2 0 7.7 .8 .9 .2 .2 3.0 .3 21.9 0 2.3 2.2 16.5 2.5 15.0 0 

Yellow 2.0 0 .4 .1 .7 0 0 6.2 10.5 34.3 18.7 0 0 0 6.6 10.4 0 

Yellowstone .6 .1 .1 0 .1 .5 .1 1.1 .8 12.8 .1 27.0 0 46.9 1.9 .6 3.2 
Table 3. National Land Cover Data classification schemes, 1992 

(from U.S. Geological Survey, 2007).

Classification

11 Open Water

12 Perennial Ice / Snow

21 Low Intensity Residential

22 High Intensity Residential

23 Commercial / Industrial / Transportation

31 Bare Rock / Sand / Clay

32 Quarries / Strip Mines / Gravel Pits

33 Transitional

41 Deciduous Forest

42 Evergreen Forest

43 Mixed Forest

51 Shrubland

61 Orchards / Vineyards / Other

71 Grasslands / Herbaceous

81 Pasture / Hay

82 Row Crops

83 Small Grains

84 Fallow

85 Urban / Recreational Grasses

91 Woody Wetlands

92 Emergent Herbaceous Wetlands

Methods 7

Elevation and Slope Characteristics

Elevation statistics are computed by using the EDNA 

filled elevation layer, a hydrologically conditioned DEM that 

contains no depressions. Zonal statistics are derived for each 

watershed drainage area and include minimum, maximum, and 

average elevation. Statistics for EDNA slope are computed in 

the same manner. The elevation and slope characteristics are 

summarized in table 8 and table 9, respectively. Watershed 

basin characteristics derived from EDNA are among the most 

time-consuming to generate because of the size of the nationwide elevation and slope grids, each exceeding 55 gigabytes.

Other Ancillary Characteristics

The National Inventory of Dams (NID) database contains 

an inventory of more than 79,000 dams in the United States. 

The database is maintained by the U.S. Army Corps of 

Engineers and used for inspection, safety, and other applications by Federal and State agencies. A dam is included in the 

NID database if it is a potential hazard or exceeds a height 

of 25 feet with 15 acre-feet of storage, or exceeds a height 

of 6 feet with 50 acre-feet of storage. Because dams can be 

used for multiple purposes, they are categorized as such in 

the NID database with a “Purposes” attribute (table 10). For 

each “Purpose” category assigned to each dam in a watershed, 

the percentage of dams used for each category is computed. 

Because some dams have multiple purposes, the percentages 

for the number of dams in a watershed do not always equal 

100 percent. For example, a watershed with 100 dams might 

have 100 percent used for recreation, 60 percent used for flood 

control, and 1 percent used for hydroelectric generation.

The EDNA Watershed Atlas

The elevation-derived watershed basins and characteristics for major rivers of the conterminous United States are 

published in an online EDNA Watershed Atlas. The atlas 

serves as a framework for geographic analyses of watershed 

basins and characteristics and is a valuable tool for evaluating 

change within watersheds. The atlas is published in a standard 

Web browser and in a three-dimensional (3D) environment, 

such as Google Earth. The EDNA Watershed Atlas portal is 

at http://edna.usgs.gov/watersheds/ (fig. 4) and is accessible 

through the EDNA Web site at http://edna.usgs.gov (fig. 5).

The Hypertext Markup Language (HTML) Option 

(Web browser)

By selecting the HTML link on the EDNA Watershed 

Atlas portal (fig. 4), the elevation-derived watershed basins 

and characteristics can be accessed exclusively in a standard 

Web browser. Each watershed name is a Web link to that 

watershed’s characteristics. For example, selection of the 

Chesapeake Bay watershed (link) redirects to the watershed 

characteristics for the Chesapeake Bay (fig. 6). Additional 

Chesapeake Bay watershed characteristics, such as land 

cover, population, elevation, slope, or dams can be accessed 

by selecting one of the EDNA watershed characteristics links 

(left side in fig. 6). Selection of the Slope link redirects to the 

Chesapeake Bay watershed slope characteristics (fig. 7). Other 

watersheds can be accessed by selecting the Return to Watershed Index link to return to the EDNA Watershed Atlas portal.

The 3D Option (Google Earth)

The EDNA Watershed Atlas can be accessed in 3D by 

selecting the KML link from the Watershed Atlas portal at 

http://edna.usgs.gov/watersheds/ (fig. 4). The 3D atlas portal 

looks similar to the Web portal; however, selection of the 3D 

links will result in a Keyhole Markup Language (KML) file 

loaded into Google Earth. There are two options in Google 

Earth: Watershed Layers and Watershed Characteristics.
Table 4. Land cover characteristics, in percent, for elevation-derived watersheds, 2001 (National Land Cover Data (NLCD) from U.S. Geological Surv

classification schemes in table 5.—Continued

Watersheds 11 12 21 22 23 24 31 41 42 43 52 71 81 

Altamaha 1.2 0 5.9 2.6 0.7 0.3 0.7 20.0 24.8 5.1 0.9 9.7 10.6 

Apalachicola 1.9 0 5.5 2.6 .7 .4 .3 19.7 24.0 3.9 4.0 5.5 9.0 

Arkansas 1.2 0 3.2 .9 .3 .1 .3 8.9 5.4 .6 7.1 41.8 8.6 

Atchafalaya 5.5 0 .5 2.9 .4 .2 .2 0 2.3 .6 1.3 1.1 6.8 

Biloxi 3.1 0 7.7 4.2 1.3 .4 .4 0 37.9 1.2 13.2 2.8 4.6 

Black .4 0 4.8 1.2 .3 .1 .1 3.8 20.6 1.5 5.0 8.4 8.6 

Brazos 1.0 0 3.4 .8 .3 .1 .2 5.4 4.9 .7 19.8 30.0 8.9 

Calcasieu 5.2 0 2.3 4.5 .5 .3 .2 .1 26.7 2.8 14.2 6.6 7.8 

Caloosahatchee 2.1 0 8.2 5.8 1.1 .3 .1 0 3.4 0 12.8 1.3 17.5 

Cape Fear 1.4 0 6.0 2.9 .9 .3 .3 15.6 19.0 4.1 3.7 9.1 9.2 

Chehalis 1.4 0 4.6 1.6 .5 .2 2.3 4.1 51.1 6.0 11.2 5.2 4.8 

Chesapeake Bay 7.3 0 4.5 2.3 .9 .3 .6 42.2 6.5 5.4 .6 .3 17.7 

Cheyenne .6 0 .7 .2 .1 0 1.3 .3 11.5 .1 16.3 62.8 1.0 

Choctawhatchee 2.9 0 5.0 1.0 .3 .1 .2 8.1 29.6 5.9 13.8 1.6 8.6 

Chowan 1.1 0 2.0 .5 .1 0 1.6 25.1 26.5 3.2 .7 1.6 11.0 

Colorado .5 .1 .7 .5 .2 0 3.3 3.4 19.8 .4 61.1 7.1 1.3 

Colorado-Texas .5 0 2.1 .5 .2 .1 .2 2.8 5.2 .3 57.5 15.6 2.5 

Columbia 1.2 0 1.4 .7 .3 .1 .9 .5 36.5 .5 35.8 8.9 2.1 

Connecticut 2.0 0 4.5 2.7 1.4 .3 .2 37.2 17.7 21.2 1.4 .2 5.1 

Delaware 7.9 0 6.8 4.4 2.2 1.0 .9 38.5 3.5 4.4 .2 .1 11.7 

Edisto 2.6 0 4.1 1.1 .2 .1 .1 8.1 25.4 2.6 2.9 11.7 7.9 

Eel .5 0 3.1 .1 .1 0 .4 5.2 48.8 7.1 24.4 9.6 .6 

Escambia .7 0 3.9 .6 .1 0 .2 14.7 32.5 10.0 11.3 1.0 8.8 

The Everglades 12.0 0 4.1 1.8 .6 .2 .1 0 2.0 0 3.9 .9 11.7 

Great Basin 1.8 0 .7 .5 .2 0 6.9 1.6 10.9 .2 69.5 4.1 1.8 

Great Lakes 34.0 0 3.5 2.3 .8 .3 .3 17.8 4.4 2.4 1.1 2.1 6.0 

Hudson 3.1 0 5.5 2.1 1.0 .4 .1 39.2 10.0 9.9 2.0 .6 10.8 

Kansas .7 0 3.5 .7 .2 .1 .1 2.4 0 0 0 39.1 3.4 

Kennebec 5.6 0 2.3 1.1 .4 .1 .5 23.9 20.3 28.2 6.3 .8 2.5 

Klamath 1.7 0 1.7 .3 0 0 .9 .8 55.2 1.8 21.4 8.9 2.3 

Lake Champlain 7.4 0 3.1 1.4 .6 .1 .1 33.1 15.8 14.8 1.7 .6 10.4 

Merrimack 4.4 0 5.4 5.0 3.6 0.8 0.4 28.4 19.2 20.1 1.3 0.3 4.6 

Mississippi 1.6 0 3.5 1.3 .4 .1 .3 15.6 5.2 1.1 6.8 24.9 9.5 

Missouri 1.2 0 2.3 .6 .2 .1 .5 3.2 5.9 .1 10.6 41.5 6.8 

Mobile 1.9 0 4.9 1.4 .4 .2 .3 26.8 19.9 9.5 7.3 2.3 12.2 

Navidad 6.9 0 4.4 .5 .2 .1 .2 7.6 4.7 .5 9.4 2.6 33.3 

Neuse 3.4 0 7.6 2.7 1.0 .3 .1 12.9 14.7 4.0 1.8 7.9 7.3 

Nueces 2.7 0 3.3 1.5 .5 .2 .5 4.0 6.8 .2 45.3 9.0 13.9 

Ochlockonee 1.0 0 4.6 1.1 .2 .1 .2 8.0 26.1 7.8 .3 6.1 3.9 

Ogeechee .6 0 4.7 1.5 .4 .1 .3 11.8 24.3 4.6 1.4 11.2 5.9 

Ohio 1.5 0 5.8 2.1 .7 .3 .2 46.2 2.5 2.1 .9 2.3 15.3 

Pajaro .2 0 6.2 2.0 1.5 .3 .2 0 7.0 14.1 24.9 34.1 1.1 

Pamlico 1.5 0 5.6 1.4 .5 .2 .1 17.9 18.8 4.4 2.4 7.9 9.2 

Pascagoula 1.3 0 4.4 .9 .3 .1 .1 6.8 30.2 14.6 13.1 1.0 10.3 

Peace 3.6 0 7.2 2.7 .9 .3 1.5 0 2.0 0 2.6 4.9 26.5 
Table 4. Land cover characteristics, in percent, for elevation-derived watersheds, 2001 (National Land Cover Data (NLCD) from U.S. Geological Surv

classification schemes in table 5.—Continued

Watersheds 11 12 21 22 23 24 31 41 42 43 52 71 81 

Pearl 16.2 0 4.3 2.2 .7 .3 .2 5.2 17.3 6.3 10.0 1.1 10.9 

Pee Dee .8 0 6.4 2.0 .5 .2 .1 22.7 14.5 2.7 2.2 8.2 14.4 

Penobscot 4.6 0 1.4 .6 .2 .1 .5 16.1 22.5 33.1 7.0 .7 .9 

Platte .8 .1 2.2 .8 .3 .1 .4 .9 7.0 .1 15.5 46.8 1.3 

Puget Sound 15.0 .9 4.1 4.2 1.6 .7 3.2 2.6 43.8 6.6 7.6 3.1 2.9 

Rainy 9.1 0 .8 .2 0 0 .2 31.4 21.2 .3 3.2 1.0 1.4 

Red 2.0 0 3.3 1.4 .2 .1 .2 10.4 14.7 3.6 14.0 19.6 7.4 

Red River 4.1 0 3.9 .5 .1 0 0 7.7 .9 0 .2 4.5 8.3 

Rio Grande .5 0 1.0 .6 .2 .1 1.0 .8 10.0 .1 63.7 18.2 1.1 

Roanoke 2.0 0 4.6 1.7 .4 .2 .3 41.8 13.0 3.9 2.0 3.5 18.4 

Rogue .3 0 2.7 .9 .3 .1 .5 .2 65.5 2.6 18.6 3.6 3.0 

Sabine 4.1 0 3.7 3.1 .5 .2 .1 5.9 21.7 6.6 8.4 5.7 15.6 

Sacramento/San 

Joaquin

1.5 0 2.9 1.2 1.1 .2 2.6 1.4 27.1 1.5 17.8 20.5 2.8 

Saint John 2.8 0 .8 .4 .1 0 .5 15.9 20.9 33.0 10.1 .8 1.0 

Saint Johns 6.7 0 9.0 4.2 1.3 .4 .2 .7 24.1 .7 2.2 8.3 10.3 

Salinas .3 0 5.0 .7 .5 .1 2.4 0 5.2 8.8 29.4 37.4 1.3 

San Francisco 12.0 0 8.1 7.7 14.0 4.2 0 0 4.6 17.7 11.5 18.2 0.2 

San Gabriel .6 0 11.6 11.9 13.6 2.1 .6 0 10.0 1.6 31.1 12.2 1.5 

Santa Maria 0 0 2.6 .8 .4 0 2.6 0 8.7 8.4 51.2 17.3 1.7 

Santa Ynez .5 0 4.1 1.0 .6 0 .3 0 15.8 13.5 41.4 15.7 1.8 

Santee 2.9 0 7.8 3.5 1.0 .5 .6 31.3 19.8 2.0 1.3 6.9 15.4 

Satilla .8 0 4.3 1.5 .3 .1 .1 3.6 30.5 2.7 1.5 11.3 4.9 

Savannah 3.1 0 5.3 1.9 .5 .2 .9 25.6 25.5 2.6 1.2 10.1 12.0 

Souris 3.2 0 4.2 .5 .1 0 .1 2.3 0 0 0 20.9 8.4 

Suwannee .6 0 4.6 1.1 .2 .1 .2 4.0 26.8 5.0 .8 11.7 7.8 

Tampa Bay 13.4 0 13.2 9.5 5.9 1.9 1.6 0 3.8 0 2.3 3.8 10.4 

Trinity 5.1 0 6.5 5.5 3.2 1.5 .4 7.5 6.2 3.5 3.9 21.7 19.6 

Umpqua .5 0 2.2 .4 .2 .1 .6 .5 66.8 5.8 12.3 4.6 5.1 

Waccamaw 1.3 0 4.8 1.7 .4 .1 .1 1.2 21.2 1.8 3.4 11.7 .8 

Withlacoochee 1.4 0 9.8 2.6 .8 .1 .3 .1 19.6 0 3.0 3.0 21.6 

Yellow 2.3 0 6.3 .9 .2 .1 .3 2.4 44.5 4.9 10.0 3.9 7.3 

Yellowstone .5 0 .6 .2 .1 0 1.0 .2 12.6 0 34.5 42.2 1.6 
Table 5. National Land Cover Data classification schemes, 2001 

(from U.S. Geological Survey, 2007).

Classification

11 Open Water

12 Perennial Ice / Snow

21 Developed, Open Space

22 Developed, Low Intensity

23 Developed, Medium Intensity

24 Developed, High Intensity

31 Barren Land

32 Unconsolidated Shore

41 Deciduous Forest

42 Evergreen Forest

43 Mixed Forest

51 Dwarf Shrub

52 Scrub/Shrub

71 Grasslands/Herbaceous

72 Sedge Herbaceous

73 Lichens

74 Moss

81 Pasture/Hay

82 Cultivated Crops

90 Woody Wetlands

95 Emergent Herbaceous Wetlands

10 Elevation-Derived Watershed Basins and Characteristics for Major Rivers of the Conterminous United States

Watershed Layers (Google Earth)

In Google Earth, Watershed Layers contains folders 

with integrated characteristics similar to a GIS (including 

transparency). The Watershed Layers folders include watershed boundary, elevation, land cover, and EDNA synthetic 

channels (streams). The Boundary is a polygon generated by 

the watershed tool by using the EDNA database and represents 

the watershed basin in that it follows the drainage divide. 

The Elevation folder provides topographic information and 

is derived from the EDNA database. The Land Cover folder 

contains 1992 and 2001 land cover distributions. The Streams

folder contains mean annual streamflow in cubic meters per 

second for the EDNA synthetic streams. Some of the channels 

in larger watersheds are generalized because of software 

limitation of vertices. The Population folder contains 1990 

and 2000 average population densities. The Watershed Layers

folders that contain temporal data, such as Population, can be 

independently toggled to determine change within the watershed (fig. 8).

Watershed Characteristics (Google Earth)

In Google Earth, Watershed Characteristics is a gateway 

to the elevation-derived watershed summary statistics. Selection of the link (either under the Temporary Places folder or 

the placemark in the center of the display window) accesses 

a Web link where the characteristics are available for analysis 

(fig. 9).

Results

Elevation-derived watershed basins and characteristics 

for major rivers of the conterminous United States contain 

characteristics for 77 watersheds. We have chosen to discuss 

the results of the elevation-derived watershed characteristics 

for the Chesapeake Bay only.

Land cover (1992) characteristics summarized for the 

Chesapeake Bay watershed indicate that the elevation-derived 

watershed basin primarily consists of forest, cropland, and 

pasture (fig. 10). Located in the highly urbanized eastern part 

of the country, the Chesapeake Bay watershed is composed 

of 3.9 percent urban land cover. Transitional and barren land 

account for a small percentage of this watershed area. Land 

cover (2001) characteristics generated from NLCD (U.S. 

Geological Survey, 2007) indicate the watershed still primarily 

consists of forest, cropland, and pasture (fig. 11).

In 1990, the average population density for the Chesapeake Bay watershed was 86.3499 persons per square kilometer (fig. 12). In 2000, the average population density had 

increased to 95.0975 persons per square kilometer (fig. 13). 

This direct spatial and temporal comparison is valuable for 

determining population change within a watershed and for 

evaluating population effects on watersheds.

The drainage area for the Chesapeake Bay watershed is 

174,590 square kilometers with the minimum elevation at sea 

level and a maximum elevation of 1,481.10 meters (fig. 14). 

The minimum slope for the Chesapeake Bay watershed is 

0 degrees, and the maximum slope is 69.3009 (fig. 15).

Discussion

The EDNA watershed delineation tool provided an 

avenue to delineate 77 watersheds that constitute the EDNA 

Watershed Atlas. The watershed delineation tool, however, 

is designed to create a watershed from any point within the 

conterminous United States. Therefore, additional watersheds 

and their characteristics can be added to the EDNA Watershed 

Atlas.

 The number of watershed characteristics was limited by 

time and budgetary constraints. Those characteristics included 

in the EDNA Watershed Atlas are land cover, population, 

drainage area, elevation, slope, and other ancillary data including dams. After the development of the EDNA Watershed 
Table 6. Population characteristics for elevation-derived watersheds, 1990 (persons per square kilometer; from Gridded Population of 

the World, Version 3, 2005).

Watershed Minimum Maximum Mean Watershed Minimum Maximum Mean

Altamaha 2.444 1,999.390 50.3785 Ohio 0 3,816.750 48.5199

Apalachicola 1.165 1,999.390 53.6451 Pajaro .540 1,252.090 50.1417

Arkansas .094 1,623.850 14.1808 Pamlico 6.936 993.684 39.8028

Atchafalaya 2.086 781.483 24.4898 Pascagoula 2.805 1,069.560 19.6377

Biloxi 6.484 1,608.420 87.9239 Peace 3.082 1,023.800 54.9626

Black 5.371 691.320 30.1817 Pearl 1.365 4,599.430 57.1864

Brazos .150 1,571.540 15.9799 Pee Dee 5.371 1,368.370 47.4044

Calcasieu 2.073 870.525 22.4073 Penobscot 0 320.941 7.4835

Caloosahatchee 1.824 1,256.530 71.6347 Platte .032 3,225.680 14.7907

Cape Fear 4.607 1,490.400 60.3852 Puget Sound .087 9,272.470 108.6190

Chehalis .555 601.184 21.4743 Rainy .001 375.450 1.4961

Chesapeake Bay 0 7,016.260 86.3499 Red .150 1,463.610 12.4867

Cheyenne .063 739.655 2.7312 Red River .498 1,663.220 5.1237

Choctawhatchee 3.110 656.003 22.3388 Rio Grande 0 2,481.360 10.9320

Chowan 3.259 356.272 15.2804 Roanoke 3.324 1,280.440 34.9882

Colorado 0 2,869.010 7.9348 Rogue .553 759.116 16.2251

Colorado-Texas .162 2,014.810 12.4362 Sabine 1.231 1,323.530 23.6667

Columbia 0 2,943.600 9.3127 Sacramento/

San Joaquin

.227 10,889.100 42.8452

Connecticut .380 4,322.990 71.0533 Saint John 0 276.292 5.3935

Delaware 1.515 7,773.130 220.7280 Saint Johns 1.318 1,846.690 99.2333

Edisto 3.116 595.132 23.7199 Salinas .454 2,187.560 22.6844

Eel .398 150.419 4.4740 San Francisco 0 10,889.100 768.4640

Escambia 2.924 818.100 13.7091 San Gabriel .767 5,295.070 607.0420

The Everglades .034 1,813.480 30.8146 Santa Maria .383 1,536.200 26.0551

Great Basin 0 2,558.150 6.2571 Santa Ynez .384 965.969 26.0654

Great Lakes 0 8,365.610 75.4810 Santee .628 1,560.800 69.1434

Hudson .302 29,048.100 124.8820 Satilla 2.065 477.399 13.8041

Kansas 0 2,632.060 8.1808 Savannah 0 1,120.280 33.6838

Kennebec .006 1,064.340 16.9063 Souris .323 938.823 3.1468

Klamath .112 685.914 2.6981 Suwannee .560 867.353 15.4862

Lake Champlain 1.058 1,755.680 28.7681 Tampa Bay 0 2,328.500 334.3530

Merrimack 3.596 3,942.030 135.1700 Trinity 0 3,035.130 122.9840

Mississippi .025 18,495.500 21.4810 Umpqua .553 241.142 7.2061

Missouri 0 3,225.680 7.6948 Waccamaw 5.385 851.236 33.0933

Mobile 1.786 1,592.850 31.7039 Withlacoochee 9.231 702.942 44.4995

Navidad 2.971 1,166.390 11.7183 Yellow 2.924 418.485 16.6305

Neuse 6.691 1,420.200 70.5708 Yellowstone .032 1,109.990 1.7943

Nueces .047 2,908.900 24.8054

Ochlockonee 1.165 1,359.490 22.7346

Ogeechee .232 2,021.140 26.2869

Methods 11
Table 7. Population characteristics for elevation-derived watersheds, 2000 (persons per square kilometer; from Gridded Population of 

the World, Version 3, 2005).

Watershed Minimum Maximum Mean Watershed Minimum Maximum Mean

Altamaha 2.696 2,441.900 65.44810 Ohio 0 3,684.090 52.40120

Apalachicola 1.337 2,441.900 67.20760 Pajaro .564 1,608.660 64.00870

Arkansas .079 1,743.370 16.01490 Pamlico 7.370 1,063.420 44.97360

Atchafalaya 2.425 772.262 25.56950 Pascagoula 3.431 1,014.820 21.99150

Biloxi 8.840 1,299.060 103.67000 Peace 3.160 1,071.340 64.46690

Black 6.483 666.800 31.80700 Pearl 1.136 4,313.740 62.30830

Brazos .150 1,822.000 19.53970 Pee Dee 6.008 1,556.430 56.24530

Calcasieu 2.380 809.783 23.73720 Penobscot .008 315.609 7.44283

Caloosahatchee 3.160 1,341.640 85.85530 Platte .023 3,666.890 18.46410

Cape Fear 5.590 1,555.880 75.80190 Puget Sound .037 9,101.530 128.78000

Chehalis .670 592.890 23.91700 Rainy .003 365.339 1.47902

Chesapeake Bay .149 6,239.380 95.09750 Red .150 1,512.980 13.20550

Cheyenne .068 748.516 3.01630 Red River .466 1,701.230 5.44082

Choctawhatchee 2.523 790.303 25.62640 Rio Grande .023 2,646.880 13.96650

Chowan 6.350 342.324 16.68420 Roanoke 3.146 1,268.650 37.73600

Colorado .002 4,015.190 11.53630 Rogue .642 997.680 19.94330

Colorado-Texas .114 2,147.970 15.24740 Sabine 1.284 1,459.920 26.19910

Columbia .018 2,916.290 11.49250 Sacramento/

San Joaquin

.197 10,671.700 50.48020

Connecticut .398 3,593.310 72.39410 Saint John 0 272.974 5.01735

Delaware 1.498 7,355.590 234.08400 Saint Johns 1.428 2,150.190 124.12300

Edisto 3.576 673.075 27.78680 Salinas .485 2,548.500 28.40280

Eel .387 171.819 4.79963 San Francisco 0 10,671.700 862.94100

Escambia 3.062 905.974 14.97530 San Gabriel .809 5,856.650 692.49800

The Everglades 0 2,150.190 43.63280 Santa Maria .315 1,875.480 31.26730

Great Basin 0 2,618.190 8.07698 Santa Ynez .368 1,029.880 27.52100

Great Lakes 0 8,782.440 78.87440 Santee .717 1,556.430 82.23850

Hudson .328 29,680.500 130.59300 Satilla 2.334 420.262 15.89490

Kansas .238 2,234.420 8.52539 Savannah 0 1,048.880 38.86540

Kennebec .012 964.501 17.07390 Souris .254 952.576 3.03534

Klamath .126 730.727 2.88294 Suwannee .517 900.537 18.93570

Lake Champlain 1.040 1,765.680 30.19020 Tampa Bay 3.659 2,616.070 390.53700

Merrimack 4.205 3,958.670 148.07200 Trinity 0 3,834.090 156.37000

Mississippi .029 19,389.77 23.6513 Umpqua .642 302.227 7.66179

Missouri .023 3,666.890 8.73752 Waccamaw 6.503 832.239 42.76250

Mobile .252 1,577.930 36.10900 Withlacoochee 12.014 705.034 60.97490

Navidad 3.188 1,231.130 12.76340 Yellow 2.523 514.013 22.44070

Neuse 7.409 1,555.880 90.49390 Yellowstone .041 1,135.230 1.96221

Nueces .113 2,942.550 29.68300

Ochlockonee 1.337 1,491.550 27.31190

Ogeechee 0 1,894.220 29.16240

12 Elevation-Derived Watershed Basins and Characteristics for Major Rivers of the Conterminous United States
Table 8. Elevation characteristics for elevation-derived watersheds (EDNA).

Watershed

Area

(square 

kilometers)

Minimum

(meters)

Maximum

(meters) Watershed

Area

(square 

kilometers)

Minimum

(meters)

Maximum

(meters)

Altamaha 36,969.2 0 508.12 Ohio 525,924.0 86.99 2,035.83

Apalachicola 50,579.3 0 1,348.87 Pajaro 3,371.4 0 1,597.36

Arkansas 405,274.0 34.35 4,411.43 Pamlico 8,908.9 0 219.54

Atchafalaya 14,369.3 0 79.80 Pascagoula 24,562.6 0 216.96

Biloxi 1,803.7 0 111.42 Peace 6,247.2 –.33 89.88

Black 4,598.4 .05 131.96 Pearl 44,357.5 0 220.06

Brazos 11,917.4 0 1,446.24 Pee Dee 37,183.6 .53 1,255.77

Calcasieu 9,914.0 0 142.75 Penobscot 21,641.5 0 1,599.24

Caloosahatchee 4,695.2 –.35 48.74 Platte 220,529.0 288.16 4,344.37

Cape Fear 23,501.0 0 332.90 Puget Sound 43,046.8 0 4,390.53

Chehalis 6,039.0 0 1,530.49 Rainy 52,850.2 323.39 669.19

Chesapeake Bay 174,590.0 0 1,481.10 Red 241,261.0 5.80 1,515.60

Cheyenne 65,489.3 492.47 2,205.44 Red River 104,877.0 232.13 720.81

Choctawhatchee 13,669.1 0 210.88 Rio Grande 302,550.0 0 4,361.49

Chowan 12,739.0 0 214.21 Roanoke 25,216.4 0 1,282.29

Colorado 625,052.0 24.72 4,361.41 Rogue 13,376.2 0 2,887.44

Colorado-Texas 109,703.0 0 1,384.99 Sabine 55,122.6 0 234.96

Columbia 542,635.0 0 4,391.03 Sacramento/

San Joaquin

158,164.0 0 4,410.10

Connecticut 27,714.9 0 1,911.87 Saint John 37,349.5 31.86 852.84

Delaware 35,504.2 0 1,265.87 Saint Johns 24,569.9 0 94.50

Edisto 9,792.0 0 207.04 Salinas 11,373.7 0 1,787.82

Eel 9,387.3 0 2,309.04 San Francisco 5,351.7 0 1,322.45

Escambia 11,013.6 0 205.06 San Gabriel 8,182.2 0 3,479.37

The Everglades 23,160.2 –.43 91.43 Santa Maria 4,733.9 0 2,636.60

Great Basin 546,922.0 –69.32 4,415.28 Santa Ynez 2,324.0 0 2,082.83

Great Lakes 328,737.0 32.31 1,401.25 Santee 39,584.5 0 1,802.80

Hudson 34,920.5 0 1,622.57 Satilla 8,988.3 0 112.57

Kansas 155,489.0 220.27 1,817.78 Savannah 27,852.0 0 1,672.74

Kennebec 25,492.5 0 1,912.33 Souris 43,557.2 430.20 821.00

Klamath 41,135.9 0 4,301.61 Suwannee 25,549.0 0 158.74

Lake Champlain 21,325.4 28.87 1,623.40 Tampa Bay 5,149.0 0 80.20

Merrimack 12,845.4 0 1,597.49 Trinity 60,672.3 0 460.78

Mississippi 3,171,588.0 0 4,411.43 Umpqua 12,104.7 0 2,786.40

Missouri 1,325,810.0 119.06 4,344.37 Waccamaw 4,186.0 .53 41.46

Mobile 113,316.0 0 1,280.37 Withlacoochee 5,384.3 0 91.49

Navidad 10,897.7 0 180.70 Yellow 6,126.9 0 160.15

Neuse 14,335.9 0 268.99 Yellowstone 181,388.0 564.45 4,198.78

Nueces 91,967.9 0 740.12

Ochlockonee 6,773.5 0 137.84

Ogeechee 12,118.1 0 225.66

Methods 13
Table 9. Slope characteristics, in degrees, for elevation-derived watersheds (EDNA).

Watershed Minimum Maximum Mean Watershed Minimum Maximum Mean

Altamaha 0 56.723 2.4034 Ohio 0 85.539 6.9332

Apalachicola 0 45.048 2.5798 Pajaro 0 54.621 12.8251

Arkansas 0 82.012 2.8716 Pamlico 0 18.985 1.4050

Atchafalaya 0 16.073 .3291 Pascagoula 0 30.056 2.4426

Biloxi 0 12.781 1.4203 Peace 0 13.165 .3133

Black 0 13.755 .4348 Pearl 0 29.891 1.3236

Brazos 0 39.087 1.5709 Pee Dee 0 51.816 2.9126

Calcasieu 0 12.533 .7617 Penobscot 0 67.428 3.4281

Caloosahatchee 0 5.738 .0781 Platte 0 78.849 3.8316

Cape Fear 0 39.303 1.6845 Puget Sound 0 84.655 13.1218

Chehalis 0 65.953 10.3737 Rainy 0 46.885 1.3063

Chesapeake Bay 0 69.301 6.1317 Red 0 56.000 1.9979

Cheyenne 0 60.039 4.3215 Red River 0 53.478 .6381

Choctawhatchee 0 29.008 2.3003 Rio Grande 0 79.878 4.3820

Chowan 0 21.775 1.4813 Roanoke 0 55.101 4.6593

Colorado 0 88.926 8.3710 Rogue 0 68.504 16.7673

Colorado-Texas 0 48.181 1.6211 Sabine 0 28.208 1.6643

Columbia 0 85.397 11.6346 Sacramento/

San Joaquin

0 84.760 9.4769

Connecticut 0 65.914 7.2958 Saint John 0 76.402 3.4405

Delaware 0 66.791 4.4139 Saint Johns 0 20.819 .4986

Edisto 0 16.575 .9905 Salinas 0 64.031 12.0949

Eel 0 65.226 17.7757 San Francisco 0 53.465 9.9823

Escambia 0 28.151 2.6659 San Gabriel 0 66.466 11.3324

The Everglades 0 12.432 .1044 Santa Maria 0 63.399 15.6017

Great Basin 0 85.113 7.2859 Santa Ynez 0 63.553 16.1116

Great Lakes 0 59.533 1.7116 Santee 0 71.043 4.2782

Hudson 0 64.788 6.6372 Satilla 0 12.781 .6199

Kansas 0 33.065 2.0485 Savannah 0 71.033 3.4455

Kennebec 0 70.301 5.5723 Souris 0 49.881 .6561

Klamath 0 74.085 12.4504 Suwannee 0 19.328 .6775

Lake Champlain 0 67.814 6.7859 Tampa Bay 0 12.005 .3874

Merrimack 0 60.644 5.5055 Trinity 0 29.430 1.3535

Mississippi 0 85.539 3.8619 Umpqua 0 68.545 18.0453

Missouri 0 81.309 4.0302 Waccamaw 0 11.697 .3336

Mobile 0 54.426 4.0093 Withlacoochee 0 15.294 .5734

Navidad 0 12.464 .5591 Yellow 0 18.128 1.8890

Neuse 0 22.512 1.1622 Yellowstone 0 81.309 7.6615

Nueces 0 58.237 1.8513

Ochlockonee 0 24.734 1.5247

Ogeechee 0 22.280 1.2536

14 Elevation-Derived Watershed Basins and Characteristics for Major Rivers of the Conterminous United States
Table 10. National Inventory of Dams (NID) “Purposes” attribute 

categories.

“Purposes”

Attribute “Purposes” Attribute Categories

C Flood Control and Storm Water Management

D Debris Control

F Fish and Wildlife Pond

H Hydroelectric 

I Irrigation

N Navigation

P Fire Protection/Stock or Small Farm Pond

R Recreation

S Water Supply

T Tailings

Results 15

Atlas, the NLCD Retrofit Land Cover Change Data were 

released (http://www.mrlc.gov/multizone.php). Had these data 

been available during this research, they would have been 

included in the summarized statistics because they provide a 

more direct comparison with the 1992 NLCD (U.S. Geological Survey, 2007) categories.

Conclusions

Elevation-derived watersheds and characteristics for 

major rivers in the United States are developed to quantify 

EDNA hydrologic footprint characteristics so that researchers 

can evaluate the health of the Nation’s watersheds by analyzing biological, physical, and anthropogenic change within 

watersheds. The watersheds are derived from the EDNA 

database by using the watershed generation tool to delineate 

watershed basins, or contributing areas, upstream from the 

mouth of major rivers of the conterminous United States. 

Watershed characteristics are selected to provide metrics for 

land cover distribution, population, drainage area, elevation, 

slope, and other ancillary data such as dams. The compilation 

of watershed basins and their characteristics are documented 

in an EDNA Watershed Atlas at http://edna.usgs.gov/

watersheds/.

The EDNA Watershed Atlas is a valuable resource for 

analyzing watershed characteristics and evaluating change 

within major river basins of the conterminous United States. 

This new database is broadly useful in landscape change 

modeling and subsequent monitoring activities in future years.

References Cited

Deichmann, U., Balk, D., and Yetman, G., 2001, Transforming 

population data for interdisciplinary usages from census to 

grid: The World Bank, 19 p. (Also available online at http://

sedac.ciesin.columbia.edu/gpw-v2/GPWdocumentation.pdf)

Franken, S.K., Tyler, D.J., and Verdin, K.L., 2001, Development of a national seamless database of topography and 

hydrologic derivatives, Proceedings of the 21st ESRI User’s 

Conference, July 9–13, 2001, San Diego, CD–ROM. (Also 

available online at http://gis.esri.com/library/userconf/

proc01/professional/papers/pap730/p730.htm)

Gesch, D., Oimoen, M., Greenlee, S., Nelson, C., Steuck, M., 

and Tyler, D., 2002, The National Elevation Dataset: Photogrammetric Engineering and Remote Sensing, v. 68, no. 1, 

p. 5–33. (Also available online at http://www.asprs.org/

publications/pers/2002journal/january/highlight.html)

Gridded Population of the World, Version 3 (GPWv3), 2005, 

Gridded population of the world, version 3 (GPWv3) data 

collection: Center for International Earth Science Information Network (CIESIN), Centro Internacional de Agricultura Tropical (CIAT), July 2006, available online at 

http://sedac.ciesin.columbia.edu/gpw/index.jsp

Kost, J.R., and Kelly, G.G., 2001, Watershed delineation 

using the National Elevation Dataset and semiautomated 

techniques. Proceedings of the 21st ESRI User’s Conference, July 9–13, 2001, San Diego, CD–ROM. (Also available online at http://gis.esri.com/library/userconf/proc01/

professional/papers/pap421/p421.htm)

U.S. Geological Survey, 2007, Multi-Resolution Land Characteristics (MRLC) Consortium, National Land Cover 

Database, available online at http://www.mrlc.gov

Verdin, K.L., and Greenlee, S.K., 2003, Continuous parameterization using EDNA, Proceedings of the 23rd ESRI 

User’s Conference, July 7–11, 2003, San Diego, CD–ROM. 

(Also available online at http://gis.esri.com/library/

userconf/proc03/p0617.pdf)
Figure 4. EDNA Watershed Atlas Web portal (http://edna.usgs.gov/watersheds) is accessible in a standard Web browser (HTML link) 

or with a three-dimension option, such as Google Earth (KML version link). 

16 Elevation-Derived Watershed Basins and Characteristics for Major Rivers of the Conterminous United States
Figure 5. The EDNA Watershed Atlas is accessible from the EDNA Web site at http://edna.usgs.gov.

Results 17
Figure 6. Land cover characteristics for the Chesapeake Bay watershed (U.S. Geological Survey, 2007).

18 Elevation-Derived Watershed Basins and Characteristics for Major Rivers of the Conterminous United States
Figure 7. Slope characteristics for the Chesapeake Bay watershed (EDNA).

Results 19
Figure 8. Population characteristics for the Chesapeake Bay watershed (Gridded Population of the World, Version 3, 2005).

20 Elevation-Derived Watershed Basins and Characteristics for Major Rivers of the Conterminous United States
Figure 9. Characteristics for the Chesapeake Bay watershed accessible in Google Earth.

Results 21
Figure 10. Land cover characteristics for the Chesapeake Bay watershed, 1992 (U.S. Geological Survey, 2007).

22 Elevation-Derived Watershed Basins and Characteristics for Major Rivers of the Conterminous United States
Figure 11. Land cover characteristics for the Chesapeake Bay watershed, 2001 (U.S. Geological Survey, 2007).

Results 23
Figure 12. Population characteristics for the Chesapeake Bay watershed, 1990 (Gridded Population of the World, Version 3, 2005).

24 Elevation-Derived Watershed Basins and Characteristics for Major Rivers of the Conterminous United States
Figure 13. Population characteristics for the Chesapeake Bay watershed, 2000 (Gridded Population of the World, Version 3, 2005).

Results 25
Figure 14. Elevation characteristics for the Chesapeake Bay watershed (EDNA).

26 Elevation-Derived Watershed Basins and Characteristics for Major Rivers of the Conterminous United States
Figure 15. Slope characteristics for the Chesapeake Bay watershed (EDNA).

Results 27

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For more information concerning this publication, contact:

U.S. Geological Survey

Center for Earth Resources Observation and Science (EROS)

47914 252nd Street

Sioux Falls, SD 57198–0001

(800) 252–4547

Or visit the Earth Resources Observation and Science Center Web site at: 

http://eros.usgs.gov/
Poppenga and Worstell—Elevation-Derived Watershed Basins and Characteristics for Major Rivers of the Conterminous United States—SIR 2008–5153