FLOOD10351

• County: Statewide
• Community: Statewide
• Title: Statewide River Rehabilitation & Flood Plain Management Needs Inventory
• Date: 12/1/1998
• Prepared For: State of Colorado Department of Natural Resources
• Prepared By: McLaughlin Water Engineers
• Floodplain - Doc Type: Floodplain Report/Masterplan

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CIWlNEL
WIDTH

FLOW HABIT

CHANNEL
BOUNDARIES

BED MATERIAL

VAlLEY;
OR OTHER
SETTING

FLOOD PLAIN

DEGREE OF
S I NooS ITY

DEGREE OF .
BRAIDING

DEGREE OF
ANABRANCHING

VARIAB ILITY
OF WIDTH
AND
DEVELOPMENT
OF BARS

APPARENT
INCISION

CUT BANKS

BANK
MATERIAL

TREE COVER
ON BANKS

Figure VII-2
Stream Properties for Stream Classification

Small Medium
(<100 ft or 30 III wide) (100-500 ft or 30-150 m)

Wide
(>500 ft or 1 SO ,11)

Ephemera 1

(I ntenni ttent)

Perennial but flashy

Perennh 1

g~
' .' "', ""'~:'~"""',".
.' :..: ," :'": ::'. _4..... ..'. .

~.. ...~..
-- :~.' ...
I, .' ,,' ..',::".:-
~
Semi-all uv1a 1

~
-. , - .' .~, ., .
....... -
III' .... I:
Non-alluvial

Alluvial
Sl1 t-clay

Sl1t

Sand

Gravel

Cobb)e or boulder

~
- ,':."

c...~...u ,"'~ ~.,\\,
~...... '.... , ,.,""~ :'. so~_
. . . ./ ~""-';' ::::;'''2'';:;':1
'- ~ ~~. ::~~~;fi:~7.~~1
Moderate relief High relief No valley;
(100-1000 ft or 30-300 m) (>1000 ft or 300 m) alluvial fan

Low relief valley
(<100 ft or,30 m deep)

~
. ~.. . ," . . " -.'
. . .....:. I..;;...

~..~
',"7'-- ... :.:.... ','~": ,...
. .n... ":::'.::~ ~~,I:."',.~:"""

Narrow
(Z-10x channel width)

F'....~
~;; : :';: :.><~'~ . .':;,'';.~..r~
Wide
(>lOx channel width)

little or none
(<2x channel width)

-- ~ ;::

~~

=--

~

Stra~ght
(Sinuosity 1-1.05)

Sinuous
(1.06-1.25) ,

Meandering
(1.26-2.0)

Highly meander1ng
(>2)

Not braided
(<5 percent)

~
Locally braided
(5-35 percent)

--~~~ ,
~
Generally braided
(>35 percent)

~

Generally anabranched I
(>35 percent)

Not anabranched
(<5 percent)

~

Locally anabranched
(5-35 percent)

SlrJ

~

r~

Equ1width
A

Narrow point bars

Wider at bends

,~~

Wide pOint bars

Random vari ation

~

Irregular pOint and lateral bars

~~-~
:::::t: ~~-=:
Not inched

E~
... =, ~~~,.

Probabiy lnClsed

Rare

Local

Genera 1

Coherent
Resistant bedrock
Non-resistant bedrock
Alluvium

Non-coherent
S i It; sand
gravel;
cobble; boulder

<SO percent of banldine

1

50-90 percent

>90 percent

(Federal Highway Administration, .NIn #13010, 1990)

Section VII - 4