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Changes in the Discharge of Suspended Sediment along the Missouri-Mississippi River System, 1940-2007
VIII ENES, Campo Grande, Brasil6 November 2008
John Moody and Bob Meade
IntroductionIntroduction
Bob MeadeBob MeadeJohn MoodyJohn Moody
Motivation: New Orleans after Hurricane Katrina
Photos: Smiley N. Pool and Michael Amsworth, WWLTV
Because deposition constructs barrier islands and wetlands that are protection for New Orleans
Remember that sediment deposition can be good
Some Candeleur Some Candeleur islands before islands before KatrinaKatrina
Two days after Two days after KatrinaKatrina
Summary of talkSummary of talk
1.1. Virtual tourVirtual tour
a.a. Landscapes along the Landscapes along the Missouri Missouri and and MississippiMississippi
b.b. Engineering activities along the Engineering activities along the Missouri Missouri and and Mississippi River Mississippi River SystemSystem
2.2. The mystery of the missing sedimentThe mystery of the missing sediment
Rainbow
Great Falls of the Missouri River River
Horseshoe
Black Eagle
Note: water has little sediment
Montana
Photo by Bob LindholmAirphoto-Jim Wark
Missouri BreaksMontana
Note: water has little sediment
Missouri BreaksMissouri Breaks
McClelland McClelland FerryFerry
Montana
Note: water has little Note: water has little sedimentsediment
Fort Peck DamFort Peck Dam
View: upriverView: upriver
Montana
Confluence belowConfluence below
Fork Peck DamFork Peck Dam
Rio Milk
Rio Missouri
Montana
Airphoto-Jim Wark
Note: water of the Missouri River has
little sedimentVista: abaixoVista: abaixo
Reservoir
Francis Case
Upriver from
Fort Randall Dam
in South DakotaMeade 2002
South Dakota
South Dakota
Fort Randall DamFort Randall Dam
on on Missouri RiverMissouri River
Yankton
South Dakota
Gavins Point DamGavins Point Dam
on on Missouri RiverMissouri River
Free-flowing Missouri
River begins here
View: downriver
from
Gavins Point Dam
YanktonNebraska
1.8 million t/a
Rio Missouri
Bodmer
Loess bluffsLoess bluffs
Omaha, Nebraska
Moody
Eppley Airport
1833
2002
OmahaNebraska
Missouri River in
Omaha, Nebraska
OmahaNebraska
26 million t/a
Nebraska
Kansas
Pile Dikes
Indian Cave Bend
View: downriver
Adapted from Funk and Robinson, 1974
-49%
Water
-41%Channels
-99%Islands
Channelization of Missouri RiverReduced source of sediment and increased storage in new
floodplains
Airphoto-Jim Wark
View: Upriver
Confluence of the Osage and Missouri
Missouri
Kansas
Photo: R. Stallard
Missouri
Storage of sediment behind dikes
Missouri River at Mile 189
View: Downriver
Missouri River at Hermann, Missouri
View: UpriverHermann
Missouri
88 million t/a
0 50 milhão t/a
Adapted from Parker, 1988, IAHS Pub. 174
Increase in suspended sediment discharge principle from loess landscape in Iowa
Iowa ~ 60 million t/a
Total = 88 million t/a
Missouri
Iowa
Confluence of the Missouri and Nishnabotna Rivers
MissouriYanktonYankton
HermannHermann
Wing Dams
or Rock Dikes
L-Dikes
View: below Hermann and upriver
Missouri
400 m400 m
Missouri
Sand dredging in the
Missouri River
near
St. Louis, Missouri
Missouri
IllinoisSt. LouisMissouri
IllinoisSt. Louis
Mississippi in
St. Louis, Missouri
97 million t/a
View: from the left bank
Missouri
Illinois
Mississippi River at
Cape Girardeau, Missouri
View: Upriver
Bank revetment
Mississippi River Mississippi River Upper Mile 51.0Upper Mile 51.0
Missouri
Illinois
L-Head dikeL-Head dike
Missouri
Illinois
Mississippi River Upper Mile 37
Alternate dikes
Missouri
Illinois
Mississippi at
Thebes, Illinois
View: downriver
The end of rocky
outcrops along the
banks
MissouriKentucky
Tennessee
Ohio Mississippi
Confluence of the Ohio and Mississippi
Rivers
View: downrivier
800 m
Mississippi River at Mile 388
Bank protection and trapping
of the sediment
Vegetation mat with rock protection at the
toe of the bank
Articulated concrete mat
Red River
Mississippi River
Atchafalaya River
Mississippi River
Tarbert Landing
Knox Landing
Simmesport
Old River
Outflow Channel
Navigation Lock
Low-sill
Hydropower dam
Auxiliary control
Arkan-sas
Louis-iana
0
10
20
Pro
fun
did
ade,
m
0 200 400 600 800 1000
Q = 21,000 m3 s-1
Lagura, m
Velocity, m s-1
0 2.01.0
Mississippi River
at Arkan-
sas
Louis-iana
Tarbert Landing, Mississippi
190 million t/a
Ohio
Missouri
Ohio
Missouri
Flux of water and suspended sediment from the Mississippi River Catchment
about 1980
Louis-iana
Lake Pontchartrain
Mississippi River Mississippi River flowing throughflowing through
New OrleansNew Orleans Louis-iana
Louis-iana
Mouth of theMouth of the
Mississippi RiverMississippi River
Gulf of MéxicoGulf of México
Barrier island Barrier island protection the coast of protection the coast of
New OrleansNew Orleans
The mystery of the missing The mystery of the missing suspended sedimentsuspended sediment
at at
Tarbert Tarbert LandingLanding
Integrated bag Integrated bag samplersampler
Significant decline after 1800
Suspended sediment discharge, million t/a
0 200 400
cerca de 1800 cerca de 1980cerca de 1800 cerca de 1980about 1800 about 1980
0
200
400
600
1950 1960 1970 1980 1990 2000
Water year
Cu
bic
km
per
yea
r
0
100
200
300
400
500
1950 1960 1970 1980 1990 2000
Mil
lio
ns
of
ton
s p
er y
ear
Sediment
Water
Mississippi River at Tarbert Landing
Sediment
Water
Mill
ion
t/a
km
3 / a
Water year in northern hemisphere (October through September)
190130
~ 370 million t/a
0
100
200
300
400
500
600
1950 1960 1970 1980
Water year
Millio
ns o
f to
ns p
er
ye
ar
One cause: Effect of damsclosed
110 million t/a40 million t/a
~ 150 million t/a
Mil
hões
t/a
0
100
200
300
1940 1950 1960 1970 1980
0
100
200
300
400
0
100
200
300
1940 1950 1960
Yankton
Omaha
Hermann
Tarbert Landing
Gavins Point Dam
Fort Randall Dam
CanadaUSA
Gulf of Mexico
Missouri River
Miss
issip
pi R
iver
Ohio River
0 500
kilometers
N
Amount entering between Omaha and Hermann
Water year in the northern hemisphere
0
200
400
600
1950 1960 1970 1980
Water year
Cu
bic
km
per
yea
r0
100
200
300
400
500
600
1950 1960 1970 1980M
illi
on
s o
f to
ns
per
yea
r
Tarbert Landing
Hermann
Omaha
Yankton
Sediment
Water
= Amount entering between Omaha and Hermann
km
3 / a
Sediment
Water0 50 million t/a
Adapted from Parker, 1988, IAHS Pub. 174
Hermann
Omaha
Milh
ões
t/a
Water year in the northern hemisphere
Other causes
Decline = - 23 million tons y-1
R2 = 0.52
Decline = - 3.3 million tons y-1
R2 = 0.47
0
200
400
600
800
1000
1930 1950 1970 1990 2010
Year
An
nu
al s
usp
end
ed-s
edim
ent
dis
char
ge,
m
illi
on
to
ns
Cu
mu
lati
ve R
evet
men
t o
r D
ike
Co
nst
ruct
ion
,km
0
400
300
200
100
An
nu
al s
usp
end
ed-s
edim
ent
dis
char
ge, m
illio
n m
etri
c to
ns
Cu
mu
lati
ve p
rote
ctio
n o
f th
e b
ank
or
cum
ula
tive
con
stru
ctio
n o
f d
ikes
, k
ilom
eter
s
Bank protection
dikes
year
~ 150 million t/a~ ??? million t/a
Other causes
Soil conservationUSDA Photo: Tim McCabe
~ 150 million t/a~ ??? million t/a~ ??? million t/a
Area, ha
Many small reservation in catchment of the
Missouri River
Effect: Change in the C-Q relation
Tarbert Landing
0
200
400
600
800
1000
200 300 400 500 600 700
Discharge, km3 y-1
Me
an
an
nu
al
su
sp
en
de
d-s
ed
ime
nt
co
nc
en
tra
tio
n,
mg
L-1
1950-1966
1967- 2007
C
Mea
n a
nn
ual
con
cen
trat
ion
of
susp
ende
d se
dim
ent,
mg
/ L
Q, Water discharge, km3 / a
Transport-limited system
Supply-limited system
~ 150 million t/a~ ??? million t/a~ ??? million t/a
Our Conclusions and ThoughtsOur Conclusions and Thoughts
1.1. Some of the missing sediment is behind Some of the missing sediment is behind the large dams. the large dams.
2.2. Structures like dikes and “Structures like dikes and “wing damswing dams”, ”, designed to protect banks store sediment designed to protect banks store sediment and prevent erosion of the sediment.and prevent erosion of the sediment.
3.3. Soil conservation probable has bee Soil conservation probable has bee effective in reducing the sediment effective in reducing the sediment discharge to the Missouri-Mississippi discharge to the Missouri-Mississippi River system.River system.
4. The 4. The Missouri-MississippiMissouri-Mississippi system has changed from transport system has changed from transport limited system to a supply-limited system. limited system to a supply-limited system.
5. Sediment deposition can be a problem 5. Sediment deposition can be a problem and sediment deposition can be and sediment deposition can be beneficial depending upon the human beneficial depending upon the human assessment of the situation..assessment of the situation..
6. We need to continue to collect good data 6. We need to continue to collect good data on sediment discharge. on sediment discharge.
Good data lives forever and are Good data lives forever and are fundament to modeling sediment fundament to modeling sediment transport. transport.
Models should only be used to synthesize the data. Models should only be used to synthesize the data.
In the world of “non-stationary”, continuity of data is critical. In the world of “non-stationary”, continuity of data is critical.
Our Conclusions and ThoughtsOur Conclusions and Thoughts
7.7. The scientific paper in press on this The scientific paper in press on this subject could not have been possible subject could not have been possible without data collected over a long without data collected over a long period of time (decades)period of time (decades)
8.8. We need to understand river We need to understand river ecosystems completely and not only in ecosystems completely and not only in terms of engineering structures. terms of engineering structures.
Our Conclusions and ThoughtsOur Conclusions and Thoughts
9. “Lean by listening and 9. “Lean by listening and observing the river—observing the river—each river is each river is different.”.different.”.
Our Conclusions and ThoughtsOur Conclusions and Thoughts
Obrigado por sua atenção.Obrigado por sua atenção.
Questões?Questões?