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TRADITIONAL WINDROW &TRENCH-FILL REVETMENTS,
& A NEW INVENTION, VEGETATED TRENCH-FILL
REVETMENT{All 3 are classified as “Setback
Revetments”}
THESE ARE ALL SELF-ADJUSTING, SELF-HEALING
BANK STABILIZATION METHODS (NOT
FOUNDATION DEPENDENT) THAT ARE USUALLY BUILT
OUTSIDE THE ACTIVE STREAM CHANNEL
1. Typically easy to construct & inspect2. Bank erosion must occur for the windrow or trenchfill stone to
launch into the scoured area3. In-stream construction is avoided4. Self-adjusting, self-filtering stone is required5. Maximum scour depth must be calculated to to determine volume
of stone required. Rule of thumb is 1 ton of stone per foot will stabilize 3 ft of scour.
6. Works best in easily eroded, non-cohesive soils exhibiting a uniform erosion rate throughout the entire bend
7. Can be quickly & easily constructed, comparatively inexpensive, easy to inspect. Since all work is outside the channel & above OHW, some permits might not be required!
WINDROW REVETMENTS
A continuous volume of stone placed on an engineered alignment landward
of an actively eroding riverbank or streambank.
WINDROW REVETMENT, KANSAS RIVER, EUDORA BEND, KS. Approx. half of the stone has launched, remainder is still on top bank. Bank stable & vegged.
TRENCH-FILL REVETMENTCalculated volume of stone placed in a trench on an
engineered alignment landward of an eroding bank. As erosion undermines the trench, stone is designed to self-adjust (launch) into the scoured area forming a stable, adjustable toe (or toe & mid-bank protection, depending on bank height & depth of trench). In some projects the upper bank is graded & either vegetated or riprapped.
Trenchfill Revetment
Initial ChannelCross-Section
ExcavatedTrench
Disposal
WellGradedstone in trench
Active Eroding
Bank
MigratingChannel
Upper bank
riprap
From Freddie Pinkard COE, Vicksburg District, modified by DLD
Trenchfill Revetment
Initial ChannelCross-section
Launched stone
stabilized eroded
sections of bank (toe & mid bank)
Final ChannelCross-section
ErodingBank
Upper bank
riprap
From Freddie Pinkard COE, Vicksburg District, modified by DLD
TRENCHFILL REVETMENT, RED RIVER, LA. Designed to provide the correct alignment &
bend radii needed for navigation.
Red River, LA.-Trenchfill with upper bank paving. Foreshore almost completely eroded back to the trenchfill stone & weighted toe
TRENCHFILL REVETMENT-Stone is on the wrong side of the trench (away from river). When erosion undermines the trench as much stone as
possible needs to be launched immediately, not a few stones at a time!
Lan
d
Sid
eV
EG
ETA
TED
TR
EN
CH
-FIL
L
REV
ETM
EN
TS
-STEP
S IN
C
ON
STR
UC
TIO
N -
CO
MP
LETE
DONE
Vegetation on
backslope protected from river
forces allowing for great growth
RIV
ER
SID
E
THE BACKSTORY • Since the pipeline protection project is
totally off of the pipeline right-of-way, the use of several different shrub & tree bioengineering techniques can be used in conjunction with a continuous low-elevation stone toe protection & a set of redirective Bendway Weirs.
This PowerPoint presentation was developed & built by Dave Derrick.
Any questions or comments, call my personal cell @ 601-218-7717, or email @ d_derrick@r2d-eng.com
Enjoy the information!!
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