Streambed Adjustment and Channel 

Widening in Eastern Nebraska

By David L. Rus, Benjamin J. Dietsch, U.S. Geological Survey, and 

Andrew Simon, National Sedimentation Laboratory

U.S. GEOLOGICAL SURVEY

Water-Resources Investigations Report 03-4003

Prepared in cooperation with the

NEBRASKA DEPARTMENT OF ROADS,

NEBRASKA DEPARTMENT OF NATURAL RESOURCES,

LOWER PLATTE SOUTH NATURAL RESOURCES DISTRICT,

PAPIO-MISSOURI RIVER NATURAL RESOURCES DISTRICT,

U.S. ARMY CORPS OF ENGINEERS, and the 

NATIONAL SEDIMENTATION LABORATORY OF THE U.S. 

DEPARTMENT OF AGRICULTURE

Lincoln, Nebraska

2003
District Chief

U.S. Geological Survey

Box 25046, Mail Stop 415

Denver Federal Center

Denver, CO 80225–0046

For additional information write to:

District Chief

U.S. Geological Survey

406 Federal Building

100 Centennial Mall North

Lincoln, NE 68508

http://www.usgs.gov/

U.S. DEPARTMENT OF THE INTERIOR

GALE A. NORTON, Secretary

U.S. GEOLOGICAL SURVEY

Charles G. Groat, Director

The use of firm, trade, and brand names in this report is for identification purposes only and does 

not constitute endorsement by the U.S. Geological Survey.

Copies of this report can be purchased 

from:

U.S. Geological Survey

Information Services

Box 25286

Denver Federal Center

Denver, CO 80225
CONTENTS iii

CONTENTS

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

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

Purpose and Scope....................................................................................................................................................... 2

Description of Study Area ........................................................................................................................................... 2

Attributes Associated with Channel Adjustment in Eastern Nebraska ....................................................................... 5

Acknowledgments ....................................................................................................................................................... 6

Methods ................................................................................................................................................................................. 6

Site Selection ............................................................................................................................................................... 6

Data Collection ............................................................................................................................................................ 6

Topographic Data............................................................................................................................................... 13

First-Round Survey.................................................................................................................................. 13

Second-Round Survey ............................................................................................................................. 13

Reference to National Geodetic Vertical Datum of 1929 ........................................................................ 13

Streambed Particle-Size Analyses ............................................................................................................................... 14

Characterization of Streambed Adjustment................................................................................................................. 14

Streambed Elevation History ............................................................................................................................. 14

Influences on the Streambed.............................................................................................................................. 17

Disturbances ............................................................................................................................................ 17

Knickpoints.............................................................................................................................................. 17

Grade-Control Structures......................................................................................................................... 18

Characterization of Recent Channel Widening............................................................................................................ 18

Contouring First-Round Survey Data................................................................................................................ 18

Overlay of Second-Round Survey Data ............................................................................................................ 18

Characterization of Individual Top-of-Bank Failures........................................................................................ 18

Computation of Widening Rates........................................................................................................................ 18

Streambed Adjustment........................................................................................................................................................... 19

Potential Study-Area-Wide Disturbances .................................................................................................................... 20

Changes to the Median Water-Surface Elevation of the Missouri River........................................................... 20

Agricultural Development in Nebraska ............................................................................................................. 20

Missouri River Tributary Basins.................................................................................................................................. 20

Documented Disturbances, Knickpoints, and Grade-Control Structures .......................................................... 20

Streambed Summaries ....................................................................................................................................... 22

Papillion Creek Basin .................................................................................................................................................. 23

Documented Disturbances, Knickpoints, and Grade-Control Structures .......................................................... 25

Original Straightening.............................................................................................................................. 25

Urbanization ............................................................................................................................................ 26

Flood-Control Channel Modifications Since the 1960s .......................................................................... 27

Degradation of the Missouri River .......................................................................................................... 27

Streambed Summaries ....................................................................................................................................... 27

Platte River Tributary Basins....................................................................................................................................... 29

Documented Disturbances, Knickpoints, and Grade-Control Structures .......................................................... 29

Straightening in the Platte River Flood Plain .......................................................................................... 29

Basinwide Straightening.......................................................................................................................... 29

Straightening at PRT-3............................................................................................................................. 29

Streambed Summaries ....................................................................................................................................... 31

Elkhorn River Basin .................................................................................................................................................... 32

Documented Disturbances, Knickpoints, and Grade-Control Structures .......................................................... 34

Straightening of the Elkhorn River.......................................................................................................... 34

Straightening of Logan Creek.................................................................................................................. 34

Straightening of Maple Creek.................................................................................................................. 35

Straightening of Other Elkhorn River Tributaries ................................................................................... 35

CONTENTS
iv CONTENTS

Streambed Summaries ....................................................................................................................................... 35

Salt Creek Basin .......................................................................................................................................................... 37

Documented Disturbances, Knickpoints, and Grade-Control Structures .......................................................... 37

Original Channelization of Salt Creek .................................................................................................... 37

Individual Tributary Modifications ......................................................................................................... 39

Urbanization and Flood Control Modifications in the Lincoln Area ...................................................... 40

Streambed Summaries ....................................................................................................................................... 41

Little Nemaha River Basin .......................................................................................................................................... 44

Documented Disturbances, Knickpoints, and Grade-Control Structures .......................................................... 44

Original Straightening ............................................................................................................................. 44

Channelization in the South Fork Little Nemaha River and Muddy Creek Subbasins ........................... 44

Streambed Summaries ....................................................................................................................................... 46

Big Nemaha River Basin ............................................................................................................................................. 48

Documented Disturbances, Knickpoints, and Grade-Control Structures .......................................................... 48

Streambed Summaries ....................................................................................................................................... 48

Big Blue River Basin................................................................................................................................................... 51

Documented Disturbances, Knickpoints, and Grade-Control Structures .......................................................... 51

Streambed Summaries ....................................................................................................................................... 51

Channel Widening ................................................................................................................................................................. 54

Summary and Conclusions .................................................................................................................................................... 60

References ............................................................................................................................................................................. 60

FIGURES

1–3. Maps showing:

1. Location of study area, river basins, and sampling sites, Nebraska and Kansas .............................................. 3

2. Generalized classification of soil parent materials showing study area and river basins, Nebraska ................ 4

3. Location of loess area of Midwestern United States and thickness of loess..................................................... 5

4. Diagrams showing characterization of top-of-bank widening between first and second rounds of 

surveying by: (A) Identifying individual failures along the top-of-bank, and (B) characterizing the 

geometry of each....................................................................................................................................................... 19

5. Graph showing total area of harvested crops in Nebraska, 1866–1990.................................................................... 20

6. Map showing location of Missouri River Tributary Basins and associated study sites in Nebraska........................ 21

7. Graph showing streambed-elevation changes at Elk Creek at US20 (MRT-8)......................................................... 22

8. Map showing location of the Papillion Creek Basin and associated study sites in Nebraska .................................. 24

9. Photographs looking upstream at W Papillion Cr at US275 (PC-3)......................................................................... 26

10. Graph showing streambed-elevation changes at W Papillion Cr at 66th Street (PC-H)........................................... 26

11. Graph showing streambed-elevation changes at Wehrspann Cr at N370 (PC-F)..................................................... 27

12. Photograph showing channel and levee construction, Big Papillion Creek ............................................................. 27

13. Graph showing streambed-elevation changes at Big Papillion Cr at Cornhusker Rd (PC-M)................................. 29

14. Map showing location of Platte River Tributary Basins and associated study sites in Nebraska............................. 30

15. Graph showing streambed-elevation changes at Skull Creek at Butler County road (PRT-5) ................................. 31

16. Photograph looking downstream at grade-control structure on Skull Creek at PRT-5 ............................................. 31

17. Graph showing streambed-elevation changes at Otoe Cr at US77 (PRT-7) ............................................................. 32

18. Map showing eastern part of the Elkhorn River Basin and associated study sites in Nebraska............................... 33

19. Photograph showing drop structure at S Logan Cr at N15 (ER-12) ......................................................................... 35

20. Photograph showing knickpoint on East Fork Maple Creek located at SW1/4 sec. 26, T. 19 N., R. 4 E. ............... 35

21. Graph showing streambed-elevation changes at Logan Cr at Dodge County Road 22 (ER-15).............................. 37

22. Map showing location of Salt Creek Basin and associated study sites in Nebraska ................................................ 38

23. Graph showing streambed-elevation changes at Salt Cr at N 27th St, Lincoln (SC-13) .......................................... 39

24. Graph showing stream channel response at Middle Cr at US6 (SC-7) following 1917 straightening ..................... 39

25. Photograph of knickpoint and graph showing streambed profile observed at Sand Cr Tributary at 

Saunders County Road 24 (SC-31)........................................................................................................................... 40

26. Photograph showing grade-control structure on Beal Slough upstream from Link 55W (SC-H)............................ 41

27. Graph showing streambed-elevation changes at Little Salt Cr at Arbor Road (SC-21) ........................................... 41
CONTENTS v

28. Map showing location of the Little Nemaha River Basin and associated study sites in Nebraska .......................... 45

29. Photograph showing channel incision observed in 1998 on Spring Creek about 3.5 kilometers upstream

from LNR-11 ............................................................................................................................................................ 46

30. Graph showing streambed-elevation changes at S Fk Little Nemaha River at N50 (LNR-8) ................................. 46

31. Map showing location of the Big Nemaha River Basin and associated study sites in Nebraska............................. 49

32. Graph showing streambed-elevation changes at N Fk Big Nemaha R at N105 (BNR-9)........................................ 51

33. Map showing location of the Big Blue River Basin and associated study sites in Nebraska................................... 52

34. Photograph showing grade-control structure on Big Indian Creek between Gage County Road (BBR-11) 

and US77 (BBR-12) ................................................................................................................................................. 53

TABLES

1. Primary study sites for documentation of streambed adjustment and channel widening in eastern 

Nebraska, 1996 to 1999 .......................................................................................................................................... 7

2. Supplemental study sites for documentation of streambed adjustment in eastern Nebraska ................................. 11

3. Sources and types of historical streambed-elevation data ...................................................................................... 15

4. Methods for referencing data sets with the National Geodetic Vertical Datum of 1929 ........................................ 16

5. Drainage districts associated with Missouri River Tributary Basins...................................................................... 22

6. Streambed summaries for sites in the Missouri River Tributary Basins................................................................. 23

7. Drainage districts of the Papillion Creek Basin...................................................................................................... 25

8. Streambed summaries for sites in the Papillion Creek Basin ................................................................................. 28

9. Drainage districts associated with selected Platte River tributaries ....................................................................... 31

10. Streambed summaries for sites in the Platte River Tributary Basins...................................................................... 32

11. Drainage districts associated with the Elkhorn River Basin................................................................................... 34

12. Streambed summaries for sites in the Elkhorn River Basin ................................................................................... 36

13. Streambed summaries for sites in the Salt Creek Basin ......................................................................................... 42

14. Drainage districts associated with the Little Nemaha River Basin......................................................................... 46

15. Streambed summaries for sites in the Little Nemaha River Basin ......................................................................... 47

16. Drainage districts associated with the Big Nemaha River Basin............................................................................ 48

17. Streambed summaries for sites in the Big Nemaha River Basin ............................................................................ 50

18. Streambed summaries for sites in the Big Blue River Basin.................................................................................. 53

19. Individual top-of-bank failure dimensions ............................................................................................................. 54

20. Summary of observed channel widening................................................................................................................ 57

CD–ROM (in pocket)

Compilation of streambed elevation data for study sites related to streambed adjustment and channel 

widening in eastern Nebraska
vi CONTENTS

CONVERSION FACTORS AND ABBREVIATIONS

Multiply By To obtain

centimeter (cm) 0.394 inch (in)

 meter (m) 3.28 foot (ft)

kilometer (km) 0.622 mile (mi)

meters per meter (m/m) 1 feet per foot (ft/ft)

square meter (m2) 10.8 square foot (ft2)

hectare (ha) 2.47 acre (ac)

square kilometer (km2) 0.386 square mile (mi2)

cubic meter (m3) 35.3 cubic foot (ft3)

meter per year (m/yr) 3.28 foot per year (ft/yr)

cubic meter per second (m3/s) 35.3 cubic foot per second (ft3/s)

Elevation, as used in this report, refers to distance above the National Geodetic Vertical Datum of 1929 (NGVD29).

Unless otherwise noted, photographs presented in this report were taken by employees of the U.S. Geological Survey.
Abstract 2

Streambed Adjustment and Channel Widening in 

Eastern Nebraska

By David L. Rus, Benjamin J. Dietsch, and Andrew Simon

Abstract

In eastern Nebraska, stream straightening 

and dredging efforts since the 1890s have 

disturbed the natural equilibrium of stream channels and have led to streambed adjustment by 

degradation and subsequent channel widening. 

This report describes a study to evaluate the effect 

these disturbances have had on stream channels in 

eastern Nebraska. 

Two sets of survey data were collected 

approximately 2 years apart during 1996–99 at 

151 primary sites. Additionally, historical 

streambed-elevation data (dating back to the 

1890s) were compiled from several sources for 

the primary sites and 45 supplemental sites, and 

relevant disturbances were identified for each of 

eight basin groupings. Streambed-elevation data 

sets were used to estimate the amount of change 

to the streambed at the sites over the time period 

of the data. Recent channel widening was documented for 73 of the primary sites by comparing 

the two survey sets.

The majority of observed streambedgradation responses appear to be related to the 

various straightening efforts and to the effects of 

grade-control structures in the study area. 

Channel responses were complicated by the presence of multiple disturbances. However, in many 

cases, the streambed-elevation data sets provide a 

reliable representation of the past streambed 

gradation, with some sites showing 6 to 7 meters 

of degradation since they were straightened. 

Many sites that had been straightened showed 

considerable degradation following the disturbance. This indicates that eastern Nebraska 

stream channels can regain equilibrium mainly 

through the slope adjustment process of headward-progressing degradation.

Bank failures were documented at sites in 

all eight of the basin groupings analyzed, and 

widening rates were computed at 64 of 73 sites. 

Observed bank widening in the Big Blue River 

Basin, a relatively unstraightened basin, indicates 

that other disturbances besides stream-channel 

straightening may be causing channel responses 

in the basin and possibly in the entire study area.

INTRODUCTION

Many stream channels in the loess area of 

eastern Nebraska have been dredged and straightened 

since the 1890s. This engineering practice reduced 

flooding and increased the agricultural productivity of 

the flood plain at the time. However, channel gradient 

and the ability of the flow to erode channel sediments 

also increased. As a result, the long-term effect on the 

modified channels and adjacent tributaries of eastern 

Nebraska has been headward-progressing degradation, 

which has heightened and steepened channel banks, 

causing channel widening by bank failures. These 

channel responses affect the design and maintenance 

of structures crossing the channels and can have 

adverse effects on riparian health. In eastern Nebraska, 

many bridges already weakened by channel incision 

required closure following flooding that occurred in 

1993. Streambed degradation caused by straightening 

also is believed to have accelerated the drainage of 

saline wetlands along Little Salt Creek (Farrar and 

Gersib, 1991) and Rock Creek (Natural Resources 

Conservation Service, 1996a).
INTRODUCTION 3

Purpose and Scope

To better understand the channel responses in 

eastern Nebraska, the U.S. Geological Survey 

(USGS), in cooperation with the Nebraska Department 

of Roads, Nebraska Natural Resources Commission 

(now part of the Nebraska Department of Natural 

Resources), Lower Platte South Natural Resources 

District (NRD), Papio-Missouri River NRD, U.S. 

Army Corps of Engineers (USACE), and the U.S. 

Department of Agriculture, Agricultural Research 

Service (ARS), National Sedimentation Laboratory 

(NSL), did a study from 1995 to 2000 to characterize 

the stability of stream channels in eastern Nebraska. 

As part of the study, this report documents streambed 

adjustment and channel responses in eastern Nebraska 

with compiled data sets of streambed elevation over 

time at 196 sites and recent channel widening at 73 of 

the sites. 

Besides the work presented here, the study 

consisted of several other components. A database was 

created from the assessment of nearly 1,000 bridges 

for potential scour-critical conditions (U.S. Army 

Corps of Engineers, 1999). Aerial reconnaissance was 

used to estimate the stage of channel evolution using 

techniques described by Simon (1989) for most channels in the study area (U.S. Army Corps of Engineers, 

1995; 1998). Trends in water-surface elevation for a 

given discharge were examined at 145 stream-gaging 

stations in Nebraska (Chen and others, 1999). 

Channel-bank stability analyses were performed at 

approximately 150 sites. Channel evolution models 

were developed for two streams in the study area 

(North Branch West Papillion Creek and Little Salt 

Creek) to assess the effects of mitigation measures and 

urbanization (Langendoen and Simon, 2000).

Description of Study Area 

The study area includes sites from 28 counties 

in eastern Nebraska and parts of three adjacent counties in Kansas (fig. 1). The study area lies in the 

Dissected Till Plains of the Central Lowland physiographic province (fig. 2) (Fenneman, 1946). This part 

of Nebraska is a glaciated region characterized by 

rolling hills, covered by easily erodible soil. With the 

exception of the Elkhorn River Basin where coarsegrained sediments are present in the western uplands, 

unconsolidated sediments derived from loess deposits 

of Pleistocene age dominate the surficial geology in 

the uplands of this region (fig. 2) (Elder, 1969). Areas 

of the region capped with loess contain some of the 

thickest loess deposits in the Midwestern United States 

(fig. 3). Glacial till composed of poorly sorted materials lies beneath the loess mantle throughout much of 

the region and is exposed on lower slopes in some 

areas. Bedrock occurs in parts of the region, especially 

in southeastern Nebraska, but most streambeds lack 

bedrock control. 

The study area (fig. 1) is included in parts of 

four major land-resource areas (MLRAs) (Soil 

Conservation Service, 1981). The Iowa and Missouri 

Loess Hills (MLRA 107) area has rolling to hilly 

topography that is highly dissected; the erosion hazard 

from runoff is severe on the uplands. The Loess 

Uplands and Till Plains (MLRA 102B) have welldefined drainages in the uplands although the till 

plains are level to gently rolling with less defined 

drainages. The Nebraska and Kansas Loess–Drift Hills 

(MLRA 106) have steep and strongly sloping areas 

generally consisting of glacial till, and the areas with 

flatter slopes consist of loess. The remaining part of 

the study area lies in the Central Loess Plains (MLRA 

75). In the study area, these plains are gently rolling 

and mantled by loess. 

All basins in the study area are part of the 

Missouri River Basin. Study sites were grouped 

according to stream basin. Six major stream basins 

were identified in the study area: Papillion Creek, 

Elkhorn River, Salt Creek, Little and Big Nemaha 

River, and Big Blue River Basins (fig. 1). Sites not 

located within one of the major stream basins were 

grouped into Missouri River tributary basins or Platte 

River tributary basins. The Missouri River tributary 

basins are Bow Creek, Aowa Creek, Elk Creek, 

Omaha Creek, Elm Creek, New York Creek, Weeping 

Water Creek, and Honey Creek Basins (fig. 6, later in 

report). The Platte River tributary basins include Shell 

Creek, Bone Creek, Skull Creek, Otoe Creek, Buffalo 

Creek, Springfield Creek, and Fourmile Creek Basins 

(fig. 14, later in report). 

Alluvial soil types vary within the region but 

generally consist of silt, silt loam, and silty-clay loam 

(Nebraska Soil and Water Conservation Commission, 

1968; Soil Conservation Service, 1975). In the 

Elkhorn River Basin, western streambanks are sandy 

materials whereas streambanks in the eastern part of 

the basin are silty loess (Soil Conservation Service, 

1971). The alluvial stratigraphy of the fine-grained 

deposits found in eastern Nebraska stream valleys are 

similar to those found in the DeForest Formation of 

western Iowa (Mandel and Bettis, 1995). 
INTRODUCTION 4

Figure 1. Location of study area, river basins, and sampling sites, Nebraska and Kansas.

97 ̊

42 ̊

96 ̊

41 ̊

40 ̊

Study sites

Surface water

Big Blue River Basin

Big Nemaha River Basin

Nebraska and Kansas counties

Study area Elkhorn River Basin

Little Nemaha River Basin

Selected Missouri River tributary basins

Selected Platte River tributary basins

Papillion Creek Basin

Salt Creek Basin

EXPLANATION

Nema Brown

Marshall

Jefferson

Saline

Lancaster

Johnson

Pawnee

Richardson

Nemaha

Otoe

Cass

Sarpy

Saunders

Douglas

Washington

Burt

Cuming

Stanton

Colfax Dodge

Polk Butler

Seward

Platte

Madison

Pierce

Wayne

Cedar

Knox

Dixon

Dakota

Thurston

Gage

v a e h

L

m i ittle N a e r R

Bi i g

R B e lu ve r

e ek

S alt Cr

r i

 

h E or R ve

lk n

Big Nemaha River

Papillion Creek

Platte Rive r

Missouri River

Location map

South Dakota

Nebraska

Kansas

Iowa

Colorado Missouri Wyoming

Major Land Resource Areas (MLRA)

 (Soil Conservation Service, 1981)

102B

107

106

Central 

loess plains

Loess uplands 

and till plains

Iowa and Missouri 

loess hills

Nebraska

and Kansas

loess drift hills

75

0 10 20

0 10 30 20 KILOMETERS

30 MILES

Base from U. S. Geological Survey

1:100,000 digital data

Albers Equal-Area Conic projection

Standard parallels 29 ̊30' and 45 ̊30'

Central meridian -96 ̊00'
5 Streambed Adjustment and Channel Widening in Eastern Nebraska 104 ̊ 98 ̊ 41 ̊ 42 ̊

EXPLANATION

SAND AND SILT

SAND

ALLUVIUM

LOESS

LOESS AND DRIFT

LOESS AND ALLUVIUM

SHALE

SANDSTONE

SCALE IN MILES

20 0 20 40 60

BASIN BOUNDARIES

S

Great Plain

Mis

u

P

0 40 MILES 20

0 20 40 KILOMETERS

Base from U.S. Geological Survey1:100,000 digital dataAlbers Equal-Area Conic projectionStandard parallels 29 ̊30' and 45 ̊30'

central meridian -96 ̊00

Figure 2. Generalized classification of soil parent materials showing study area and river basins, Nebraska.
INTRODUCTION 6

Attributes Associated with Channel 

Adjustment in Eastern Nebraska

In general, stream-channel adjustment processes 

can be characterized by the interaction between 

(1) bed material load, (2) streamflow discharge, 

(3) channel slope, and (4) channel geometry (Mackin, 

1948). A stream system where these attributes balance 

each other out is considered to be in equilibrium. 

However, changes can be imposed on the system that 

alter one or more of these attributes and can lead to 

indirect changes in the others, as the stream attempts 

to return to an equilibrium state through the processes 

of erosion and sediment transport. The imposed 

changes are referred to in this report as disturbances, 

and the indirect changes are the channel response. As 

used in this report, aggrading or degrading responses 

reflect upward or downward changes, respectively, in 

streambed elevation. According to this framework, 

stream-channel straightening in the loess areas of 

eastern Nebraska disturbed the equilibrium by 

increasing the channel slope. The channel then 

responded accordingly through changes in one or 

more of the attributes. 

The bed material load is considered unchanged 

for streams located over loess-derived alluvial deposits 

because a negligible supply of coarse-sized sediment 

particles is available. The bed material load consists of 

particles too massive to be continuously entrained by 

the stream, such as sand or gravel. Entrained particles 

with low settling velocities, such as silts and clays, 

require very little energy to remain suspended. Once 

suspended, these materials do not play a significant 

role in the adjustment process. The sediment supplied 

from alluvial loess deposits in eastern Nebraska is 

mainly composed of fine-textured materials such as 

silt, with only small amounts of coarse sediment. 

However, coarse sediments could still become available through the cumulative effect of many years of 

stream-channel erosion or the result of layers of sand 

and gravel being exposed. Channels that cut through 

the loess cap and entrain the coarser sand and gravel 

deposits below have a supply of coarse material that 

increases bed material loads that are deposited in 

downstream reaches, causing aggradation. Severe 

channel incision into the thick loess cap would have to 

occur before these coarse materials would become 

available for downstream deposition. 

Because streamflow discharge is independent of 

the other channel attributes, it could also be considered 

unchanged. As a result, stream channels in eastern 

Nebraska that have had their channel slopes increased 

are correcting to a new equilibrium by reducing the 

channel slope and increasing the width and depth of 

the channel. As long as no coarse sediments are 

present for downstream aggradation, channel-slope 

adjustment is limited to lateral channel migration or 

headward-progressing streambed degradation.

Headward-progressing streambed degradation 

occurs through the formation of knickpoints, which are 

locally steep channel reaches located in erodible 

streambed material (Tim Diehl, U.S. Geological 

Survey, written commun., 2002). Stream velocity 

increases as water flows over the sudden drop in 

streambed elevation, which cannot be sustained by 

cohesive streambeds such as silt and clay. As a result, 

knickpoints migrate upstream and will theoretically 

continue to do so until a drainage divide is reached or 

streambed material (whether natural or artificial) is 

encountered that can sustain the elevation drop 

(Schumm and others, 1984). 

South Dakota

North Dakota

Nebraska

Kansas

Oklahoma

Texas

Arkansas

Louisiana

Missouri

Iowa

Alabama

Mississippi

Tennessee

Kentucky

Illinois Indiana Ohio

Georgia

Minnesota

Michigan

Wisconsin

43 ̊

37 ̊

97 ̊ 89 ̊

0 200 MILES 100

0 100 200 KILOMETERS

Figure 3. Location of loess area of Midwestern United States 

and thickness of loess, in feet (modified from Luttenegger, 

1987).
7 Streambed Adjustment and Channel Widening in Eastern Nebraska

Streambed degradation leads to increased bank 

heights and oversteepened bank angles. The channel 

geometry is adjusted through bank failures, which 

continue until the bank becomes stable. The cumulative effect of these failures is a widened channel, 

which can pose a threat to existing bridges that span 

the channel and results in the loss of land adjacent to 

the channel. 

Acknowledgments

The findings presented in this report are the 

culmination of a cooperative effort among several 

agencies and individuals whose assistance was vital 

and greatly appreciated. The authors thank the landowners for permission to collect geomorphic data on 

their property. The authors also thank representatives 

from each of the cooperating agencies, specifically 

Don Jisa (Nebraska Department of Roads), Randy 

Behm (U.S. Army Corps of Engineers), Dan Schulz 

(Lower Platte South Natural Resources District), 

Marlin Petermann (Papio-Missouri River Natural 

Resources District), Andrea Curini (formerly of the 

National Sedimentation Laboratory), and Jerry Wallin 

(formerly of the Nebraska Natural Resources Commission) for their support and knowledge and for 

providing access to a wealth of historical geomorphic 

data. Thanks also go to colleagues and student interns 

within the USGS who provided assistance in 

collecting and analyzing geomorphic data as well as 

the review of this report. 

METHODS

Streambed adjustment was documented at 

196 sites, which included 151 primary study sites and 

45 supplemental study sites. At the primary sites, field 

activities included at least two topographic surveying 

events as well as streambed particle-size sampling 

during 1996–99. At all 196 sites, historical channel 

geometry data were compiled, and temporal data sets 

of streambed elevation were created. Recent channel 

widening was characterized at 73 of the primary sites.

Site Selection

Primary study sites were distributed among the 

major drainage basins of the study area and were individually selected based on the availability of historical 

streambed-elevation data (table 1). Because the 

majority of historical data were associated with bridge 

crossings, all of the sites were located at bridges. The 

bridges were good landmarks for isolating streambed 

data from several sources into one location and for 

establishing reference points for future comparisons. 

Scour processes, especially those associated 

with bridge crossings, could have introduced variance 

into the data sets of streambed elevation. Contraction 

scour typically occurs during the rising stage of runoff 

events, and then scour holes fill in as the stage falls 

if depositional materials are available (Richardson and 

others, 1993). Few data are available regarding the 

supply of depositional materials during runoff events 

in eastern Nebraska, but it is likely that the process is 

supply-limited in areas dominated by loess, and the 

time required for scour holes to fill in may be considerably longer for silt-bed channels than for sand-bed 

channels. The effects of local scour, which is caused 

by flow obstructions such as bridge piers, were

minimized by compiling and collecting streambedelevation data that were not adjacent to such obstructions. Determining the magnitude of variance in

streambed elevation caused by scour is dependent on 

flow characteristics for each bridge, which is beyond 

the scope of this study. Although this variance was 

likely present in the streambed-elevation data sets, the 

long-term effects of degradation or aggradation of the 

streambed were increasingly recognizable with more 

data points over longer periods of time. 

In addition to the primary sites where field data 

collection was performed, 45 supplemental sites were 

used to document streambed adjustment (table 2). At 

these sites, only historical data were compiled and 

presented, with the exception of tapedown measurements collected at sites along Beal Slough in the Salt 

Creek Basin. 

Data Collection

Topographic stream-channel surveys were 

done at the primary sites for two purposes. The 

surveys provided a recent (between 1996 and 1999)
METHODS 8

Table 1. Primary study sites for documentation of streambed adjustment and channel widening in eastern Nebraska, 

1996 to 1999

[ID, identification; NDOR, Nebraska Department of Roads; No., number; Cr, Creek; N#, Nebraska State route; Nebr, Nebraska; W, west; US#, U.S. route; CR, 

County Road; Co, County; sec, section; T#X, township; N, north; R#X, range; E, east; NW, northwest; SE, southeast; S, south; St, Street; Rd, Road; Br, Branch; 

trib, tributary; L#X, State connecting link; Ave, Avenue; S#X, State spur; R, River M, Middle; Fk, Fork; SW, southwest]

Site ID Station name1 NDOR bridge ID

Missouri River Tributary Basins

MRT-1 Bow Cr at N84 S084 04362

MRT-2 Bow Cr at N12 (Bow Cr at St. James, Nebr 06478518) S012 20744

MRT-3 W Bow Cr at US81 S081 20306

MRT-4 Aowa Cr at CR, Dixon Co (near center sec 1, T30N, R5E) C026 22325P

MRT-5 South Cr at CR, Dakota Co (NW1/4 sec 10, T29N, R5E) C026 13020

MRT-6 Aowa Cr at N12 S012 23427

MRT-7 Otter Cr at CR, Dixon Co (SE1/4 sec33, T29N, R6E) C026 13810P

MRT-8 Elk Cr at US20 S020 42270

MRT-9 S Omaha Cr at N94 (S Omaha Cr at Walthill, Nebr 06600900) S094 01301

MRT-10 Omaha Cr at Main St, Homer (Omaha Cr at Homer, Nebr 06601000) C022 23015

MRT-11 Elm Cr at US75 S075 14855

MRT-12a New York Cr at New York Cr Rd, Washington Co (New York Cr east of Spiker, Nebr 06608900) C089 21910P

MRT-12b New York Cr at CR21, Washington Co

MRT-13 Weeping Water Cr at N1 S001 00266

MRT-14 Weeping Water Cr at CR, Cass Co (Weeping Water Cr at Weeping Water, Nebr 06806460) C013 13710P

MRT-15 S Br Weeping Water Cr at N67 S067 06587

MRT-16 Weeping Water Cr at US75 (Weeping Water Cr at Union, Nebr 06806500) S075 05774

MRT-17 Honey Cr at N67 S067 02402

Papillion Creek Basin

PC-1 N Br W Papillion Cr at Fort St, Douglas Co C028 21415

PC-2 N Br W Papillion Cr at Blondo St, Douglas Co C028 21820

PC-3 W Papillion Cr at US275 S275 17757

PC-4 S Papillion Cr trib at Cornhusker Rd, Sarpy Co C077 20620

PC-5 W Papillion Cr at Giles Rd, Sarpy Co C077 20435

PC-6 Big Papillion Cr at 168th St, Douglas Co C028 13140

PC-7 Big Papillion Cr at Fort St, Omaha C028 21420

PC-8 Eagle Run at 120th St, Omaha C028 13910

PC-9 Little Papillion Cr at L28K SL28K 01578

PC-10 Cole Cr at Ames Ave, Omaha C028 F1405

PC-11 Cole Cr at Blondo St, Omaha C028 31835

PC-12 Papillion Cr at Capeheart Rd, Bellevue C077 01205P

Platte River Tributary Basins

PRT-1 Shell Cr at CR, Platte Co (SW1/4 sec 14, T18N, R1E) (Shell Cr near Columbus, Nebr 06795500) C071 05705P

PRT-2 Shell Cr at US30 S030 39774

PRT-3 Bone Cr at S12B SS12B 00427

PRT-4 Bone Cr at N15 S015 09916

PRT-5 Skull Cr at CR, Butler Co (sec 22/27, T16N, R4E) C012 32035

PRT-6 Skull Cr at S12A SS12A 00554

PRT-7 Otoe Cr at US77 S077 10726

PRT-8 Otoe Cr at S78J SS78J 00074

PRT-9 Buffalo Cr trib at 192nd St, Sarpy Co C077 11310

PRT-10 Buffalo Cr at N50 S050 07970
9 Streambed Adjustment and Channel Widening in Eastern Nebraska

Platte River Tributary Basins—Continued

PRT-11 Springfield Cr at Platteview Rd, Sarpy Co C077 11640

PRT-12 Fourmile Cr at N66 S066 10234

PRT-13 Fourmile Cr at Bay Rd, Cass Co C013 00415

Elkhorn River Basin

ER-1 Elkhorn R at US81 (Elkhorn R at Norfolk, Nebr 06799000) S081 15491

ER-2 Union Cr at Main St (old US81), Madison (Union Cr at Madison, Nebr 06799230) C059 H3905

ER-3 Union Cr at CR, Stanton Co (SE1/4 sec 15, T22N, R1E) C084 13205

ER-4 Plum Cr at N15 S015 15738

ER-5 Plum Cr at N51 S051 00598

ER-6 Elkhorn R at N32 (Elkhorn R at West Point, Nebr 06799350) S032 07316

ER-7 Pebble Cr at N32 S032 06215

ER-8 Pebble Cr at N91 S091 19072

ER-9 Pebble Cr at CR "G", Dodge Co (Pebble Cr at Scribner, Nebr 06799385) C027 02305P

ER-10 M Logan Cr at N57 S057 05119

ER-11 Deer Cr at N57 S057 04075

ER-12 S Logan Cr at N15 S015 16384

ER-13 Logan Cr at N35 S035 04053

ER-14 Logan Cr at N94 (Logan Cr at Pender, Nebr 06799450) S094 00025

ER-15 Logan Cr at CR 22, Dodge Co (Logan Cr near Uehling, Nebr 06799500) C027 30645

ER-16 W Fk Maple Cr at N91 S091 17273

ER-17 Dry Cr at N15 S015 11596

ER-18 E Fk Maple Cr at N91 S091 17846

ER-19 Maple Cr at N79 S079 05122

ER-20 Maple Cr at CR20, Dodge Co (Maple Cr near Nickerson, Nebr 06800000) C027 13910

ER-21 Maple Cr at US77 (former site of Maple Cr near Nickerson, Nebr 06800000) S077 12173

ER-22 Bell Cr at N32 S032 09289

ER-23 Little Bell Cr at CR P11, Washington Co C089 01130

ER-24 Bell Cr at CR 26, Washington Co C089 02610

ER-25 Elkhorn R at N64 (Elkhorn R at Waterloo, Nebr 06800500) S064 06033

Salt Creek Basin

SC-1 Olive Br at SW 86th St, Lancaster Co C055 00910

SC-2 Hickman Br at S 110th St, Lancaster Co C055 03705

SC-3 Salt Cr at S55F (Salt Cr at Roca, Nebr 06803000) SS55F 00229

SC-4 Beal Slough at N2 S002 46092

SC-5 Haines Br at Midway Rd, Lancaster Co C055 04405P

SC-6 S Br Middle Cr at SW 126th St, Lancaster Co C055 60315

SC-7 Middle Cr at US6 S006 30732

SC-8 Middle Cr at SW 40th St, Lancaster Co (Middle Cr at SW 40th St at Lincoln, Nebr 06803170) C055 31520

SC-9 Oak Cr at N66 S066 05451

SC-10 N Oak Cr at N66 S066 06060

SC-11 Oak Cr at US34 S034 31754

Table 1. Primary study sites for documentation of streambed adjustment and channel widening in eastern Nebraska, 

1996 to 1999—Continued

[ID, identification; NDOR, Nebraska Department of Roads; No., number; Cr, Creek; N#, Nebraska State route; Nebr, Nebraska; W, west; US#, U.S. route; CR, 

County Road; Co, County; sec, section; T#X, township; N, north; R#X, range; E, east; NW, northwest; SE, southeast; S, south; St, Street; Rd, Road; Br, Branch; 

trib, tributary; L#X, State connecting link; Ave, Avenue; S#X, State spur; R, River M, Middle; Fk, Fork; SW, southwest]

Site ID Station name1 NDOR bridge ID
METHODS 10

Salt Creek Basin—Continued

SC-12 W Oak Cr at US34 S034 31644

SC-13 Salt Cr at N 27th St, Lincoln (Salt Cr at Lincoln, Nebr 06803500) C055 22535

SC-14 Little Salt Cr at Davey Rd, Lancaster Co unknown/Culvert

SC-15 Little Salt Cr at Branched Oak Rd, Lancaster Co C055 11215

SC-16 Little Salt Cr at NW 12th St, Lancaster Co C055 41935

SC-17 Deer Cr at Davey Rd, Lancaster Co C055 21013

SC-18 Deer Cr at Branched Oak Rd, Lancaster Co C055 11220

SC-19 Little Salt Cr at Raymond Rd, Lancaster Co C055 11415

SC-20 Little Salt Cr at Waverly Rd, Lancaster Co C055 01815

SC-21 Little Salt Cr at Arbor Rd, Lancaster Co (Little Salt Cr near Lincoln, Nebr 06803510) C055 02205P

SC-22 Salt Cr at 70th St, Lincoln (Salt Cr at 70th St at Lincoln, Nebr 06803513) C055 13120

SC-23 Stevens Cr at Havelock Ave, Lancaster Co (Stevens Cr near Lincoln, Nebr 06803520) C055 32815

SC-24 Rock Cr at Ashland Rd, Lancaster/Saunders Co C055 10230

SC-25 Rock Cr at Agnew Rd, Lancaster Co (Rock Cr near Ceresco, Nebr 06803530) C055 00650

SC-26 Salt Cr at CR, Cass Co (Salt Cr at Greenwood, Nebr 06803555) C013 01405P

SC-27 N Fk Wahoo Cr at N79 S079 02719

SC-28 N Fk Wahoo Cr at N92 S092 44217

SC-29 Cottonwood Cr trib at CR "S" 2200, Butler Co (Cottonwood Cr trib above Dam 6B near Prague, 

Nebr 06803935)

C078 01805

SC-30 Cottonwood Cr at S78E SS78E 00387

SC-31 Sand Cr trib at CR 24, Saunders Co C078 11765

SC-32 Sand Cr at CR 22, Saunders Co C078 22150

SC-33 Wahoo Cr at N63 (Wahoo Cr at Ithaca, Nebr 06804000) S063 03460

SC-34 Johnson Cr at CR G, Saunders Co (Johnson Cr near Memphis, Nebr 06804900) C078 24260

Little Nemaha River Basin

LNR-1 Little Nemaha R at N43 S043 01441

LNR-2 Silver Cr at S66A SS66A 00269

LNR-3 Hooper Cr at N43 S043 02621

LNR-4 Hooper Cr at N2 S002 48008

LNR-5 Little Nemaha R at N50 (Little Nemaha R near Syracuse, Nebr 06810500) S050 05049

LNR-6 Muddy Cr at CR "O", Otoe Co C066 13035

LNR-7 S Fk Little Nemaha at CR "N", Otoe Co C066 02810

LNR-8 S Fk Little Nemaha R at N50 S050 04149

LNR-9 Coon Cr at N50 S050 03929

LNR-10 Spring Cr at US136 S136 21474

LNR-11 Spring Cr at CR, Johnson Co (sec 5/8, T6N, R12E) C049 10445

LNR-12 N Fk Little Nemaha at N50 S050 05900

LNR-13 N Fk Little Nemaha at CR "L", Otoe Co S002 49685

LNR-14 Little Nemaha R at N67 near Talmage S067 04771

LNR-15 Rock Cr at N128 S128 01489

LNR-16 Rock Cr at N67 S067 03578

LNR-17 Little Nemaha R at US136 (Little Nemaha R at Auburn, Nebr 06811500) S136 23131

Table 1. Primary study sites for documentation of streambed adjustment and channel widening in eastern Nebraska, 

1996 to 1999—Continued

[ID, identification; NDOR, Nebraska Department of Roads; No., number; Cr, Creek; N#, Nebraska State route; Nebr, Nebraska; W, west; US#, U.S. route; CR, 

County Road; Co, County; sec, section; T#X, township; N, north; R#X, range; E, east; NW, northwest; SE, southeast; S, south; St, Street; Rd, Road; Br, Branch; 

trib, tributary; L#X, State connecting link; Ave, Avenue; S#X, State spur; R, River M, Middle; Fk, Fork; SW, southwest]

Site ID Station name1 NDOR bridge ID
11 Streambed Adjustment and Channel Widening in Eastern Nebraska

Little Nemaha River Basin—Continued

LNR-18 Whiskey Run at CR, Nemaha Co (sec 12/13, T4N, R15E) C064 13060

LNR-19 Little Nemaha R at N67 near Nemaha S067 01234

Big Nemaha River Basin

BNR-1 N Fk Big Nemaha R at SE 148th St, Lancaster Co C055 04305

BNR-2 M Br Big Nemaha R at S34B SS34B 00455

BNR-3 M Br Big Nemaha R at N41 S041 08540

BNR-4 Yankee Cr at CR, Johnson Co (near center of S 1/2, sec 8, T4N, R9E) C049 00305P

BNR-5 Yankee Cr at US136 S136 20392

BNR-6 N Fk Big Nemaha at US136 S136 20939

BNR-7 Long Branch Cr at N62 S062 00820

BNR-8 Kirkham Cr at CR, Richardson Co (near center sec 32, T3N, R13E) C074 00305P

BNR-9 N Fk Big Nemaha R at N105 (N Fk Big Nemaha R at Humboldt, Nebr 06814500) S105 00703

BNR-10 Turkey Cr at CR, Pawnee Co (sec 3/4, T3N, R9E) C067 00735

BNR-11 Turkey Cr at N8 S008 11290

BNR-12 Johnson Ck at CR, Pawnee Co (sec 25/30, T1N, R10/11E) C067 02505

BNR-13 S Fk Big Nemaha at N8 S008 12578

BNR-14 Big Nemaha R at US73 (Big Nemaha R at Falls City, Nebr 06815000) S073 00248

BNR-15 Muddy Cr at N105 S105 02688

BNR-16 Muddy Cr at US75 S075 01884

BNR-17 Muddy Cr at US73 S073 01612

Big Blue River Basin

BBR-1 Big Blue R at CR "D", Butler Co (Big Blue R at Surprise, Nebr 06879900) C012 00705

BBR-2 N Br Big Blue R at S12E SS12E 00100

BBR-3 Kezan Cr at N15 S015 08602

BBR-4 N Br Big Blue R at CR "J", Butler Co C012 01915

BBR-5 Big Blue R at CR 2250, Saline Co (Big Blue R near Crete, Nebr 06881000) C076 14315P

BBR-6 Turkey Cr at N41 S041 05764

BBR-7 Turkey Cr at N103 S103 02465

BBR-8 Indian Cr trib at US77 S077 03378

BBR-9 Indian Cr at US77 (Indian Ck at Beatrice 06881450) S077 02364

BBR-10 Big Blue R at US77 S077 02160

BBR-11 Big Indian Cr at CR, Gage Co (sec 33/4, T2/11N, R5E) C034 06210

BBR-12 Big Indian Cr at US77 S077 00775

BBR-13 Big Blue R at N8 (Big Blue R at Barneston, Nebr 06882000) S008 08619

1 Naming convention for sites is as follows: Stream name; U.S. route, State route, county road, or municipal street. Where a county road or 

municipal street is used, the county or municipality name follows the site name. Where the county road or municipal street name is not known, the section,

township, and range location are given. Where sites are located at a USGS gaging station, the station name and number are listed in parenthesis.

Table 1. Primary study sites for documentation of streambed adjustment and channel widening in eastern Nebraska, 

1996 to 1999—Continued

[ID, identification; NDOR, Nebraska Department of Roads; No., number; Cr, Creek; N#, Nebraska State route; Nebr, Nebraska; W, west; US#, U.S. route; CR, 

County Road; Co, County; sec, section; T#X, township; N, north; R#X, range; E, east; NW, northwest; SE, southeast; S, south; St, Street; Rd, Road; Br, Branch; 

trib, tributary; L#X, State connecting link; Ave, Avenue; S#X, State spur; R, River M, Middle; Fk, Fork; SW, southwest]

Site ID Station name1 NDOR bridge ID
METHODS 12

Table 2. Supplemental study sites for documentation of streambed adjustment in eastern Nebraska

[ID, identification; NDOR, Nebraska Department of Roads; S, south; Cr, Creek; trib, tributary; CR, County Road; Co, County; SW, southwest; NW, northwest; sec, 

section; T#X, township; N, north; R#X, range; E, east; nr, near; Nebr, Nebraska; SE, southeast; --, not available; US#, U.S. route; NE, northeast; W, West; St, street; 

UP, Union Pacific; RR, Railroad; N#, Nebraska State route; I-80, Interstate 80; Rd, road; BNSF, Burlington Northern Santa Fe; L#X, State connecting link; Blvd, 

Boulevard; Br, Branch; Ave, Avenue; Kans, Kansas]

Site ID Station name1 NDOR bridge ID

Missouri River Tributaries Basin

MRT-A S Omaha Cr trib at CR, Thurston Co (SW1/4 NW1/4 sec 35, T25N, R8E)

(S Omaha Cr trib nr Walthill, Nebr 06600600)

--

MRT-B S Omaha Cr at CR, Thurston Co (SW1/4 SE1/4 sec 23, T25N, R8E)

(S Omaha Cr nr Walthill, Nebr 06600700)

--

MRT-C New York Cr trib at CR, Washington Co (SW1/4 SW1/4 sec 4, T19N, R10E)

(New York Cr trib nr Spiker, Nebr 06608700)

--

MRT-D New York Cr at US75

(New York Cr at Herman, Nebr 06609000)

S075 12479

MRT-E Honey Cr at CR, Nemaha Co (SW1/4 NE1/4 sec32, T6N, R15E)

(Honey Cr nr Peru, Nebr 06810060)

--

Papillion Creek Basin

PC-A W Papillion Cr at Dodge St, Omaha --

PC-B W Papillion Cr at UP RR, Omaha (SE1/4 NW1/4 sec 22, T15N, R11E) --

PC-C W Papillion Cr at Pacific St, Omaha --

PC-D W Papillion Cr at N50 S050 09127

PC-E S Papillion Cr at 156th St, Omaha C077 11925

PC-F Wehrspann Cr at N370 S370 00376

PC-G S Papillion Cr at 132nd St, Omaha --

PC-H W Papillion Cr at 66th St, Omaha C077 13315P

PC-I Big Papillion Cr at 156th St, Douglas Co C028 13320

PC-J Big Papillion Cr at I-80 S080 44846

PC-K Little Papillion Cr at I-80 S080 44984

PC-L Little Papillion Cr at US275 S275 18587

PC-M Big Papillion Cr at Cornhusker Rd, Sarpy Co C077 30630

Platte River Tributaries Basin

No supplemental study sites used in this basin

Elkhorn River Basin

No supplemental study sites used in this basin

Salt Creek Basin

SC-A Beal Slough at Pine Lake Rd, Lincoln --

SC-B Beal Slough at 56th St, Lincoln --

SC-C Beal Slough at BNSF RR, Lincoln (SE1/4 SE1/4 sec 8, T9N, R7E) --

SC-D Beal Slough at N2 S002 46191

SC-E Beal Slough at 48th St, Lincoln --

SC-F Beal Slough at 40th St, Lincoln --

SC-G Beal Slough at BNSF RR, Lincoln (SE 1/4 NE1/4 sec 7, T9N, R7E) --

SC-H Beal Slough at L55W SL55W 00197
13 Streambed Adjustment and Channel Widening in Eastern Nebraska

Salt Creek Basin—Continued

SC-I Beal Slough at Pioneers Blvd, Lancaster Co --

SC-J Beal Slough at UP RR, Lancaster Co (SE1/4 SW1/4 sec 2, T9N, R6E) --

SC-K Haines Br at SW 98th St, Lancaster Co --

SC-L Haines Br at Coddington Ave, Lancaster Co --

SC-M Haines Br at US77 S077 06027

SC-N Rock Cr at N 70th St, Lancaster Co --

SC-O Rock Cr at N 84th St, Lancaster Co --

SC-P Rock Cr at N 112th St, Lancaster Co --

SC-Q Rock Cr at Little Salt Rd, Lancaster Co --

SC-R Rock Cr at Rock Creek Rd, Lancaster Co --

SC-S Rock Cr at Davey Rd, Lancaster Co --

SC-T Rock Cr at Branched Oak Rd, Lancaster Co --

SC-U Rock Cr at 162nd St, Lancaster Co --

SC-V Rock Cr at Greenwood Rd, Lancaster Co --

SC-W Sand Cr at US77 S077 09410

SC-X Salt Cr at US6 (Salt Cr nr Ashland, Nebr 06805000) S006 33987

Little Nemaha River Basin

LNR-A Wolf Cr at CR, Otoe Co (NE1/4 NE1/4 sec 18, T8N, R11E) (Wolf Cr nr Syracuse 06810300) --

LNR-B Muddy Cr at N50 S050 04571

Big Nemaha River Basin

BNR-A Turkey Cr at CR, Nemaha Co, Kans (SW1/4 SW1/4 sec 20, T1S, R12E) 

(Turkey Cr nr Seneca, Kans 06814000)

--

Big Blue River Basin

No supplemental study sites used in this basin

1Naming convention for sites is as follows: Stream name; U.S. route, State route, county road, or municipal street. Where a county road or 

municipal street is used, the county or municipality name follows the site name. Where the county road or municipal street name is not known, the 

section, township, and range location are given. Where sites are located at a USGS gaging station, the station name and number are listed in 

parenthesis.

Table 2. Supplemental study sites for documentation of streambed adjustment in eastern Nebraska—Continued

[ID, identification; NDOR, Nebraska Department of Roads; S, south; Cr, Creek; trib, tributary; CR, County Road; Co, County; SW, southwest; NW, northwest; sec, 

section; T#X, township; N, north; R#X, range; E, east; nr, near; Nebr, Nebraska; SE, southeast; --, not available; US#, U.S. route; NE, northeast; W, West; St, street; 

UP, Union Pacific; RR, Railroad; N#, Nebraska State route; I-80, Interstate 80; Rd, road; BNSF, Burlington Northern Santa Fe; L#X, State connecting link; Blvd, 

Boulevard; Br, Branch; Ave, Avenue; Kans, Kansas]

Site ID Station name1 NDOR bridge ID
14 Streambed Adjustment and Channel Widening in Eastern Nebraska

streambed-elevation point for documentation of 

streambed-elevation adjustment. The survey data also 

were used to reveal recent stream-channel widening. 

Because they may have been potential indicators of 

streambed gradational status, particle-size analyses 

also were performed on samples taken from the 

streambeds of most of the primary sites. 

Dendrochronological techniques as described by 

Simon and Hupp (1992) and Phipps (1985) were 

explored to document past stream-channel widening 

using botanical evidence. These techniques are based 

on the effects of mass wasting on tree growth. A 

general history of the channel widening at a site can be 

discerned by correlating the effects on trees with the 

geometry of the failure masses. Few sites were 

observed where both affected trees and failure masses 

were still present; therefore, these techniques were not 

used for this study.

Topographic Data

Topographic data were collected at each of the 

primary sites between 1996 and 1999 by surveying a 

reach of the channel. Surveys were conducted at least 

twice at each site so that recent channel widening 

could be documented. On average, 23 months elapsed 

between the two surveys, but all were separated by at 

least 15 months. 

Surveys were performed using a Sokkia Set II B 

electronic total station. A local coordinate system of 

northing, easting, and elevation was referenced to 

horizontal and vertical control points at each site, with 

the zero point for the horizontal coordinates usually 

established on the upstream or downstream edge of the 

bridge structure over what was estimated to be the 

deepest part of the channel. This allowed each site to 

be surveyed later on the same coordinate system. The 

surveying instrument was approximately referenced to 

north by means of a magnetic compass with adjustments for declination as determined from USGS 

1:100,000-scale topographic maps. Once the coordinate system had been set, the zero point was verified to 

ensure that the setup was correct. The topographic 

survey then was made. The zero point or other control 

point(s) were surveyed again at the completion of the 

survey to confirm that the instrument was still 

measuring within 1 cm of the known coordinates. All 

survey points were corrected for the effects of temperature and atmospheric pressure, and for curvature and 

refraction. 

First-Round Survey

The initial channel-reach surveys generally 

consisted of a combination of channel cross sections 

and selected ground and channel-bed shots of specific 

channel features including those to define the top of 

the channel bank, and the thalweg, which is the 

deepest point in the channel. The reaches surveyed 

were typically three to four channel widths long, and 

all surveys included a cross section at either the 

upstream or downstream edge of the bridge or culvert 

structure for use in the streambed-gradation analysis 

of the site. Some surveys were made both upstream 

and downstream from the structure with as many as 

20 cross sections; however, most were made on only 

one side of the structure with about four cross sections. 

Because of overall time constraints or dense tree cover 

at the time of surveying, some later surveys consisted 

only of channel cross sections. At sites with historical 

surveys, efforts were made to resurvey the same cross 

sections, but this proved to be very difficult without 

known horizontal control points to reference. Because 

this study focused on channel widening caused by 

streambed elevation gradation rather than by lateral 

channel migration, straight reaches were preferred for 

surveying. However, in many cases, no straight 

reaches were present.

Second-Round Survey

For most sites, the second round of surveys 

consisted primarily of shots along the top edges of 

failures or along cut banks at or near the top of the 

channel banks. This was done to identify areas where 

potential channel widening had occurred. Although 

failures in the lower parts of the channel ultimately 

increase the probability of top-bank widening, the 

documentation and comparison of every failure within 

a channel reach was time-prohibitive and would have 

been limited by the level of failure definition between 

the two surveys. A short reach of the thalweg also was 

surveyed at each site to add to the streambed-elevation 

data set for the site.

Reference to National Geodetic Vertical Datum of 1929

The surveys needed to be referenced to a 

common datum to compare streambed-elevation data 

to surveys from previous studies. Past survey data 

were generally tied to the National Geodetic Vertical 

Datum of 1929 (NGVD29), which also was known as 
METHODS 15

the Sea Level Datum of 1929 (Nebraska Department 

of Natural Resources, 2003). Thus, the NGVD29 was 

used as the reference datum for this study. Reference 

points or benchmarks relating to NGVD29 already 

existed at most daily discharge-gaging stations. In 

such cases, those reference points were used in the 

initial surveying setup. For the remaining sites and for 

discontinued daily gaging stations where the old reference points had been destroyed, referencing to 

NGVD29 was accomplished in one of two other ways: 

(1) By surveying the road grade at the centerline of the 

bridge at each abutment and referencing to the 

NGVD29 elevation of similar points given in the 

“as-built” plans for the bridge, the NGVD29 elevation 

of the survey could be established within an assumed 

vertical precision of 10 cm; (2) when elevations were 

not available in the bridge plans, closed transits were 

run to third-order accuracy or higher (providing 

vertical precision within 2 cm for a typical transit of 

3.2 km) (Kennedy, 1990) between one of the control 

points at the site and the nearest available vertical 

control. It was assumed that the variance to streambed 

elevation caused by short-term adjustment processes 

such as scour was at least 10 cm; therefore, the precision for referencing NGVD29 was acceptable for both 

methods. Although the closed transits were more 

precise, they were significantly more time consuming 

and were used only if other options were not available.

Streambed Particle-Size Analyses

Streambed samples were collected at 146 of the 

primary sites using a BMH-53 sampler (Edwards and 

Glysson, 1999) between 1998 and 1999. The BMH-53 

is a piston-type sampler 5 cm in diameter that collects 

streambed material to a depth of 20 cm. Point samples 

were collected from the thalweg at each site. Particlesize distributions of the samples were determined by 

the Soil and Plant Analytical Laboratory of the 

University of Nebraska–Lincoln. A four-point 

hydrometer test was performed on all samples for 

particle-size analysis. Additionally, sieve analyses 

were done on samples dominated by coarse particles. 

Based on the particle-size distributions, the laboratory 

made a determination of soil textural classification 

(Schoeneberger and others, 1998) using National Soil 

Information System (NASIS) codes. At sites where the 

individual streambed particles were larger than the 

piston diameter on the BMH-53, samples were not 

collected, although it could be assumed that the 

median grain size was greater than 5 cm.

Characterization of Streambed 

Adjustment

Streambed adjustment was determined by 

compiling data sets of streambed elevation over time 

for each site and by documenting the disturbances that 

may have taken place in a drainage basin. The connection between disturbance and streambed gradation was 

presumed at some sites, especially those that had been 

straightened. However, at many sites, multiple disturbances occurred that all potentially could have led to 

gradation, and no connection was established.

Streambed Elevation History

For each site, the change in streambed elevation 

over the time period of the data set provided a general 

measure of streambed gradation. The change was 

calculated by subtracting the earliest elevation point in 

the data set from the latest point. Each data set from 

which these measures were computed is included in 

electronic format on the compact disc provided with 

this report. For some data sets, distinct episodes of 

streambed gradation can be identified that are not 

revealed by the measure of total change. Additionally, 

the median grain-size diameter and textural class 

of the streambeds from the 1998–99 sampling of 

146 primary sites is given.

Efforts were made to produce predictive 

streambed-gradation equations from the empirical data 

sets following the methods of Simon (1994), but the 

complexity of channel responses caused by the 

multiple disturbances that occurred in each basin 

limited the applicability of these methods. Instead, the 

magnitude of streambed change for the time period of 

the data set was determined for each site.

For each site, a time-series data set of thalweg 

elevations was compiled. Because the topographic 

surveys of this study provided only data from the years 

1996 to 1999, historical data were compiled from 

several sources to expand the temporal range of the 

data sets. The data came from surveys, bridge plans, 

tapedown measurements from bridge inspections, 

discharge measurements, tapedown measurements 

from gaging-station inspections, median water-surface 

elevations from rating curves in gaging-station 

records, historical accounts, channel modification 

design plans, and previous studies (table 3). Historical
16 Streambed Adjustment and Channel Widening in Eastern Nebraska

data that were not already adjusted to NGVD29 were 

adjusted using the methods listed in table 4.

Because data were obtained from a variety of 

sources, several different sources of uncertainty were 

introduced. These uncertainties were a result of differences in the methods of data collection, the correlation 

of the data to a common datum, and the location and 

date the data were collected. Although the magnitude 

of the uncertainties was unknown, it is realistic to 

assume that some variance in streambed elevation 

could be attributed to these uncertainties.

The compiled data were collected using several 

different methods: 

1. Survey methods were considered the most accurate. 

The main concern with surveys lies in the 

assumption that the survey crew identified the 

thalweg, which is of interest to this study. In 

some cases, the surveys only went to the water 

surface, which made the data less useful. 

2. “As-built” bridge plans often included the thalweg 

elevation. When data from plans were used, it 

was assumed that the actual disturbance to the 

thalweg during construction did not deviate 

significantly from the plans. 

3. Chen and others (1999) compiled median watersurface elevations (MWSE) for selected stations 

in the study area. These were the water levels that 

corresponded to a reference low-water discharge 

for each of the stage-discharge relations (rating 

curves) ever used at the site. These relations were 

updated periodically whenever significant 

changes to the channel (degradation, aggradation, 

channel widening) occurred. The use of the 

median as the reference discharge isolated 

changes to the low-water channel, thereby

Table 3. Sources and types of historical streambed-elevation data

[Source: FEMA, Federal Emergency Management Agency; NRCS, Natural Resources Conservation Service; USACE, U.S. Army Corps of Engineers; 

USGS, U.S. Geological Survey; NDOR, Nebraska Department of Roads; NNRC, Nebraska Natural Resources Commission (now the Nebraska Department of Natural Resources); UN–L, University of Nebraska–Lincoln; NGVD29, National Geodetic Vertical Datum of 1929; MWSE, median watersurface elevation]

Source Types of data Method used to reference to NGVD29

NDOR Surveys

"As built" bridge plans

Tapedown from bridge inspections

Data used NGVD29 datum

Data used NGVD 29 datum

Subtracted from grade elevation

USGS Surveys

Discharge measurements from 

gaging stations

Tapedowns from gaging-station 

inspections

MWSE

Gage height added to gage datum in NGVD29.

Maximum depth subtracted from stage, then added 

to gage datum in NGVD29.

Subtracted from reference gage height, then added 

to gage datum in NGVD29.

Added to gage datum in NGVD29.

NRCS Surveys Data used NGVD29 datum.

NNRC Surveys Data used NGVD29 datum.

USACE Surveys

Historical accounts

Channel modification designs

Gaging-station records

Data used NGVD datum.

Estimated from current channel geometry.

Estimated from current flood-plain elevations.

Added to gage datum in MSL.

FEMA Surveys of the water surface 

profiles, often based on aerial 

photogrammetry

Data used NGVD29 datum.

UN–L Previous studies detailing channel 

modification designs

Estimated from current flood-plain elevations.

County Engineers “As built” bridge plans

Tapedowns from bridge inspections

Data used NGVD29 datum.

Subtracted from grade elevation.

Individual landowners Historical accounts Estimated from current channel geometry.
METHODS 17

preventing the effects of channel widening from 

being included. Because the MWSE data corresponded to the water surface, estimates of the 

thalweg were made from the MWSE data by 

setting the MWSE value for a particular date 

equal to a known thalweg value from a similar 

time frame and then shifting the rest of the 

MWSE values accordingly. This was done for 

comparison purposes, and the amount by which 

the data were shifted is noted in the streambedelevation data set. 

4. Chen and others (1999) also compiled records of 

the stage and corresponding discharge at several 

USACE gaging stations. By using a low reference discharge, the corresponding stage could be 

identified for each year published. As in the 

previous method, changes to the stage for the 

same discharge were related to changes in the 

channel characteristics. These data were adjusted 

to the thalweg in the same manner as that of the 

MWSE. 

5. When MWSE data were not available, but streamflow measurements had been made, these 

measurements could be used to characterize the 

submerged channel with a rough approximation 

of the thalweg. However, their purpose was to 

characterize streamflow in evenly spaced intervals rather than to define geomorphic features. 

6. Tapedown measurements often were provided with 

bridge and gaging-station inspections. These 

usually were made to the center of the stream, 

which was not always the thalweg. Additionally, 

the reference point from which the tapedown was 

made (and the elevation of that point) had to be 

estimated. In many cases, these data were not 

used because of obvious inconsistencies with 

survey and plan data. 

7. The USGS operated several sites as peak-stage indicator sites. As part of these operations, frequent 

measurements of water level, rather than streamflow, were made during both high and low waterlevel conditions. It was assumed that the effects 

of channel widening would be minimized in the 

low water-level measurements; these measurements are included in the streambed data set and 

often show trends over time. It should be noted 

that variability introduced from fluctuation in 

water level is inherent in these data.

8. Historical accounts were obtained from previous 

studies as well as individual landowners. Typical 

statements were, “the channel was only X feet 

deep 30 years ago,” or “the channel had suffered 

X feet of degradation since straightening in 

1915.” These accounts were subjective and often 

were used only as evidence of past change. 

However, some of the previous studies with 

historical accounts of degradation also had 

survey data corresponding to the particular study, 

which allowed for estimation of streambed elevation prior to the onset of degradation. 

9. Aerial photogrammetry was used mainly in the 

FEMA Flood Insurance Studies and involved 

estimating elevation data from aerial photoTable 4. Methods for referencing data sets with the National Geodetic Vertical Datum of 1929

[NGVD29, National Geodetic Vertical Datum of 1929; MWSE, median water-surface elevation]

Method for referencing to NGVD29 Assumptions Data-collection methods that referenced 

NGVD29 this way

A documented benchmark was used 

as a known elevation.

The given benchmark elevation was accurate. Surveys from previous studies, bridge plans, 

discharge measurements, MWSE, and 

gaging-station records.

The road grade was used as a known 

elevation.

The grade elevation was referenced using a 

benchmark.

There was a negligible amount of wear (from 

traffic or seasonal swelling) and bridge 

maintenance work (like resurfacing).

Surveys from this study, tapedowns.

The flood-plain elevation or another 

reference channel characteristic 

was used as a known elevation.

A reference characteristic (like the flood-plain 

elevation) remained unchanged between the 

period of the unknown data set and that from 

a known data set.

Historical accounts, construction plans.
18 Streambed Adjustment and Channel Widening in Eastern Nebraska

graphs. Often, ground surveys also were done in 

places to “ground-truth” the data. 

10. Straightening/dredging construction plans were 

excellent for identifying disturbances to the 

channel, but it was difficult to obtain actual 

thalweg elevations from them because the plans 

did not contain site-specific data, but rather 

generic specifications of the channel. In those 

cases where a designed channel depth was given, 

the design elevation was estimated by subtracting 

the depth from the elevation of the existing flood 

plain.

The way that the data were referenced to 

NGVD29 also produced uncertainty (table 4). A data 

point that was tied in using a benchmark was considered more reliable than one that was estimated from 

the elevation of the surrounding flood plain. Many of 

the historical data were already tied in to NGVD29, 

although the methods by which they were referenced 

were generally not given. It was assumed that a documented benchmark was used to tie the data in, but less 

precise methods may have been used.

To compare the thalweg elevation points over 

time and document change, each data point had to be 

from the same location. The bridge was used as a 

reference point, but some data sets were collected 

away from the bridge. The farther away the data were 

collected from the bridge, the less applicable they 

became for comparison purposes. 

The final level of uncertainty came from the 

date associated with each data set. In many previous 

studies, the date of the survey was not given. The 

publication date was used instead. For other surveys 

and most of the bridge plans, only the year of the data 

collection was known. 

Influences on the Streambed

In addition to the site-specific streambed-elevation data sets, basin-specific characteristics affecting 

streambed elevation were noted. This was done to 

provide background information when the streambed 

gradational history was considered at a particular site 

or at the larger scale of the basin. Potential disturbances that may have led to streambed adjustment 

were documented from several sources. All observed 

knickpoints and grade-control structures within the 

basin also were identified. 

Disturbances

Because human-caused disturbances related to 

stream-channel straightening efforts were the primary 

motivation behind this study, the identification of 

disturbances was focused on documenting these 

projects. The existence of drainage districts in eastern 

Nebraska and sometimes the corresponding channelmodification plans were stated in previous studies 

such as Brook and others (1892), Farrar and Gersib 

(1991), Ferrell (1996), Kerstetter (1992), Mears 

(1912), Moore (1915), Nebraska Department of Roads 

and Irrigation (1954), and U.S. Army Corps of Engineers (1963). Altered stream reaches were identified 

using 1:100,000-scale maps, aerial photographs, and 

historical accounts from landowners. 

In addition to disturbances related to channel 

modifications, other human-caused disturbances were 

identified, although their effects in eastern Nebraska 

may have been minimal. Agricultural development 

and urbanization were explored. Numerous small 

dams located in the upper regions of several of the 

basins (Natural Resources Conservation Service 

(1996b) also were documented. These indirect disturbances could lead to changes in the streamflow and 

sediment load. Direct changes in these attributes were 

not explored because few data on sediment load in the 

study area are available, and an extensive assessment 

of streamflow change was outside the scope of the 

study. However, cursory examination of historical 

flows at several USGS streamflow-gaging stations in 

the study area indicates that high flows, which would 

be the flows that dominate streambed adjustment, have 

occurred at a relatively constant frequency over the 

period of record for those stations. It is also unlikely 

that sediment-load changes, if they did occur, contributed to significant long-term streambed adjustment 

because, as stated previously, the coarse sediment load 

that influences the streambed may have been inconsequential in the loess areas of eastern Nebraska.

Knickpoints

Because headward-progressing knickpoint 

migration was probably the primary cause of 

streambed degradation in eastern Nebraska, any 

observed knickpoints were documented. However, 

because only short reaches of streams could be 

observed from bridges, this is by no means a complete 

record of all knickpoints in the region.
METHODS 19

Grade-Control Structures

Grade-control structures, either natural or 

constructed, were identified because they would affect 

the continuity of headward-progressing streambed 

degradation. A complete record of these structures was 

not available, and those presented in this report were 

either observed during the course of the study or were 

documented in other studies. In most cases, these 

structures were the response to degradation that had 

occurred previously. Either a drop structure or lowhead dam was constructed across the stream, or degradation exposed bedrock or pipelines, all of which 

would affect streambed adjustment and temporarily 

(over the duration of the structure) halt or dampen the 

progression of knickpoints (Simon, 1994). Although 

culverts could be considered grade-control structures, 

these were too numerous to document in full and were 

associated mainly with small streams in the upper 

parts of drainage basins. 

Characterization of Recent Channel 

Widening

Widening over a period of about 2 years was 

documented by comparing the first-round and secondround survey data at primary sites to identify failures 

occurring at the top of the channel bank (TOB). These 

analyses were done on a subset of 73 of the primary 

sites that had extensive topographic survey data rather 

than only cross-sectional data. Comparing historical 

cross-sectional data over a longer period of time was 

explored as another method to document widening at 

the sites. However, with no horizontal control available for historical cross-sectional surveys and geomorphic variability along the stream channel, these 

comparisons were not made. 

Contouring First-Round Survey Data

Topographic information provided by the firstround survey data identified many channel features 

such as TOB lines, failure surfaces, water surfaces, 

and thalwegs. From these data, contour lines were 

constructed using the contouring and surface mapping 

features of Surfer (Golden Software, Inc., 1995). For 

each reach, a surface grid was created from the survey 

data by using triangulation methods. Contour lines 

with elevation intervals of 0.5 m were developed from 

the grid and plotted on maps (fig. 4A). The first-round 

data were plotted with labels regarding each channel 

feature represented. When sufficient data were available, first-round data points were connected with 

yellow lines representing the TOB between the points.

Overlay of Second-Round Survey Data

Second-round TOB points were posted in red on 

top of the first-round contour plot (fig. 4A). Secondround surveys identified recent failures (indicated by 

vertical cut banks) along the tops of channel banks. 

When the second-round data plotted outside of the first 

round TOB line (and onto the flood plain), it was 

assumed that a failure had occurred there, and these 

TOB widening points were used in the characterization 

of the individual failure.

Characterization of Individual Top-of-Bank 

Failures

The basic geometry of each identified failure 

was documented. The TOB failure was defined by the 

second-round widening points and the adjacent 

second-round points that had not widened (fig. 4B). 

The failure was divided into segments that corresponded to the widening points. The observed 

widening of each segment, wi

, was then the distance 

between the failure edge and the first-round TOB line. 

The length of each segment, li

, was measured as the 

distance along the baseline between widening points i

and i–1 (fig. 4B). 

From these measurements of width and length, 

the area of the failure was computed. The area of an 

individual slice of the failure, Ai

, was calculated by 

multiplying the respective failure widening distance, 

wi

, by the average of the two adjacent lengths, li and 

li+1. Using this method, it was assumed that the 

measured widening distance at each second-round 

widening point represented the mean widening 

distance in a partial rectangular area (fig. 4B). The sum 

of the slice areas determined the area of the failure, Af

, 

and the sum of the length segments determined the 

failure length, lf

. The weighted failure width, wf, was 

calculated by dividing the failure area by its length. 

The dimensions of individual failures were then used 

to summarize widening and to compute widening rates 

at each site.

Computation of Widening Rates

Once all of the failures were characterized at 

each site, widening rates were computed for the entire 

site. All of the failure areas were summed into a total 

failed area, At

. The unit widening (in failed area per 

unit length of TOB) for the entire site then was
20 Streambed Adjustment and Channel Widening in Eastern Nebraska

computed by dividing At by twice the length of the 

survey reach (because both banks were analyzed). The 

unit widening was divided by the time between firstand second-round surveys to compute the widening 

rate, expressed in meters of widening per year. 

The widening rates produced by this method 

were computed for comparison purposes and are 

applicable to the 2-year period between the first- and 

second-round surveys only. As stated by Simon and 

Hupp (1992), bank failures in cohesive materials occur 

through discrete mass-wasting processes. Therefore, 

the computed widening rates are not exact measures of 

a continuous process, but average measures of an 

episodic process. 

STREAMBED ADJUSTMENT

Multiple disturbances were identified in all but 

the Big Blue River Basin. Additionally, the effects of 

grade-control structures have complicated streambed 

gradation responses at many of the sites studied. The 

majority of observed responses appear to be related to 

the various straightening efforts that have taken place 

in the study area, with streambed-elevation data sets at 

some sites showing 6 to 7 meters of degradation since 

the channel was straightened.

Straightening plans or historical accounts were 

available in the Papillion Creek, Elkhorn River, Salt 

Creek, Little Nemaha River, and Big Nemaha River 

Basins. At the sites in those basins that had been 

straightened, the original streambed elevation was estimated. Comparisons of the estimated original 

streambed elevation to the most recent data revealed 

the full magnitude of gradation response following the 

straightening. Because these espossible in a subset of 

the sites and only in certain basins, an unbiased 

comparison of gradation differences between basins is 

not possible.

A 

B Area of detail 

EXPLANATION 

Second-round surveying point

 

w Widening observed at point i l

li+

Widening 

points

wi

li+1

li

i

First-round surveying point

Contour lines and shading (as elevation

 decreases, shading gets darker blue)

First-round top-of-bank line

Second-round failure block definition 

Individual slice of the failure having an area

 of Ai

Failure length from point i–1 to point i

1 Failure length from point i to point i+1

i

Figure 4. Characterization of top-of-bank (TOB) widening between first and second rounds of surveying 

by: (A) Identifying individual failures along the TOB, and (B) characterizing the geometry of each.
21 Streambed Adjustment and Channel Widening in Eastern Nebraska

Potential Study-Area-Wide Disturbances

Two potential disturbances were identified that 

transcended drainage basin boundaries and may have 

affected streams in some or all of the study area: 

(1) Chen and others (1999) determined that long-term 

changes to the MWSE had occurred at some sites 

along the Missouri River; and (2) agricultural development in Nebraska increased steadily until 1931 

(fig. 5) (Nebraska Department of Agriculture and 

Inspection, 1957), which changed the land-use 

patterns in the study area and may have consequently 

altered streamflow and sediment-load characteristics.

Changes to the Median Water-Surface Elevation of 

the Missouri River

On the Missouri River, a navigation project and 

the construction of Gavins Point Dam in the upper end 

of the study area increased scouring energy in the 

river. Chen and others (1999) analyzed the MWSE at 

five sites on the Missouri River where it bordered 

Nebraska. They found significant downward trends at 

Yankton, South Dakota; Sioux City, Iowa; and Omaha, 

Nebraska, but insignificant trends at Nebraska City 

and Rulo, Nebraska (fig. 6). It was assumed that 

changes to the MWSE revealed streambed aggradation 

or degradation. Missouri River streambed degradation 

that occurred at the sites with downward trends could 

have migrated up into all of the basins studied except 

for the Big Blue River Basin. However, Chen and 

others (1999) found no significant changes in the 

MWSE of the Platte River, which receives the Elkhorn 

River and Salt Creek Basin flows, at Duncan, North 

Bend, or Ashland, Nebraska. A downward trend of the 

MWSE of the Platte River at Louisville, Nebraska, 

was probably caused by changes in site-specific gradation variables, such as stream width, streamflow 

discharge, or local slope (U.S. Army Corps of Engineers, written commun., 2000). 

Agricultural Development in Nebraska

As Nebraska became settled, native areas that 

were predominantly prairie were converted to cropland. There was a steady increase in the area of 

harvested crops until 1931, when the area of harvested 

crops decreased and then remained basically 

unchanged through 1990 (fig. 5) (Nebraska Department of Agriculture and Inspection, 1957). Farming 

practices exposed soils to greater erosion and altered 

the rainfall infiltration capacity of the land, thereby 

affecting the sediment load and streamflow in the 

channels. However, as stated previously, changes to 

the streamflow have not been proven conclusively. 

Although few data exist on sediment load, the coarse 

materials that affect streambed-adjustment processes 

probably do not occur in appreciable amounts in the 

loess areas of eastern Nebraska.

1860 1880 1900 1920 1940 1960 1980 2000

0

2,000

4,000

6,000

8,000

TOTAL CROP AREA 

HARVESTED, IN 

HECTARES X 1,000

Missouri River Tributary Basins

Twenty-three sites in eight minor tributary 

basins to the Missouri River were studied for 

streambed-elevation change (fig. 6). The basins 

studied were the Bow Creek, Aowa Creek, Elk Creek, 

Omaha Creek, Elm Creek, New York Creek, Weeping 

Water Creek, and Honey Creek Basins.

Documented Disturbances, Knickpoints, and 

Grade-Control Structures

Nearly all of these basins may have been 

affected by the downward trend in MWSE of the 

Missouri River. However, the correlation between the 

river and its tributaries was unpredictable because of 

inconsistency in changes to the MWSE of the river and 

the long duration of the changes (1927 to 1981) as 

documented by Chen and others (1999). Local 

drainage districts (Nebraska Department of Roads and 

Irrigation, 1954) (table 5) straightened reaches of

Figure 5. Total area of harvested crops in Nebraska, 

1866–1990.
STREAMBED ADJUSTMENT 22

EXPLANATION

Basin boundary

Missouri River Tributary straightening

Primary study site and identification 

Supplemental study site and identification 

Town

Knickpoints

Stream

Grade-control structures

0 5 10 MILES

0 5 10 KILOMETERS

Base from U.S. Geological Survey

1:100,000 digital data

Albers Equal-Area Conic projection 

Standard parallels 29 ̊30' and 45 ̊30'

central meridian -96 ̊

PAPILLION

BELLEVUE

00'

Platte River

 MRT-2

 MRT-3

 MRT- 1 MRT-4 MRT-6

 MRT-5

 MRT-8

 MRT-7

 MRT-10

 MRT-9

 MRT-B

 MRT-A

 MRT-11

 MRT-D

 MRT-C

 MRT-12a

 MRT-12b

 MRT-13 MRT-14 MRT-16

 MRT-15

 MRT-E MRT-17

NEBRASKA CITY

RULO

SIOUX CITY, IOWA

 YANKTON, SOUTH DAKOTA

OMAHA

S Omaha Creek

Elk Cre e k Otter Creek

S outh Cre e k

New York Creek

Missouri River

S Br Weeping Water Creek

Honey Creek

Weeping Water Creek

Omaha Creek

W. Bo w Creek

Bow Creek

Aowa Cree k

E ml Cree k

97 ̊30'

42 ̊30'

96 ̊30'

97 ̊

96 ̊

95 ̊30'

42 ̊

41 ̊30'

41 ̊

40 ̊30'

40 ̊

Location map

Nebraska

Study area

Study basins

MRT-13

 MRT-E

Figure 6. Location of Missouri River Tributary Basins and associated study sites in Nebraska.
23 Streambed Adjustment and Channel Widening in Eastern Nebraska

some streams lying in the Missouri River flood plain 

(fig. 6). Although no documented drainage districts 

were associated with Aowa Creek, maps of the area 

showed straightening. 

These disturbances may have led to knickpoints 

that migrated upstream throughout the basins (fig. 6). 

Knickpoints were observed in the Bow, Aowa, Elk, 

and Omaha Creek Basins. In the Aowa Creek Basin, 

knickpoints of up to 12 m in height were documented 

at the mouths of small tributaries in 1968 (Soil Conservation Service, 1968), and site MRT-8 on Elk Creek 

experienced degradation of almost 4 m (fig. 7). 

In some cases, the progression of the degradation was slowed or halted by culverts or other structures that provided grade control. Structures were 

observed in the Omaha Creek Basin; the construction 

of a rock riffle in the 1950s at site MRT-10 (fig. 6) was 

probably in response to the large amount of degradation that had already taken place there and has probably prevented more degradation from migrating 

upstream. 

Streambed Summaries

Nine of the 23 Missouri River Tributary Basins 

sites showed degradation responses greater than 1 m 

(table 6). Site MRT-8 showed the largest amount of 

change, with 3.7 m of degradation between 1931 and 

1999, and most of the change had occurred by 1960

fig. 7). The streambed materials were coarser in the 

northeastern basins of Bow, Aowa, and Elk Creeks 

than in the rest of the basins studied (table 6).

Table 5. Drainage districts associated with Missouri River Tributary Basins

Drainage district name Streams that may have been 

straightened Date drainage plans were approved

Burt-Washington County Drainage District No. 1 New York Creek August 2, 1915

Burt-Washington County Drainage District No. 2 New York Creek February 19, 1925

Dakota County Drainage District No. 2 Omaha Creek or Elk Creek April 18, 1914

Homer Drainage District Omaha Creek January 10, 1919

Dakota City Drainage District Elk Creek April 3, 1922

Omadi Drainage District Omaha Creek December 13, 1924

Dakota County Drainage District No. 5 Omaha Creek or Elk Creek July 10, 1930

Peru Drainage District No. 6 Honey Creek April 19, 1927

1900

331

332

333

334

335

336

337

ELEVATION, IN METERS ABOVE

NGVD OF 1929

1920 1940 1960 1980 2000

Figure 7. Streambed-elevation changes at Elk Creek at 

US20 (MRT-8).
STREAMBED ADJUSTMENT 24

Papillion Creek Basin

Extensive modifications in the Papillion Creek 

Basin (fig. 8) led to severe channel incision in the first 

half of the 20th century. Although flood control for the 

City of Omaha was improved by these modifications 

and subsequent incision, the bridges in this largely 

urban basin were threatened. Several grade-control 

structures were built, which affected the gradation 

response. As the watershed became more urbanized, 

streamflow characteristics were altered, which may 

have disturbed the streambed. This urbanization also 

increased the potential damage from flooding, and 

some channels were widened and excavated beginning 

in the mid-1960s, which may have further disturbed 

the Papillion Creek Basin. 

Table 6. Streambed summaries for sites in the Missouri River Tributary Basins

[ID, identification; RKM, river distance (in kilometers from the mouth); n, number of streambed elevation points used; ∆E, difference in streambed 

elevation between first and last streambed-elevation points, in meters; d50, median streambed grain-size diameter, in millimeters; GRV, very gravelly; S, 

sand; SIL, silt loam; SICL, silty clay loam; L, loam; LS, loamy sand; --, not available

Site ID RKM n ∆E

(m)

First 

year

Last 

year

d50

(mm)

Textural 

class Comments

Bow Creek Basin

MRT-1 38.0 4 –1.2 1965 1999 1.26 GRV S

MRT-2 10.4 10 –0.8 1959 1998 0.44 S

MRT-3 42.8 23 –0.2 1967 1999 0.74 S

Aowa Creek Basin

MRT-4 23.5 4 –1.0 1964 1998 0.04 SIL

MRT-5 33.2 8 –1.4 1972 1999 0.72 S

MRT-6 12.7 5 0.4 1946 1998 0.72 S

Elk Creek Basin

MRT-7 31.6 4 0.6 1990 1999 0.76 S

MRT-8 6.1 8 –3.7 1931 1999 0.03 SIL

Omaha Creek Basin

MRT-A 37.1 40 0.4 1951 1967 -- --

MRT-B 33.9 42 –3.0 1951 1999 -- --

MRT-9 29.9 21 –3.6 1940 1998 0.02 SIL

MRT-10 7.5 22 –0.8 1952 1996 0.02 SICL

Elm Creek Basin

MRT-11 1.3 6 –0.4 1933 1999 0.03 SIL

New York Creek Basin

MRT-C 26.8 49 –1.4 1951 1965 -- --

MRT-12a -- 6 –0.3 1951 1999 0.05 L

MRT-12b 19.4 3 0.5 1988 1999 0.55 LS

MRT-D 9.6 10 –0.1 1946 1975 -- -- A weir failed at the site in 1968.

Weeping Water Creek Basin

MRT-13 79.4 49 –0.8 1952 1999 0.03 SIL

MRT-14 44.7 14 –0.6 1952 1999 -- -- Cobble streambed.

MRT-15 74.6 3 –1.0 1949 1997 0.47 SL

MRT-16 10.1 48 –2.1 1931 1999 0.04 SIL

Honey Creek Basin

MRT-E 12.7 28 –0.9 1968 1978 -- --

MRT-17 8.3 4 0.3 1971 1998 0.05 L
25 Streambed Adjustment and Channel Widening in Eastern Nebraska

 6 PC-

 I PC-

 9 PC- PC-7

 1 PC- 10 PC-

 PC-8

 2 PC- 11 PC-

 A PC-

 B PC-

 C PC-

 3 PC-

 J PC-

 K PC-

 L PC- D PC-

 E PC-

 5 PC-

 G PC-

 4 PC-

 M PC-

 PC-H F PC-

 12 PCOMAHA

PAPILLION

BELLEVUE

Eagle Run

N Br Papillion

Creek

S Papillion Creek

Wehrspann

Creek

S Papillion Creek

tributary

W Papillion Creek

Big Papillion Creek

Little Papillion Creek

Cole Creek

Papillion Creek

96 ̊12'

41 ̊36'

96 ̊

41 ̊24'

41 ̊12'

Nebraska

Location Map

Study area

Study

basin 

Base from U.S. Geological Survey

1:100,000 digital data

Albers Equal-Area Conic projection 

Standard parallels 29 ̊30' and 45 ̊30'

central meridian -96 ̊00'

0 5 10 MILES

0 5 10 KILOMETERS

PC-2

PC-B

Little Papillion Creek straightening, 1965–68

Grade-control structures

EXPLANATION

Basin boundary

Original straightening

Primary study site and identification 

Supplemental study site and identification 

Town

Knickpoints

Stream

Figure 8. Location of the Papillion Creek Basin and associated study sites in Nebraska.
STREAMBED ADJUSTMENT 26

Documented Disturbances, Knickpoints, and 

Grade-Control Structures

Original Straightening 

To protect Omaha from flooding, several 

drainage districts were formed between 1910 and 1928 

(Soil Conservation Service, 1966), leading to extensive straightening of Papillion Creek and its tributaries. In addition to those districts documented by the 

Nebraska Department of Roads and Irrigation (1954) 

(table 7), historical accounts and records from the 

Nebraska State Historical Society indicate that much 

of Papillion Creek, Big Papillion Creek, and West 

Papillion Creek were straightened between 1910 and 

1913. Unfortunately, no plans were available regarding 

this work.

This straightening led to headward-progressing 

degradation, which may have been the cause of a 

knickpoint observed in a tributary to Wehrspann Creek 

in 1998 (U.S. Army Corps of Engineers, 1998). Degradation was also documented in historical accounts by 

the USACE (1967b, p. 6);

Throughout the basin, stream characteristics have been changed radically within the past 

60 years by channel straightening. The channels 

in the lower reaches of these streams have experienced considerable scour and lateral erosion 

due to the increase in slope brought by the 

channel straightening. As would be expected, the 

channel erosion has caused problems over the 

years. The widening has required longer bridges, 

and degradation has necessitated measures to 

protect against undercutting. Lowering of the 

streambed is slowly progressing upstream from 

the lower reaches of Papillion and Big Papillion 

Creeks and the West Branch, and problems are 

now being experienced in reaches farther 

upstream on these streams.

This disturbance led to the construction of 

several grade-control structures, generally at railroadbridge crossings. One of these structures, just downstream from site PC-J (table 2; fig. 8), was built in 

1942 after 2.4 m of degradation had threatened the 

bridge (U.S. Army Corps of Engineers, 1967b). 

The presence and, in some cases, alteration of 

grade-control structures affected the many Papillion 

Creek Basin streams. In 1957, at least seven structures 

were on West Papillion Creek, and South Papillion, 

Big Papillion, and Little Papillion Creeks each had 

one, according to survey data of the Soil Conservation 

Service. To prevent gully erosion in small subbasins, 

the Natural Resources Conservation Service 

constructed 27 structures (with 25 more planned) by 

1996 (Natural Resources Conservation Service, 

1996b). While in place, these structures prevented 

further degradation from migrating upstream. This 

was the case at sites PC-E, PC-D, PC-10, and PC-11 

(fig. 8). 

When structures were modified, some or all of 

the degradation that had been stopped was allowed to 

proceed upstream. On West Papillion Creek, a structure was built at site PC-3 in 1948 (fig. 9) but had been 

removed or had failed sometime prior to 1957, 

according to survey data. This led to over 5 m of 

degradation at the site, which proceeded upstream 

until it reached another structure at site PC-B.

Table 7. Drainage districts of the Papillion Creek Basin

[From Nebraska Department of Roads and Irrigation, 1954]

Drainage district name Streams that may have been straightened Date drainage plans 

were approved

Little Papillion Drainage District Little Papillion Creek March 2, 1920

East Omaha Drainage District Cole Creek October 8, 1921

Papio Drainage Ditch No. 2 Big Papillion Creek June 5, 1926

Bellevue Drainage District Papillion Creek August 4, 1921

Chalco-Portal Drainage District West Papillion Creek and South Papillion Creek March 15, 1922

Rudersdorf Drainage District West Papillion Creek, Papillion Creek, and Big Papillion Creek February 15, 1927

Zimmerman Drainage District West Papillion Creek, Papillion Creek, and Big Papillion Creek March 16, 1929

Eastern Sarpy Drainage District Papillion Creek February 28, 1951

Papio Valley Drainage District Big Papillion Creek March 8, 1926
27 Streambed Adjustment and Channel Widening in Eastern Nebraska

Although this structure failed sometime before 1999 

(when a knickpoint was observed just above the 

remnants of the structure), a comparison of data from 

the Federal Emergency Management Agency (1997) 

suggests that the structure might have failed before 

1977, allowing degradation to proceed farther 

upstream. In 1961, the grade-control structure just 

downstream from site PC-J on Big Papillion Creek 

was lowered by 1.8 m (U.S. Army Corps of Engineers, 

1967b), which allowed an equal amount of degradation to proceed upstream (table 8).

Urbanization

During the last half of the 20th century, the 

Papillion Creek Basin changed from an agricultural 

watershed to a largely urban one. Before 1940, the 

basin was dedicated primarily to agriculture, but the 

end of World War II brought rapid urbanization of 

Omaha and its suburbs (U.S. Army Corps of Engineers, 1967b). A 1957 map of Omaha shows little 

development west of Little Papillion Creek, whereas in 

1990 development was bordering West Papillion 

Creek (fig. 8). By 2000, Omaha had expanded west 

past West Papillion Creek. This urbanization also was 

reflected in the population of Douglas and Sarpy 

Counties, which doubled between 1940 and 1990 

(Forstall, 1995).

Urbanization probably altered the streamflow 

and sediment-load characteristics of the streams, 

which might have disturbed their streambeds. While 

the land was being developed, increased erosion from 

construction projects would have increased the 

sediment supply in the streams and led to aggradation. 

Once development ceased, the land would have 

become more impermeable, leading to greater runoff 

and causing degradation through erosion processes. 

Urbanization was the likely cause of streambed-elevation changes observed at site PC-H on West Papillion 

Creek (fig. 10), and it probably affected many of the 

other sites because urbanization encroached upon most 

of the streams in the basin. 

December 6, 1952

July 6, 1998

1900

295

296

297

298

299

ELEVATION, IN METERS ABOVE 

NGVD OF 1929

1920 1940 1960 1980 2000

Figure 9. Looking upstream at W Papillion Cr at US275 

(PC-3). 

Figure 10. Streambed-elevation changes at W Papillion Cr 

at 66th Street (PC-H).
STREAMBED ADJUSTMENT 28

Flood-Control Channel Modifications Since the 1960s

In addition to the effects on streamflow and 

sediment load, another consequence of urbanization in 

the basin was an increase in property damage caused 

by floods, as more development occurred in the flood 

plain. Only 6 percent of the monetary damages 

incurred by a flood in 1948 were classified as urban, 

whereas the urban property damages caused by a 

similar-sized flood in 1959 accounted for over half of 

the total monetary damages (U.S. Army Corps of 

Engineers, 1967b). Increased urban vulnerability led 

to more flood-control projects in the basin, consisting 

of channelization, channel widening, and the construction of several reservoirs. 

The USACE began several projects in the 1960s 

aimed at preventing flooding in the basin. The lower 

reaches of Papillion Creek, from the mouth to a point 

just below site PC-12, were widened and excavated in 

1964. A reach of Little Papillion Creek from the 

mouth to approximately 3 river-kilometers (RKM) 

downstream from site PC-9 was realigned and 

enlarged between 1965 and 1968 (U.S. Army Corps of 

Engineers, 1989). The USACE (1968) stated that the 

bed was lowered, which included the lowering of the 

grade-control structure downstream from site PC-K. 

As part of these flood-control projects, the USACE 

made plans for a system of six reservoirs in the basin, 

of which five have been built. In addition to providing 

flood protection, these structures also have provided 

grade control on the streams. This occurred at PC-F 

(fig. 11; table 8), where degradation could have 

continued had it not been for the completion of one of 

these structures downstream in the mid-1980s, which 

created backwater conditions at the site and removed 

the erosive energy of the stream.

In addition to the work completed by the 

USACE, the Papio-Missouri River Natural Resources 

District (PMNRD) also completed flood-control 

channel modifications. Part of these modifications 

involved the widening and addition of levees to both 

Big Papillion Creek and West Papillion Creek (fig. 12) 

(Papio-Missouri River Natural Resources District, 

2000). The work began in the late 1960s and continued 

in various segments through the year 2000 (Marlin 

Petermann, Papio-Missouri River Natural Resources 

District, oral commun., 2000). This work may not 

have disturbed the streambed, but it is possible that the 

change to the hydraulic characteristics of the channels 

may lead to gradation change.

Degradation of the Missouri River

Chen and others (1999) found that the MWSE 

of the Missouri River at Omaha dropped nearly 2 m 

between 1936 and 1952. This change may have 

affected Papillion Creek, whose confluence with the 

Missouri River is just downstream from the site 

studied by Chen and others (1999). 

Streambed Summaries

Degradation of more than 1 m was observed at 

14 of the 25 Papillion Creek Basin sites (table 8). 

Degradation since 1910 was estimated along the lower 

reaches of the main stem by using the 2.4 m of degradation that had been documented at PC-J by 1942 

(U.S. Army Corps of Engineers, 1967b). It was 

1900 1920 1940 1960 1980 2000

329

330

331

332

333

ELEVATION, IN METERS ABOVE 

NGVD OF 1929

Figure 11. Streambed-elevation changes at Wehrspann 

Cr at N370 (PC-F).

Figure 12. Channel and levee construction, Big Papillion 

Creek (photograph from the Papio-Missouri River Natural 

Resources District).
29 Streambed Adjustment and Channel Widening in Eastern Nebraska

assumed that the same amount of degradation had 

occurred at the two main-stem sites (PC-M and PC-12) 

downstream. By this method, the 1910 bed elevations 

at sites PC-J, PC-M, and PC-12 were estimated 

(fig. 13; table 8). These streambed-elevation changes 

were probably the result of both the original straightening in the Papillion Creek Basin and the changes to 

the MWSE of the Missouri River. This degradation 

undoubtedly migrated upstream, leading to channel 

incision and the subsequent construction of gradecontrol structures. 

On the North Branch West Papillion Creek, the 

streambed-elevation data (table 8) did not match the 

channel incision observed at sites PC-1 and PC-2, but 

physical measurements of the cohesive strength of the 

streambed at multiple points led Langendoen and

Table 8. Streambed summaries for sites in the Papillion Creek Basin

[ID, identification; RKM, river distance (in kilometers from the mouth); n, number of streambed elevation points used; ∆E, difference in streambed elevation 

between first and last streambed-elevation points, in meters; d50, median streambed grain-size diameter, in millimeters; SICL, silty clay loam; S, sand; SL, 

sandy loam; L, loam; CL, clay loam; SIL, silt loam; --, not available]

Site ID RKM n ∆E

(m)

First 

year

Last 

year

d50

(mm)

Textural 

class Comments

PC-1 44.3 7 –0.2 1957 1998 0.02 SICL

PC-2 39.9 7 –0.4 1957 1999 0.61 S

PC-A 37.7 4 –1.4 1957 1999 -- --

PC-B 37.0 4 –2.0 1957 1999 -- --

PC-C 36.0 4 –2.6 1957 1999 -- --

PC-3 34.1 8 –5.2 1952 1999 0.55 SL Removal/failure of grade-control structure occurred 

between 1952 and 1957.

PC-D 29.6 6 0.0 1957 1999 -- --

PC-E 31.5 3 –0.1 1957 1992 -- -- Streambed is maintained by grade-control structure.

PC-F 34.5 3 –2.4 1957 1989 -- -- Reservoir-induced backwater has occurred since the 

mid-1980s.

PC-G 27.8 2 –0.5 1957 1967 -- --

PC-4 28.1 4 –1.9 1960 1999 0.05 L

PC-5 24.6 27 –1.9 1948 1999 0.04 L

PC-H 17.8 6 0.2 1956 1999 -- --

PC-6 46.7 4 –0.8 1956 1986 0.03 CL

PC-I 44.7 3 –1.4 1956 1990 -- --

PC-7 36.5 16 –1.5 1956 1999 -- --

PC-8 34.7 4 –0.7 1979 1999 0.03 L

PC-J 25.0 5 –3.7 1910 1993 -- -- Most of the degradation was based on the estimate of 

1910 streambed elevation.

PC-9 25.0 31 –0.6 1950 1993 0.09 SL

PC-10 32.9 4 –1.4 1967 1999 0.58 SL Streambed is maintained by grade-control structure.

0.02 SICL Sampled at a clay riffle 85-m downstream of culvert.

PC-11 29.9 3 –0.5 1967 1997 0.88 S Streambed is maintained by grade-control structure.

PC-K 24.1 5 –2.2 1956 1993 -- --

PC-L 22.8 4 –0.6 1956 1993 -- --

PC-M 16.2 5 –2.1 1910 1994 -- -- Most of the degradation was based on the estimate of 

1910 streambed elevation.

PC-12 8.9 33 –4.0 1910 1993 0.03 SIL Most of the degradation was based on the estimate of 

1910 streambed elevation.
STREAMBED ADJUSTMENT 30

Simon (2000) to conclude that the resistance to degradation may increase with distance upstream in this 

area. Although the streambed particle size observed at 

PC-2 was sand (table 8), many hardpan clay riffles 

were observed at the site as well. 

Platte River Tributary Basins

Seven minor tributary basins to the Platte River 

were studied for streambed-elevation changes: Shell 

Creek, Bone Creek, Skull Creek, Otoe Creek, Buffalo 

Creek, Springfield Creek, and Fourmile Creek Basins 

(fig. 14). 

Documented Disturbances, Knickpoints, and 

Grade-Control Structures

All of the basins analyzed had local straightening of the individual streams in the Platte River 

flood plain. Three of the seven basins (Skull, Otoe, and 

Fourmile Creek Basins) also had basinwide straightening of the main stems of the streams. 

Straightening in the Platte River Flood Plain

Local drainage districts and individual landowners straightened reaches of streams lying in the 

Platte River flood plain (fig. 14). Although no 

drainage plans were available, the districts that may 

have straightened reaches of the Platte River tributaries studied here were formed between the early 

1900s and the 1930s (table 9) (Nebraska Department 

of Roads and Irrigation, 1954). Reaches of Springfield 

Creek and Fourmile Creek in the Platte River flood 

plain also were straightened, based on maps of the 

area, although the dates of these efforts are unknown. 

A knickpoint was observed in the Buffalo Creek 

watershed in 1999, and channel incision led to the 

construction of 10 grade-stabilization structures 

throughout the basin in 1991 (Nebraska Natural 

Resources Commission, 1998). Another knickpoint 

was observed on Fourmile Creek just below PRT-12 in 

1998, where rock riprap had been placed in the 

streambed to prevent upstream migration.

Basinwide Straightening

Three of the seven tributary basins studied have 

been straightened throughout most of the reaches of 

their main-stem streams. Frequent flooding of Skull 

Creek led to the channelization of nearly the entire 

drainage network by local interests from the early 

1900s through 1946 (U.S. Army Corps of Engineers, 

1965). Although the channelization of Otoe Creek and 

Fourmile Creek was not documented completely, it 

was identified by the lack of meanders in aerial photographs, and approximate time frames of the work were 

isolated using sets of aerial photographs of various 

dates. Based on these photographs, Otoe Creek was 

straightened before 1949, and Fourmile Creek was 

straightened before 1941. 

In response to streambed degradation on Skull 

Creek (fig. 15), at least five grade-control structures 

have been built (fig. 16). The installation date of these 

structures is unknown, but they appear to be recent 

(probably installed no earlier than 1990). Additionally, 

at a bridge over Skull Creek 1.6 RKM upstream from 

site PRT-5, a series of knickpoints (one of which had a 

0.8-m vertical drop) were observed in September 1998 

that had exposed the footings of the bridge piers. 

When the bridge was revisited in December 1998, all 

of the knickpoints had been inundated by construction 

of a structure similar to the one at site PRT-5 (fig. 16).

Straightening at PRT-3

Following a flash flood that occurred in 1963, a 

short reach of Bone Creek from just above PRT-3 to 

about 0.8 km below the site was straightened. No 

knickpoints were observed at the site, but because no 

sites are farther upstream, it is unknown if a degradation response is migrating upstream. 

Figure 13. Streambed-elevation changes at Big Papillion 

Cr at Cornhusker Rd (PC-M).

1900

294

295

296

297

298

ELEVATION, IN METERS ABOVE 

NGVD OF 1929

1920 1940 1960 1980 2000
31 Streambed Adjustment and Channel Widening in Eastern Nebraska PRT-1 PRT-2 PRT-6 PRT-4 PRT-7 PRT-8 PRT-5 PRT-3

 PRT-9

 PRT-11

 PRT-10

COLUMBUS

LOUISVILLE

NORTH BEND

ASHLAND

DUNCAN

97

 ̊

30'

97

 ̊

96

 ̊

30'

41

 ̊

41

 ̊

30'

Nebraska

Location map

Study area

Study basins 

0 5 10 MILES

0 5 10 KILOMETERS

Base from U.S. Geological Survey1:100,000 digital dataAlbers Equal-Area Conic projectionStandard parallels 29 ̊30' and 45 ̊30'

central meridian -96 ̊00'

Straightening in the Platte River flood plain

Basinwide straightening

Grade-control structures

EXPLANATION

Basin boundaryPrimary study site and identification TownKnickpointsStream

 PRT-10

Platte

River

Shell Creek

Bone Creek

Skull Creek

Otoe Creek

Buffalo Creek

Spr

Figure 14. Location of Platte River Tributary Basins and associated study sites in Nebraska.
32 Streambed Adjustment and Channel Widening in Eastern Nebraska

Streambed Summaries

The magnitude of degradation was greater in the 

three basins that had undergone basinwide straightening than in the other four basins that had only been 

straightened in the flood plain of the Platte River 

(table 10). In the three basins that were affected by 

both Platte River flood plain and basinwide straightening, most of the individual streambed data sets were 

not extensive enough to isolate changes caused by 

flood-plain straightening from those caused by basinwide straightening. However, at site PRT-7, enough 

data exist that two episodes of degradation can be 

identified for the 4.1 m of degradation there (fig. 17) 

(table 10). The 3.2 m of degradation that occurred 

between 1938 and 1995 (0.06 m/yr (meters per year)) 

was assumed to be the result of basinwide straightening that occurred prior to 1949. The 0.9 m of degradation between 1995 and 1999 (0.23 m/yr) was 

probably the result of the headward progression of the 

disturbance caused by straightening of Otoe Creek in 

the flood plain around 1930. This would mean the 

knickpoint took almost 60 years to migrate 9.5 RKM. 

In the four basins where straightening only 

occurred in the Platte River flood plain, degradation 

probably migrated upstream, although some of the 

streambeds did not degrade much (table 10). For 

example, the channel near site PRT-4 was straightened 

around 1941 (based on aerial photographs and bridge 

plans), but the streambed had degraded 0.4 m by 1993. 

Chen and others (1999) found no significant change in 

the MWSE at site PRT-1. The data at sites PRT-9 and 

PRT-11 were not extensive enough to show streambedelevation changes, but the channels at both sites and at 

other bridges over Buffalo and Springfield Creeks 

were deeply incised with no visible streambed deposition and numerous vertical faces on the streambanks. 

Not enough data were available at sites PRT-8 

and PRT-13 to identify streambed-elevation changes. 

Both sites are affected by backwater from the Platte 

River. The change observed at PRT-3 was probably the 

result of localized straightening at the site in 1963. 

Table 9. Drainage districts associated with selected Platte River tributaries

Drainage district name Streams that may have been 

straightened

Date drainage plans were 

approved

Butler County Drainage District No. 1 Bone Creek or Skull Creek August 5, 1918

Butler County Drainage District No. 2 Bone Creek or Skull Creek July 26, 1917

Platte Valley Drainage District Shell Creek December 28, 1920

Leshara Drainage District Otoe Creek September 18, 1930

South Buffalo Creek Drainage District Buffalo Creek May 25, 1926

1900

426

427

428

429

430

431

432

ELEVATION, IN METERS ABOVE 

NGVD OF 1929

1920 1940 1960 1980 2000

Figure 15. Streambed-elevation changes at Skull Creek 

at Butler County road (PRT-5).

Figure 16. Looking downstream at grade-control structure 

on Skull Creek at PRT-5.
33 Streambed Adjustment and Channel Widening in Eastern Nebraska

Elkhorn River Basin

Over a period of 50 years, several reaches of the 

Elkhorn River and some of its tributaries have been 

straightened by at least 15 different entities, which has 

led to channel instability in the Elkhorn River Basin. 

Because the Elkhorn River Basin extends west beyond 

the study area and into the Nebraska Sandhills, only 

streams in the eastern part of the basin were studied 

(fig. 18). This means that a larger supply of sand is in 

the Elkhorn River main stem than in other streams of 

the eastern part of the basin or of the remainder of the 

study area. As the Elkhorn River was straightened, the 

magnitude of the degradation response probably was 

reduced by the sand supply available. 

Table 10. Streambed summaries for sites in the Platte River Tributary Basins

[ID, identification; RKM, river distance (in kilometers from the mouth); n, number of streambed elevation points used; ∆E, difference in streambed 

elevation between first and last streambed-elevation points, in meters; d50, median streambed grain-size diameter, in millimeters; SL, sandy loam; S, 

sand; SIL, silt loam; SICL, silty clay loam; L, loam; --, not available]

Site ID RKM n ∆E

(m)

First 

year

Last 

year

d50

(mm)

Textural 

class Comments

Shell Creek Basin

PRT-1 53.4 25 0.3 1947 1999 0.22 SL None

PRT-2 8.6 7 –0.8 1957 1998 0.47 S None

Bone Creek Basin

PRT-3 31.0 17 –1.4 1963 1999 0.03 SIL None

PRT-4 17.5 7 –0.9 1941 1998 0.03 SIL None

Skull Creek Basin

PRT-5 25.6 4 –3.1 1963 1997 0.02 SICL None

PRT-6 14.9 6 –1.0 1963 1999 0.70 SL None

Otoe Creek Basin

PRT-7 9.5 7 –4.1 1938 1999 0.02 SICL None

PRT-8 1.6 4 –0.6 1976 1999 0.05 L None

Buffalo Creek Basin

PRT-9 12.3 2 0.0 1998 1999 0.03 SIL None

PRT-10 1.8 6 –0.2 1951 1999 0.70 S None

Springfield Creek Basin

PRT-11 6.2 6 –0.6 1976 1999 0.03 SIL None

Fourmile Creek Basin

PRT-12 8.3 4 –3.0 1949 1999 0.02 SIL None

PRT-13 1.5 2 –1.4 1980 1998 -- -- None

1900 1920 1940 1960 1980 2000

368

369

370

371

372

373

374

ELEVATION, IN METERS ABOVE 

NGVD OF 1929

Figure 17. Streambed-elevation changes at Otoe Cr at 

US77 (PRT-7).
STREAMBED ADJUSTMENT 34

 10 ER-

 11 ER- 13 ER-

 ER-12

 4 ER- 14 ER-

 1 ER-

 5 ER-

 3 ER-

 6 ER- 2 ER- ER-7

 ER- 22

 16 ER- ER- 18 

ER-15

 8 ER-

 ER- 9

ER- 19

 17 ER- 20 ER-

 ER-21 ER- 23

 ER- 24

 25 ERNORFOLK

WEST POINT

CONCORD

MADISON

S

Little Bell Creek

Humbug Cree

El

k

khorn River

Elkhorn River

Union Creek

W Fork Maple Creek

E

Fork Maple Creek

Maple Creek

Rawhide Creek

Elkhorn River

Pebble Creek

Elkhorn River

Plum Creek

Logan Creek

Logan Creek

Log

D

an Creek eer Cree k

Middle Logan Creek

Dry Creek

Bell Creek

42 ̊

42 ̊30'

97 ̊30'

96 ̊30'

41 ̊30'

97 ̊

Nebraska

Location map

Study area

Study

basin 

0 5 10 MILES

0 5 10 KILOMETERS

EXPLANATION

Basin boundary

Primary study site and identification 

Town

Knickpoints

Stream

Elkhorn River straightening

ER-2

Grade-control structures

Maple Creek straightening

Logan Creek straightening

Straightening on other tributaries

Base from U.S. Geological Survey

1:100,000 digital data

Albers Equal-Area Conic projection

Standard parallels 29 ̊30' and 45 ̊30'

central meridian -96 ̊00'

Figure 18. Eastern part of the Elkhorn River Basin and associated study sites in Nebraska.
STREAMBED ADJUSTMENT 35

Documented Disturbances, Knickpoints, and 

Grade-Control Structures

Population growth in the Elkhorn River Basin in 

the late 1800s and early 1900s led to a greater need for 

flood protection (Kerstetter, 1992). As a result, several 

drainage districts were created (table 11) to straighten 

stream reaches. Additionally, aerial photographs show 

several more stream reaches that were straightened. 

Because so many individual straightening efforts 

occurred in this basin, discussions in this section of the 

report are grouped by stream system.

Straightening of the Elkhorn River

Three reaches of the Elkhorn River have been 

straightened (table 11). First, the lower 32 RKM of the 

Elkhorn River was straightened in 1914 (Kerstetter, 

1992). Next, a short reach of the river near Norfolk 

was straightened in 1924. Then, between 1949 and 

1952, meanders were removed from a 105 RKM-long 

reach of the river (fig. 18), changing the stream 

gradient in that reach from 0.0026 m/m to 0.0040 m/m 

(Bentall, 1971). 

Straightening of Logan Creek

Nearly the entire length of Logan Creek was 

straightened, as well as its north and south branches 

(table 11). Eight separate drainage districts completed 

the work between 1917 and 1926 (Kerstetter, 1992). In 

some cases, the dimensions of the channel were not 

uniform between districts. For example, whereas the 

Oakland Drainage District called for a 3.2-m-deep 

channel at its upstream end, the Wakefield Drainage 

District designed a 4.6-m-deep channel approximately 

67 RKM upstream from the Oakland Drainage 

District. The cumulative effect of these districts on 

Logan Creek was a stream gradient that went from 

0.0003 m/m in its natural state to 0.0006 m/m in its 

straightened state (Bentall, 1971). 

This straightening led to streambed degradation 

on Logan Creek and its tributaries. At site ER-12, a

Table 11. Drainage districts associated with the Elkhorn River Basin

[NA, not available]

Drainage district name Streams that may have been straightened Date drainage plans 

were approved

Elkhorn River Drainage District1 Elkhorn River-lower 32 river kilometers1 1 1914

NA Rawhide Creek1 1 Before 1911

NA Logan Creek-Uehling, Nebraska area 1 1917–1926

Oakland Drainage District Logan Creek-Oakland, Nebraska area 1 1917–1926

Lyons Drainage District2 Logan Creek-Lyons, Nebraska area 1 1917–1926

NA Logan Creek-Pender, Nebraska area 3 1918

Pender Drainage District2 Logan Creek, Rattlesnake Creek-Pender, Nebraska area 2 February 28, 1951

Wakefield Drainage District2 Logan Creek-Wakefield, Nebraska area 2 January 18, 1917

North and South Logan Drainage District2 North Logan Creek and South Logan Creek 2 February 17, 1925

Laurel Drainage District2 Middle Logan Creek 2 December 15, 1925

Humbug Drainage District2 Humbug Creek 2 March 15, 1921

Norfolk Drainage District2 Elkhorn River-Norfolk, Nebraska area1 2 March 18, 1924

Bell Creek Drainage District2 Bell Creek 2 January 13, 1947

West Maple Creek Drainage District4 Maple Creek-upstream from site ER-195 4 1960

NA Elkhorn River-South border of Cuming County to Stanton, 

Nebraska6

6 1949–1952

U.S. Army Corps of Engineers Union Creek-Madison, Nebraska area7 7 1965–1966

1 From Kerstetter, 1992.

2 From Nebraska Department of Roads and Irrigation, 1954.

3 From U.S. Army Corps of Engineers, 1993.

4 From Soil Conservation Service, 1971.

5 From aerial photographs on file at the Conservation and Survey Division of the University of Nebraska-Lincoln. 6 From Bentall, 1971.

7 From U.S. Army Corps of Engineers, 1980.
STREAMBED ADJUSTMENT 36

drop structure was constructed in the 1990s in 

response to a large knickpoint that had migrated 

upstream through the bridge location (fig. 19). Several 

more knickpoints were observed in 1998 just downstream from that bridge. Unless it fails, this structure 

will halt the progress of degradation farther upstream 

into the South Logan Creek subbasin, thereby 

guarding site ER-11. Another knickpoint was 

observed approximately 25 RKM downstream from 

ER-10 on Middle Logan Creek near the town of 

Concord, Nebraska, in 1998 (U.S. Army Corps of 

Engineers, 1998). 

Straightening of Maple Creek

In June 1944, the most damaging flood up to 

that time struck the Elkhorn River Basin. The Maple 

Creek Subbasin experienced the most severe flooding 

where the peak flow at site ER-21 exceeded the 

500-year recurrence interval (Soenksen and others, 

1999). To guard against future flooding, a drainage 

district was organized to straighten Maple Creek 

upstream from ER-19 (table 11). Aerial photography 

indicates that several other stream reaches also were 

straightened, including the main stem of Maple Creek 

downstream from site ER-19, most of East Fork Maple 

Creek, and some of West Fork Maple Creek (fig. 18).

This straightening probably led to a channel 

response in the Maple Creek Subbasin. Field observations at bridges downstream from ER-18 and ER-16 

show incised channels with vertical cut-banks and no 

deposition, including one where a knickpoint with a 

0.9-m water-surface drop was present in 1999 

(fig. 20). Although there is some rock riprap around it, 

if this knickpoint migrates upstream, it will eventually 

cause degradation at site ER-18.

Straightening of Other Elkhorn River Tributaries

Other streams in the basin also were straightened. Drainage districts or the USACE performed 

channel modifications on Rawhide Creek (before 

1911), Humbug Creek (in 1921), Bell Creek (in 1947), 

and Union Creek (in 1966) (table 11). Aerial 

photography revealed several other stream reaches that 

were straightened. Based on these photographs, Dry 

Creek, the lower reaches of Pebble Creek, and the 

upper reaches of Plum Creek were straightened sometime prior to 1938. Photographs from 1949 showed 

straightening in the upper reaches of Pebble Creek and 

its tributaries and the lower reaches of Plum Creek 

(fig. 18).

Streambed Summaries

Streambed-elevation changes to the Elkhorn 

River varied. ER-1 and ER-25 both show 1.1 to 1.4 m 

of degradation while ER-6 shows a small amount of 

aggradation (table 12). It is possible that the degradation at ER-25 was in response to the straightening of 

the lower reaches of the river in 1914, whereas the 

degradation of ER-1 was caused by the straightening 

that took place in 1924 and 1949–52, thereby 

increasing the sediment load to ER-6. The streambeds 

at all three sites are dominated by sand (table 12).

When available, construction plans for Logan 

Creek were used to estimate streambed elevations 

following the straightening work done between 1917 

and 1926. This straightening led to the degradation

Figure 19. Drop structure at S Logan Cr at N15 (ER-12). Figure 20. Knickpoint on East Fork Maple Creek located at 

SW1/4 sec. 26, T. 19 N., R. 4 E.
STREAMBED ADJUSTMENT 37

observed at sites ER-12, ER-13, ER-14, and ER-15 

(fig. 21; table 12). Degradation at site ER-12 since 

1990 is likely the result of local scour effects below 

the grade-control structure. This structure will guard 

against future degradation upstream from site ER-12, 

including at ER-11, which showed little gradation 

change from 1936 to 1997. 

The Maple Creek modifications also affected its 

streambed (table 12). Degradation occurred between 

1925 and 1960 at site ER-21, but aggradation has 

occurred since 1960. The data at sites ER-19 and 

ER-20 were not extensive enough to show streambedelevation responses, although point bars were 

observed at both sites, indicating that they might also 

be aggrading. Although ER-16 and ER-18 showed 

little gradation change, the presence of incised channels and knickpoints farther downstream indicate that 

degradation may be migrating upstream to the sites.

Table 12. Streambed summaries for sites in the Elkhorn River Basin

[ID, identification; RKM, river distance (in kilometers from the mouth); n, number of streambed-elevation points used; ∆E, difference in streambedelevation between first and last streambed-elevation points, in meters; d50, median streambed grain-size diameter, in millimeters; S, sand; SIL, silt 

loam; SICL, silty clay loam; SIC, silty clay; SL, sandy loam; LS, loamy sand; --, not available]

Site ID RKM n ∆E

(m)

First 

year

Last 

year

d50

(mm)

Textural 

class Comments

ER-1 208.3 25 –1.1 1945 1997 0.32 S

ER-2 233.2 12 –0.9 1965 1998 0.023 SIL

ER-3 195.4 1 -- 1998 1998 0.32 S

ER-4 185.9 3 –0.7 1937 1999 0.031 SIL

ER-5 157.4 5 –2.0 1962 1999 0.017 SICL

ER-6 129.5 19 0.4 1953 1999 0.32 S

ER-7 156.5 4 –0.8 1973 1999 0.032 SIL

ER-8 121.7 4 –0.8 1946 1999 0.016 SIC

ER-9 104.8 11 –0.5 1978 1999 0.20 SL

ER-10 225.3 5 0.4 1945 1999 0.14 SL

ER-11 219.2 4 0.2 1936 1997 0.022 SICL

ER-12 198.2 4 –3.2 1967 1998 0.024 SIL Grade control structure at the site.

ER-13 180.2 5 –2.3 1918 1997 0.73 S Most of the degradation was based on 

the estimate of 1918 streambed 

elevation.

ER-14 154.2 17 –3.1 1919 1999 0.48 S Most of the degradation was based on 

the estimate of 1919 streambed 

elevation.

ER-15 94.3 29 –2.3 1917 1999 0.32 S Most of the degradation was based on 

the estimate of 1917 streambed

elevation.

ER-16 151.9 4 0.0 1951 1999 0.030 SIL

ER-17 136.6 5 –0.7 1957 1999 0.027 SIL

ER-18 140.8 6 –0.7 1950 1999 0.019 SICL

ER-19 103.4 4 –1.0 1968 1998 0.38 S

ER-20 79.2 8 –1.4 1966 1999 0.46 S

ER-21 75.2 31 –0.5 1925 1996 0.25 S

ER-22 93.7 4 –1.2 1946 1999 0.016 SICL

ER-23 57.0 3 –0.5 1964 1999 0.027 SIL

ER-24 56.3 3 –0.4 1947 1998 0.030 SIL The 1947 streambed elevation was 

estimated.

ER-25 22.3 48 –1.4 1928 1996 0.15 LS
STREAMBED ADJUSTMENT 38

Little data were available at the Pebble Creek 

and Plum Creek sites, although the data at all of these 

sites showed at least some degradation, and field 

reconnaissance of these streams revealed many incised 

channels. Modifications to Bell Creek in 1947 likely 

led to the degradation observed at all three sites in the 

Bell Creek subbasin. The sites on Union Creek did not 

appear to have been affected by the straightening of 

the creek that occurred in 1966. 

Salt Creek Basin

Several disturbances to different reaches of the 

Salt Creek Basin have occurred that have greatly 

affected some streams in the basin, while leaving 

others relatively undisturbed. The original modifications to Salt Creek and its tributaries in the Lincoln 

area (fig. 22) occurred in the late 1800s. The rest of 

Salt Creek downstream from Lincoln was straightened 

by cutting off meanders between 1917 and 1941 

(Farrar and Gersib, 1991). In addition, individual 

reaches of several tributaries were straightened, 

although the time period and source of such work was 

not available. Streams in the Lincoln area also were 

affected by a combination of urbanization and floodcontrol projects in the 1960s. 

Documented Disturbances, Knickpoints, and 

Grade-Control Structures

Original Channelization of Salt Creek

The original channelization of Salt Creek 

directly affected the main stem from its confluence 

with the Platte River upstream through the city of 

Lincoln. Work began in 1891, when the Lancaster 

County Sanitary District Number 1 was organized 

(Farrar and Gersib, 1991). Initial straightening and 

widening was completed on Salt Creek only in the area 

around Lincoln and parts of its tributaries, including 

the lower 0.8 km of Haines Branch, the lower 3.2 km 

of Middle Creek, the lower 6.4 km of Oak Creek 

(Farrar and Gersib, 1991), and the lower parts of Little 

Salt Creek, and Stevens Creek (U.S. Army Corps of 

Engineers, 1967a). Construction plans from this work 

in Lincoln indicated that Salt Creek would be 

constructed to an average channel depth of 4.9 m (the 

pre-modified depth at one location was 2.6 m) and an 

average channel width of 30.5 m (Brook and others, 

1892). These plans were used to determine that about 

3.5 m of degradation occurred at SC-13 following 

channelization (fig. 23).

A USGS flood measurement done in 1953 at 

SC-7 also provided historical information on the 

channel, which was constructed in 1917. Since 

construction, the channel at SC-7 has deepened by 4 m 

and undergone significant channel enlargement 

(fig. 24).

The reach of Salt Creek between Lincoln and 

the mouth near Ashland was straightened from 1917 

to 1942, with most of the work occurring in the 1930s 

(Farrar and Gersib, 1991). The reach was straightened 

by cutting off meanders, and the overall slope of the 

stream increased. Although the straightening of Salt 

Creek extended beyond the borders of Lancaster 

County, the only documented drainage district in 

the basin was Lancaster County Sanitary District 

Number 1. At the lower end of the straightened work 

near Ashland, a bedrock outcrop served as a local 

grade control just downstream from SC-X until 1964, 

when the channel eroded around it. 

Just below the confluence of Rock Creek with 

Salt Creek, at site SC-26, an estimated 2.0 m of degradation occurred from 1935 to 1983. A knickpoint from 

this disturbance likely migrated upstream into Rock 

Creek, leading to the degradation seen at site SC-V. 

However, the degradation exposed an outcrop of frac1900 1920 1940 1960 1980 2000

367

368

369

370

371

ELEVATION, IN METERS ABOVE 

NGVD OF 1929

Figure 21. Streambed-elevation changes at Logan Cr at 

Dodge County Road 22 (ER-15).
39 Streambed Adjustment and Channel Widening in Eastern Nebraska

 SC-31

 32 SC-

 29 SC-

 27 SC- 30 SC-

 W SC-

 28 SC-

 33 SC- 34 SC-

 9 SC- 10 SC-

 X SC- 24 SC-

 P SC-

 N SC- O SC-

 Q SC-

 25 SC-

 R SC-

 17 SC-

 14 SC-

 S SC-

 15 SC-

 18 SC-

 T SC-

 16 SC-

 U SC-

 V SC-

 19 SC- 26 SC-

 20 SC-

 21 SC- 12 SC-

 22 SCSC-11

 23 SC-

 13 SC-

 7 SC-

 6 SC-

 8 SC-

 M SC-

 L SC-

 J SC-

 I SC-

 H SC-

 G SC-

 4 SC- SC-F E SC-

 D SC-

 C SC-

 B SC-

 A SC-

 K SC-

 5 SC-

 3 SC-

 2 SC-

 1 SCASHLAND

WAHOO

LINCOLN

 

Cottonwood Creek

Sand Creek

N. Fork Wahoo Cre ek

Rock Creek

Little Salt

N. Oak

Creek

Oak

Creek

Deer Creek

W. Oak Creek

Creek

So. Br. Middle Cr Middle Creek

Haines Branch

Salt Creek

Beal Slough

Stevens Creek

Hickman Br

Olive Br

Salt Creek

Wahoo Creek

Clear Creek

Platte River

Johnson Creek

0 5 10 MILES

0 5 10 KILOMETERS

41 ̊15'

96 ̊45'

97 ̊

41 ̊

40 ̊45'

96 ̊30'

Original straightening, 1891–1942

SC-2

SC-B

Tributary straightening

Flood-control modifications, 1960s

Grade-control structures

Base from U.S. Geological Survey

1:100,000 digital data

Albers Equal-Area Conic projection

Standard parallels 29 ̊30' and 45 ̊30'

central meridian -96 ̊00'

Location map

Nebraska

Study area

Study

basin 

EXPLANATION

Basin boundary

Primary study site and identification 

Supplemental study site and identification 

Town

Knickpoints

Stream

Figure 22. Location of Salt Creek Basin and associated study sites in Nebraska.
STREAMBED ADJUSTMENT 40

tured Dakota sandstone between sites SC-V and SC-U that 

was observed in 1969 during a discharge measurement. An 

inadvertent grade-control structure was created on Rock 

Creek with the 1982 construction of a pipeline crossing 4.8 

RKM upstream from the mouth, which was protected by 

grout pillows and armoring in 1987 (Natural Resources 

Conservation Service, 1996a). Additionally, two gradecontrol structures upstream from site SC-P and downstream 

from site SC-O were installed in the 1990s to prevent 

channel incision into the saline wetlands of the subbasin 

(Natural Resources Conservation Service, 1996a).

A grade-control structure has been in place on 

Stevens Creek near its mouth since at least 1965 

(U.S. Army Corps of Engineers, 1967a), although 

degradation was observed at SC-23 over the same time 

period. 

On Little Salt Creek, a knickpoint was observed 

at approximately RKM 52.5 (between sites SC-20 and 

SC-21) in 1999. Although the knickpoint could eventually migrate upstream into the rest of the subbasin, 

the streambed there was protected by cobbles in 1999, 

which served as grade protection. The Little Salt 

Creek Subbasin also benefits from a low-head dam 2.2 

RKM upstream from site SC-21, which may prevent 

future knickpoints from migrating upstream from it. 

Individual Tributary Modifications

Although the original straightening of Salt 

Creek led to a response that could have affected the 

entire basin, the modifications to some Salt Creek tributaries created additional responses that were specific 

to the corresponding subbasins. In some cases, organized drainage districts did this work, and in others it 

was probably the cumulative efforts of individual landowners. The tributary subbasins studied that appeared 

to have been modified were Wahoo Creek, Rock 

Creek, Oak Creek, and Beal Slough. A reach of Salt 

Creek upstream from Lincoln (fig. 22) also was 

modified. Other tributaries were modified but were not 

analyzed for this study.

The stream-channel modifications in the Wahoo 

Creek Subbasin were not uniform along the tributary 

streams. Although the changes to Wahoo Creek and 

Cottonwood Creek were fairly localized, almost all of 

the tributary subbasins of Clear Creek and Sand Creek 

were straightened. The Clear Creek Drainage District 

straightened most of Clear Creek between 1925 and 

1930 (Nebraska Department of Roads and Irrigation, 

1954). Aerial photographs indicated that nearly the 

entire length of Sand Creek was straightened by 1955, 

which likely led to a response that migrated upstream 

through the subbasin. This work was probably the 

cause of the knickpoint (3.4-m drop in water surface 

over a 25.4-m distance) observed in 1997 at site SC-31 

on a small, unnamed tributary (fig. 25). Although no 

historical data were available with which it could be 

compared, 1.1 m of degradation was observed at one 

point along this knickpoint between the first round of 

surveying in 1997 and the second round in 1999.

1900 1920 1940 1960 1980 2000

339

340

341

342

343

344

345

ELEVATION, IN METERS ABOVE 

NGVD OF 1929

355

0 10 20 30 40 50 60

357

359

361

363

365

ELEVATION, IN METERS ABOVE 

NGVD OF 1929

1917

1940

1953

1997

DISTANCE, IN METERS

Figure 23. Streambed-elevation changes at Salt Cr at 

N 27th St, Lincoln (SC-13).

Figure 24. Stream channel response at Middle Cr at US6 

(SC-7) following 1917 straightening.
41 Streambed Adjustment and Channel Widening in Eastern Nebraska

Aerial photographs indicated straightening of 

several reaches of Rock Creek between 1940 and 

1971. This work consisted mainly of meander cutoffs 

and occurred over an extended period of time. 

Although the lower 6.4 km of Oak Creek was 

modified between 1909 and 1913, the straightened 

reach was extended upstream, to site SC-11 in the 

mid-1940s (Farrar and Gersib, 1991). Three weirs 

were installed on the lower reaches of Oak Creek 

(below site SC-11), which were built sometime prior 

to 1961 (U.S. Army Corps of Engineers, 1967a). 

Additionally, the USACE built a dam on Oak Creek at 

RKM 94 in the mid-1960s (Farrar and Gersib, 1991).

Local straightening of the lower 3.5 RKM of 

Beal Slough was completed prior to 1940. Although 

no historical data were available to verify it, pictures 

of the channel from 1954 at site SC-F showed a small 

but incised channel, indicating that the straightening 

probably caused some degradation in the subbasin.

Aerial photographs indicate that a short reach of 

Salt Creek just downstream from site SC-3 was 

straightened between 1949 and 1993.

Urbanization and Flood Control Modifications in the 

Lincoln Area

Urbanization altered the streamflow and sediment load delivered to channels in the Lincoln area 

and increased the damage from flooding. According to 

U.S. census data, the population of Lancaster County, 

where Lincoln is located, was 155,000 persons in 

1960, an increase of almost 50 percent over the 1940 

population (Forstall, 1995). The Beal Slough subbasin 

has become particularly developed, growing from 

40-percent urbanized in 1978 to 75-percent urbanized 

in 1997 (Lower Platte South Natural Resources 

District, 1999). This urbanization may have altered the 

amount of sediment delivered to the stream. During 

periods of increased development, erosion from the 

construction zones could have increased sediment load 

in the stream. Once these areas were developed, 

though, the sediment supply was cut off. Additionally, 

the streamflow would have increased in developed 

regions by creating impermeable areas. For example, 

at site SC-F on Beal Slough, a streamflow of 102 m3

/s 

had a 50-year recurrence interval in 1986 but only a 

7-year recurrence interval in 1997 (Lower Platte South 

Natural Resources District, 1999). The decrease in 

sediment supply and increase in streamflow would 

have caused stronger erosional forces to act on the 

stream channels.

Another consequence of urbanization was that 

further modifications were made to Salt Creek and its 

tributaries in the 1960s (U.S. Army Corps of Engineers, 1964). This work consisted mainly of channel 

widening and the addition of levees along the channels, but a few reaches also were straightened, 

including the lower 0.8 RKM of Middle Creek and 

Salt Creek from its confluence with Haines Branch, 

upstream to its confluence with Beal Slough 

(U.S. Army Corps of Engineers, 1963). 

These modifications to the channels around 

Lincoln led to channel responses and, in some cases,

92

93

94

95

96

97

98

STREAMBED ELEVATION, IN METERS 

ABOVE ARBITRARY DATUM

0 50 100 150 200 250 300 400

DISTANCE DOWNSTREAM FROM BRIDGE,

IN METERS

07/17/1997

04/22/1999

A B

Figure 25. (A) Photograph of knickpoint and (B) streambed profile observed at Sand Cr Tributary at Saunders County Road 24 

(SC-31).
STREAMBED ADJUSTMENT 42

subsequent installation of grade-control structures. On 

Haines Branch, a knickpoint that may migrate 

upstream was observed between sites SC-K and SC-5. 

In response to streambed degradation on Beal Slough, 

several grade-control structures have been built, 

including one just upstream from SC-H installed 

sometime after 1995 (fig. 26). Two culverts located 

between SC-G and SC-H also provide grade control. 

Streambed Summaries

Thirty-two of the 58 sites studied in the Salt 

Creek Basin showed degradation greater than 1 m 

(table 13). The presence of bedrock outcrops and other 

grade-control structures added complexity to the 

responses. Because of the many disturbances, sites in 

the basin have likely undergone several episodes of 

streambed gradation. Though some of the site 

responses have been attributed to specific disturbances, data were insufficient at many other sites to 

accurately characterize complex responses.

Streambed degradation caused by the original 

straightening of Salt Creek was computed at SC-13 

(fig. 23) and SC-22 by estimating the constructed

streambed elevation for a 4.9-m deep channel 

(table 13). Both sites show degradation that occurred 

before 1950. Further streambed change has occurred at 

the sites, but it is likely a result of another disturbance, 

such as that caused by urbanization and channel modifications of the 1960s. The streambed elevation change 

observed at SC-X was based on data available at the 

site prior to channel straightening. Since being 

straightened, the streambed there has aggraded.

Most of the channel response that resulted from 

the original channelization probably had progressed 

into the upper reaches of tributaries in the basin by 

1999. Degradation responses were indicated in the 

1960s in the lower reaches of Haines Branch, Little 

Salt Creek (fig. 27), Middle Creek, and Oak Creek 

(table 13). In the Middle Creek and Oak Creek Subbasins, the lower sites have shown degradation whereas 

the upper sites have not yet been affected. 

However, during the same time period, few 

erosion problems were reported for Stevens Creek 

(U.S. Army Corps of Engineers, 1967a). Salt Creek 

had evidently stabilized to channel depths of up to 

7.6 m and widths of up to 45.7 m by 1961 (U.S. Army 

Corps of Engineers, 1963). 

In addition to being used for these analyses, the 

data from these sites also were applied to a channelevolution model to simulate long-term responses in the 

Little Salt Creek Subbasin. Langendoen and Simon 

(2000) describe the CONservational Channel Evolution and Pollutant Transport System (CONCEPTS) 

model and results in detail. The model predicted 4.0 m 

of degradation at RKM 52.5 near site SC-20 and 1.5 m 

of degradation at site SC-19 in the next 60 years 

(Langendoen and Simon, 2000). 

The stream channels at sites on North Fork 

Wahoo Creek (sites SC-27 and SC-28) and Cottonwood Creek (sites SC-29 and SC-30) all were somewhat incised with streambank-failure blocks present. 

However, streambed-elevation data showed no signifi1900 1920 1940 1960 1980 2000 339

340

341

342

343

344

345

ELEVATION, IN METERS ABOVE 

NGVD OF 1929

Figure 26. Grade-control structure on Beal Slough 

upstream from Link 55W (SC-H).

Figure 27. Streambed-elevation changes at Little Salt Cr at 

Arbor Road (SC-21).
43 Streambed Adjustment and Channel Widening in Eastern Nebraska

Table 13. Streambed summaries for sites in the Salt Creek Basin

[ID, identification; RKM, river distance (in kilometers from the mouth); n, number of streambed-elevation points used; ∆E, difference in streambed 

elevation between first and last streambed-elevation points, in meters; d50, median streambed grain-size diameter, in millimeters; SIL, silt loam; SL, 

sandy loam; L, loam, CL, clay loam; SICL, silty clay loam; S, sand; LS, loamy sand; LSIL, loam silt loam; --, not available]

Site ID RKM n ∆E

(m)

First 

year

Last 

year

d50

(mm)

Textural 

class Comments

SC-1 122.8 10 –0.5 1956 1999 0.037 SIL

SC-2 106.1 15 –1.7 1939 1998 0.081 SL

SC-3 87.6 23 –0.6 1951 1998 0.037 L

SC-A 68.9 3 0.8 1961 2000 -- --

SC-B 66.9 3 0.1 1961 2000 -- --

SC-C 65.7 4 0.9 1961 2000 -- --

SC-D 65.7 4 1.0 1961 2000 -- --

SC-E 65.2 4 0.3 1961 2000 -- --

SC-F 64.2 4 –1.5 1961 2000 -- --

SC-4 64.1 7 –1.9 1961 1999 0.026 CL

SC-G 64.0 4 –2.2 1961 2000 -- --

SC-H 60.4 3 –2.6 1961 2000 -- --

SC-I 59.3 3 –2.5 1961 2000 -- --

SC-J 59.2 3 –2.8 1961 2000 -- --

SC-5 78.2 5 –2.4 1939 1999 0.024 SICL A knickpoint is present at the site.

SC-K 77.6 6 –2.2 1939 1999 -- --

SC-L 61.3 2 –0.6 1962 1991 -- --

SC-M 59.3 2 –0.3 1986 1991 -- --

SC-6 79.4 6 –1.1 1940 1999 0.34 S

SC-7 67.1 8 –4.2 1917 1999 0.40 SL

SC-8 62.2 12 –1.2 1940 1999 0.45 LS

SC-9 117.6 4 –0.1 1975 1999 0.52 SL

SC-10 104.8 4 0.9 1975 1999 0.70 S

SC-11 65.9 8 –3.4 1945 1999 0.58 S

SC-12 68.3 7 –1.2 1940 1999 0.32 SL Rock riprap was installed on the 

streambed in 1980s.

SC-13 50.2 23 –4.4 1900 1996 0.65 S Most of the degradation was based on 

the estimate of 1900 streambed 

elevation.

SC-14 64.4 2 0.2 1996 1998 0.049 L

SC-15 62.0 4 –1.8 1975 1999 0.037 SIL

SC-16 61.1 6 –0.6 1939 1999 0.48 SL

SC-17 67.5 3 –0.3 1997 1999 0.049 L

SC-18 63.4 4 –0.9 1975 1999 0.038 SIL

SC-19 58.8 5 –0.5 1939 1998 0.13 L

SC-20 54.0 4 0.1 1978 1999 0.055 L

SC-21 48.4 18 –2.3 1965 1999 0.69 LS
STREAMBED ADJUSTMENT 44

SC-22 41.5 11 –4.9 1910 1999 0.75 S Most of the degradation was based on 

the estimate of 1910 streambed 

elevation.

SC-23 40.1 15 –1.0 1966 1999 0.023 LSIL

SC-24 55.7 9 –0.3 1943 1999 0.054 L

SC-N 51.1 5 –0.7 1938 1994 -- --

SC-O 48.9 5 –0.9 1943 1994 -- --

SC-P 43.5 6 –1.9 1930 1994 -- --

SC-Q 40.9 5 –2.7 1960 1994 -- --

SC-25 38.1 29 –1.7 1967 1996 0.020 SICL

SC-R 36.0 5 –2.3 1930 1994 -- --

SC-S 33.8 7 –1.7 1939 1994 -- --

SC-T 31.5 4 –1.5 1967 1994 -- --

SC-U 28.2 5 –1.4 1960 1994 -- --

SC-V 27.7 6 –2.5 1930 1994 -- --

SC-26 21.0 34 –1.4 1953 1996 0.25 SL

SC-27 87.6 14 –0.5 1953 1999 0.72 LS

SC-28 72.3 17 0.0 1951 1998 0.050 L

SC-29 89.9 3 –0.3 1996 1999 0.35 L

SC-30 70.1 5 –0.2 1986 1998 0.034 L

SC-31 85.2 2 –1.1 1997 1999 0.023 SICL A knickpoint is present at the site.

SC-32 80.8 6 –1.7 1968 1999 0.69 S

SC-W 56.8 3 –1.5 1959 1981 -- --

SC-33 37.5 30 –0.5 1950 1996 0.24 SL

SC-34 16.1 10 –0.3 1979 1999 0.15 SL

SC-X 3.6 15 –4.3 1930 1990 -- -- Most of the degradation was an artifact 

of the 1930 “pre-modified” streambed 

elevation.

Table 13. Streambed summaries for sites in the Salt Creek Basin—Continued

[ID, identification; RKM, river distance (in kilometers from the mouth); n, number of streambed-elevation points used; ∆E, difference in streambed 

elevation between first and last streambed-elevation points, in meters; d50, median streambed grain-size diameter, in millimeters; SIL, silt loam; SL, 

sandy loam; L, loam, CL, clay loam; SICL, silty clay loam; S, sand; LS, loamy sand; LSIL, loam silt loam; --, not available]

Site ID RKM n ∆E

(m)

First 

year

Last 

year

d50

(mm)

Textural 

class Comments

cant degradation over the period of the data (table 13) 

dating back to the 1950s at the North Fork Wahoo 

Creek sites. No significant degradation of Wahoo 

Creek at site SC-33 was apparent until 1967. This 

response may be specific to the site because no other 

sites in the Wahoo Creek Subbasin—upstream or 

downstream from SC-33—showed similar responses.

Analyses at the site in the Clear Creek Subbasin 

(site SC-34) did not show significant streambed-elevation change (table 13), and the channel appeared to 

have changed little since it was altered. One possible 

explanation for this lack of incision is the topography 

of the subbasin. Unlike the rest of the Salt Creek 

Basin, which drains rolling hills of glacial till (Dugan, 

1984), the entire Clear Creek subbasin drains an abandoned flood plain of the Platte River (Soil Conservation Service, 1965). Less stream energy is associated 

with the gentle grade of the flood plain than that of 

rolling hills, which may be the reason that incision has 

not occurred.
45 Streambed Adjustment and Channel Widening in Eastern Nebraska

The Sand Creek stream channels appeared more 

incised than those of Cottonwood Creek and NorthFork Wahoo Creek. Streambed-elevation data further 

verified this difference (table 13). 

Urbanization may have caused the aggradation 

seen at all Beal Slough sites upstream from SC-E 

(table 13), where development in the upper parts of the 

subbasin is still occurring. Streambed degradation of 

Beal Slough downstream from SC-F may have been 

caused by both urbanization (which increased streamflow) as well as the migration of a response from the 

original channelization, which may have been stopped 

by the culvert at SC-F. Although Beal Slough is 

aggrading upstream from SC-F, severe head cutting 

between sites SC-B and SC-C was observed in 1997 

when a new culvert was installed at a lower elevation 

than the previous culvert (Olsson Associates and 

Wright Water Engineers, 2000).

Little Nemaha River Basin

Documented Disturbances, Knickpoints, and 

Grade-Control Structures

The Little Nemaha River was dredged and 

straightened in the early 1900s (fig. 28). These disturbances have been the primary cause of channel instabilities in the basin, although most streambed effects 

already have occurred. Straightening of the South Fork 

Little Nemaha River and Muddy Creek in the late 

1940s and early 1950s caused further instability in 

those subbasins. 

Original Straightening

In the late 1800s and early 1900s, flooding in 

the Little Nemaha River Basin was becoming increasingly frequent, even though weather records indicated 

no increase in precipitation in that time period (Mears, 

1912). The channel had lost as much as 30 percent of 

its capacity from the accumulation of cut timber and 

sediment in the channel (Mears, 1912) and was 

aggrading (Moore, 1915). To rectify this situation, 

drainage districts were formed (table 14), and the 

Little Nemaha River, along with some of its tributaries, was straightened and cleared of vegetation from 

its mouth upstream to Syracuse, Nebraska (fig. 28) 

(Moore, 1915). In Nemaha County, the Little Nemaha 

River was designed to a 4.27-m depth, and the tributary streams were to be 0.9- to 3.7-m deep (Mears, 

1912). 

Knickpoints created by this disturbance seemed 

to have migrated to the upstream sites in the 1960s and 

likely have progressed to the upper reaches of the 

tributaries in the basin. In 1998, a steepened reach with 

an incised channel was observed on Spring Creek 

approximately 3.5 RKM upstream from LNR-11 

(fig. 29), which may have been the result of this channelization. 

Culverts are common in the upper parts of the 

basin because the streams are smaller, and therefore, 

knickpoints may be prevented from migrating any 

farther upstream. At LNR-A, the bridge was replaced 

by a culvert, but not before 3.0 m of degradation had 

occurred. In addition to the culverts, a grade-control 

structure on the North Fork Little Nemaha River near 

Lorton, Nebraska, was installed in the late 1980s to 

protect the channel from a large overfall that was 

migrating upstream.

Channelization in the South Fork Little Nemaha River 

and Muddy Creek Subbasins

Channelization was extended on the South Fork 

Little Nemaha River and Muddy Creek between 1947 

and 1953. The modifications on the South Fork Little 

Nemaha River appear to have been extended from the 

Otoe-Johnson County line to a point about 10 RKM 

upstream in the late 1940s (fig. 28). Aerial photographs of the stream at site LNR-8 in the 1940s show 

an incised channel with numerous point bars, indicating that the South Fork Little Nemaha River already 

had degraded from the original modifications and 

probably was aggrading when the channelization was 

extended. 

The Muddy Creek modifications were extended 

from about 1 RKM upstream from the confluence with 

the Little Nemaha River to about 10 RKM upstream 

from the confluence, or just upstream from site LNR-6 

(fig. 28), in the late 1940s and early 1950s. Aerial 

photographs from 1949 of the channel upstream from 

where the modifications were completed show little or 

no incision, indicating that the disturbance caused by 

the original modifications had not yet migrated 

upstream through the subbasin before the channelization was extended. In response to the large amount of 

degradation at site LNR-B (6.6 m between 1946 and 

1978), a grade-control structure was installed at the 

site in 1979 that has stabilized the streambed. A steepened reach that was presumably a result of the original 

Muddy Creek disturbance was observed approxi-
STREAMBED ADJUSTMENT 46

 3 LNRLNR-12

 4 LNR-

 1 LNR-

 2 LNR- 13 LNR- A LNR-

 5 LNR-

 7 LNR- 15 LNR-

 6 LNR-

 B LNR-

 LNR-14

 11 LNR-

 8 LNR-

 16 LNR-

 9 LNR-

 17 LNR-

 10 LNR-

 

 

AUBURN

SYRACUSE

LORTON

Whiskey Run

Little Nemaha River

Rock Creek

N. Fork Little Nemaha River

Muddy

Creek

S. Fork Little Nemaha River

Spring Creek

Silver Creek

Little Nemaha Ri ver

Hooper Creek

Wolf Creek

41 ̊15'

96 ̊45'

96 ̊

96 ̊15'

40 ̊30'

40 ̊45'

96 ̊30'

0 5 0 5 1

Nebraska

Location map

Study area

Studybasin

Base from U.S. Geological Survey1:100,000 digital dataAlbers Equal-Area Conic projection Standard parallels 29 ̊30' and 45 ̊30'

central meridian -96 ̊00'

EXPLANATION

LNR-2

LNR-B

Channelization in the South Fork, Little Nemaha and Muddy Creek subbasins

Grade-control structures

Basin boundaryOriginal straighteningPrimary study site and identification Supplemental study sites and identification Town

KnickpointsStream

Figure 28. Location of the Little Nemaha River Basin and associated study sites in Nebraska.
47 Streambed Adjustment and Channel Widening in Eastern Nebraska

mately 8 RKM upstream from site LNR-6 in 1995, 

where the stream gradient was approximately

0.050 m/m.

Streambed Summaries

The amount of streambed gradation that 

followed the original channelization was estimated at 

six sites by determining the original constructed 

streambed elevations from the planned channel dimensions (Mears, 1912). For the purposes of this report, it 

was assumed that the design depth of the main ditch at 

LNR-5 and LNR-14 in Otoe County was similar to 

that in Nemaha County. Additionally, a 3.7-m 

constructed tributary depth (based on Mears, 1912) 

was assumed for site LNR-8. The results of this study 

indicate that the straightened reaches of the Little 

Nemaha River Basin have degraded substantiallysince 

the original channelization was completed (table 15). 

Table 14. Drainage districts associated with the Little Nemaha River Basin

Drainage district name1 Streams that may have been straightened

Date drainage 

plans were 

approved1

Nemaha County Drainage District No. 2 Little Nemaha River 21910

Nemaha County Drainage District No. 3 Little Nemaha River July 6, 1916

Otoe-Johnson County Drainage District No. 1 North Fork, South Fork, and main 4stem of 

Little Nemaha River, and Muddy Creek

October 31, 1914

Otoe-Johnson County Drainage District No. 1 

(Spring Creek cut-off)

Spring Creek September 15, 1932

1 From Nebraska Department of Roads and Irrigation, 1954.

2 From Mears, 1912.

Presumably, this response has migrated into the upper 

reaches of the basin and has caused channel incision.

Two of the three sites in the South Fork Little 

Nemaha River subbasin (LNR-8 and LNR-9) showed 

a response probably caused by the straightening in the 

subbasin between 1947 and 1953 (fig. 30; table 15). 

The third site, LNR-7, which is in the upper reaches 

of the subbasin, seems presently to be aggrading in 

response to the original channelization. This would 

indicate that a knickpoint created by the extension of 

the work may still be migrating upstream through the 

subbasin and is located between sites LNR-7 and 

LNR-8. Sites in the Muddy Creek subbasin had the 

most streambed degradation of any of the sites in the 

basin, with 6.0 m of change at LNR-B and 5.4 m of 

change at LNR-6 (table 15).

310

311

312

313

314

315

316

ELEVATION, IN METERS ABOVE 

NGVD OF 1929

1900 1920 1940 1960 1980 2000

Figure 29. Channel incision observed in 1998 on Spring 

Creek about 3.5 kilometers upstream from LNR-11.

Figure 30. Streambed-elevation changes at S Fk Little 

Nemaha River at N50 (LNR-8).
STREAMBED ADJUSTMENT 48

Table 15. Streambed summaries for sites in the Little Nemaha River Basin

[ID, identification; RKM, river distance (in kilometers from the mouth); n, number of streambed elevation points used; ∆E, difference in streambed elevation 

between first and last streambed-elevation points, in meters; d50, median streambed grain-size diameter, in millimeters; L, loam; SICL, silty clay loam; 

SIL, silt loam; S, sand; SL, sandy loam; GR, gravelly; LS, loamy sand; --, not available]

Site ID RKM n ∆E

(m)

First 

year

Last 

year

d50

(mm)

Textural 

class Comments

LNR-1 108.0 6 –0.8 1961 1999 0.039 L

LNR-2 92.3 5 –1.8 1951 1999 0.018 SICL

LNR-3 98.3 3 –0.3 1983 1997 0.019 SICL

LNR-4 83.7 58 –2.1 1951 1999 0.027 SIL

LNR-A 68.9 80 –3.0 1950 2000 -- --

LNR-5 61.5 24 –4.3 1914 1999 0.61 S Most of the degradation was based on the estimate 

of 1914 streambed elevation.

LNR-6 62.8 5 –5.4 1953 1999 0.31 SL Some of the degradation was based on the estimate 

of 1953 streambed elevation.

LNR-B 56.5 5 –6.0 1946 1997 -- --

LNR-7 95.1 6 –2.0 1965 1999 0.66 GR S

LNR-8 62.7 6 –5.4 1920 1999 0.71 S Most of the degradation was based on the estimate 

of 1920 streambed elevation.

LNR-9 73.4 5 –1.4 1948 1999 0.54 SL

LNR-10 80.0 4 –0.2 1964 1999 0.032 SIL

LNR-11 57.0 5 –1.6 1962 1999 0.69 LS

LNR-12 82.9 5 –1.6 1957 1999 0.050 SIL

LNR-13 63.1 4 0.3 1963 1999 0.031 SIL

LNR-14 41.7 7 –3.7 1912 1997 0.74 S Most of the degradation was based on the estimate 

of 1912 streambed elevation.

LNR-15 47.5 4 –0.4 1955 1999 0.044 SIL

LNR-16 32.3 5 –1.9 1960 1999 0.019 SICL

LNR-17 16.8 22 –1.7 1912 1997 0.82 GR S Some of the degradation was based on the estimate 

of 1912 streambed elevation.

LNR-18 2.5 4 1.3 1912 1998 0.017 SICL The 1912 streambed elevation was estimated.

LNR-19 2.0 7 1.4 1912 1998 0.026 SIL The 1912 streambed elevation was estimated.
49 Streambed Adjustment and Channel Widening in Eastern Nebraska

Big Nemaha River Basin

Documented Disturbances, Knickpoints, and 

Grade-Control Structures

Dredging and straightening of the main stems of 

streams in the Big Nemaha River Basin (fig. 31) in the 

early 1900s have been the primary cause of channel 

instabilities in the basin, although most of the effects 

to the streambed already have occurred. 

In response to flooding in the basin, most of 

Muddy Creek (a separate stream from that of the Little 

Nemaha River Basin), the Big Nemaha River, and 

parts of its North and South Forks were channelized in 

the early 1900s (fig. 31). In addition to the work done 

in Nebraska by several drainage districts (table 16), 

reaches of the South Fork Big Nemaha River in 

Kansas also were channelized, probably at about the 

same time as the work was completed in Nebraska. 

Constructed channel depths were not given for most 

drainage districts, but Moore (1915) reported that the 

Richardson County Drainage District No. 2 dug a 

channel 6 m deep and 9 m wide in the North Fork Big 

Nemaha River. In addition to the original work done 

on Muddy Creek around 1917, a short reach near site 

BNR-16 was rechannelized by Richardson County 

Drainage District No. 6 in 1936 (fig. 31). 

The channels in the basin began degrading and 

widening almost immediately after being channelized. 

Five years after it was channelized in 1909, the 

channel at BNR-9 had degraded considerably and had 

doubled in width (U.S. Army Corps of Engineers, 

1995) (fig. 32). Most of the knickpoints created by this 

disturbance have already migrated into the upper 

reaches of the basin. Two knickpoints were observed 

on small tributaries to Muddy Creek near BNR-17. 

Exposed bedrock serves as a grade-control structure in 

the streambeds of BNR-9, BNR-12, and BNR-14. 

Streambed Summaries

The results of this study agree with those of a 

study done by the USACE in 1995, which indicated 

that although they have degraded considerably (table 

17), the channelized streams in the Big Nemaha River 

system are no longer degrading in response to the 

straightening completed in the 1900s. For example, 

BNR-14 experienced 4.5 m of degradation between 

1905 and 1982 but only 0.1 m of aggradation since 

1982 (table 17). A degrading channel response to this 

disturbance is probably still occurring in the upper 

reaches of the basin. A knickpoint may have migrated 

through site BNR-11 on Turkey Creek sometime 

around 1968 but has yet to reach BNR-10 (Rus and 

Soenksen, 1998). The degradation occurring in the 

middle and upper reaches of Turkey Creek may be the 

cause of aggradation seen in the lower reaches 

(table 17) (Drees and others, 1996). The upper reaches 

of other tributaries were still undergoing incision as 

late as 1972 (Soil Conservation Service, 1972), and 

site BNR-1 at RKM 143.0 may have begun responding 

to this disturbance as late as 1980. 

Table 16. Drainage districts associated with the Big Nemaha River Basin

Drainage district name1 Streams that may have been straightened Date drainage plans 

were approved1

Richardson County Drainage District No. 1 Big Nemaha River, North Fork Big Nemaha River, and South 

Fork Big Nemaha River

19042

Richardson County Drainage District No. 2 North Fork Big Nemaha River 19092

Richardson County Drainage District No. 3 Big Nemaha River, North Fork Big Nemaha River, South Fork 

Big Nemaha River, and Muddy Creek

December 24, 1921

Richardson County Drainage District No. 4 Big Nemaha River, North Fork Big Nemaha River, South Fork 

Big Nemaha River, and Muddy Creek

April 13, 1916

Richardson County Drainage District No. 5 Big Nemaha River, North Fork Big Nemaha River, South Fork 

Big Nemaha River, and Muddy Creek

May 8, 1920

Richardson County Drainage District No. 6 Muddy Creek September 18, 1930

Nemaha County Drainage District No. 3 Muddy Creek July 6, 1916

Pawnee County Drainage District No. 12 North Fork Big Nemaha River Around 19122

Johnson County Drainage District No. 12 North Fork Big Nemaha River Around 19142

1 Unless otherwise noted, from Nebraska Department of Roads and Irrigation, 1954. 2 From Moore, 1915.
STREAMBED ADJUSTMENT 50

ek

 1 BNRBNR-2

BNR- 3

BNR-15

 6 BNRBNR- 5

 4 BNRBNR- 7

BNR-16

BNR-10

BNR-8

 9 BNRBNR-17

BNR-11

BNR-13

BNR-14

BNR-12

 A BNRTurkey Creek

Johnson Creek

S Fk Big Nemaha River

N Fk Big Nemaha River Big Nemaha Riv e r

Nebraska

Kansas

40 ̊

40 ̊30'

95 ̊30'

96 ̊

96 ̊30'

Base from U.S. Geological Survey

1:100,000 digital data

Albers Equal-Area Conic projection

Standard parallels 29 ̊30' and 45 ̊30'

central meridian -96 ̊00'

Location map

Study area

Study

basin 

0 5 10 MILES

0 5 10 KILOMETERS

EXPLANATION

Basin boundary

Original straightening, 1904–30

BNR-2

BNR-A

Primary study site and identification 

Supplemental study site and identification 

Town

Knickpoints

Stream

Rechannelized area, 1936

Falls City

Humbolt

Tecumseh

Rulo

Middle Br Big Tecumseh Riv er

Yankee Creek

Long Branch Creek

Kirkham Cr

Figure 31. Location of the Big Nemaha River Basin and associated study sites in Nebraska.
51 Streambed Adjustment and Channel Widening in Eastern Nebraska

Table 17. Streambed summaries for sites in the Big Nemaha River Basin

[ID, identification; RKM, river distance (in kilometers from the mouth); n, number of streambed-elevation points used; ∆E, difference in streambed 

elevation between first and last streambed-elevation points, in meters; d50, median streambed grain-size diameter, in millimeters; SL, sandy loam; S, sand; LS, 

loamy sand; SIL, silt loam; GRX, extremely gravelly; L, loam; --, not available]

Site ID RKM n ∆E

(m)

First 

year

Last 

year

d50

(mm)

Textural 

class Comments

BNR-1 143.0 4 –1.1 1980 1999 0.28 SL

BNR-2 152.6 7 –1.5 1962 1999 0.093 SL

BNR-3 137.6 5 –1.9 1954 1999 0.36 SL

BNR-4 131.3 4 –1.8 1979 1999 0.082 S

BNR-5 111.5 8 –3.7 1917 1999 0.65 LS Most of the degradation was based on the 

estimate of 1917 streambed elevation.

BNR-6 99.9 8 –3.9 1914 1999 0.029 SIL Most of the degradation was based on the 

estimate of 1914 streambed elevation.

BNR-7 82.6 5 –0.8 1957 1999 0.38 S

BNR-8 65.7 3 –0.1 1968 1999 0.18 SL

BNR-9 58.9 31 –7.9 1916 1999 0.61 S Most of the degradation was based on the 

estimate of 1916 streambed elevation.

BNR-10 180.2 4 –0.6 1968 1999 0.031 SIL

BNR-11 136.3 8 –3.0 1949 1999 0.44 LS

BNR-12 132.7 4 0.2 1964 1999 10 GRX S Cobble streambed.

BNR-A 100.5 32 0.2 1958 1994 -- --

BNR-13 64.3 3 –2.3 1959 1997 0.47 SL

BNR-14 22.2 34 –4.4 1905 1993 0.55 S Most of the degradation was based on the 

estimate of 1905 streambed elevation.

BNR-15 77.8 8 –2.9 1935 1999 0.074 L

BNR-16 53.0 8 –7.7 1927 1999 0.25 SL

BNR-17 35.2 17 –2.6 1921 1999 0.55 S Most of the degradation was based on the 

estimate of 1921 streambed elevation.
STREAMBED ADJUSTMENT 52

Big Blue River Basin

Because of a lack of channelization and the 

presence of grade-control structures, most sites in the 

Big Blue River Basin (fig. 33) did not show streambed-elevation changes similar to those observed in 

other basins. However, local straightening was 

completed on a few tributary subbasins and gradation 

responses were observed. 

Documented Disturbances, Knickpoints, and 

Grade-Control Structures

Local reaches of several tributaries to the Big 

Blue River were straightened over the years, which in 

some cases likely instigated responses within those 

tributary subbasins. The tributaries that show evidence 

of straightening in local reaches include the North 

Branch Big Blue River, Kezan Creek, Indian Creek, 

and Big Indian Creek (fig. 33). 

Aerial photographs show that the middle and 

upper reaches of Kezan Creek were straightened prior 

to 1938. A knickpoint with a 0.25-m water surface 

drop over a 2.3-m distance was observed 150 m 

upstream from the bridge at site BBR-3 in 1997. 

Photographs of the site from 1985 show what appears 

to be a knickpoint about 50 m upstream from the 

bridge. If the 1985 knickpoint is the same as that 

observed in 1997, the knickpoint is moving approximately 8 m/yr. 

Flooding problems in Beatrice, Nebraska, 

prompted channel modifications on Indian Creek 

between 1944 and 1946 (U.S. Army Corps of Engineers, 1970). These modifications extended from the 

confluence with the Big Blue River upstream approximately 1.8 km, and consisted of a channel with a 

15-m-bottom width and 1:1.5 bank slopes (U.S. Army 

Corps of Engineers, 1970). Additionally, rock riprap 

was added to the bed in the vicinity of this site to 

protect it from degradation. 

To reduce flooding in local areas, individual 

landowners straightened short reaches of Big Indian 

Creek, which resulted in bank erosion and channel 

degradation (Soil Conservation Service, 1962). A 

grade-control structure was in place since at least 1998 

on Big Indian Creek between sites BBR-11 and BBR12 (fig. 34). Much of the lower basin overlies Quaternary-age deposits of shale and sandstone (Swinehart 

and others, 1994), which provided an erosion-resistant 

surface once it was exposed. 

Although no large-scale straightening was 

performed on the Big Blue River, up to 20 overflow 

dams (dams just above the low-water level) provide 

grade control (Nebraska Soil and Water Conservation 

Commission, 1968). Originally built for power 

production, some of these dams have been in place 

since the 1860s. Although scour effects occurred 

downstream from these overflow dams, the scoured 

reaches were relatively short and did not lead to 

measured degradation except at site BBR-13, which 

was 1.1 km downstream from one of these structures. 

Streambed Summaries

Of the six sites on tributaries that have been 

straightened, only BBR-12 showed any streambed 

degradation greater than 1 meter (table 18). This may 

be a result of grade-control structures, but also might 

be the result of insufficient data at the other sites. 

Bedrock currently is exposed at site BBR-12, which 

has effectively halted any further degradation.

1900 286

287

288

289

290

291

292

293

294

295

296

ELEVATION, IN METERS ABOVE 

NGVD OF 1929

1920 1940 1960 1980 2000

Figure 32. Streambed-elevation changes at N Fk Big 

Nemaha R at N105 (BNR-9).
53 Streambed Adjustment and Channel Widening in Eastern Nebraska

BBR-3

BBR-2

BBR-1 BBR-4

BBR-5

BBR-6

BBR-8

BBR-7

BBR-9

BBR-10

BBR-12 BBR-11

BBR-13

BEATRICE

BARNESTON

Kezan Cree k

Big Blue River Big Blue Rive r

Big Blue River N Br Big B ul e R vi e r

Big Indian Cree k

I n ndia Cre e k

Turkey Creek

41 ̊

40 ̊30'

40 ̊

39 ̊30'

97 ̊

97 ̊30'

98 ̊30'

98 ̊

96 ̊30

Base from U.S. Geological Survey

1:100,000 digital data

Albers Equal-Area Conic projection

Standard parallels 29 ̊30' and 45 ̊30'

central meridian -96 ̊00'

0 5 10 MILES

0 5 10 KILOMETERS

EXPLANATION

Channelized stream reach

BBR-2

Grade-control structures

Basin boundary

Primary study site and identification 

Town

Knickpoints

Stream

Nebraska

Location map

Study area

Study

basin 

Kansas

Figure 33. Location of the Big Blue River Basin and associated study sites in Nebraska.
STREAMBED ADJUSTMENT 54

Table 18. Streambed summaries for sites in the Big Blue River Basin

[ID, identification; RKM, river distance (in kilometers from the mouth); n, number of streambed elevation points used; ∆E, difference in streambed elevation 

between first and last streambed-elevation points, in meters; d50, median streambed grain-size diameter, in millimeters; SIL, silt loam; L, loam; S, sand; GR, 

gravelly; SL, sandy loam; --, not available]

Site ID RKM n ∆E

(m)

First 

year

Last 

year

d50

(mm)

Textural 

class Comments

BBR-1 265.3 9 0.0 1964 1999 0.026 SIL The site is in backwater conditions created by 

low-head dam downstream.

BBR-2 293.7 3 0.1 1971 1999 0.027 SIL

BBR-3 273.1 4 –0.3 1970 1999 -- --

BBR-4 249.6 6 –0.9 1969 1999 0.029 SIL

BBR-5 120.6 18 0.4 1952 1996 0.056 L

BBR-6 96.3 19 –0.1 1959 1999 0.61 S

BBR-7 77.0 4 0.5 1956 1998 0.42 S

BBR-8 69.9 5 –0.3 1932 1999 0.050 L

BBR-9 44.2 18 –0.9 1968 1999 0.48 S

BBR-10 39.8 23 0.2 1913 1996 0.90 GR S

BBR-11 55.2 4 0.1 1994 1999 0.55 SL

BBR-12 15.3 10 –1.1 1939 1997 -- -- Cobble streambed.

BBR-13 0 37 0.0 1941 1992 0.085 GR L

Figure 34. Grade-control structure on Big Indian Creek 

between Gage County Road (BBR-11) and US77 

(BBR-12).
CHANNEL WIDENING 55

CHANNEL WIDENING

Top-of-bank widening was evaluated at 73 of 

the primary sites, where extensive first-round 

surveying was done. A comparison of first- and 

second-round surveys showed TOB widening at 64 of 

those sites. Individual failures were characterized for 

each of these sites, and the length and width of each 

failure were tabulated (table 19).

The widening rates (table 20) were calculated as 

comparative measures rather than predictive relations, 

and the rates should be used for that limited purpose. 

Because widening at meandering reaches could be a 

function of lateral channel migration as well as bank 

failure related to oversteepened banks, the planform 

characteristics of the surveyed reach are provided 

(table 20). The greatest amount of widening observed 

in meandering reaches was at site BNR-16, which had 

widened 6.9 m at one survey point in 25 months. At 

the sites with straight reaches, the most widening was 

Table 19. Individual top-of-bank failure dimensions

[ID, identification; all measurements are in meters; --, not applicable]

Site ID

Individual failure Individual failure Individual failure Individual failure

Length, lf Width, wf Length, lf Width, wf Length, lf Width, wf Length, lf Width, wf

Missouri River Tributary Basins

MRT-2 16.8 0.6 -- -- -- -- -- --

MRT-3 10.0 0.7 -- -- -- -- -- --

MRT-4 9.0 1.3 6.7 1.0 9.9 0.9 8.7 0.4

9.9 0.6 17.3 0.2 8.3 0.6 -- --

MRT-9 10.3 0.4 7.7 0.7 22.7 1.3 -- --

MRT-10 22.4 1.2 11.7 2.1 17.2 1.5 6.0 1.5

14.2 1.4 17.3 1.5 -- -- -- --

MRT-15 4.4 2.5 6.9 0.9 6.6 0.3 10.3 0.4

MRT-16 8.8 1.4 10.7 1.1 -- -- -- --

MRT-17 22.1 0.3 9.8 0.4 5.3 0.4 16.5 0.5

Papillion Creek Basin

PC-8 2.8 2.9 -- -- -- -- -- --

Platte River Tributary Basins

PRT-1 12.3 0.3 14.6 0.2 -- -- -- --

PRT-2 18.1 0.3 14.8 0.4 8.3 0.1 -- --

PRT-5 39.7 2.7 9.5 1.0 -- -- -- --

PRT-6 14.3 1.7 -- -- -- -- -- --

PRT-7 13.0 0.5 26.5 2.1 17.6 2.4 36.2 0.7

17.2 1.7 -- -- -- -- -- --

Elkhorn River Basin

ER-5 18.9 0.4 10.0 0.3 17.8 0.4 -- --

ER-6 67.6 1.1 -- -- -- -- -- --

ER-7 19.9 0.3 19.0 1.0 -- -- -- --

ER-8 8.2 0.7 9.1 0.8 5.8 0.9 18.6 0.5

32.1 0.4 11.0 0.6 -- -- -- --

ER-9 14.7 0.8 16.7 1.3 71.4 1.3 -- --

ER-15 8.9 0.7 4.2 0.7 -- -- -- --

ER-16 6.1 0.3 14.7 0.3 8.0 1.0 3.3 0.3

7.0 1.0 5.3 0.6 8.9 1.2 20.8 0.5

ER-18 9.9 0.7 4.6 0.4 9.1 0.5 -- --

ER-20 6.2 0.2 5.6 0.5 17.7 0.4 13.5 0.3

12.3 0.6 9.4 0.7 16.8 0.4 -- --

ER-21 9.0 0.6 -- -- -- -- -- --
CHANNEL WIDENING 56

Salt Creek Basin

SC-10 41.4 3.1 9.9 0.4 -- -- -- --

SC-11 7.1 0.8 -- -- -- -- -- --

SC-12 7.4 0.3 -- -- -- -- -- --

SC-14 29.3 1.9 20.1 1.0 -- -- -- --

SC-15 6.5 0.7 -- -- -- -- -- --

SC-16 3.8 3.7 11.7 0.4 -- -- -- --

SC-18 5.9 0.6 -- -- -- -- -- --

SC-20 5.9 0.4 7.8 1.1 9.3 0.5 6.8 0.5

4.0 0.8 15.1 0.7 11.7 0.8 26.7 0.8

17.4 1.0 2.7 0.4 8.0 0.6 17.9 0.7

SC-25 16.2 1.5 -- -- -- -- -- --

SC-28 9.7 0.4 8.7 0.7 -- -- -- --

SC-32 7.4 0.7 16.8 0.7 4.4 0.6 16.7 0.6

SC-33 26.0 2.4 -- -- -- -- -- --

Little Nemaha River Basin

LNR-3 7.2 1.5 7.8 0.4 10.9 1.0 2.7 0.5

5.6 1.3 3.2 0.6 2.0 0.6 6.3 2.1

25.9 1.2 -- -- -- -- -- --

LNR-4 22.7 0.7 -- -- -- -- -- --

LNR-5 59.2 0.8 11.9 0.7 -- -- -- --

LNR-6 13.5 0.7 12.6 0.5 7.6 0.3 9.9 0.2

33.7 0.3 -- -- -- -- -- --

LNR-12 18.3 0.5 5.7 0.2 5.8 0.5 11.4 0.2

LNR-16 8.0 0.4 10.3 0.5 7.5 0.5 13.0 0.3

6.3 0.3 11.4 0.3 11.1 2.8 -- --

Big Nemaha River Basin

BNR-1 9.7 0.2 5.1 0.4 5.4 0.1 -- --

BNR-2 8.6 0.1 4.8 0.3 7.5 0.1 9.8 0.2

BNR-3 12.3 0.9 -- -- -- -- -- --

BNR-4 13.4 0.2 -- -- -- -- -- --

BNR-5 8.6 0.8 9.6 0.4 45.1 1.9 -- --

BNR-7 4.4 0.3 -- -- -- -- -- --

BNR-8 5.5 0.2 8.6 0.3 -- -- -- --

BNR-9 50.9 2.7 11.6 0.3 17.6 0.3 37.9 1.9

7.5 0.5 -- -- -- -- -- --

BNR-10 12.5 0.5 16.8 0.4 10.8 0.4 15.0 0.3

BNR-13 36.7 1.4 51.9 0.6 47.5 0.5 28.8 0.4

BNR-14 21.5 2.5 17.4 0.3 3.1 0.6 83.8 0.5

BNR-15 8.0 0.5 10.5 0.5 25.4 0.8 -- --

BNR-16 52.3 3.7 -- -- -- -- -- --

BNR-17 4.2 0.7 32.5 0.8 46.7 1.5 -- --

Table 19. Individual top-of-bank failure dimensions—Continued

[ID, identification; all measurements are in meters; --, not applicable]

Site ID

Individual failure Individual failure Individual failure Individual failure

Length, lf Width, wf Length, lf Width, wf Length, lf Width, wf Length, lf Width, wf
CHANNEL WIDENING 57

observed at site BBR-5, which at one location had 

widened by 6.4 m in 26 months. 

All eight sites in the Big Blue River Basin 

showed widening, including the site with the most 

widening in a straight reach. Only a small number of 

tributaries in the basin were disturbed through channelization. Streambed-elevation data sets for Big Blue 

River Basin sites generally show little change. 

Because failures were observed at the sites, it was 

assumed that the measured widening was accurate. 

Considering the lack of major straightening in the Big 

Blue River Basin, the widening observed may indicate 

that other disturbances are occurring in the basin that 

are not caused by streambed degradation, which could 

include changes in land use as the basin has been 

converted to a primarily agricultural watershed. 

However, it may also indicate that the variability in the 

streambed-elevation data sets may have been too large 

to accurately identify streambed responses.

Big Blue River

BBR-1 10.0 0.8 -- -- -- -- -- --

BBR-2 3.1 0.3 5.2 0.8 4.6 0.5 5.4 0.5

5.1 0.2 4.8 0.3 1.0 0.4 2.6 1.1

1.4 0.5 1.6 0.4 1.8 1.4 1.3 0.3

4.2 0.4 2.5 0.6 6.6 0.5 5.6 0.2

1.9 1.6 2.1 0.4 -- -- -- --

BBR-3 6.5 0.5 12.6 0.5 3.7 0.4 6.6 0.3

14.9 0.3 21.0 1.5 -- -- -- --

BBR-5 4.4 1.9 33 0.9 20.0 1.3 51.5 3.1

25.6 1.2 -- -- -- -- -- --

BBR-10 16.4 1.1 10.2 0.7 -- -- -- --

BBR-11 16.7 0.3 10.9 0.4 10.9 2.5 10.0 0.2

5.4 3.2 -- -- -- -- -- --

BBR-12 4.0 0.3 7.5 0.4 17.2 1.1 16.6 0.5

12.4 1.4 20.8 0.2 -- -- -- --

BBR-13 7.9 0.9 23.1 2.4 6.2 0.7 23.3 1.0

48.0 1.0 8.3 1.5 5.3 2.2 27.2 0.8

21.7 0.9 7.2 0.6 -- -- -- --

Table 19. Individual top-of-bank failure dimensions—Continued

[ID, identification; all measurements are in meters; --, not applicable]

Site ID

Individual failure Individual failure Individual failure Individual failure

Length, lf Width, wf Length, lf Width, wf Length, lf Width, wf Length, lf Width, wf
CHANNEL WIDENING 58

Table 20. Summary of observed channel widening[ID, identification; m, meter; m2, square meter; m/yr, meters per year; --, no widening was observed at the site between first- and second-round surveys]

Site ID Physical characteristic

Firstround 

survey 

date

Secondround 

survey 

date

Length 

of 

survey 

reach 

(m)

Number 

of individual 

failures

Mean Maximum

Failure 

length, lf

(m)

Weighted 

failure 

width, wf

(m)

Failure 

area, Af 

(m2)

Failure 

area, Af 

(m2)

Wide

poin

(m

Missouri River Tributary Basins

MRT-2 straight 6/24/97 10/3/98 175 1 16.8 0.6 10.3 10.3 0MRT-3 straight 6/24/97 7/15/99 191 1 10.0 0.7 6.9 6.9 1MRT-4 straight 6/25/97 10/2/98 77 7 10.0 0.7 6.6 12.0 1MRT-9 straight 12/10/96 10/23/98 210 3 13.5 0.8 12.7 28.6 2MRT-15 straight 7/15/97 5/4/99 81 4 7.0 1.0 5.8 10.8 4MRT-17 straight 7/24/97 11/30/98 145 4 13.4 0.4 5.7 8.9 4MRT-10 meander 12/9/96 10/23/98 250 6 14.8 1.6 22.2 27.3 1MRT-16 meander 12/4/96 2/26/99 364 2 9.8 1.3 12.2 12.3 2

Papillion Creek Basin

PC-8 straight 8/18/97 4/15/99 156 1 2.8 2.9 8.0 8.0 3

Platte River Tributary Basins

PRT-1 meander 6/2/97 3/31/99 137 2 13.5 0.3 3.3 3.4 0PRT-2 meander 8/21/97 12/3/98 114 3 13.7 0.3 4.2 6.1 1PRT-5 meander 7/30/97 7/1/99 128 2 24.6 1.9 59.2 109.0 5PRT-6 meander 7/21/97 4/20/99 115 1 14.3 1.7 24.1 24.1 2PRT-7 meander 6/17/97 7/9/99 164 5 22.1 1.5 31.6 55.4 3

Elkhorn River Basin

ER-18 straight 6/26/97 7/15/99 177 3 7.8 0.5 4.3 6.6 1ER-20 straight 4/24/97 4/2/99 92 7 11.6 0.5 5.3 7.6 1ER-21 straight 12/12/96 11/24/98 153 1 9.0 0.6 5.3 5.3 0ER-5 meander 8/20/97 4/20/99 125 3 15.5 0.4 5.7 8.0 1ER-6 meander 2/12/98 6/30/99 367 1 67.6 1.1 75.4 75.4 1ER-7 meander 7/29/97 4/13/99 73 2 19.5 0.7 12.7 18.8 1ER-8 meander 8/5/97 4/13/99 129 6 14.1 0.7 7.8 12.9 2ER-9 meander 6/5/97 4/2/99 114 3 34.3 1.2 42.2 92.0 2ER-15 meander 6/18/97 7/14/99 130 2 6.5 0.7 4.7 6.4 1ER-16 meander 8/20/97 4/13/99 104 8 9.3 0.7 5.9 10.7 1ER-25 meander 2/13/98 6/25/99 522 0 -- -- -- -- -
59 Streambed Adjustment and Channel Widening in Eastern Nebraska Salt Creek Basin SC-11 straight 8/15/97 4/7/99 127 1 7.1 0.8 5.6 5.6 1

SC-13 straight 10/21/96 5/18/99 639 0 -- -- -- -- -SC-16 straight 5/6/97 11/19/98 69 2 7.7 2.0 9.2 14.1 4SC-32 straight 6/17/97 6/30/99 167 4 11.3 0.7 7.5 11.2 1SC-34 straight 5/9/97 3/29/99 33 0 -- -- -- -- -SC-10 meander 8/27/97 4/6/99 113 2 25.6 1.7 65.4 126.7 4SC-12 meander 8/14/97 4/7/99 77 1 7.4 0.3 2.2 2.2 0SC-14 meander 3/12/96 11/1/98 65 2 24.7 1.4 37.6 55.2 3SC-15 meander 5/1/97 11/16/98 106 1 6.5 0.7 4.5 4.5 0SC-17 meander 3/19/97 1/29/99 33 0 -- -- -- -- -SC-18 meander 4/26/96 3/5/99 97 1 5.9 0.6 3.4 3.4 0SC-20 meander 5/14/96 3/5/99 438 12 11.1 0.7 8.3 22.6 2SC-22 meander 10/25/96 2/17/99 235 0 -- -- -- -- -SC-23 meander 10/30/96 2/10/99 167 0 -- -- -- -- -SC-25 meander 11/18/96 11/9/98 495 1 16.2 1.5 24.9 24.9 3SC-28 meander 5/8/97 12/16/98 127 2 9.2 0.6 5.1 6.1 1SC-33 meander 11/21/96 6/2/99 384 1 26.0 2.4 61.1 61.1 4

Little Nemaha River Basin

LNR-3 straight 3/6/97 2/3/99 121 9 7.9 1.0 9.0 31.5 4LNR-4 straight 6/5/97 3/30/99 171 1 22.7 0.7 15.9 15.9 1LNR-5 straight 7/14/97 6/17/99 124 2 35.5 0.8 27.8 47.4 2LNR-6 straight 5/29/97 3/3/99 90 5 15.5 0.4 6.3 11.6 1LNR-13 straight 5/1/97 3/30/99 120 0 -- -- -- -- -LNR-16 straight 3/21/97 2/8/99 126 7 9.6 0.7 7.3 31.3 5LNR-2 meander 3/7/97 2/5/99 109 0 -- -- -- -- -LNR-7 meander 5/16/97 3/1/99 104 0 -- -- -- -- -LNR-12 meander 3/11/97 2/8/99 130 4 10.3 0.4 3.8 8.6 0

Table 20. Summary of observed channel widening—Continued[ID, identification; m, meter; m2, square meter; m/yr, meters per year; --, no widening was observed at the site between first- and second-round surveys]

Site ID Physical characteristic

Firstround 

survey 

date

Secondround 

survey 

date

Length 

of 

survey 

reach 

(m)

Number 

of individual 

failures

Mean Maximum

Failure 

length, lf

(m)

Weighted 

failure 

width, wf

(m)

Failure 

area, Af 

(m2)

Failure 

area, Af 

(m2)

Wide

poin

(m
CHANNEL WIDENING 60

Big Nemaha River Basin

BNR-3 straight 5/20/97 3/3/99 94 1 12.3 1.0 11.7 11.7 1BNR-4 straight 5/30/97 3/26/99 43 1 13.4 0.2 2.7 2.7 0BNR-7 straight 6/20/97 6/13/99 58 1 4.4 0.3 1.4 1.4 0BNR-9 straight 11/26/96 7/13/99 432 5 25.1 1.2 45.0 138.9 5BNR-10 straight 7/23/97 1/28/99 174 4 13.8 0.4 5.3 6.0 1BNR-13 straight 7/23/97 1/28/99 227 4 41.3 0.7 29.6 52.5 3BNR-14 straight 11/27/96 1/21/99 318 4 31.5 1.0 25.5 53.0 5BNR-17 straight 12/5/96 1/19/99 213 3 27.8 1.0 32.1 68.9 5BNR-1 meander 5/22/97 3/1/99 43 3 6.7 0.2 1.5 2.2 0BNR-2 meander 5/14/97 3/3/99 57 4 7.7 0.2 1.3 2.4 0BNR-5 meander 7/22/97 4/12/99 112 3 21.1 1.0 31.4 83.5 4BNR-8 meander 6/20/97 7/13/99 104 2 7.0 0.3 2.1 3.0 0BNR-15 meander 5/28/97 2/3/99 78 3 14.6 0.6 9.8 20.3 1BNR-16 meander 6/19/97 7/20/99 117 1 52.3 3.7 194.6 194.6 6

Big Blue River Basin

BBR-3 straight 7/31/97 4/9/99 171 6 10.9 0.6 8.1 31.4 3BBR-5 straight 12/3/96 2/19/99 342 5 26.9 1.7 51.1 161.3 6BBR-13 straight 11/27/96 1/26/99 282 10 17.8 1.2 20.8 55.2 3BBR-1 meander 12/11/96 3/31/99 171 1 10.0 0.8 8.3 8.3 1BBR-2 meander 8/7/97 4/9/99 104 18 3.4 0.6 1.7 4.1 2BBR-10 meander 11/7/96 2/2/99 245 2 13.3 0.9 12.2 17.2 1BBR-11 meander 8/6/97 1/26/99 73 5 10.8 1.3 10.9 26.7 3BBR-12 meander 8/4/97 1/26/99 104 6 13.1 0.6 8.6 18.8 2

Table 20. Summary of observed channel widening—Continued[ID, identification; m, meter; m2, square meter; m/yr, meters per year; --, no widening was observed at the site between first- and second-round surveys]

Site ID Physical characteristic

Firstround 

survey 

date

Secondround 

survey 

date

Length 

of 

survey 

reach 

(m)

Number 

of individual 

failures

Mean Maximum

Failure 

length, lf

(m)

Weighted 

failure 

width, wf

(m)

Failure 

area, Af 

(m2)

Failure 

area, Af 

(m2)

Wide

poin

(m
SUMMARY AND CONCLUSIONS 61

SUMMARY AND CONCLUSIONS

In eastern Nebraska, stream straightening and 

dredging efforts since the 1890s have been the primary 

disturbances to the natural equilibrium of stream channels in the area. The resulting streambed degradation 

and subsequent channel widening from bank failures 

have damaged road structures, pipelines, fiber-optic 

lines, and land adjacent to the stream channels. This 

report describes a study by the U.S. Geological Survey 

(USGS), in cooperation with the Nebraska Department 

of Roads, Nebraska Natural Resources Commission 

(now part of the Nebraska Department of Natural 

Resources), Lower Platte South Natural Resources 

District, (NRD), Papio-Missouri River NRD, 

U.S. Army Corps of Engineers (USACE), and the U.S. 

Department of Agriculture, Agricultural Research 

Service (ARS), National Sedimentation Laboratory 

(NSL), of the effect these disturbances have had on 

streambed adjustment and channel widening in eastern 

Nebraska. Channel responses were characterized by 

estimating the amount of streambed-elevation change 

and documenting recent widening at several sites in 

eastern Nebraska.

Topographic and streambed grain-size data were 

collected at 151 primary sites in the study area. Two 

sets of survey data were collected approximately 

2 years apart. Generally, the first set of survey data 

was used to define the channel geometry, including the 

streambed elevation. The second set of survey data 

was used to document bank-widening and streambed 

gradation. Additionally, historical streambed-elevation 

data (dating back to the 1890s) were compiled from 

several sources for the 151 primary sites and 

45 supplemental sites, and relevant disturbances were 

identified for each basin. Streambed-elevation data 

sets were used to estimate the amount of change to the 

streambed at the sites over the time period of the data. 

Streambed degradation caused channel banks to 

become oversteepened, leading to channel widening. 

This widening was assessed by comparing first- and 

second-round survey data to document top-of-bank 

failures between the two surveys.

The majority of observed streambed-gradation 

responses appear to be related to the various straightening efforts that have taken place in the study area. 

The effects of grade-control structures have complicated responses at many of the sites studied. Because 

there were so many potential disturbances affecting 

the basins, the responses were complex and beyond 

the application of a streambed-elevation adjustment 

model. In many cases, the streambed-elevation data 

sets provide a reliable representation of past streambed 

gradation, with some sites showing 6 to 7 meters of 

degradation since they were straightened.

Because straightening plans or historical 

accounts that provided estimates of the original 

streambed elevation were only available in the 

Papillion Creek, Elkhorn River, Salt Creek, Little 

Nemaha River, and Big Nemaha River Basins, the full 

magnitude of gradation response following straightening could only be characterized at select sites in 

those basins. As a result, an unbiased comparison of 

gradation differences between basins was not possible.

Many sites where the original constructed 

streambed elevation could be estimated from straightening plans showed considerable degradation 

following the disturbance. This indicates that in 

eastern Nebraska, the coarse sediment supply is not 

sufficient to offset the effects of steepened stream 

slopes created by channelization. Instead, eastern 

Nebraska stream channels can regain equilibrium 

mainly through the slope adjustment process of headward-progressing degradation. 

Failures were documented at sites in all eight of 

the basin groupings analyzed, widening rates were 

computed at 64 of 73 sites. The documented channel 

widening indicates that other disturbances besides 

stream-channel straightening have probably caused 

channel responses in the Big Blue River Basin. Similar 

responses may be occurring in the other basins of the 

study area, although widening caused by straightening-induced streambed degradation cannot be 

isolated from that caused by other disturbances.

The data sets and results compiled in this report 

provide measures of past change to stream channels in 

eastern Nebraska. Channel responses have been 

complicated by the multiple disturbances that have 

occurred in the study area. Sites that may be showing 

little response now may still respond in the future, 

whether from the headward progression of existing 

knickpoints or through new disturbances. 

REFERENCES

Bentall, Ray, 1971, Water supplies and the land—The 

Elkhorn River Basin of Nebraska: University of 

Nebraska–Lincoln, Institute of Agriculture and Natural 

Resources, Conservation and Survey Division, 51 p.
62 Streambed Adjustment and Channel Widening in Eastern Nebraska

Bleed, Ann, and Flowerday, Charles, 1990, An atlas of the 

Sand Hills: University of Nebraska–Lincoln, Institute 

of Agriculture and Natural Resources, Conservation 

and Survey Division, 265 p.

Brook, W.E., Porterfield, J.C., and Yates, B.C., 1892, The 

Salt Creek rectification scheme: University of 

Nebraska-Lincoln, thesis, 32 p.

Chen, A.H., Rus, D.L., and Stanton, C.P., 1999, Trends in 

channel gradation in Nebraska streams: U.S. Geological Survey Water-Resources Investigations Report 

99–4103, 29 p., 15 apps., 1 pl.

Drees, R.H., Engelhard, Craig, and Kichler, Larry, 1996, 

Turkey Creek Watershed—Nebraska and Kansas 

riparian corridor report: Natural Resources Conservation Service, U.S. Department of Agriculture, 25 p.

Dugan, J.T., 1984, Hydrologic characteristics of Nebraska 

soils: U.S. Geological Survey Water-Supply Paper 

2222, 19 p., 12 pls.

Edwards, T.K., and Glysson, G.D., 1999, Field methods for 

measurement of fluvial sediment: U.S. Geological 

Survey Techniques of Water-Resources Investigations 

book 3, chap. C2, 89 p.

Elder, J.A., 1969, Soils of Nebraska: University of 

Nebraska-Lincoln, Institute of Agriculture and Natural 

Resources, Conservation and Survey Division, 

Resource Report No. 2, 60 p.

Farrar, Jon, and Gersib, Richard, 1991, Salt marshes—Last 

of the least: Lincoln, Nebr., Nebraska Game and Parks 

Commission, 23 p.

Federal Emergency Management Agency, 1997, Flood 

insurance study, City of Omaha, Douglas County: 

Washington D.C., Federal Emergency Management 

Agency, 48 p., 36 pls.

Fenneman, N.M., 1946, Physical divisions of the United 

States: Washington, D.C., U.S. Geological Survey, 

1 sheet.

Ferrell, John, 1996, Soundings—100 Years of the Missouri 

River navigation project: Kansas City, Mo., U.S. Army 

Corps of Engineers, 171 p.

Forstall, R.L., 1995, Population of counties by decennial 

census—1900 to 1990: Washington D.C., U.S. Bureau 

of the Census, accessed October 31, 2000 at URL 

http://www.census.gov/population/cencounts/

ne190090.txt 

Golden Software, Inc., 1995, Surfer® for windows—

Version 6, user’s guide: Golden, Colo., Golden Software, Inc., 480 p.

Kennedy, E.J., 1990, Levels at streamflow gaging stations: 

U.S. Geological Survey Techniques of WaterResources Investigations book 3, chap. A19, 27 p.

Kerstetter, T.M., 1992, Up the river—Flooding and the 

human response in Nebraska’s Elkhorn River Basin, 

through the floods of 1944: Lincoln, University of 

Nebraska, Master’s thesis, 139 p.

Langendoen, E.J., and Simon, Andrew, 2000, Stream 

channel evolution of Little Salt Creek and North 

Branch West Papillion Creek, eastern Nebraska: 

Oxford, Miss., National Sedimentation Laboratory, 

prepared for Lower Platte South and Papio-Missouri 

River Natural Resources Districts, 55 p., 2 apps.

Lower Platte South Natural Resources District, 1999, Beal 

Slough Basin model and plan: Lower Platte South 

Natural Resources District, accessed October 31, 2000, 

at URL http://www.lpsnrd.org/docs/beal.pdf

Lutenegger, A.J., 1987, In situ shear strength of friable 

loess, in Pécsi, Marton, ed., Loess and environment: 

Catena Supplement No. 9, p. 27–34.

Mackin, J.H., 1948, Concept of a graded river: Geological 

Society of America Bulletin, v. 59, p. 463–511.

Mandel, R.D., Bettis III, E.A., 1995, Late Quaternary landscape evolution and stratigraphy in eastern Nebraska, 

in Flowerday, C.A. (ed.), Geological field trips in 

Nebraska and adjacent parts of Kansas and South 

Dakota: 29th Annual Meeting of North-Central and 

South-Central Sections, Geological Society of 

America, Guidebook No. 10, University of Nebraska–

Lincoln, Institute of Agriculture and Natural 

Resources, Conservation and Survey Division, 

p. 77–99. 

Mears, L.W., 1912, Some geographical influences in the 

development of southeastern Nebraska, Nemaha 

County in particular: Lincoln, University of Nebraska, 

Master’s thesis, 49 p.

Moore, C.T., 1915, Drainage districts of southeastern 

Nebraska, in Barbour, E.H., An account of the 

Nebraska Geological Survey to 1912: Nebraska 

Geological Survey Miscellaneous Papers, v. 7, 

p. 125–164.

Natural Resources Conservation Service, 1996a, Rock 

Creek saline wetland cooperative river basin study: 

Lincoln, Nebr., U.S. Department of Agriculture, 

Natural Resources Conservation Service, 85 p.

———May 1996b, Map of the status of resource projects 

and river basins, Nebraska (revised May 1996): 

Lincoln, Nebr., U.S. Department of Agriculture, 

Natural Resources Conservation Service.

Nebraska Department of Agriculture and Inspection, 1957, 

Nebraska agricultural statistics, historical record 

1866–1954: Lincoln, Nebr., State-Federal Division of 

Agricultural Statistics, 176 p.

———1962, Nebraska agricultural statistics, Annual report 

1960, Preliminary report 1961: Lincoln, Nebr., StateFederal Division of Agricultural Statistics, 136 p.
REFERENCES 63

Nebraska Department of Agriculture, 1972, Nebraska agricultural statistics, Annual report 1970, Preliminary 

report 1971: Lincoln, Nebr., State-Federal Division of 

Agricultural Statistics, 160 p.

Nebraska Department of Agriculture, 1982, Nebraska agricultural statistics, Annual report 1980, Preliminary 

report 1981: Lincoln, Nebr., Nebraska Crop and Livestock Reporting Service, 164 p.

———1991, 1990–1991 Nebraska agricultural statistics: 

Lincoln, Nebr., Nebraska Agricultural Statistics 

Service, 148 p.

Nebraska Department of Natural Resources, 2003, Chapter 

6, Geodetic reference standards, accessed February 21, 

2003 at URL http://www.dnr.state.ne.us/databank/

metadata/geod_doc.txt

Nebraska Department of Roads and Irrigation, 1954, Thirtieth biennial report of the Department of Roads and 

Irrigation, 1953–1954, volume II: Lincoln, Nebr., 

Department of Roads and Irrigation, v. 2, 801 p.

Nebraska Natural Resources Commission, 1998, Biennial 

report on the Nebraska resources development fund: 

Lincoln, Nebr., Nebraska Natural Resources Commission, 22 p.

Nebraska Soil and Water Conservation Commission, 1968, 

Big Blue River Basin: Lincoln, Nebr., State Water Plan 

Publication Number 201, 103 p.

Olsson Associates and Wright Water Engineers, 2000, Beal 

Slough Basin stormwater master plan: Lincoln, Nebr., 

Olsson Associates, 74 p.

Papio-Missouri River Natural Resources District, 2000, 

Other flood-control measures: Papio-Missouri River 

Natural Resources District, accessed November 8, 

2000 at URL 

http://www.papionrd.org/programs/flodctrl.htm

Phipps, R.L., 1985, Collecting, preparing, cross-dating, and 

measuring tree increment cores: U.S. Geological 

Survey Water-Resources Investigations Report 

85–4148, 48 p.

Richardson, E.V., Harrison, L.J., Richardson, J.R., and 

Davis, S.R., 1993, Evaluating scour at bridges: U.S. 

Federal Highway Administration, FHWA–IP–90–017 

HEC–18.

Rus, D.L., and Soenksen, P.J., 1998, Channel stability of 

Turkey Creek, Nebraska, in Abt, S.R., Young-Pezeshk, 

Jayne, and Watson, C.C., eds., Water Resources Engineering 98—International Water Resources Engineering Conference, August 3–7, 1998, Memphis, 

Tennessee, Proceedings: Reston, Va., American 

Society of Civil Engineers, v. 1, p. 423–428.

Schoeneberger, P.J., Wysocki, D.A., Benham, E.C., and 

Broderson, W.D., 1998, Field book for describing and 

sampling soils: U.S. Department of Agriculture, 

version 1.1.

Schumm, S.A., Harvey, M.D., and Watson, C.C., 1984, 

Incised channels—Morphology, dynamics, and 

control: Littleton, Colo., Water Resources Publications, 200 p.

Simon, Andrew, 1989, A model of channel response in 

disturbed alluvial channels: Earth Surface Processes 

and Landforms, v. 14, p. 11–26.

———1994, Gradation processes and channel evolution in 

modified west Tennessee streams—Process, response, 

and form: U.S. Geological Survey Professional 

Paper 1470, 84 p.

Simon, Andrew, and Hupp, C.R., 1992, Geomorphic and 

vegetative recovery processes along modified stream 

channels of West Tennessee: U.S. Geological Survey 

Open-File Report 91–502, 142 p. 

Soenksen, P.J., Miller, L.D., Sharpe, J.B., and Watton, J.R., 

1999, Peak-flow frequency relations and evaluation of 

the peak-flow gaging network in Nebraska: U.S. 

Geological Survey Water-Resources Investigations 

Report 99–4032, 47 p., 3 apps.

Soil Conservation Service, 1962, Watershed work 

plan—Big Indian Creek Watershed Conservancy 

District: Lincoln, Nebr., U.S. Department of Agriculture, Soil Conservation Service.

———1965, Soil survey—Saunders County, Nebraska: 

Lincoln, Nebr., U.S. Department of Agriculture, Soil 

Conservation Service, 81 p., 68 pl.

———1966, Watershed work plan—Papillion Creek 

Watershed: Lincoln, Nebr., U.S. Department of Agriculture, Soil Conservation Service, 41 p.

———1968, Watershed work plan—Aowa Creek Watershed: Lincoln, Nebr., U.S. Department of Agriculture, 

Soil Conservation Service, 52 p.

———1971, Elkhorn River Basin, Nebraska—Water and 

related land resources: Lincoln, Nebr., U.S. Department of Agriculture, Soil Conservation Service.

———1972, Watershed work plan—South Fork Watershed: Lincoln, Nebr., U.S. Department of Agriculture, 

Soil Conservation Service, 45 p.

———1975, Nemaha River Basin, Nebraska—Water and 

related land resources: Lincoln, Nebr., U.S. Department of Agriculture, Soil Conservation Service.

———1981, Land resource regions and major land 

resource areas of the United States: Washington, D.C., 

U.S. Department of Agriculture, Soil Conservation 

Service Agricultural Handbook 296, revision of 1965 

edition, 156 p., 1 pl.

Swinehart, J.B., Dreeszen, V.H., Richmond, G.M., Tipton, 

M.J., Bretz, Richard, Steece, F.V., Hallberg, G.R., and 

Goebel, J.E., 1994, Quaternary geologic map of the 

Platte River 4o

 x 6o quadrangle: U.S. Geological 

Survey Investigations Map I–1420 (NK-14), scale 

1:1,000,000.
64 Streambed Adjustment and Channel Widening in Eastern Nebraska

U.S. Army Corps of Engineers, 1963, Design memorandum 

No. MSC–11—Channel improvement and levees thru 

Lincoln: Omaha, Nebr., U.S. Army Corps of Engineers, 26 p., 26 pl.

U.S. Army Corps of Engineers,1964, Flood plain information, metropolitan region, Lincoln, Nebraska, 

volume I—Salt Creek, Haines Branch, and Beal 

Slough: Omaha, Nebr., U.S. Army Corps of Engineers, 

36 p., 5 pl.

———1965, Review report—Platte River and tributaries—Interim report—Skull Creek Basin, Nebraska: 

Omaha, Nebr., U.S. Army Corps of Engineers, 31 p., 

8 app.

———1967a, Flood plain information, metropolitan 

region, Lincoln, Nebraska, volume III—technical 

appendix—Little Salt, Oak, Salt, and Stevens Creeks: 

Omaha, Nebr., U.S. Army Corps of Engineers, 5 app.

———1967b, Flood plain information— Papillion, Big 

Papillion, and West Papillion Creeks—volume 

I—Omaha metropolitan region, Nebraska: Omaha, 

Nebr., U.S. Army Corps of Engineers, 48 p., 20 pl.

———1968, Flood plain information— Little Papillion 

Creek and South Branch—volume II—Omaha metropolitan region, Nebraska: Omaha, Nebr., U.S. Army 

Corps of Engineers, 44 p., 11 pl.

———1970, Flood plain information, Big Blue River and 

Indian Creek, Beatrice, Nebraska: Omaha, Nebr., 

U.S. Army Corps of Engineers, 34 p., 11 pl.

———1980, Project maps, Omaha district, Status of river 

and harbor and flood control projects: Omaha, Nebr., 

U.S. Army Corps of Engineers, 121 p., 162 pl. 

———1989, Nebraska water resources development: 

Omaha, Nebr., U.S. Army Corps of Engineers, 43 p. 

———1993, Logan Creek—Pender, Nebraska—Reconnaissance report: Omaha, Nebr., U.S. Army Corps of 

Engineers [Section 205 reconnaissance study].

———1995, Southeast Nebraska streambank erosion and 

streambed degradation study: Omaha, Nebr., U.S. 

Army Corps of Engineers [Section 22 study], 67 p., 

5 apps., 4 pl.

———1998, Eastern Nebraska channel instability 

study—Stream classification: Omaha, Nebr., U.S. 

Army Corps of Engineers [Section 22 study], prepared 

for the Nebraska Department of Roads, 23 p., 1 pl.

———1999, Eastern Nebraska channel instability 

study—evaluation of bridge and culvert structures: 

Omaha, Nebr., U.S. Army Corps of Engineers 

[Section 22 study], 7 p., 9 apps.