Detailed Information on In-Stream Restoration Activities ...Detailed Information on In-Stream...

Stratus Consulting SC11902 78

Upper Arkansas River Watershed Restoration Plan and Environmental Assessment

Appendix A

Detailed Information on In-Stream Restoration Activities(Th is information was developed by the Colorado Division of Wildlife.)

Habitat restoration actions, in tandem with further remediation eff orts, will signifi cantly contribute to restoring the brown trout population in metals-impacted stream reaches of the upper Arkansas River below California Gulch. Historical placer mining within the river and grazing in the riparian areas of the river have reduced the amount of quality habitat for the brown trout fi shery (Industrial Economics, 2006). Much of the 11-mile reach is over-width and aggraded, and presents as a continuous run or riffl e with little deep pool or undercut bank habitat for over-wintering refugia. In addition, the banks are highly erodible due to lack of strong establishment of riparian shrubs such as native high-elevation willow species. Mine tailings and spoils are largely responsible for the poor vegetative growth, as well as a history of grazing and railroad activity in the area.

Physical habitat improvements within the 11-mile reach (including habitat and geomorphology improvements, bank stabilization, and riparian improvements) are expected to improve the fi shery (density, biomass, spawning, and/or the number of large adult fi sh) up to 40% higher than current conditions. In-stream habitat restoration treatments are generally designed to perform one of the following functions, all of which directly or indirectly improve trout habitat: (1) improve natural river processes and connection between the river and the fl oodplain and riparian zone; (2) stabilize banks in a way which also creates winter habitat and cover for trout; and (3) enhance mid-stream habitats for trout and their prey base (forage fi sh or invertebrates). Photographs of in-stream restoration activities are included in Section A.3, bank erosion treatments in Section A.4, and aquatic habitat treatments in Section A.5.

Potential treatments for the entire 11-mile reach (Figure A.1) were identifi ed and evaluated for the Preliminary Estimate of Damages (Industrial Economics, 2006). Table A.1 describes the general nature of the habitat restoration treatments that serve these functions and that will be considered for the reaches in the 11-mile segment. Stream reaches will be prioritized to develop an in-stream restoration timeline based on the (1) status of the brown trout population, (2) level of current and future contamination, (3) ease of access for heavy equipment, (4) public access after restoration, and (5) presence/absence of confounding factors such as water rights, ditches, agricultural practices, etc. With this prioritization scheme, Reach 3 between Highway 24 and Kobe was ranked as Phase I. EPA has conducted recent work in this reach and thus there are access roads that will facilitate in-stream restoration activities. In addition, the brown trout populations in this reach have not recovered to reference levels, and since metals contamination is lower in this reach compared to directly below California Gulch, we hypothesize that habitat is the limiting factor. Phase II of the project will be on the Moyer easement and Reach 2, which also shows severely degraded habitat and will have public access. Phase III includes private property from California Gulch to the confl uence of the Lake Fork in Reach 1. Th ere are issues in Reach 1 that must be addressed, including the maintenance of ditch access and agricultural practices, and protection of grazing land and physical structures. Th ese issues may be best addressed with assistance from the National Resource Conservation Service. Work with private landowners was described in Section 3.3.1. Phase IV will include any point in Reach 4 where access and permission is granted.



Appendix A

Detailed Information on In-Stream Restoration ActivitiesProposed treatment regimes for in-stream habitat restorationTreatment regimes were proposed for the 11-mile reach of the upper Arkansas River based on initial inventory and survey techniques (Table A.1). Th ese techniques include qualitative assessments of bank stability and riparian vegetation, counts of riffl e to pool ratios, width to depth ratio measurements, aerial imagery at high and/or low fl ows, investigation of stream fl ow data from gauges, and determination of access logistics and private versus public property issues. Treatments for each reach are described in further detail below. Th ese treatments will be further evaluated and adjusted or deleted when engineering models are applied to develop the fi nal treatment plans for each reach. Nothing is currently proposed for the reference stream reach above California Gulch (Reach 0).

A.1 Engineering and DesignTo assist with evaluating the size of material (boulders, cobbles, etc.) to use in various habitat treatments, a two-dimensional computer model will be developed. Th e United States Army Corps of Engineers’ HEC-RAS computer program will be used to model each reach. Th is program is one of the industry standards for evaluating rivers in their current state as well as how planned improvements will aff ect the system. HEC-RAS utilizes river cross-section geometry, length of channel between cross-sections, channel roughness (amount of vegetation in the channel and overfl ow banks, size and shape of rock in the channel, etc.), and fl ow to determine water surface elevations, width of the water, and water velocity (impacts bank and channel bottom stability). Th e program will also help predict the ability of the river to transport sediment though the reach. Th is is important to design the river so there is neither agradation (deposit) nor degradation (erosion) at the structures.

Th e HEC-RAS computer model will evaluate river reaches as a system but is limited in its capability to predict how individual treatments/structures will aff ect the river at a particular location. To help evaluate the potential impacts that a particular treatment may have on the river in critical locations, it may be prudent to develop a three-dimensional model. Th ere are several good three-dimensional hydraulic computer programs currently in use, such as the USGS MD-SWMM program.

A.2 Project Management and ConstructionTh e preferred alternative of in-stream habitat restoration will require detailed engineering for each designated stream reach and associated construction and heavy equipment operations along the banks and within the streambed. While engineering plans will be adhered to as much as possible, there may be a need or opportunity for design-build activities beyond the engineering plans. Access roads previously developed by EPA for reclamation and restoration activities will be used, although additional access points may be required. Project management will require both knowledge of heavy equipment operations, placement of in-stream restoration treatment types, and fi sh behavior and ecology.



Appendix A

Detailed Information on In-Stream Restoration ActivitiesTA

BLE

A.1

. PRO

POSE

D R

ESTO

RATI

ON

TRE

ATM

ENTS

FO

R TH

E 11

-MIL

E RE

ACH

OF

THE

UPP

ER A

RKA

NSA

S RI

VER

A. D

escr

iptio

ns o

f tre

atm

ents

use

d to

impr

ove

natu

ral r

iver

pro

cess

Rive

r cha

nnel

tre

atm

ents

Rest

orat

ion

treat

men

t des

crip

tions

Redu

ce

Chan

nel W

idth

Exca

vate

d ch

anne

l sub

stra

te m

ater

ial,

impo

rted

grav

el, a

nd c

obbl

e or

ripa

rian

vege

tatio

n so

d bl

ocks

can

be

used

to re

duce

rive

r ch

anne

l wid

th.

Pool

Exc

avat

ion

Pool

hab

itats

sho

uld

be e

xcav

ated

at a

spa

cing

of a

bout

5−7

cha

nnel

wid

ths

alon

g ei

ther

out

side

rive

r cur

ves

or in

stra

ight

cha

nnel

re

ache

s. E

xcav

ated

sub

stra

te m

ater

ials

can

be

used

to c

reat

e po

int b

ars

and

redu

ce c

hann

el w

idth

.

Elev

ate

Riffl

e Su

bstra

teRi

ffl e

subs

trate

s ca

n be

ele

vate

d us

ing

grav

el o

r cob

ble

so it

will

not

be

trans

porte

d du

ring

high

-stre

am fl

ow e

vent

s. T

his

treat

men

t ca

n be

use

d to

incr

ease

cha

nnel

sub

stra

te e

leva

tion

in a

hig

h-fl o

w b

raid

ed c

hann

el re

ach.

Dur

ing

low

-riv

er d

isch

arge

this

trea

tmen

t co

nfi n

es th

e riv

er fl

ow in

to a

sin

gle

low

-fl ow

cha

nnel

. Dur

ing

high

fl ow

s th

e el

evat

ed ri

ffl e ch

anne

l bec

omes

an

over

-fl ow

cha

nnel

an

d re

duce

s th

e er

osio

n po

tent

ial a

long

rive

rban

ks in

the

low

-fl ow

cha

nnel

.An

ele

vate

d rif

fl e p

lace

d in

a lo

w-g

radi

ent r

iver

cha

nnel

cre

ates

add

ition

al c

hann

el ro

ughn

ess,

incr

ease

s tro

ut h

abita

t div

ersi

ty, a

nd

prov

ides

exc

elle

nt ju

veni

le tr

out h

abita

t.

Ripa

rian

Benc

h A

benc

h is

con

struct

ed u

sing

rive

r cha

nnel

sub

stra

te, r

iver

bank

mat

eria

ls, o

r im

porte

d so

il m

ater

ials

. The

top

elev

atio

n of

the

cons

truct

ed b

ench

sho

uld

be s

light

ly b

elow

ban

kful

l ele

vatio

n. B

lock

s of

ripa

rian

vege

tatio

n so

d sc

oope

d up

in a

buc

ket o

f an

exca

vato

r or f

ront

-end

load

er a

re p

lace

d on

top

of th

e co

nstru

cted

ben

ch. B

ucke

ts a

re ri

nsed

bef

ore

digg

ing

up th

e so

d. A

fter l

oadi

ng

the

sod

bloc

k, it

is s

oake

d in

wat

er b

efor

e be

ing

plac

ed o

n th

e pr

epar

ed b

ench

. The

soa

king

hel

ps th

e ve

geta

tion

bloc

k sl

ide

from

th

e bu

cket

. The

top

elev

atio

n of

the

plac

ed ri

paria

n so

d sh

ould

be

slig

htly

abo

ve b

ankf

ull e

leva

tion.

Dep

endi

ng u

pon

the

mat

eria

l size

us

ed to

con

struct

the

benc

h an

d th

e riv

er g

radi

ent,

it m

ay b

e ne

cess

ary

to li

ne th

e fro

nt o

f the

ripa

rian

benc

h w

ith a

ppro

pria

tely

size

d co

bble

to le

ssen

rive

rban

k er

osio

n.

Incr

ease

Ov

erhe

ad

Trou

t Cov

er

Unde

r Woo

dy

Vege

tatio

n

Site

s be

st a

dapt

ed fo

r thi

s tre

atm

ent h

ave

woo

dy v

eget

atio

n cr

eatin

g ov

erhe

ad c

over

in ri

ver r

each

es loca

ted

alon

g ou

tsid

e riv

er

curv

es w

here

trou

t hab

itat i

s lim

ited

by s

hallo

w w

ater

. Add

ition

al tr

out h

abita

t is cr

eate

d us

ing

an e

xcav

ator

by

exte

ndin

g th

e bo

om

and ca

refu

lly re

mov

ing

river

cha

nnel

sub

stra

te m

ater

ial u

nder

the

woo

dy v

eget

atio

n. T

he incr

ease

d w

ater

dep

th c

reat

es m

ore

usea

ble

over

head

cov

er fo

r tro

ut.

Ripa

rian

Vege

tatio

nM

ovin

g w

illow

clu

mps

dur

ing

the

dorm

ant s

easo

n m

axim

izes

succ

ess

of s

urvi

val.

Surv

ival

of b

are

root

will

ow s

tock

and

dor

man

t stu

b pl

antin

gs, p

lant

ed d

eep

enou

gh to

rem

ain

in p

erm

anen

t soi

l moi

stur

e, s

houl

d exc e

ed 8

0%. S

eedi

ng a

ppro

pria

te ri

paria

n gr

ass

spec

ies

alon

g st

ream

ban

ks d

istu

rbed

dur

ing

rest

orat

ion

incr

ease

s th

e reco

very

of r

ipar

ian

vege

tatio

n.



Appendix A

Detailed Information on In-Stream Restoration Activities B

. Des

crip

tions

of w

oody

mat

eria

ls tr

eatm

ents

use

d to

redu

ce ri

verb

ank

eros

ion

Bank

ero

sion

tre

atm

ents

Rest

orat

ion

treat

men

t des

crip

tions

Log

Spur

Logs

for t

his

treat

men

t sho

uld

exce

ed 1

ft in

dia

met

er. I

n loca

tions

whe

re s

tream

ban

ks a

re c

ompo

sed

of a

lluvi

al m

ater

ial,

a tre

nch

shou

ld b

e du

g in

to th

e to

p of

the

river

bank

. The

ang

le o

f the

tren

ch faci

ng u

pstre

am s

houl

d be

15−

25 d

egre

es fr

om th

e ta

ngen

t lin

e w

here

the

log

inte

rcep

ts th

e riv

erba

nk a

nd h

ave

a do

wnw

ard

slop

e of

2−7

deg

rees

. The

top

elev

atio

n of

the

log

whe

re it

mee

ts th

e st

ream

ban

k sh

ould

be

at o

r slig

htly

abo

ve b

ankf

ull e

leva

tion.

Abo

ut o

ne-h

alf t

he le

ngth

of t

he lo

g sh

ould

be

plac

ed in

to th

e riv

erba

nk.

The

upst

ream

end

of t

he lo

g sh

ould

be

belo

w th

e w

ater

sur

face

at l

ow fl

ow a

nd b

urie

d in

to th

e ch

anne

l sub

stra

te. F

or a

dditi

onal

anch

orin

g an

d tro

ut h

abita

t, a

boul

der c

an b

e pl

aced

on

the

upst

ream

end

of t

he lo

g th

at is

bur

ied

in th

e riv

er s

ubst

rate

. A b

ould

er

plac

ed n

ext t

o th

e riv

erba

nk o

n th

e do

wns

tream

sid

e of

the

log

prov

ides

an

addi

tiona

l anc

hor.

Rath

er th

an e

xcav

atin

g a

trenc

h, if

st

ream

ban

ks c

onta

in m

oist

cla

y or

silt

, the

log

may

be

push

ed o

r pul

led

into

the

river

bank

.

Log

Vane

This

trea

tmen

t is

inst

alle

d th

e sa

me

as a

log

spur

. Log

leng

th s

houl

d exce

ed 2

0 ft

and

the

log

angl

e sh

ould

be

15−2

0 de

gree

s fro

m th

e ta

ngen

t lin

e w

here

the

vane

inte

rcep

ts th

e riv

erba

nk a

nd h

ave

a do

wnw

ard

slop

e of

2−7

deg

rees

. Fab

ric m

ater

ial s

houl

d be

place

d be

twee

n th

e riv

erba

nk a

nd th

e lo

g. T

he fa

bric

sho

uld

be a

ttach

ed a

t the

top

of th

e lo

g an

d co

vere

d w

ith e

xcav

ated

sub

stra

te m

ater

ial.

Unlik

e a

log

spur

that

pas

ses

wat

er u

nder

the

log,

the

fabr

ic m

ater

ial c

over

ed w

ith s

ubst

rate

mat

eria

ls fo

rces

wat

er to

pas

s ov

er th

e lo

g di

rect

ing

it to

war

d th

e ce

nter

of t

he ri

ver.

Rive

rban

k Ro

ot

Wad

A ro

ot w

ad fa

n sh

ould

exc

eed

3 ft

in d

iam

eter

hav

ing

at le

ast a

12

ft at

tach

ed tr

unk.

The

trun

k sh

ould

be

burie

d in

a tr

ench

or p

ushe

d in

to a

sof

t cla

y/si

lt ba

nk s

o th

e ro

ot fa

n is

ups

tream

at a

n an

gle

that

slig

htly

def

ects

sur

face

wat

er c

urre

nts

tow

ard

the ce

nter

of t

he

stre

am. T

he to

p of

the

root

wad

sho

uld

be a

bout

1 ft

abo

ve b

ankf

ull d

isch

arge

and

place

d fl u

sh a

gain

st th

e st

ream

ban

k.

Horiz

onta

l Pa

ralle

l Log

/Ro

ot W

ad

Horiz

onta

l log

s ar

e be

st s

uite

d fo

r riffl

e a

nd ru

n ha

bita

ts. T

he lo

g sh

ould

be

at le

ast 2

ft in

dia

met

er a

nd e

xcee

d ab

out 1

2 ft

in le

ngth

. De

pend

ing

upon

rive

rban

k st

abili

ty, i

t may

be

nece

ssar

y to

place

an

appr

opria

te fa

bric

mat

eria

l ext

endi

ng fr

om th

e riv

er s

ubst

rate

up

to a

bout

ban

kful

l ele

vatio

n. T

he to

p of

the

horiz

onta

l log

is p

lace

d ag

ains

t the

fabr

ic a

t abo

ut b

ankf

ull e

leva

tion

and

para

llel t

o th

e st

ream

fl ow

. The

spa

ce b

etw

een

the

botto

m o

f the

log

and

the

river

sub

stra

te c

reat

es o

verh

ead

trout

cov

er. T

he s

uppo

rt sy

stem

fo

r the

hor

izont

al lo

g is

site

spe

cifi c

. If t

he lo

g ha

s an

atta

ched

root

wad

this

sup

ports

one

end

of t

he lo

g. O

n th

e ot

her e

nd o

f the

lo

g, s

mal

l fl a

t bou

lder

s or

ano

ther

log

plac

ed p

erpe

ndic

ular

to th

e riv

er fl

ow a

nd s

ecur

ed in

to th

e riv

erba

nk s

uppo

rts th

e lo

g. It

is

impo

rtant

that

the

horiz

onta

l log

is s

uspe

nded

onl

y on

eac

h en

d. T

his

help

s m

aint

ain

wat

er v

eloc

ities

hig

h en

ough

to k

eep

river

-tra

nspo

rted

sedi

men

ts fr

om acc

umul

atin

g al

ong

the

unde

rsid

e of

the

horiz

onta

l log

and

redu

cing

are

as tr

out u

se a

s ov

erhe

ad c

over

. In

ove

r wid

th ri

ver c

hann

els

or w

here

the

log

does

not

fi t s

nug

agai

nst t

he b

ank,

a s

econ

d, u

sual

ly s

mal

ler d

iam

eter

, log

is p

lace

d be

hind

the

horiz

onta

l log

at a

slig

htly

low

er e

leva

tion.

The

are

a be

twee

n th

e ch

anne

l sub

stra

te a

t the

bas

e of

the

river

bank

, ove

r the

lo

wer

ele

vatio

n lo

g to

the

top

of th

e ho

rizon

tal l

og, i

s co

vere

d w

ith fa

bric

mat

eria

l and

bac

kfi ll

ed u

sing

soi

ls c

apab

le o

f sup

porti

ng

ripar

ian

vege

tatio

n. If

ava

ilabl

e, ri

paria

n gr

ass/

will

ow s

od is

place

d on

the

fi ll m

ater

ial o

ut to

the

front

edg

e of

the

horiz

onta

l log

. Thi

s re

sults

in a

nat

ural

app

earin

g st

ruct

ure

that

cre

ates

ove

rhea

d tro

ut c

over

und

er b

oth

logs

.



Appendix A

Detailed Information on In-Stream Restoration ActivitiesC.

Des

crip

tions

of b

ould

er tr

eatm

ents

use

d to

redu

ce ri

verb

ank

eros

ion

Bank

ero

sion

tre

atm

ents

Rest

orat

ion

treat

men

t des

crip

tions

Cros

s Va

neUs

ually

a c

ross

van

e is

place

d at

the

uppe

r end

of a

n exca

vate

d po

ol to

cre

ate

a di

vers

ity o

f tro

ut h

abita

ts a

nd d

irect

rive

r fl o

ws

tow

ard

the ce

nter

of t

he c

hann

el. T

his

struct

ure

help

s re

duce

rive

rban

k er

osio

n al

ong

the

outs

ide cu

rve.

The

fi rs

t few

bou

lder

s fo

rmin

g ea

ch s

ide

of th

e st

ruct

ure

upst

ream

are

place

d on

a 2

0o −30o a

ngle

from

the

river

bank

. The

rest

of t

he b

ould

ers

are

plac

ed

acro

ss th

e ch

anne

l res

embl

ing

an u

pstre

am fa

cing

arc

h ac

ross

the

river

. Em

bed

the

fi rst

bou

lder

into

the

river

bank

at a

bout

1 ft

ab

ove

bank

full

elev

atio

n. A

fabr

ic m

ater

ial p

lace

d be

hind

this

bou

lder

hel

ps re

duce

futu

re ri

verb

ank

eros

ion.

Thi

s fi r

st b

ould

er k

eys

the

struct

ure

and

direct

s th

e w

ater

cur

rent

aw

ay fr

om th

e er

odin

g riv

erba

nk. D

epen

ding

on

boul

der s

hape

s an

d th

e w

ay th

e w

ater

is

dire

cted

from

the

bank

, eac

h succ

eedi

ng b

ould

er is

place

d lo

wer

in th

e w

ater

col

umn

than

the

prev

ious

one

. The

low

est e

leva

tion

boul

der i

s loca

ted

near

mid

-cha

nnel

at a

bout

25%

of b

ankf

ull e

leva

tion.

The

hyd

raul

ic ju

mp,

the

diffe

renc

e in

wat

er s

urface

ele

vatio

n be

twee

n th

e up

stre

am a

nd d

owns

tream

sid

e of

a b

ould

er, i

s us

ually

no

mor

e th

an 1

2–15

inch

es. B

ould

er e

leva

tions

nea

r mid

-cha

nnel

ar

e th

en g

radu

ally

incr

ease

d un

til re

achi

ng th

e op

posi

te s

ide

of th

e riv

er. T

he fi

nal b

ould

er is

em

bedd

ed a

nd b

lend

ed in

to th

e to

p el

evat

ion

of th

e co

nstru

cted

poi

nt b

ar, w

hich

is u

sual

ly le

ss th

an b

ankf

ull d

isch

arge

. Ero

sion

is s

eldo

m a

n is

sue

on th

e po

int b

ar s

ide

of th

e riv

er c

hann

el b

ecau

se p

oint

bar

s ar

e us

ually

dep

ositi

onal

are

as.

Sing

le B

ould

er

Defl ect

orSi

ngle

bou

lder

defl

ect

ors

shou

ld h

ave

a so

mew

hat fl

at s

ide

and

be ta

ll en

ough

to e

xten

d fro

m a

sha

llow

poc

ket i

n th

e ch

anne

l su

bstra

te to

abo

ut 1

2−15

inch

es a

bove

ban

kful

l ele

vatio

n. T

his

treat

men

t is

best

sui

ted

for e

rodi

ng ri

verb

anks

stil

l con

tain

ing cl

umps

of

ripa

rian

vege

tatio

n an

d ha

ving

a b

ank

top

elev

atio

n ne

ar b

ankf

ull e

leva

tion.

Sin

gle

boul

der d

efl ect

ors ca

n be

use

d to

div

ert r

iver

fl o

ws

away

from

tall

erod

ing

river

bank

s bu

t doe

s no

t hel

p th

e riv

erba

nk h

ealin

g pr

oces

s if

void

of v

eget

atio

n.Du

ring

inst

alla

tion,

exca

vate

a d

epre

ssio

n to

fi t t

he s

hape

of t

he b

otto

m s

ide

of th

e bo

ulde

r and

rem

ove

river

bank

soi

l to

match

the

shap

e of

the

boul

der

side

to b

e em

bedd

ed in

to th

e er

odin

g riv

erba

nk. P

lace

an

appr

opria

te fa

bric

mat

eria

l int

o th

e de

pres

sion

and

alo

ng th

e riv

erba

nk

whe

re th

e bo

ulde

r will

be

plac

ed. T

he u

pstre

am e

nd o

f the

bou

lder

is e

mbe

dded

dee

per i

nto

the

river

bank

whi

le th

e do

wns

tream

end

ex

tend

s sl

ight

ly in

to th

e riv

er. T

he s

ingl

e bo

ulde

r defl

ect

or g

ently

defl

ect

s su

rface

wat

er c

urre

nts

tow

ard

the ce

nter

of t

he ri

ver.

The

boul

der d

efl ect

or re

duce

s riv

erba

nk e

rosi

on a

sho

rt di

stan

ce d

owns

tream

, dep

endi

ng o

n th

e de

fl ect

ion

angl

e an

d th

e cu

rvat

ure

of

the

river

bank

. Afte

r the

fi rs

t sin

gle

boul

der d

efec

tor h

as b

een

inst

alle

d, th

e loca

tion

for t

he s

econ

d is

obv

ious

by

obse

rvin

g th

e riv

er

surfa

ce fl

ows.

The

dis

tanc

e w

here

the

river

sur

face

cur

rent

retu

rns

to th

e riv

erba

nk b

ecom

es th

e si

te fo

r the

nex

t bou

lder

defl

ect

or.

This

trea

tmen

t wor

ks b

est w

here

rive

rban

k er

osio

n is

not

so

seve

re a

nd e

noug

h riv

erba

nk v

eget

atio

n re

mai

ns to

pro

tect

the

river

bank

be

twee

n bo

ulde

r defl

ect

ors.

If ri

verb

anks

are

sev

erel

y er

oded

, rev

eget

atio

n m

ay b

e ne

cess

ary

betw

een

boul

der d

efl ect

ors.

Hard

Poi

ntTh

is tr

eatm

ent m

imic

s a

stab

le ri

verb

ank

betw

een

the

low

rive

r fl o

w a

nd b

ankf

ull e

leva

tion.

It is

bes

t sui

ted

for a

riffl

e re

ach

on a

n ou

tsid

e cu

rve.

The

trea

tmen

t req

uire

s su

bstra

te m

ater

ial o

r im

porte

d m

ater

ial s

ized

so it

will

not

be

easi

ly e

rode

d w

hen

plac

ed o

n th

e sl

ope

of th

e riv

erba

nk. T

he m

ater

ial i

s pl

aced

from

abo

ut th

e riv

er s

ubst

rate

nea

r the

low

-fl ow

wat

er s

urface

up

the

river

bank

to

slig

htly

bel

ow b

ankf

ull e

leva

tion.

Whe

n pl

aced

on

the

non-

vege

tate

d ch

anne

l sub

stra

te b

elow

ban

kful

l ele

vatio

n it

prot

ects

the

toe

of

the

expo

sed

river

bank

and

hel

ps re

duce

futu

re ri

verb

ank

eros

ion.

Thi

s tre

atm

ent h

elps

redu

ce e

rosi

on b

y de

crea

sing

the

river

bank

an

gle.

Thi

s tre

atm

ent c

an b

e sh

aped

to d

efl ect

hig

h w

ater

from

the

river

bank

tow

ard

the ce

nter

of t

he ri

ver.

The

treat

men

t nor

mal

ly

exte

nds

the

leng

th o

f an

erod

ing

river

bank

whe

re a

dditi

onal

rive

rban

k pr

ote c

tion

is n

eces

sary

. Whe

n in

stal

led

prop

erly

this

trea

tmen

t ha

s a

natu

ral a

ppea

ranc

e.



Appendix A

Detailed Information on In-Stream Restoration ActivitiesC.

Des

crip

tions

of b

ould

er tr

eatm

ents

use

d to

redu

ce ri

verb

ank

eros

ion

(con

tinue

d)Ba

nk e

rosi

on

treat

men

tsRe

stor

atio

n tre

atm

ent d

escr

iptio

ns

Boul

der J

Hoo

kTh

is s

truct

ure

is u

sual

ly p

lace

d at

the

uppe

r end

of p

ool h

abita

ts. I

t is cr

eate

d us

ing

3−5

ft bo

ulde

rs a

rran

ged

in a

par

tial u

pstre

am-

faci

ng s

emic

ircle

. It a

lso cr

eate

s a

dive

rsity

of w

ater

dep

ths

and

wat

er v

eloc

ities

, cre

ates

add

ition

al tr

out h

abita

ts, a

nd h

elps

m

aint

ain

adeq

uate

poo

l dep

ths.

The

fi rs

t few

bou

lder

s in

a J

hoo

k st

ruct

ure

redu

ce w

ater

vel

ociti

es a

nd ri

verb

ank

eros

ion.

Exc

avat

ion

of a

poo

l hab

itat i

s us

ually

nec

essa

ry. T

he s

ite fo

r the

fi rs

t bou

lder

is a

long

the

outs

ide cu

rve

whe

re th

e po

ol is

exc

avat

ed. T

he

fabr

ic m

ater

ial i

s pl

aced

whe

re th

e fi r

st b

ould

er is

em

bedd

ed in

to th

e riv

erba

nk. T

he fa

bric

form

s a

seal

bet

wee

n th

e bo

ulde

r and

th

e riv

erba

nk. T

he to

p of

the

boul

der i

s se

t abo

ut 1

2 inch

es a

bove

ban

kful

l ele

vatio

n. T

his

boul

der i

s pl

aced

to d

efl ect

wat

er s

urface

cu

rren

t tow

ard

the ce

nter

of t

he s

tream

. Foo

ter b

ould

ers

are

plac

ed d

irect

ly d

owns

tream

of a

ll bo

ulde

rs p

lace

d to

form

the

J-ho

ok

struct

ure.

Foo

ter b

ould

ers

prev

ent t

he s

truct

ure

boul

ders

from

mov

ing

dow

nstre

am d

urin

g hi

gh ri

ver fl

ow

s. E

ach

boul

der i

n th

e st

ruct

ure

is p

lace

d to

dire

ct s

urface

wat

er fl

ows

tow

ard

the

mid

dle

of th

e st

ream

. The

bou

lder

stru

ctur

e st

arts

at a

n an

gle

of a

bout

30

−40

degr

ees

from

the

river

bank

for a

bout

1/3

the

dist

ance

acr

oss

the

stre

am, g

ently

cur

ves

dow

nstre

am fo

r abo

ut 2

/3 th

e di

stan

ce

acro

ss th

e st

ream

, the

n cu

rves

sha

rply

dow

nstre

am in

to th

e ce

nter

of t

he e

xcav

ated

poo

l. Th

e to

p el

evat

ion

of e

ach

boul

der i

s decr

ease

d an

d th

e ga

p be

twee

n ea

ch b

ould

er incr

ease

s as

the

struct

ure

is c

onst

ruct

ed acr

oss

the

river

.

Boul

der V

ane

(Hal

f cro

ss

vane

)

This

stru

ctur

e us

es th

ree

to fo

ur re

ctan

gula

r sha

ped

boul

ders

rang

ing

in s

ize fr

om 4

−6 ft

and

2−3

feet

in h

eigh

t. Th

e bo

ulde

r van

e po

ints

ups

tream

abo

ut 2

0−30

deg

rees

from

the

river

bank

and

dire

cts

surfa

ce w

ater

cur

rent

s to

war

d th

e ce

nter

of t

he ri

ver c

hann

el.

The

top

elev

atio

n of

eac

h succ

eedi

ng p

lace

d bo

ulde

r dec

reas

es a

nd th

e fi n

al b

ould

er re

sts

abou

t 12−

15 inch

es a

bove

the ch

anne

l su

bstra

te. B

ould

er v

anes

rare

ly e

xten

d m

ore

than

20%

acr

oss

the

river

cha

nnel

. The

hyd

raul

ic ju

mp

betw

een

boul

ders

nor

mal

ly

shou

ld b

e le

ss th

an 1

ft. O

n th

e do

wns

tream

sid

e of

eac

h bo

ulde

r, a

foot

er b

ould

er is

em

bedd

ed in

to th

e ch

anne

l sub

stra

te a

nd p

lace

d tig

ht a

gain

st e

ach

vane

bou

lder

. The

foot

er b

ould

er p

rovi

des

stab

ility

to th

e bo

ulde

r van

e st

ruct

ure

and cr

eate

s ad

ditio

nal t

rout

ha

bita

t.



Appendix A

Detailed Information on In-Stream Restoration ActivitiesD

. Des

crip

tion

of tr

eatm

ents

use

d to

enh

ance

mid

-cha

nnel

aqu

atic

and

trou

t hab

itats

Aqua

tic h

abita

t tre

atm

ents

Rest

orat

ion

treat

men

t des

crip

tions

Rand

om

Boul

ders

Boul

ders

exc

eedi

ng a

bout

3 ft

in le

ngth

and

3 ft

in h

eigh

t, w

ith a

t lea

st o

ne n

early

fl at

sur

face

and

with

an

irreg

ular

rect

angu

lar s

hape

, m

ake

exce

llent

rand

om b

ould

ers.

Firs

t exc

avat

e an

ove

rsize

d ov

al-s

hape

d pi

t for

eac

h bo

ulde

r. Pl

ace

the

fl atte

st s

ide

up. W

hen

a va

riety

of r

ando

m b

ould

ers

are

used

in ri

ffl e

or ru

n re

ache

s, b

ould

er to

p el

evat

ions

sho

uld

rang

e be

twee

n ab

out b

ankf

ull t

o sl

ight

ly

unde

rwat

er d

urin

g lo

w s

tream

fl ow

s. T

he d

iffer

ent b

ould

er e

leva

tions

pro

vide

a d

iver

sity

of w

ater

dep

th a

nd w

ater

vel

ocity

hab

itats

ac

ross

a w

ide

rang

e of

stre

am fl

ows.

Lim

ited

use

of ra

ndom

bou

lder

s in

poo

ls c

reat

es a

dditi

onal

trou

t cov

er. R

iver

s w

ith h

igh

stre

am

trans

porte

d se

dim

ent l

oads

tend

to acc

umul

ate

sedi

men

t on

the

dow

nstre

am s

ide

of b

ould

ers

and

limit

thei

r val

ue a

s tro

ut h

abita

t.

Boul

der C

lust

erLa

rger

bou

lder

s >

5 ft

in le

ngth

and

abo

ut 3

ft in

hei

ght a

re re

com

men

ded

for b

ould

er c

lust

ers.

In ri

ffl e

or ru

n ha

bita

ts, e

xcav

ate

a la

rge

over

size

d ov

al-s

hape

d pi

t lar

ge e

noug

h to

acc

omm

odat

e th

e nu

mbe

r of b

ould

ers

plan

ned

for t

he c

lust

er. A

bou

lder

clu

ster

no

rmal

ly c

onta

ins

thre

e bo

ulde

rs b

ut u

p to

sev

en b

ould

ers

have

bee

n us

ed. T

he e

xcav

ated

pit

shou

ld e

xten

d se

vera

l fee

t bey

ond

the

plan

ned

size

of t

he b

ould

er c

lust

er. B

ould

ers

plac

ed in

a c

lust

er a

rran

gem

ent n

eed

diffe

rent

spa

cing

and

ele

vatio

ns to

cre

ate

a di

vers

ity o

f wat

er d

epth

s an

d ve

loci

ties.

In th

e m

iddl

e of

the cl

uste

r dow

nstre

am fr

om th

e th

ree

or fo

ur m

ost u

pstre

am b

ould

ers,

exca

vate

dee

per i

nto

the ch

anne

l sub

stra

te to

pro

vide

add

ition

al d

eepe

r wat

er tr

out h

abita

t. If

river

tran

spor

ted

sedi

men

t mat

eria

ls

are

min

imal

, a b

ould

er c

an b

e pl

aced

into

the

deep

est w

ater

poc

ket.

Crea

te a

tail

out i

n th

e lo

wer

end

of t

he b

ould

er c

lust

er.

Rock

Gar

den

A rock

gar

den

treat

men

t inv

olve

s em

bedd

ing

boul

ders

less

than

2 ft

in d

iam

eter

into

a s

mal

l/coa

rse

grav

el ri

ffl e

subs

trate

. Thi

s tre

atm

ent i

s su

ited

for s

econ

dary

act

ive ch

anne

ls lack

ing co

ver o

r oth

er in

-cha

nnel

stru

ctur

es. B

ould

ers

are

plac

ed c

lose

eno

ugh

toge

ther

to c

reat

e di

vers

ities

of w

ater

vel

ociti

es th

at p

rovi

de h

abita

t cov

er. T

his

treat

men

t cre

ates

add

ition

al c

hann

el ro

ughn

ess.

Stum

psSt

umps

are

mer

ely

root

wad

s w

ith a

sho

rt tru

nk. T

he ro

ot fa

n sh

ould

exc

eed

3 ft

in d

iam

eter

and

trun

k le

ngth

can

be cu

t to

fi t th

e si

te. S

umps

are

place

d up

right

in lo

w-g

radi

ent r

uns

and

riffl e

s or

in p

ools

with

the

root

fan

rest

ing

on th

e ch

anne

l sub

stra

te. S

tum

ps

are

anch

ored

with

larg

e fl a

t sha

ped

boul

ders

. Thi

s tre

atm

ent i

s no

t sui

tabl

e fo

r hig

h-gr

adie

nt ri

vers

of i

n-st

ream

s w

ith h

igh

sedi

men

t lo

ads.

Mid

Cha

nnel

Ro

ot W

ads

This

stru

ctur

e pr

ovid

es m

id-c

hann

el o

verh

ead

trout

cov

er. M

id-c

hann

el ro

ot w

ads ca

n be

place

d in

to lo

w g

radi

ent r

iffl e

and

run

habi

tats

or p

lace

d in

to e

xist

ing

or e

xcav

ated

mid

-cha

nnel

poo

ls. R

oot w

ads

with

a ro

ot fa

n di

amet

er g

reat

er th

an 3

ft a

nd h

avin

g at

tach

ed tr

unks

> 1

6 ft

in le

ngth

are

place

d pa

ralle

l to

the

river

fl ow

faci

ng th

e ro

ot fa

n up

stre

am. T

his

struct

ure

is a

ncho

red

usin

g fl a

t-sid

ed 3

−6 ft

bou

lder

s pl

aced

on

the

trunk

or r

oot w

ad. W

here

ver p

ossi

ble,

two

root

wad

s sh

ould

be

plac

ed b

esid

e ea

ch o

ther

fo

r bet

ter a

ncho

ring.

Thi

s al

so c

reat

es a

dditi

onal

ove

rhea

d tro

ut c

over

. Dep

endi

ng u

pon

the cu

rvat

ure

of th

e ro

ot w

ad lo

g, th

e do

wns

tream

end

of t

he tr

unk ca

n be

bur

ied

into

the ch

anne

l sub

stra

te a

nd a

ncho

red

usin

g a

larg

e bo

ulde

r.



Appendix A

Detailed Information on In-Stream Restoration Activities

Figure A.1. Reaches 1−4 in the 11-mile reach of the Arkansas River below the confl uence with California Gulch.



Appendix A


Figure A.2. Elevating riffl e substrate.

A.3 In-Stream Restoration Activities Figures A.2−A.9 provide examples of the types of in-stream restoration activities that may be employed.

Figure A.3. Reducing channel width by adding fi ll.



Appendix A


Figure A.4. Creating a point bar.

Figure A.5. Add riparian vegetation.



Appendix A


Figure A.6. Excavate a pool.

Figure A.7. Add overhead trout cover.



Appendix A


Figure A.8. Add a riparian bench with a cobble toe.

Figure A.9. Add a riparian bench with a stone/boulder toe.



Appendix A

Detailed Information on In-Stream Restoration ActivitiesA.4 Bank Erosion TreatmentsFigures A.10−A.18 provide examples of the types of bank erosion treatments that may be employed.

Figure A.10. Log spur.

Figure A.11. Log vane.



Appendix A


Figure A.12. River bank root wad.

Figure A.13. Horizontal parallel log.



Appendix A


Figure A.14. Cross vane.

Figure A.15. Half cross (boulder) vane.



Appendix A


Figure A.16. Boulder J hook.

Figure A.17. Hard point.



Appendix A


Figure A.18. Single boulder defl ector.

A.5 Aquatic Habitat TreatmentsFigures A.19−A.23 provide examples of the types aquatic habitat treatments that may be employed.

Figure A.19. Rock garden.



Appendix A


Figure A.20. Boulder cluster.

Figure A.21. Stump.



Appendix A


Figure A.22. Random boulders.

Figure A.23. Mid-channel root wad/log.

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