FLOOD03332

• County: Statewide
• Community: State of Colorado
• Basin: Statewide
• Title: Bank Erosion/Self-Help Brochure
• Date: 4/19/1984
• Prepared For: State of Colorado
• Floodplain - Doc Type: Educational/Technical/Reference Information

ROCK RIPRAP PROTECTION -
BANKLINE AND WINDROW REVETMENTS

Bankllne Revetment - This protection method consists of protecting the lower underwater
slope with stone fll I to prevent undercutting of the banks. This method should be used
along shorelines wher.e the lower bank material Is very erosive, such as a sandy material.
Stone fll led tiebacks should be placed Intermittently to provide erosion protection to the
upper bank and prevent river flows trom eroding In behind the lower slope protection.

-----{

J
tj,

,

~);:g;)- _ 8ANK~'Nf

r,;lI'IIIIII'"""''''III''''''
)" '11111...

<'I'~

---~~----
)1-'1'-
"1IIH",llld~liil"1 ,
"~C~.'''''''':i'':.';''
1,"", i,,~,.._

c-

~~~-

/
./

Flow
~~
.....-

--------

Stone filled Tlebac'
€'~200' spacing.

Normal
/Vater Surl-ace

TYPICAL SECTION

Windrow Revetment - This erosion control method consists of placing stone along the top of
the existing bankllne at a predetermined location beyond which additional erosion would
not be permitted. Rlprap has also been used effectively with a ''Trench-Fill Technique.1I
Along with bank grading, a trench Is excavated at the base and filled with rlprap. Both
the surface and trench-fll I methods consist of placing (or burying) a sufficIent amount of
stone fill In a windrow behind the top of the bankllne, then permitting the area between
the natural riverbank and the windrow to erode through natural processes, untl I it reaches
and undercuts the supply of stone. As the stone Is undercut it falls Into the eroding
area and provides protection against further undercutting. The resulting bankllne would
remain In a near natural state with an Jrregular appearance. Portions of the stone fll I
windrow that are not eroded into the rIver by the natural process would be available for
relocation to severely eroding areas at a later date. The windrow revetment is
recommended for use in light forested areas and along stretches of Irregular bankllne.

13