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Title: Streambank stabilization, the old and the new


1
Streambank stabilization, the old and the new!
L-head hockey-stick THINGY, a Ron Redman
structure
The old tire on a cable trick!
2
Politically Incorrect Bank Protection
Methods
  • Old car bodies (Detroit Riprap)
  • Rubbish and garbage (appliances, etc.)
  • Building materials (old roofing, bricks, etc.)
  • Old farm machinery
  • Railroad cars
  • Broken concrete
  • Large objects in small waterways

3
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4
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5
Carhenge War Eagle Creek, AR
6
Always try get a good gradation on that Detroit
riprap Car-henge, War Eagle Creek, AR
7
Solomon River, KS
8
Railroad car in Sun Valley, UT
9
Slab-shaped materials do not self-adjust (launch)
well, note the steep slope of this pile
Arkansas River, KS
10
Ft. Worth, TX.
11
Carbondale, IL
12
The rock or concrete must have a ratio of the
longest axis (A-axis) to the shortest axis
(C-axis) of less than 3.5 to 1.
13
Cahokia Creek, IL
14
Ashtabula River, OH
Concrete appears to be too high on bank to do
much good
15
When the concrete-lined channel breaks up
it is not pretty, Vensel Creek, Tulsa, OK
16
Almost Every Bank Protection Technique You Have
Ever Heard Of !!
  • RESISTIVE
  • REDIRECTIVE
  • PROPRIETARY
  • BIOENGINEERING
  • COMBINATIONS OF THE ABOVE

17
Resistive Bank Stabilization Methods
What is the project goal here? Western Iowa
18
TOO MUCH STONE!! WE ARE LOOKING TO ACHIEVE
BALANCE
19
Resistive Bank Stabilization Methods
  • (usually continuous, applied directly on the
    bank, or toe, or both, offers resistance to river
    or stream forces, some methods can self-adjust,
    others are rigid)
  • Natural features (rock outcroppings, blue clay,
    etc)
  • Riprap and Boulder Blankets (bank paving)
  • Grouted Riprap
  • Sack Revetments
  • Soil Cement
  • Root Wads
  • Log Revetment
  • LUNKERS
  • Trenchfill (setback revetment)
  • Windrow Revetment
  • Longitudinal Peaked Stone Toe Protection (LPSTP)
  • Longitudinal Fill Stone Toe Protection (LFSTP)

20
Inert Material Bank Protection Structures(Logs,
Riprap, Concrete, Stone, Rubble, Etc.)
  • Furnish a stable, solid substrate for benthic
    macroinvertibrates, important in areas where
    solid substrate is in short supply.
  • Increase the underwater surface area.
  • Provide substrate for spawning for some fish
    species.
  • Interstices provide shelter and cover for aquatic
    lifeforms (both juvenile and adult).
  • Offer aquatic lifeforms refugia during high water
    events.
  • Can aerate water and provide water surface
    disturbances (which provide a type of cover for
    fish).
  • Reduce fine particle load by reducing erosion
    (possibly reducing turbidity and improving WQ).

21
Riprap and Boulder Blankets, Other
Interesting Bank Paving Things
Looking DS at 9-ft long gravel-filled bags
adjusting to removal of toe foundation material,
Sag River, Alaska
22
You should always consider how a method
could fail (failure modes) perform a
risk analysis of the possibility of that
happening in your project
23
Hand-Placed stone bank protection on the Missouri
River, circa 1925-30
Stone gradation defined as One-man stone
24
Similar hand-placed stone revetment on the
Mississippi River, constructed in the 1930s,
photographed (with fishermen) in 1996
25
Plated riprap, smooth surface for better flow,
replicates old hand-placed riprap
From McCullah
26
Stacked stone walls will only stay stacked with a
deep foundation
Cobbs Creek, Philly, photo by Charles Sutphen
1/26/2006
27
Typical riprap placement on the bank of the
Ohio River, Evansville, IN Aug 2003
28
Older riprapped bank with volunteer vegetation,
Ohio River (directly across river from previous
picture)
29
VALID ENVIRONMENTAL CONCERNS WITH CERTAIN
CONSTRUCTION MATERIALS
  • Have the agency/persons with concerns annunciate
    those concerns in conceptual terms (not I hate
    stone!)
  • Then determine if VALID concerns can be mitigated
    (example thermal pollution from stone (heating
    up), can we shade areas where stone will be
    placed)

30
Riprap blanket to top bank with no planted
vegetation, two years after installation, note
intense volunteer vegetation, looking DS South
Fork Spring River, AR.
31
S. Fork Spring River, AR, same bend as previous
slide, after first growing season
32
Jackson, MS
33
Looking DS at new construction (2002) of riprap
blanket at Walter Wests farm, Bayou Pierre,
Dentville, MS
34
Soil-choked riprap, unknown stream, Lancaster, PA
35
Looking DS at Sag River, Alaska. Toe scour with
rock on shiny and slick woven geotextile filter
resulted in over-launching of stone exposure of
geotextile
36
Thoughts on Filters
  • A filter has at least three tasks
    prevent loss of underlying fine bank materials
    due to piping, extrusion, or erosion allow water
    to drain from the bank thus preventing the
    buildup of excessive hydrostatic pressure and to
    prevent bank stabilization materials from sinking
    into the underlying substrate. A trained soil
    scientist, geologist, and/or geotechnical
    engineer is needed to perform an analysis of the
    stability and erodability of bank materials and
    determine what, or if any filter is required.

37
Different Types of Filters
  • Self-filtering stone - Designed with a specific
    gradation that has a component that acts as a
    granular filter. Typically 10 to 15 of the
    gradation is either less than 4 inches in
    diameter, or less than one pound in weight,
    depending on how the stone is specified. When
    placed on-site the smaller stones fall through
    the interstices and cover the substrate,
    essentially acting as a granular filter.
  • Granular filters - Progressively larger diameter
    layers of (possibly) sands, gravels, and/or rock.
  • Geotextile filters Non-Woven - has a thickness,
    similar in appearance to felt, dull finish,
    fibers can be seen but don't form a pattern.
  • Geotextile filters Woven - slick and shiny, has
    a discernable weave (a pattern similar to a
    cotton shirt), designed with a specific size of
    opening to allow the passage of water, but not
    the underlying bank material. When looking
    through a section of used filter light should be
    visible. If no light can be seen the filter has
    been "blinded", in other words the filter has
    been clogged by the bank material. It can also
    be blinded by deposition from the stream side.
  • Is a filter needed?? - gravels, cobbles, bedrock
    and some clays usually do not require a filter.
    Always always consult with a learned geotechnical
    expert!!!

38
A non-woven filter not in intimate contact with
the underlying substrate
39
Woven Geotextile Filter Fabric
A steep slope, combined with riprap on a slick
surface, can lead to problems!
Ohio River
40
Woven filter, not blinded, sunshine visible
through weave. Woven filters can sometimes be
blinded from either the river or bank side
41
Arkansas
Filter fabric could prove problematic with
over-launching of stone (shown), interferes with
root architecture, plus roots can run on filter
open up overlaps
42
7 year old riprap without filter fabric allows
for natural plant colonization. Spring River, AR
43
Self-Adjusting, Self-Filtering Stone
  • Depending on size, angularity, and gradation,
    stone can be neither, either, or both!!
  • Self-Adjusting Stone
  • Stone must be well-graded (from coarse to fine)
    so that it has the ability to "launch", or
    self-adjust into, and armor, scour holes formed
    on the streamward side, and/or stream end, of a
    river training structure.
  • Charlie Elliott says a good rule of thumb in
    Mississippi sand-bed streams CAUTION this might
    not apply equally well to every stream in the
    world is that one ton of rock per linear ft will
    armor approximately three ft of scour
  • Self-Filtering Stone
  • A soil analysis should always be performed to
    determine stability and erodability of bank
    materials and whether a filter material, (either
    granular or synthetic) is required.
  • A self-filtering stone that has worked well on
    the Mississippi River, and numerous other rivers
    and smaller streams (acting as a granular filter
    to prevent loss of underlying bank material) has
    10 to 15 of the gradation either less that 4
    inches in diameter, or less than one pound in
    weight, depending on how the stone is specified.

44
An ugly pile of rock!! Median of I-220, Jackson
MS. Self filtering, in fact too many fines, but
steep angle of repose shows that stone will not
self-adjust. This is due to the lack of
medium-sized stone (stone is not well graded).
45
Analyze gradation, amount of fines, look at
pile side slopes (flatter is better). Climb the
pile, if it moves that is the stone you need.
This is well graded stone, note flat angle of pile
46
Medina Quarry, TX.
Blocky rock will not adjust, but can be used in
interesting ways, including end-to end
compression, or in a stacked configuration.
47
Better looking stone, note flat pile, Medina
Quarry, TX. We mixed the two piles of stone
from the previous picture to come up with a
well-graded stone that will self-adjust.
48
Well-graded stone, but few fines, for Skunk River
project, Denmark, IA. To effectively use this
stone we installed a granular filter of 1 to 3
inch stone, then installed this stone.
49
Key trench for Bendway Weir, Skunk River, Iowa.
Granular filter (1 to 3 inch stone) is installed,
then overtopped with key stone.
50
A SHORT TALK ABOUT ROCK
  • QUARRIES - distance from project, quality of
    rock, price, ability to deliver amount of rock
    needed (14 to 16 tons per truckload for tandem
    axle trucks is typical)
  • COMPOSITION - granite, limestone, basalt,
    dolomite, sandstone, etc.
  • HARDNESS - varies from quarry to quarry and
    sometimes within the quarry
  • SHAPE SIZE - block shaped rocks will lock
    together, look at the shape of the pile of rock
    at the quarry, climb the pile to see how well
    rocks will roll downhill, measure for size
    (B-axis) and visually access gradation, compare
    quarrys gradation curves to standard gradation
    curves.
  • GRADATION - well graded (poorly sorted) is best
    (largest, then smaller, smaller, smallest with
    the fine component that will work as a granular
    filter)
  • WEIGHT - varies, for limestone 1.5 tons per cubic
    yard is good for estimation purposes (115 lbs/cu.
    ft.)
  • VOLUME ESTIMATES - estimate amount needed, then
    add 10 to 15 percent
  • SPECIFICATIONS - Can be "made" to custom
    specifications or to common specs HAUL RATES -
    Stone weighing over 400 pounds must be
    transported in steel bodied trucks, or a bedding
    layer of gravel is placed in aluminum bodied
    trucks. Haul rates are usually multiplied 1.5
    or 1.75 times the base haul rate.
  • WEATHERING - look for examples in the quarry /or
    local stream or highway projects, check rocks
    lining the entrance to the quarry

51
Eudora bend, Kansas River, KS. End dumping like
this will sort out even a well-graded stone!!
Dont do this!!
52
Differential weathering turning big stone to
gravel, Dome Pipeline Crossing, Minnesota River,
Mankato, MN
53
Gradation curves courtesy of Vicksburg District,
COE
54
Gradation curves courtesy of Vicksburg District,
COE
55
Gradation curves courtesy of Vicksburg District,
COE
56
Gradation curves courtesy of Vicksburg District,
COE
57
BEDLOADCONSTRUCTION STONETROUBLE, ARKANSAS
58
"SHOT ROCK" (Also called quarry run, or
ungraded stone)
  • "Shot" rock, also called "quarry run" stone, is
    an ungraded stone blasted at the quarry with the
    only specification being a maximum (top) size or
    weight. No specific gradation, or amount of
    "fines" is specified.
  • The amount of usable stone depends on the skill
    and knowledge of the blasting technician.
  • Advantages Cheaper, usually close to 1/2 the
    cost of graded stone. The ungraded
    characteristics of the stone can result in
    increased void spaces (interstices), possibly
    providing within-channel refugia for aquatic
    species (especially juveniles).
  • Disadvantages A truckload of rock might be all
    top size or dust. Inspector's knowledge/experienc
    e critical when deciding where, or if, a load of
    stone should be placed/used. Some material might
    be wasted. This stone is typically NOT
    self-adjusting. It might or might not be
    self-filtering and could vary by the truckload.

59
Gradation can be varied for environmental purposes
Hat for scale
60
GROUTED RIPRAP, MS.
61
Waterways Experiment Station, Vicksburg, MS.
62
BEWARE OF FOUNDATION DEPENDANT BANK
STABILIZATION METHODS !!!
  • If the foundation is erodable, the bank
    protection method might have to be toed down
    (excavated) to the level of maximum anticipated
    scour (at least below the thalweg elevation)

63
Grouted riprap undercut by flow, Clear Creek,
Manhattan, KS.
64
Grouted riprap providing great undercut bank
habitat, AR
65
Canadaway Cr., Arkwright, NY. 11/2/2005
Non-adjusting riprap does not adjust very well,
upper bank stone tends to hang, even on a
slippery woven filter
66
SACK REVETMENTS
67
From Dr. Doug Shields
68
Sudden channel expansion with resultant erosion,
Thompson Creek, San Vicente, CA (2002)
69
SOIL CEMENT BANK STABILIZATION
70
An arid regions technique, Soil Cement bank
protection seen here on the New River at Olivia
Avenue, Phoenix, AZ
71
ROOT WADS
When using big wood you always have to ask, if
it gets loose what does it jam up on? If it
stays put how much other wood will get stuck on
it? And, how long will it last?? Sulphur Creek,
Redding, CA
72
From www.E-senSS.com
73
Charles Schwabs stream, Missoula, MT.
74
Guadalupe Creek, CA
75
These rootwads are too high!!
76
LUNKERSLittle Underwater Neighborhood
KeepersEncompassing Rheotactic Salmonids
  • (Rheotactic - fish that prefer to face into the
    current)
  • A LUNKER structure, first developed
    and used in Wisconsin, is an engineered,
    undercut-bank structure designed to provide
    habitat for fishes while providing bank
    stability. A LUNKER is typically 8 ft long, 1 to
    2 ft tall, and 3 ft deep, constructed of hardwood
    (or concrete or plastic wood if numerous wet-dry
    cycles are anticipated), with an open front and
    ends. The toe of the outer bank of the stream is
    leveled, then the LUNKER is placed on the level
    bed and 0.5 inch, x 7 ft long sections of rebar
    are driven through pre-drilled holes and into the
    stream substrate, anchoring the LUNKER to the
    stream bed. The area bankward of the LUNKER is
    filled with riprap, and either large stones, or
    soil and a circular coir fiber roll are
    positioned on top of the LUNKER.
  • Concrete-roofed LUNKERS can be used as fishing
    platforms in handicapped-accessible facilities.

77
Designed to provide an engineered undercut bank,
in addition to bank protection
78
Photo Ron Redman
Natural undercut bank, North Sycamore Creek, AR
79
Original Wisconsin LUNKER design
80
Typical LUNKER Design Detail
81
Typical LUNKER Installation (can be modified
for specific applications)
82
Installing LUNKERS in IL.
Mini case study 1 of 4
83
Mini case study 2 of 4
84
Mini case study 3 of 4
85
Mini case study 4 of 4
86
Rapid Creek, Rapid City, SD, installed 1983,
photo 1996
87
Looking DS, Installing LUNKERS, Brush Creek, 1997
88
Brush Creek, looking DS at low-water road
crossing, LUNKERS with coir fiber roll on top,
immediately US of crossing at toe of LDB,
installed 1997, pix shot Aug 2003, most had
filled in with sediment.
89
Brush Creek, looking DS, LUNKERS at toe of LDB
with rocks on top, installed 1997, photograph Aug
03
90
LUNKERS FOR 18 MILE CREEK
  • For the 18 Mile Creek salmon stream restoration
    project, Newfane, NY) 6 LUNKERS were constructed
    out of lumber (oak) and one from stone
  • Wooden LUNKERS were 8 ft long, by 2 ft wide, with
    an 18 inch tall opening
  • Approximately 54 ft of LUNKERS were placed on
    bedrock immediately adjacent to the Great Wall of
    Newfane, where sufficient depths and currents
    were available.
  • The single stone LUNKER was integrated into the
    Great Wall, and the lumber LUNKERS were built
    upside-down and locked under the Great Wall for
    long-term stability. Stones also covered the
    tops of the wooden LUNKERS

Mini case study 1 of 9
91
EIGHTEENMILE CREEK, NEWFANE, NY SUBURBAN,
GRAVEL-COBBLE BED, POOL-RIFFLE-POOL REGIME
STREAM IN A V-SHAPED VALLEY
Unloading a timber LUNKER
Mini case study 2 of 9
92
It took several hours to place the first LUNKER,
then about one hour per LUNKER thereafter (total
of 6 placed)
Mini case study 3 of 9
93
Mini case study 4 of 9
94
Timber LUNKER partially covered with flat stones
Mini case study 5 of 9
95
All wooden LUNKERS anchored under stones, and
then covered with another set of stones
LUNKER
Mini case study 6 of 9
96
Looking DS
48 linear ft of wood LUNKERS hidden under the wall
The single stone LUNKER
Mini case study 7 of 9
97
Mark Seider and Amy Fisk on the single stone
LUNKER
Mini case study 8 of 9
98
Working a big fish while Hydraulic Cover stones
are also working hard She lost this one!
Mini case study 9 of 9
99
LUNKER Failure Modes
  • Many fill in with sediment
  • Some are left high and dry
  • Scour of foundation materials resulting in
    collapse
  • Functioning LUNKERS require
  • Positioning in higher velocity areas typically on
    the outside of a bend
  • Sufficient velocities to scour sediment from
    LUNKER
  • Foundation might need reinforcement
  • Low-flow water surface elevation should be on
    header board

100
Log LUNKER engineered undercut bank, bank
stabilization aquatic habitat restoration,
urban stream, Johnson Creek, Portland, OR.
Not a flow-thru design.
101
Looking DS _at_ a crib wall on the left vegetated
geogrid DS
ELBO CREEK-MANHATTAN KS-PIX FROM DERRICK 4-7-2009
102
SELF-ADJUSTING METHODSIF THE BED OF THE STREAM
IS BEDROCK, SELF-ADJUSTING METHODS ARE USUALLY
NOT NEEDED. NON-ADJUSTING METHODS SHOULD BE
KEYED INTO THE BED AT LEAST TO THE THALWEG
INVERT, AND PROBABLY TO THE MAXIMUM ESTIMATED
SCOUR DEPTH
103
TRENCHFILL REVETMENT, RED RIVER, LA.Also
called Setback Revetment
104
Red River, LA.
105
(No Transcript)
106
WINDROW (SET-BACK) REVETMENT
107
WINDROW ON THE KANSAS RIVER, Eudora Bend, KS
108
A TRENCHFILL TWEENER
109
LONGITUDINAL PEAKED STONE
TOE PROTECTION LPSTP
  • Description A continuous stone dike placed
    longitudinally at, or slightly streamward of, the
    toe of the eroding bank. Cross-section is
    triangular. The LPSTP does not necessarily
    follow the toe exactly, but can be placed to form
    a "smoothed" alignment through the bend.
    Smoothed alignment might not be desirable from
    the environmental or energy dissipation points of
    view . Amount of stone used (1 ton/ lineal ft, 2
    tons/ft, etc.) depends on depth of scour at the
    toe, estimated stream forces (impinging flow) on
    the bank, and flood durations and stages.
  • Tie-backs are short dikes connecting the LPSTP to
    the bank at regular intervals. Tie-backs are
    usually the same height as the LPSTP or elevated
    slightly toward the bank end, and are keyed into
    the bank. If tie-backs are long they should be
    angled upstream to act as bendway weirs.

110
Longitudinal Peaked Stone Toe Protection
Flow
Inner bank
Upstream key
Outer bank
LPSTP (black line)
Downstream key
Tie-backs (blue lines) will connect the LPSTP to
the key. The key, sometimes called the key root,
is dug into the bank.
Mid-project keys (red lines) are perpendicular to
high flow connect the tie-back to the bank
Modified from www.E-SenSS.com
111
Longitudinal Peaked Stone Toe Protection (LPSTP)
As-built
After a couple of high flow events stream has
scoured at the toe stone has self-adjusted
Sediment has deposited landward of the LPSTP
112
Johnson Creek, MS. Pre-project rapidly eroding
near-vertical bank rural, sand bed, slope lt 1,
pool-riffle-pool, meandering, incised
Mini case study 1 of 3
113
Johnson Creek, MS. As-built protection consists
of Longitudinal Peaked Stone Toe protection
(LPSTP) applied at 1 ton/ lineal foot
Mini case study 2 of 3
114
Johnson Creek-LPSTP one year later (note
volunteer willow growth)
Mini case study 3 of 3
115
Functions and Attributes of Longitudinal
Peaked Stone Toe Protection
  • Resists the erosive flow of the stream, only
    stabilizes the toe, does not protect mid and
    upper bank areas.
  • "Smoothed" longitudinal alignment results in
    improved flow near toe.
  • Success depends on ability of stone to launch
    into scour hole.
  • Bank grading is not needed (existing vegetation
    is not disturbed).
  • Weight of stone (loading of toe) might resist
    some shallow-fault geotechnical bank failures.
  • Captures alluvium upslope failed material on
    bank side of structure.
  • Good where outer bank alignment makes abrupt
    changes, where the bank must be built back out
    into the stream (realignment of channel, or
    construction of a backfilled vegetative bench or
    terrace for habitat improvement and/or velocity
    attenuation), where a minimal continuous bank
    protection is needed, or where a false bankline
    is needed.
  • Works well in combination with other methods
    (Bendway Weirs, or bioengineering within the
    stone joint planting, Bent willow poles or
    immediately behind stone Live Siltation, Living
    Dikes, in mid to upper bank areas brush
    layering, Slit Brush Layering, Live Staking,
    rooted stock or container plants).

116
Longitudinal Peaked Stone Toe Protection
installed 1977, picture taken Sept 2003 at
Batapan Bogue, Grenada, MS. LPSTP has launched
as intended (note steep angle of repose), armored
the scour hole as expected, mature vegetation
is assisting with overall bank stability
117
CASE STUDY- Hickahala Creek Pipeline
Protection Project at milepost 347.64Tate
County, Senatobia, MS Constructed Sept. 2003
Longitudinal Peaked Stone Toe Protection
LFSTP with upper bank paving
118
SELF-ADJUSTING, SELF-FILTERING STONE
Original cross-section, note angle of repose
11.5 to 11.25
Reduced height of protection
Undercut launched, original height of
protection is reduced
Undercut angle of repose is steeper than original
119
Looking US at the entire stream trying to flow
underneath the exposed pipeline, the first bend
downstream of a long straight stretch is hard to
repair, the water does not want to turn!!! This
stream put sediment 1,000 ft in a straight line
out into the farmers field.
120
Our area of interest.
Flow attack angle
121
LPSTP bank paving totaled 8 tons/ft on this
bank!
LPSTP toe
Bank Paving
September-26-2003
122
Hickahalla Creek, Senatobia, MS. Constructed Sept
2003. Looking US at impinging flow impact zone.
Note steep angle where LPSTP was undercut
launched (self-adjusted). Several years later
this bank is still stable vegetated
April 2006
123
Note steep angle where LPSTP was undercut and
launched (self-adjusted)
Original angle of repose
Launched angle of repose
124
4 years after construction, very stable, veg
growing well
LOOKING US, JULY 2004
March 2007
125
Produced by John McCullahs firm Salix Applied
Earthcare
From www.E-SenSS.com
LIVE SILTATION landward of LPSTP
126
Constructed terraces with specific species
vegetation (or combos) on each bench
Live siltation (willow)
Backfill
Original bank
LPSTP
Longitudinal Peaked Stone Toe Protection (LPSTP)
Constructed of a well-graded, self-adjusting,
self-filtering stone (no filter fabric
underlayment)
127
THE KEY TO STABILITY IS THE KEY (stream
should be on the other side of the wooden retard)
128
A bank protection project should start
end in stable (usually depositional) areas.
129
A key has one main function to connect bank
protection (or a river training structure) to the
rest of the world, not let the river flank
(get behind) the improvement or protection works.
130
20-30 degrees
Longitudinal Peaked Stone Toe Protection
Flow
Inner bank
Upstream key
Outer bank
20-30 degrees
LPSTP (black line)
Downstream key
Both the upstream downstream keys should be
angled 20 to 30 degrees to high flow. All keys
are vegetated and soil choked
Tie-backs (blue lines) will connect the LPSTP to
the key. The key, sometimes called the key root,
is dug into the bank.
Mid-project keys (red lines) are perpendicular to
high flow connect the tie-back to the bank
Key design for continuous bank protection,
modified from www.E-SenSS.com
131
On the landward end (away from the stream), all
keys need to tie into roughness, or a higher
elevation, or hopefully both!! Elevation can be
determined by flow (Q-10, Q-100, etc.)
132
Looking US on Harland Creek, Tchula, MS at smooth
LPSTP (1.5 tons/ft) with correctly angled
downstream key with deposition (free bank
protection) right where the photographer is
standing. Installed Aug 1993.
133
Keys can be constructed of a large blocky stone
that will not adjust, or of a self-adjusting
(well-graded), self-filtering stone. Amount of
stone should equal or exceed the amount of stone
used per ft in the bank protection or river
training structure. A granular filter might be
needed.
134
The key itself should be heavily vegetated with
adventitious rooting poles or rooted stock plants
so as to slow velocities over the key. Slow
water on the overbank means less chance of
flanking. Vegetation is designed to act like a
Living Dike can be closely spaced adventitious
rooting poles, or rooted stock plants, or both.
In some cases the length of the key can be
extended with vegetation alone.
135
The upstream key on Chenunda Creek, Wellsville
NY. The key is angled 30 degrees to dominant
(high) flow. This same angle should be used for
the downstream key.
136
Construction 9/19/2006. Looking US. Digging the
US key at a 30 degree angle to where high flow
would attack the project
  • Pix by Derrick

137
Looking US. Hoe placing big stone (NYS DOT
heavy) in US keyway. Medium stone will be added
as a choke.
  • Pix by Derrick

138
Construction 9/20/2006. Looking at angle of key
to stream flow. More stone will be added then
soil choked so the landowner can grow a lawn.
High flow angle
Key angle
  • Pix by Derrick

139
Dump truck load level full of Sandbar Streamco
Willow, Ruby Red osier dogwood, (1,500 poles
total).
  • Pix by Derrick

140
A MID-PROJECT KEY ON CHENUNDA CREEK
Vegetated soil-choked stone key is
perpendicular to high flow ( the bank)
141
Detail for key
Cross-section for keyway
Flow
142
Detail for key
Flow
Place granular filter, or use a self-filtering
stone
143
Detail for key
Place Willow Poles against one or both sides of
trench
Flow
144
Construction 9/19/2006. Digging a mid-project
key perpendicular to the bank. Some veg (willow
poles) in place
  • Pix by Derrick

145
Detail for key
Place stone in trench
Flow
146
Construction 9/19/2006. Looking at key. Butt
ends of willow dogwood poles down deep.
  • Pix by Derrick

147
Detail for key
Choke stone with gravel-cobble (white areas)
water in
Flow
148
Detail for key
Backfill and overfill with native soils, then
compact (some settling will still occur)
Flow
149
Construction 9/21/2006. Key stone is now
soil-choked.
  • Pix by Derrick

150
Detail for key
Seed
Flow
DONE
151
13 MONTHS LATER-low flow. Veg in key is robust.
  • Pix by Derrick 10/15/2007

152
2.75 YEARS LATER-Lush growth from unrooted poles
on mid-project key.
2 YEARS 9 MONTHS AFTER CONSTRUCTION-CHENUNDA
CR.-DERRICK 6-18-09
153
VEGETATION IN KEY ACTING AS A LIVING DIKE
ON ONONDAGA CREEK (perpendicular to high
flow)
154
Looking toward stream. Key vegetation is 4 ft
deep. Key stone buried to right of veg.
Onondaga Creek _at_ Nichol Road Bridge, LaFayette,
NY project planted 5-15-2007
Pix by Derrick
155
July 10, 2008. middle of second growing season
Key vegetation is over 7 ft tall. Willow
dogwood. Will act as a Living Dike.
Onondaga Creek-Year 2
Pix by Derrick
156
DESIGN CONSIDERATIONS FOR LPSTP KEYS
  • LPSTP must be deeply keyed into the bank at both
    the upstream and downstream ends and at regular
    intervals along its entire length. Charlie
    Elliotts spacing rules-of-thumb for keys in
    flat-sloped sand bed water bodies 50 to 100 ft
    intervals on smaller streams, 1 to 2 bankfull
    widths on larger waterways.
  • Keys at the upstream and downstream ends of LPSTP
    should not be at a 90 degree angle to the LPSTP
    structure, but at 20 to 30 degrees to HIGH FLOW.
  • Keys should go far enough back into the river
    bank so river migration will not flank the key
    and the LPSTP.
  • Keys should be vegetated if possible. Key length
    can be extended with vegetation in some cases.
  • Volume of material per ft of key should equal or
    exceed the volume of material per ft in the LPSTP
  • Minimum key width should be two times the D-100
    of the stone used

157
Functions and Attributes of Longitudinal
Peaked Stone Toe Protection
  • Resists the erosive flow of the stream, only
    stabilizes the toe, does not protect mid and
    upper bank areas.
  • "Smoothed" longitudinal alignment results in
    improved flow near toe.
  • Success depends on ability of stone to launch
    into scour hole.
  • Bank grading is not needed (existing vegetation
    is not disturbed).
  • Weight of stone (loading of toe) might resist
    some shallow-fault geotechnical bank failures.
  • Captures alluvium and upslope failed material on
    bank side of structure.
  • Good where outer bank alignment makes abrupt
    changes, where the bank must be built back out
    into the stream (realignment of channel, or
    construction of a backfilled vegetative bench or
    terrace for habitat improvement and/or velocity
    attenuation), where a minimal continuous bank
    protection is needed, or where a false bankline
    is needed.
  • Works well in combination with other methods
    (bendway weirs, or bioengineering within the
    stone joint planting, Bent willow poles or in
    mid to upper bank areas live siltation, brush
    layering, live staking, rooted stock).

158
Longitudinal Peaked Stone Toe Protection
installed 1977, picture taken Sept 2003 at
Batapan Bogue, Grenada, MS. LPSTP has launched
as intended (note steep angle of repose), armored
the scour hole as expected, with mature
vegetation assisting overall bank stability
159
Over-launching on S. Fork Tillatoba Creek,
installed 1972, photographed 1998
160
Brushy Creek, IL. Looking DS. This is about
0.75 ton/ft of self-adjusting stone, which is
about the minimum that can be used. Note that
contractor worked from top bank really beat up
a lot of the good bank vegetation.
Pix by Wayne Kinney
Minimal LPSTP
161
Transitioning from LPSTP to full bank paving
Looking DS on Harland Cr. Tchula, MS, very smooth
transition in the downstream direction from one
ton/ft LPSTP to full bank paving
162
COMBINATIONS OF RESISTIVE, REDIRECTIVE,
BIOENGINEERING METHODSCASE STUDY- Cattaraugus
Creek _at_ Savage Road, Sardinia, New
YorkConstructed October 2004A FALSE
BANKLINE USING DUG-IN LFSTP WITH LIVE
SILTATION, A VEGETATED FLOODPLAIN BENCH
BENDWAY WEIRS
163
LFSTP False Bankline Created Floodplain Bench
Slit-trench plantings
Living Dikes
Pole plantings
Live Siltation
Original bankline
Backfill
LFSTP
On gravel-cobble streams the LFSTP can be dug
below stream invert, hard to do in sand
164
LIVE SILTATION BEHIND OVER THE TOP OF THE
LONGITUDINAL FILL STONE TOE PROTECTION
(LFSTP)
165
The secret to success with willows is to get the
basal ends down into the water, or the vadose
zone. Looking US. Live Siltation willows are
behind over the top of the LFSTP.
166
Looking US at Live Siltation behind LFSTP,
placing fine-grained material from DS end of
opposite bank point bar (growing medium for Live
Siltation).
167
Looking US at completed project with all LPSTP
with Live Siltation, Rock Vane, Bendway Weirs and
the floodplain bench in place
168
Jumping a year ahead, looking US at the same
floodplain bench, note good veg growth. Aug 29,
2005
169
Looking DS at Live Siltation, it will provide
shade quickly over water and LFSTP.
170
Looking DS at Live Siltation behind LFSTP, Catt
Creek at Savage Road.
171
Live Siltation Aug 29, 2005, end of first growing
season after installation. Note 2 Bendway Weirs
172
Design Rules-of-Thumb for LPSTP(developed from
experience in Mississippi on incised, relatively
flat-sloped, sand bed streams)
Page 1
  • Dr. Dave Biedenharn recommends that if you have
    never used LPSTP in your area, get a designer
    with LPSTP experience to design your first
    project!
  • If there is the opportunity to build a
    demonstration project do so. Either test
    different heights of LPSTP in a number of similar
    bends, or for testing in a single bend start at
    the upstream end with a reasonably tall 50 ft
    long section of LPSTP (take the amount of stone
    calculated from consideration 2 and add 4 ft to
    the height). Continue in the downstream
    direction reducing height in 1 ft increments
    until an unusually small amount of stone is used
    (3 ft below low-flow water surface elevation for
    example, or below the vegetation line if one
    exists). After a reasonable time and at least
    two flood or long-duration high-flow events the
    sections that failed will provide some guidance
    for the minimum effective crest height
  • At this time, no specific design criteria exists
    that relates the crest elevation of LPSTP to the
    channel forming discharge, effective discharge,
    or dominant discharge.
  • One ton of LPSTP/per lineal ft is approx. 3 ft
    tall (using limestone_at_110lbs/cu ft)
  • Two tons/per lineal ft is approx. 5 ft tall
    (height calculations from Vicksburg Dist.)
  • Three tons of LPSTP/per lineal ft is approx. 6 ft
    tall 7.5 tons is 9.5 ft tall
  • Four tons of LPSTP/per lineal ft is approx. 7 ft
    tall 10 tons is 11 ft tall
  • Six tons of LPSTP/per lineal ft is approx. 8.5 ft
    tall 14 tons is 13 ft tall

173
Design Rules-of-Thumb for LPSTP(continued)
Page 2
  • Maximum stone size and correct gradation can be
    generated using any of many available riprap
    sizing design programs (ChanlPro, WEST
    Consultants RIPRAP, etc.)
  • Consideration 1 The minimum amount of stone
    that would have a launchable component to any
    degree, would be ½ to ¾ of a ton of stone per ft.
    The ½ ton/ft amount would provide a triangular
    section of stone approximately 2 ft tall.
  • Consideration 2 Maximum scour depth in the
    bend should be numerically calculated, or
    estimated from field investigations (depths might
    be underestimated due to in-filling of scour
    holes during the falling side of the high-water
    hydrograph). Typically 1 ton of stone will
    protect against every 3 ft of scour. Amount of
    stone required to amour the estimated maximum
    scour depth should be calculated, and a factor of
    safety added. If scour is greater than 3 ft
    (as calculated in Consideration 2) then a
    Longitudinal Fill Stone Toe Protection (LFSTP)
    should be considered.

174
Design Rules-of-Thumb for LPSTP(continued)
Page 3
  • Consideration 3 If there is a vegetation
    line, the mature well-established section of the
    veg line should be analyzed, and if
    Considerations 1 and 2 are met, then the veg.
    line elevation would be the absolute minimum
    crest elevation. But, since plants immediately
    above the vegetation line are typically not very
    robust, and there is no factor of safety
    included, this minimum crest height should be
    increased at least 2 to 4 ft or more, dependant
    on situation.
  • Consideration 4 The height of the bends
    opposite bank pointbar bench should be analyzed.
    If the point bar bench height is taller than the
    crest of the designed LPSTP, then consideration
    should be addressed as to whether the LPSTP
    height should be raised to a height equal to, or
    taller than, the pointbar bench elevation.
  • Scour estimation and various methods of
    positioning launchable stone are discussed in
    CORPS Engineering Manual EM-1601, Chapter 3

175
False Banklines using LPSTP(small stream)
  • Useful when thalweg requires realignment
  • Good in areas where more space is required
    between the river and the objects to be protected
  • Excellent method where areas claimed by lateral
    stream migration must be reclaimed

176
Red Banks, MS. 3-92 LPSTP with tiebacks, some
flow since construction
Red Banks, MS. 6-93One year later, unrooted
willow stakes plus natural revegetation equals
stability.
177
CASE STUDYGrand River at Route A 100 miles
north of Kansas City, MO. Constructed June
2001False Banklines using LPSTP(medium-sized
river)
178
LPSTP CONFIGURED AS A FALSE BANKLINE ON A
LARGE RIVER, MINIMAL BACKFILLING BEHIND LPSTP
  • Grand River at Route A 100 miles north of
    Kansas City, MO. rural, sand-gravel, slope lt1,
    pool-riffle-pool, meandering. This is a Kansas
    City District Corps of Engineers Section 14
    project, emergency bank stabilization to protect
    existing public works (highway and bridge). I
    was involved in the conceptual design, HNTB,
    Inc. developed Plans and Specs. Much thanks to
    John Blancett, engineer with HNTB for project
    monitoring, great pix, Plans and Specs.

Mini case study 1 of 13
179
LPSTP Cross-sections. Top bank el. 806 Q-2
flow el. 803 LPSTP crest 793 Designed to be
overtopped 13 days/yr. Core section of LPSTP
was built of a less expensive stone, while
quarry run stone was used for all exposed surfaces
Pix by John Blancett, HNTB, Inc.
Mini case study 2 of 13
180
Planform design drawing from HNTB. The bend US
of the project bend had migrated 1,100 ft in 59
years, but was averaging 50 ft per year from
1993-1999 (after disturbance from 1993 flood).
Bridge
LPSTP
Key
Existing bridge protection
Tie-backs keys
Pix by John Blancett, HNTB, Inc.
Mini case study 3 of 13
181
LPSTP on a large river, looking US. The bend US
of this bend had migrated 1,100 ft in 59 years.
Pix by John Blancett, HNTB, Inc.
Mini case study 4 of 13
182
MAIN PROJECT GOALS
  • LPSTP was moved away from existing bank (false
    backline) so as to improve flow through the
    bridge opening and to reduce erosive pressure on
    opposite bank downstream of bridge.

Mini case study 5 of 13
183
Looking DS, Grand River, very poor flow alignment
into Route A bridge opening, pre-project
conditions
Mini case study 6 of 13
Pix by Derrick
184
Great shot Pix by John Blancett, HNTB, Inc., note
old bank angle approach new LPSTP flow approach
angle into Route A highway bridge
NEW APPROACH ANGLE
Old approach angle
Mini case study 7 of 13
185
Looking US, flow at crest of LPSTP, Grand River
at Route A, South of Albany, MO. Q-2 flow
would be 3 ft below top bank. Q-2 flow is 10 ft
higher than the crest of the LPSTP.
Pix by John Blancett, HNTB, Inc.
Mini case study 8 of 13
186
June 2001 - Looking US at just completed project.
Grand River _at_ Rt. A, MO
Pix by John Blancett, HNTB, Inc.
Mini case study 9 of 13
187
Looking US. Note deposition and veg within first
year after completion. Grand River _at_ Rt. A, MO
Pix by John Blancett, HNTB, Inc.
Mini case study 10 of 13
188
Sept 2002 1 year after completion. Looking
US. Nature is softening the project. Grand
River _at_ Rt. A, MO
Pix by John Blancett, HNTB, Inc.
Mini case study 11 of 13
189
May 3, 2006 5 years after completion. Looking
US. Native vegetation improves project
aesthetics/functions, Grand River _at_ Rt. A, MO
Pix by John Blancett, HNTB, Inc.
Mini case study 12 of 13
190
Oct 4, 2007 - After 6 years robust native
vegetation results in a fully functional project,
Grand River _at_ Rt. A, MO
Pix by John Blancett, HNTB, Inc.
Mini case study 13 of 13
191
Longitudinal Fill Stone Toe Protection
LFSTP (also called a Weighted Toe or a
Reinforced Revetment)
  • Description -Longitudinal Fill Stone Toe
    Protection (LFSTP) is similar to LPSTP, except
    that instead of coming to a peak, the crest has a
    specified width. Therefore, LFSTP has a
    trapezoidal cross-section as compared to the
    triangular cross-section of LPSTP.
  • Advantages - Same as LPSTP. In addition, in
    areas of deep scour LFSTP provides sufficient
    rock to self-adjust (launch) into the scour hole
    while still maintaining its original crest
    height.
  • Design considerations - The maximum scour depth
    should be calculated. The volume of stone
    required to launch into and armor the scour hole
    (with an appropriate margin-of-safety
    incorporated into the design) should be
    calculated. Based on these calculations, the
    crest width (volume of launchable stone needed
    from the LFSTP) can then be back-calculated.

192
Typical colluvium alluvium deposition (note
swale, good for wetland plants but can drown
young planted willow)
LFSTP is similar to LPSTP but it has a crest
width!
Longitudinal Fill Stone Toe Protection (LFSTP)
193
Longitudinal Fill Stone Toe Protection (LFSTP)
Original height of protection still maintained
after stone has launched into deep scour hole
194
CASE STUDY- Missouri River _at_ Lewis Clark
Regional Water System, Vermilion, SD.
Constructed Nov. 2007-Apr. 2008Longitudinal
Fill Stone Toe Protection LFSTP with
integrated Locked Logs
195
Aerial shot fall 2007. Looking US _at_ completed
mile-long L C project.
196
CONCEPTUALLY
  • Start with a standard bank protection plan that
    is well understood, well designed, time tested
    (low degree of risk)
  • Add to this the hydraulically rough
    environmentally desirable Extreme Locked Logs
    (113 logs spaced 50 ft apart) plus 49,000
    unrooted willow pole plantings within through
    the riprap, 59,300 rooted stock plants for the
    mid upper bank areas. Then cover (choke) all
    exposed stone with 1 ft of soil seed !!

197
LONGITUDINAL FILL STONE TOE PROTECTION
LFSTPSelf-adjusting self-filtering stone.
Minimum 10 ft wide by minimum 3 ft thick.
Contractor placed 22,986 tons of stone for entire
launchable toe. (Amounts in actual
construction have varied from 3.2 to 4.6 tons/ft.
in concave straight sections, to 6.3 to 8.4
tons/per ft. at convex areas (juts).
198
Stabilization / habitat cross-section from HDR,
Inc.
CONSTRUCTION -MISSOURI RIVER _at_ L C
199
Looking US _at_ the 10 ft wide Longitudinal Fill
Stone Toe Protection. The bank will be graded to
3 on 1 with riprap integrated veg
CONSTRUCTION-MISSOURI RIVER _at_ L C-TERRY
STOLTENOW-11/8/07
200
Looking US. Smoothing choke soil with the
Bobcat. Minimum of 6 inches of soil choke, but
contractor applied 12 inches almost everywhere.
Some settling will occur.
CONSTRUCTION-MISSOURI RIVER _at_ L C-TERRY
STOLTENOW-12/5/07
201
INSTALLATION OF THE EXTREME LOCKED LOGS
202
BANK CROSS-SECTION FROM HDR., INC
Self-Adjusting LFSTP
Extreme Locked Log
Looking US at Station 1100
203
LONGITUDINAL FILL STONE TOE PROTECTION WITH
INTEGRATED EXTREME LOCKED LOGS (Fuzzy
Locked Log shown next)
204
Looking US. A cedar Fuzzy Extreme Locked Log
CONSTRUCTION-MISSOURI RIVER _at_ L C-DERRICK-NOV
15, 2007
205
Looking US. Scraping branches off of the lower
15 ft of the Fuzzy Extreme Locked Log so stone to
trunk contact is made, then the Locked Log is
truly locked in place.
CONSTRUCTION-MISSOURI RIVER _at_ L C-DERRICK-NOV
15, 2007
206
Looking US. Note calm water between Locked Logs.
LFSTP 10 ft wide
CONSTRUCTION-MISSOURI RIVER _at_ L C-DERRICK-NOV
15, 2007
207
Looking US. Turbulence off ends of ExLL with
flat water DS. Uneven shore mimics nature.
Note soil-choked stone.
CONSTRUCTION-MISSOURI RIVER _at_ L C-DERRICK-NOV
15, 2007
208
Looking US _at_ self-adjusting toe stone Extreme
Locked Logs, note natural bank with wood upstream.
CONSTRUCTION-MISSOURI RIVER _at_ L C-DERRICK-NOV
15, 2007
209
Looking DS. Irregular bankline mimics natural
shore
CONSTRUCTION-MISSOURI RIVER _at_ L C-DERRICK-NOV
15, 2007
210
EXTREME LOCKED LOGS WITH ICE
211
Ice surrounding ExLL fends off moving ice floes.
CONSTRUCTION-MISSOURI RIVER _at_ L C-DERRICK-DEC
11, 2007
212
Looking DS at ice buildup US of natural jam.
CONSTRUCTION-MISSOURI RIVER _at_ L C-DERRICK-DEC
11, 2007
213
Looking US. Close-up of ice surrounding ExLL.
CONSTRUCTION-MISSOURI RIVER _at_ L C-DERRICK-DEC
11, 2007
214
PLANT PLANTS WITH VERY LARGE YELLOW
MACHINES
215
BANK CROSS-SECTION FROM HDR., INC
Riprap blanket on 3 to 1 slope, 3 ft thick, with
49,000 integrated willow pole plantings in 4 rows
Self-Adjusting LFSTP
Locked Log
Looking US at Station 1100
216
Terry Stoltenow, construction inspector with HDR,
Inc. with 6-7 ft long bundled willows.
CONSTRUCTION-MISSOURI RIVER _at_ L C-DERRICK-DEC
11, 2007
217
Pull bucket back 8, lean willow poles against
stone.
CONSTRUCTION-MISSOURI RIVER _at_ L C-DERRICK-Dec
13, 2007
218
Looking US. All 4 rows of willows
CONSTRUCTION-MISSOURI RIVER _at_ L C-DERRICK-Dec
12, 2007
219
Looking US at willows stone.
CONSTRUCTION-MISSOURI RIVER _at_ L C-DERRICK-DEC
11, 2007
220
All 4 rows of willow integrated into riprap
soil choked
CONSTRUCTION-MISSOURI RIVER _at_ L C-DERRICK-Dec
12, 2007
221
Looking US. Nature is curvaceous, us too !!
Edge of stone toe
CONSTRUCTION-MISSOURI RIVER _at_ L C-DERRICK-Feb
25, 2008
222
PLANT PLANTS WITH A MUCH SMALLER
MACHINE 59,300 bare root plants even amount of
cottonwood red osier dogwood were installed on
a 4 to 1 slope from elevation 1130 up to top of
bank during March 26 - May 4, 2008 .
223
BANK CROSS-SECTION FROM HDR., INC
Bank sloped at 4 to 1 with 59,300 rooted-stock
plants in anywhere from 6 to 16 rows (dependant
on bank height), but we would also like to put
some at the toe within the willows
224
Ancient two seat single row planter was used to
plant 8,000 rooted stock plants per day, finished
4/28/2008, 3 months ahead of schedule.
CONSTRUCTION-MISSOURI RIVER_at_L C-TERRY
STOLTENOW-4/3/08
225
3 MONTHS AFTER PROJECT COMPLETIONPhotos by
Derrick August 1, 2008
226
3 months after completion, looking DS _at_ L C
project highway bridge.
3 MONTHS LATER- MISSOURI R._at_L C-PIX BY DERRICK
8-1-2008
227
From upper section of project looking DS toward
bridge. Willow, cottonwood dogwood growth 3
months after planting is robust. Some erosion of
soil at waters edge slight launching of stone.
3 MONTHS LATER- MISSOURI R._at_L C-PIX BY DERRICK
8-1-2008
228
Looking DS _at_ some exposed stone some launching,
nothing excessive.
3 MONTHS LATER- MISSOURI R._at_L C-PIX BY DERRICK
8-1-2008
229
Looking US. Wave ice action have removed some
riverside soil choke.
3 MONTHS LATER- MISSOURI R._at_L C-PIX BY DERRICK
8-1-2008
230
Looking US _at_ uneven bankline, plantings Extreme
Locked Logs. A little of the Longitudinal Fill
Stone Toe exposed at edge
3 MONTHS LATER- MISSOURI R._at_L C-PIX BY DERRICK
8-1-2008
231
Looking US. Soil veg good 3 months after
installation. LFSTP looks good
3 MONTHS LATER- MISSOURI R._at_L C-PIX BY DERRICK
8-1-2008
232
Looking US _at_ LFSTP Locked Logs (some are
underwater)
3 MONTHS LATER- MISSOURI R._at_L C-PIX BY DERRICK
8-1-2008
233
Close-up of willow pole plantings 3 months after
installation.
3 MONTHS LATER- MISSOURI R._at_L C-PIX BY DERRICK
8-1-2008
234
Mid to upper bank plantings. Cottonwoods 22 to
48 tall, Red Osier Dogwoods 16 to 31 tall. 3
ft between rows, from 12 to 18 spacing between
plants in a row.
3 MONTHS LATER- MISSOURI R._at_L C-PIX BY DERRICK
8-1-2008
235
  • Stream Project Functions
  • Fully functioning both hydraulically
    environmentally. Multiple protection
    redundancy. Extreme Locked Logs move scour
    thalweg away from attacked bank should
    recruit SWD LWD. Self-adjusting toe stone
    provides protection against scour. Riprap
    revetment provides direct armor protection.
    Vegetation roughness reduces near-bank flow
    velocities invites deposition. Plant roots
    strengthen bank bind soil.

236
CONSTRUCTION-MISSOURI RIVER_at_L C-TERRY
STOLTENOW-11/29/07
237
REGARDING QUESTIONS, I AM ALL EARS !!!
Each ear is 10 inches long, front legs are 5
inches long
Cleophus at 8 weeks
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