20051690 Ver 1_Erosion Evaluation 1_20070803

?-16Qb
EcoScience Corporation
1101 Haynes Street, Suite 101
Raleigh, North Carolina 919-828-3433
EcoScience
MEMORANDUM
TO: George Howard,
Restoration Systems, LLC (RS) AUG 3 2007
FROM: Matt Cusack, EcoScience Corporation
OENR -WATER QUALITY
DATE: July 21, 2006 WETLANDS AND STOMMATER BRANCH
RE: Former Carbonton Dam Erosion Evaluation Number 1 06-277.01
The purpose of this memorandum it to provide you with the results of the first erosion assessment
of the former impoundment of the Carbonton Dam performed in accordance with your Section 401
permit obligations. The former impoundment included 126,673 linear feet of affected stream
reaches that extended throughout portions of Lee, Chatham, and Moore Counties, North Carolina.
This evaluation was performed to document any evidence of erosion within the former
impoundment including but not limited to bank failure, loss of stream bank trees, severe head-cuts,
and the loss or gain of large depositional features.
HISTORY
The North Carolina Division of Water Quality (NCDWQ) Section 401 permit condition #9 associated
with the removal of the Carbonton Dam Deep River Restoration Site requires that a "survey [of] the
present lake bed and its flooded tributaries [shall occur] at least every two weeks (bi-weekly) or
within three days of a rain more than or equal to one inch at Moncure, NC." In order to satisfy
permit condition #9, Restoration Systems, LLC (RS) authorized EcoScience Corporation (ESC) to
conduct weather related erosion evaluations within the former Carbonton Impoundment (ESC
Proposal P06-003 January 13, 2006).
As described in detail within this memorandum, RS and ESC collected historical weather
information that suggested that the permit condition requested by NCDWQ presents several
logistical difficulties. First, no USGS river gauge is present near Carbonton, NC. No publicly
available or trustworthy real-time weather data are available in or around Carbonton, NC. The
nearest weather station to Carbonton is located in Sanford, NC. Second, ESC believes that using
rainfall from one weather station from within the 215-square mile watershed is not properly
indicative of increased river stage conditions within the former impoundment. Thus, ESC has
investigated and developed a new method for determining when a field evaluation should be
performed.
In preparation for these evaluations, ESC has collected two years of nearly continuous daily
precipitation and river stage data. If the permit condition #9 remains as stated, then more than 20
field evaluations would have been required during the period for which ESC collected the correlated
rain/river stage data. It is important to note that many of the one inch rain events do not have a
corresponding rise in river stage. Since the perceived purpose of the NCDWQ permit condition is to
evaluate the former impoundment after increased river stage to monitor for erosion, then a one inch
rainfall event is not the best indicator for the initiation of a site visit. Isolated thunderstorms can
EcoScience Corporation
July 21, 2006
Mr. George Howard
Page 2 of 6
RE: Former Carbonton Dam Erosion Evaluation Number 1
produce large amounts of precipitation in a localized area, without contributing significant rain to the
overall watershed. To monitor multiple weather stations in real-time throughout the watershed to
identify a regional precipitation event is time consuming and not practicable. ESC has observed on
Figure 1 that the greater than or equal to one-inch rain events that generate a corresponding rise in
river stage appear to result in a river stage increase to at least 1500 cubic feet per second (cfs).
Thus, ESC proposes to use the correlation between large, regional rain events that cause more
than
a 1500 cfs reading at the Ramseur gaging station to be the "initiation threshold" for a field
evaluation. ESC estimates that this initiation threshold will occur after a river stage rise equal to ten
percent of bankfull.
METHODS
Following an approximate 2.5-inch rainfall event that occurred in the upstream watershed, a peak in
river stage of over 2400 cubic feet per second (cfs) was recorded at the USGS Ramseur river gage
on April 27, 2006 (Figure 1). Once the 1500 cfs initiation threshold requiring an erosion evaluation
was exceeded, ESC monitored the river stage until the river stage fell below the safe evaluation
threshold of 1000 cfs, which occurred on April 28, 2006. ESC personnel performed the erosion
evaluations on May 1 and 2, 2006. The activities on May 1 included observation points along the
main stem of the Deep River and at accessible points along tributaries that comprised the former
site impoundment,. The activities on May 2 included a survey assessment of the substrate bar
located between NC42 and the former dam location within the Deep River. The duties carried out
on May 1 were required to be completed within within a 72 hour period of April 28. ESC expects to
continue using these methods for future evaluations of greater than 1500 cfs river stage event.s
RIVER TRANSIT EROSION EVALUATION
A two-person team performed a twelve-mile canoe transit of the Deep River. The point of ingress
was the Glendon Carthage Road bridge and the point of egress was the North Carolina Wildlife
Resource Commission boat ramp (Figure 2). The team stopped at the mouth of all credited
tributaries as described in the Mitigation Plan (Restoration Systems 2006) as well as at points along
the river where notable conditions occurred. At each observation point, GPS data was collected for
the location, photography and/or videography was taken, and notes where recorded to describe the
condition.
River Observation Point 1
River Observation Point 1 is located on the Deep River just below the Glendon Carthage bridge
crossing (Figure 2). The observation point occurs up stream of the limits of the credited stream
channel but is included because of the significant volume of bank material that has eroded into the
channel. The bank failure begins approximately 20 feet up from waters edge and has eroded
approximately 3 feet downward (Photo 1).
River Observation Point 2
River Observation Point 2 is located near Monitoring Station 12 at the confluence of the Deep River
and an unnamed tributary (Figure 2). The observation point occurs upstream of the limits of the
credited stream channel, but is included due to the impact of the storm event on a sand bar located
in the outside bend of the Deep River. Stormflow eroded significant portions of the sand bar and
EcoScience Corporation
July 21, 2006
Mr. George Howard
Page 3 of 6
RE: Former Carbonton Dam Erosion Evaluation Number 1
up-rooted herbaceous and woody vegetation leaving behind depression pools and bare soil (Photo
2).
River Observation Point 3
River Observation Point 3 is located near Monitoring Station 11 at the confluence of the Deep River
and an unnamed tributary (Figure 2). Minor bank erosion has occurred within the unnamed
tributary and a minor head-cut has developed at the confluence with the Deep River. Streamflow
has eroded down through the deposited silt sediments of the former impoundment and developed a
more incised channel. The removal of the silt material has uncovered a coarser substrate below
(Photo 3).
River Observation Point 4
River Observation Point 4 is located just downstream of the Norfolk-Southern rail bridge on the
Deep River (Figure 2) and is important because of the severe erosion and loss of bank material that
was observed. River flow is concentrated in the middle bridge span due to rock and debris
constrictions on either side of the river. The concentrated flow discharges towards the outside bank
of the river, resulting in significant erosion in high flow events. Following the storm event, the bank
at this location was nearly vertical with some areas of exposed bedrock (Photo 4). This erosion
feature has not changed since a review of the impoundment in December 2005, which suggests
that the feature has eroded to bed rock and may have stabilized.
River Observation Point 5
River Observation Point 5 is located on the Deep River at the confluence with Lick Creek (Figure 2).
Bank erosion was not an issue at the confluence and there was no evidence of the formation of a
head-cut. Scouring of the silt material within Lick Creek has uncovered a courser substrate below
(Photo 5).
River Observation Point 6
River Observation Point 6 is located on the Deep River at the confluence with McClendon's Creek
(Figure 2). No erosion or bank failures could be seen from the confluence and the majority of the
banks remained well vegetated following the rise in storm flow (Photo 6).
River Observation Point 7
River Observation Point 7 is located on the Deep River at the confluence with Big Governors Creek
(Figure 2). No erosion or bank failures could be seen from the confluence and the majority of the
banks remained well vegetated following the rise in storm flow. A few areas at waters edge showed
signs of scour but the majority of the bank material appeared stable and still intact (Photo 7).
River Observation Point 8
River Observation Point 8 is located near Monitoring Station 5 at the confluence of the Deep River
and an unnamed tributary (Figure 2). A significant head-cut was observed at this confluence and is
depicted in Picture 9. The channel of the unnamed tributary is approximately 6 feet above the level
of the Deep River and the head-cut is slowly carving into the tributary to reduce the difference. The
tributary has very steep banks but no erosion or bank failures were observed. A layer of sediment
remains in the channel (Photos 8-9).
EcoScience Corporation
July 21, 2006
Mr. George Howard
Page 4 of 6
RE: Former Carbonton Dam Erosion Evaluation Number 1
River Observation Point 9
River Observation Point 9 is located on the Deep River at the confluence with an unnamed tributary
on the Knight Cattle Corporation property (Figure 2). A large head-cut is present at the confluence
and severe erosion of the banks was observed. Vegetation is lacking along the banks of the
unnamed tributary and sloughing of bank material is a problem here. Banks are steep and incised.
Sediment material within the unnamed tributary covers any coarse material below and the addition
of eroded bank material adds to the silty layer (see Knight Video).
River Observation Point 10
River Observation Point 10 is located on the Deep River at the confluence with an unnamed
tributary (Figure 2). A steep head-cut was observed at this confluence with significant bank failures.
The height difference between the unnamed tributary and the Deep River is approximately four
feet. Vegetation along the tributary banks is well established but at the knick point of the head-cut,
no vegetation has been able to establish. Erosion and sediment transfer will continue until the
tributary matches the height of the Deep River (Photos 10-12).
River Observation Point 11
River Observation Point 11 is located on the Deep River at the confluence with an unnamed
tributary (Figure 2) near Monitoring Station 27. Moderate erosion was experienced here as a result
of the high storm flow and loss of bank material was observed. A head-cut has formed at the
confluence and sediment transport through the tributary has deepened the existing channel (Photo
13).
River Observation Point 12
River Observation Point 12 is located on the Deep River at the confluence with an unnamed
tributary (Figure 2). A large head-cut has formed at the confluence and bank failure on the right
bank of the tributary has resulted in steep, incised banks. Lack of vegetation on the banks of the
confluence has advanced the transport and erosion of bank material (Photo 14).
River Observation Point 13
River Observation Point 13 is located on the Deep River at the confluence with an unnamed
tributary (Figure 2) near Monitoring Station 2. The banks of the tributary at the confluence are very
steep and two head-cuts have formed. The larger head-cut has extended approximately 20 feet
upstream from the confluence and a second, smaller head-cut has formed at the confluence.
Significant erosion has occurred here and sediment transport has deepened the existing channel
(Photo 15).
River Observation Point 14
River Observation Point 14 is located on the Deep River at the confluence with an unnamed
tributary (Figure 2) near Monitoring Station 23. The banks at the confluence are very steep and
highly eroded, with little to no vegetation. A large head-cut has extended approximately 15 feet into
the tributary, moving sediment out to the Deep River (Photo 16).
River Observation Point 15
River Observation Point 16 is located on the Deep River at the confluence with Line Creek (Figure
EcoScience Corporation
July 21, 2006
Mr. George Howard
Page 5 of 6
RE: Former Carbonton Dam Erosion Evaluation Number 1
2). The south facing bank of the confluence was well vegetated but had a large separation of bank
material towards the Deep River. The opposite bank lacked vegetation and had minor erosion.
Banks within Line Creek are deeply incised and sediment material washed from the channel has
accumulated at the confluence (Photo 17).
LAND TRANSIT EROSION EVALUATION
A two-person team reviewed as many credited tributaries during the daylight hours as possible at
public road crossings and at properties for which Restoration Systems has secured access. Either
a 500 foot reach or 20 bankfull widths of each credited tributary were evaluated at each stop, which
ever was greater. Some long-term monitoring stations were visited that were not on credited
reaches to compare conditions to previous visits in order to further describe the extent of the
flooding event. At each observation point, GPS data was collected for the location, photography
was taken, and notes where recorded to describe the condition.
Land Observation Point 1
Land Observation Point 1 was taken at the crossing of Carbonton Road and Line Creek, a credited
tributary to the Deep River (Figure 2). Signs of increased flow were apparent however no
significant erosion conditions were observed. Sediment deposition was observed within the
adjacent floodplain on leaves and vegetation near the ground surface (Photo 18 and Photo 19).
Beaver activity and debris upstream of the road crossing resulted in a water table height increase
that slowly returned to baseflow elevation without significant flow velocity (Photo 20).
Land Observation Point 2
Land Observation Point 2 was taken at Monitoring Station 45 near the crossing of Cool Springs
Road and McClendons Creek (Figure 2). This section of McClendons Creek is a non-credited
section but was visited to compare the stream condition that was observed the previous week
during monitoring station sampling. Stormflow appears to have been at or near bankfull however
there were no signs of significant bank failure observed. A moderate layer of fine sediment was
observed on streamside vegetation signifying some erosion/sedimentation in the upstream
watershed (Photo 21). Stream channel structure (rock, coarse woody debris, bank trees, etc.) and
composition resembled the condition observed during monitoring station sampling the previous
week.
Land Observation Point 3
Land Observation Point 3 was taken at Monitoring Station 47 near the crossing of Glendon
Carthage Road and McClendon's Creek, a credited tributary to the Deep River (Figure 2). As
expected, signs of more significant stormflow were apparent at Land Observation Point 3 in
comparison to Land Observation Point 2 located further upstream on McClendon's Creek.
Stormflow appears to have been at or over bankfull however there were no signs of significant bank
failure observed. A moderate layer of fine sediment was observed on streamside and floodplain
vegetation signifying erosion/sedimentation in the upstream watershed (Photo 22).
Land Observation Point 4
Land Observation Point 4 was taken at Monitoring Station 40 near the crossing of Steel Bridge
Road and Little Governer's Creek, a credited tributary to the Deep River (Figure 2). This section of
Little Governer's Creek received significant stormflow with overbank flooding apparent in multiple
EcoScience Corporation
July 21, 2006
Mr. George Howard
Page 6 of 6
RE: Former Carbonton Dam Erosion Evaluation Number 1
locations. Sedimentation on leaves and debris within the floodplain was observed over 60 feet from
the stream (Photo 23). Some sections of the bank that were exposed following the dewatering of
the impoundment have begun to slough downslope toward the current lotic water level (Figure 4
and Photo 24-26). However, with the exception of the occasional migration of these bank sections,
no significant bank failure was observed. These areas will be monitored closely to ensure that they
do not undercut the higher bank that was associated with the former impoundment area. Several
small ephemeral-intermittent tributaries were observed to have slight developing head-cuts (Photo
27). These areas have been marked and will be monitored following additional increases in stream
flow.
Land Observation Point 5
Land Observation Point 5 was taken at the crossing of an unnamed road located on the Knight
Cattle Corporation property and an unnamed credited tributary to the Deep River located upstream
of Monitoring Station 29 (Figure 2). Stormflow appears to have reached approximately half bankfull
stage and there were no signs of significant bank failure observed. A thin layer of fine sediment
was observed on streamside vegetation signifying some erosion/sedimentation in the upstream
watershed (Photo 28). At the confluence of the UT and the Deep River, a significant head-cut was
observed. For additional details, see River Observation Point 9 of this document.
SUMMARY
Conditions within the former impoundment of the Deep River and it's tributaries during the first
erosion evaluation (May 1, 2006) ranged from areas with localized severe erosion, to areas with
little to no erosion observed. The majority of all confluences within the former impoundment of the
Deep River were observed to be unstable as a result of a head-cut. The formation of head-cuts is
expected as the former impounded Deep River makes a transition from a lentic to lotic flow regime,
and appropriate sediment transport occurs. Loss of bank material due to storm flow scouring was
observed throughout many tributaries as herbaceous vegetation attempts to re-establish. Banks
within the Deep River were observed to be fairly stable with the exception of treefalls at or near
waters edge. Well established herbaceous vegetation was observed along both banks of the Deep
River below the elevation of the former dam crest pool. Heavily shaded areas have the least
amount of herbaceous vegetation and those areas are experiencing the worst erosion. Woody
debris exposed following de-watering of the former impoundment has collected in numerous
logjams. A single, large, potentially problematic logjam formed behind the NC 42 bridge crossing ,
and RS and NCDOT were notified of this logjam on May 1, 2006. ESC understands that NCDOT
cleaned the log jam from the NC 42 bridge within two days.
SUBSTRATE ISLAND SURVEY
In addition to the erosion evaluation, multiple cross-sections of the substrate island between the NC
42 bridge and the former dam footprint of the Carbonton Dam were completed. Three (3)
permanent cross-sections were established to monitor the character or size of the substrate island
following substantial river stage events. One (1) permanent cross-section was established just
upstream of the former dam to monitor the river profile following high river stage events and to track
movement of the substrate island material (Figure 4). Cross-sectional surveys were completed
using Total Station survey equipment.
EcoScience Corporation
July 21, 2006
Mr. George Howard
Page 7 of 6
RE: Former Carbonton Dam Erosion Evaluation Number 1
RIFFLE ESTABLISHMENT
Following the dewatering of the Carbonton Dam impoundment, several riffles have developed
within the Deep River. These riffles have been observed and documented during field outings.
(Figure 5). Photos 1-6 in Deep River Riffle Establishment Photos section of this document show
the location and character of the newly formed riffles.
DEEP RIVER EROSION EVALUATION FIGURES
(Sa143ul) IleluieN
Cfl 't N O 00 O N O
>' r- O O O O O
>
D
0
w
O
O
L
w
O
O
N
1
14
1
0
a
C
0
0
U
c
a
>
C?
>

90
O
9 s
oQ
/s
90
Q
Off,
9 /1S
OQ
Cj
9
OQ
9
O
9
O
O9
90
O
9
O
O
?/ls
90
9 /n
O
90
.? °o 0 °o 0 O° L° °o 0 °o 0 °o 0 °o 0 ° 90
y 0 N O ti 0 N O ti 0 N O ti 0 N Q?
? M M M N N N N ? r- r- ? /?
bD
w (SIO) OBBIS JGAIM
U
z
Y
U
U
0
v
N
O?
M
0
Pi
z
0 ?Q
xo
a00
o0
0 c
? .s
o?
00
Cb
o?
0
o>
4t >
.Z
c
cn
D U
U
E
Z
0
O U
V ?
?°
oy
°Q
? w
C7 zo
C O n
U O 41 00 O J c c C O y(0 .1 v=i W
_ _ N N
O CL O = o r O O co Z 0
CA &Zz U d N r o L !n O o LL
All,Q O w CD O O V D U Z W W W Q m U
3 v
U a r o o w
� r
0000
0 5
:«IL
LO
• � ;
o
W\ Ww 41dyyy
Lq
CD
cn
i
co
co
EJ
to C a-
q_ 1,
(n70
Q]
�5 Q) % f

A
O
O
C?
_O
C?
O
O
W
?O
O
O
N
i?
U
?i
?r
O
a
e?
b?
O
C
C?
.M
eW
w
r.:1
w
t
r: 1
r?;r
i!
r?-
h
r?1
5D
J
r
C
41 ,
r
G
r-
• r-
?r
r? 1

t
•:1•i

C
• r-
rJ
=r
U O
cc in U) ail Z j W z > N
U > z z O pQQ C Q f v O W
Qo - OU FzQ f
5
IV) W zg 0 = co (a z o Oo
s w0 wQ? p O m _
W U - ?Qy J"Z - y
U c
O
VICE—
O O 011lfOWO WO
W
N
W
W
rl - /11 iG-?.-1 O z N
LC) - O
W O
J N O
r (n
?t•S t{-0 O > >
W o o V o
/ W
N
an o X X
w w
LO) % Q
N U
U1
J W
r
z
w
V)
Q
w
z
O
a
Ld
w
N
z
3 OU
0
z
Of
w
O
!n
Y
0
w
O
z
O
O
Q_ W
N f
.
X
W
'
\
/
1
Y J a
?
? ? h N
z>

m 0 3

a O wD
Y ?
U) U
:2
of w
W Z
Fm0w
LSX W j U 3
O
EE uj 0 a
a

----- z
--------------------- y (L
in A
x ?G ?o
Y t41 . _ i \.
+4'

W
O
} / I
(n N
?w
O W

o
OD
z?
x? af
m
3
Ld N
/ p
Q
O
4 CD
Z
H
N
W
J
O
p09NNM9
0
N
N ?
O
U O
0
W
V1 _
o x
w
a
U
N
0
O
MfO?l 10?fNN??
N t lf 0
? o

i LO
t
o M
O
'
' - F-
Uo
' W
X

w
J
Q
U
0

N N ? ?
0
LD CD LO CD
z
o Fz ? wz
a ?
god ? ]o pp? O
d6J ? v p
20

ti
Z
Q
z
U
r /f
t w .t ?
Al W
N N *??
0 r ?4ti? r
Z U
. ,.ywY
.?j qb
14
?' 4 i
DEEP RIVER EROSION EVALUATION PHOTOS
0
a
a
0
c?
a?
O
s?
a?
0
O

?I
.may
O
U
c?
O
bA ?
U ?
a?
a?
-? Q
? o
o ?
3 .x
0 0
b -0
44
> o
0
coo
a?
Q W
0
o s?,
cC3 U
U ?
Q
3
N
C
O
a
C
O
C?
it
G?
it
N
O
O
S
a
O
O
b
N ?
C U
O >
CC O
c N
bA C
A b
O
O ?
U
c? to
CJ ?
C O
U Cd
> to
U O
N
Q ?
O
O Q-,
c? U
U ?
a Q
M
C
O
C
O
O
a?
cri
0
O
r"
i.
O
c?
r/1
bA
0
O
a.
Cd
a?
c?
b
«3
? bA
b ?
C
? b
> cd
a?" C
N Cd
Q ?
O
.C
+? O
4-4
O U
N
Cd
.,
U
O
0 In
R3 U
U ?
U
? Q

0
a
c
0
s
O
0
O
s
a
ak a,{ ) -? ,:AE 0,
u
bA
b

cd

a?

a?
O >
,

? Q
O
z

o

4-4

s
.

?.
E o

3 -v

o Cd
b

Q ?

0

o Q.

03 U
U ?

a Q
t
kn
C
.Q
C
O
it
U
0
a?
vi
0
O
.C
a
0
In.
coo
C
c?
C
? b
U
U ?
O
.b
0 03
t1. C
U ?
U
Q C8
N N
4. 4-.
O O
? bA
U
cd
O O
U U
c
0
0 Q.
Cl U
U
U
? Q

C
O
C
0
a?
O
a?
?o
0
O
PLO
a?
a?
U
0
b
a?
U
U
o
. r,
O
U
U O
A
bU
U ?
Q O
O
E
o
a?
03
o
U v?
0
o Q.
4
c?i U
U ?
N
? Q
C
O
C
0
e?
i.i
U
0
a
0
O
.C
a

v
b, .
?f

0011k '

U
U
s-.
O
r7
0
0
(? O
b ?
? O
? O
N
Q O
0 3
Q cd
? N
O ?
U v?
0
o ?.
Cd U
U /?
00
O
C
0
Cd
>
i.
6>
a?
00
0
0
a
b
bb u

0

d
kr) U

b
.?:

o
U N

C? ?3
?
cn bb
03
0

o ?.

? U
U v?

Q
0
00
C
o
C
O
c?
it
Co
>
O
O
a
O
ct
U
coo

C
O
cd
U
O

;, a)
cd
A
03
o
'.?
I
O
bA

O
O
-0 C/) O
S"' rO U ? U

O
U
a)
Q
a?
U
U
O
O
U
0
C
'o
0.
C
0
,Lr
0
0
O
QI
cd
..d
a?
c?
cti
b
IZ
c?
a?
a? cd
Q
a?
cd
o ?
? o
U to
N ?
b0
O o
U v?
0
o u.
c? U
U ?
U
Q
O
C
O
PLO
c
0
>
it
W
a?
a
0
O
a

A,? 4k
C
a
{
a l ..
ti
Imo:

c?
b
a?
Cd
A
c?
b
> b
04 73
Q O
a?
b
CIS
o ?
U U
U 'b
N N
? U
bA
U a
0
C? U
U v?
U
0
'o
0
O
a?
R

03
o
3 b
0
0

U b
m
>
R?

.?
C
con
?
eli c
0

..C 03
U
o

0
U
CIO
N
Q
U
cC
a?
C
O
a
C
O
a?
>
ri
0
O
a
N
O
cd
bA
O
O
s.,
cd
U
cC
b
cd
cd
?
C's C,3
'b
?. cd
U ?
O
N v?
Q ?
U U
4-1
O
N to
N ?
U
O N
U x
0
c
o
cl u
U ?
U
Q
N
C
O
a
C
O
C?
,L0
0
a
cd
..d
a?
c?
C
CIS
b a?
Q C,3
cl
a? x
c,3
U O
N ?
Q O
? O
O N
U ?
U ?
U ?
? U
4-4
O
U x
0
o a.
c? U
U ?
U
? Q
M
C
O
C
O
e?
0
a?
0
O
a
CA
Q

,?

C N

O
C

'O 0

O
?
?

N

•?
C

? tU
4.1

cd
O
0

o a..

cCi U
U v]
O U
? Q
7
C
O
a
c
0
e?
Sr
0
i,
0
O
M
N
O
cd
cn
bA
O
O
O
O
cd
Oa
cd
cd
N N
.0
? O
cd O
? O
O
U
0. 'C3
N ?
Q to
O U
U Cd
? N
? U
? N
O >
U v?
0
cd U
U ?
U
h-.? Q
'o
0.
C
0
c?
U
U
0
O
a?
a,
U
U
a
b
C
>
a?
Q ?
U ?
o
4--4
o
U ?
? U
U ?
? U
O ?
O
0 Q.
a3 U
U v1
U
t-? Q
A
C
'o
C
0
e?
O
a
00
0
O
a

bA , ?
? o
O O
U
U
U ?
a?
U
cd
? O
O ?
O c?
? O
o 'd
? o
cd
3 ?
Q H
c
0
o 4
? U
U ?
U
? Q
0
'o
a
0
O
b
c
a
o?
0
O
a
b4
O
U ?
x O
N ?
U ?
?. U
U ?
b ?
b ?
cd
0 0
0 0
U O
? b
o ?
cd
a?
? H
0
o Q.
c? U
U ?
U

C
•O
C
O
?s
C
C?
a
O
N
O
O
?I

W .L

rg,
t
a
I
t

4 ?y
? 1 X'A
a
s
P
? ?1 t

t r ? ?

s ;

v
J
'
4 ? y
2

?u
a 6

b
G?
IZI
O
O
O ?
U
bA
N ?
a?
a?
lV
?11
R: v
O ?
? "C3
O
cts 3
CIS
? U
Q
U ?
? Q
N
?i
•O
O
?O
V.yy
Fn
a
N
O
O
a
F
1 - y y 1• ? RT
f
y
K
„ .,
PI

i? F HMI,

' k
t. e 'tom.
*4ti i'
y? 1
? y'k

?
YY
1 r

Arl rr

• ,jCT

7 ,t-

r

C?
t ! ?I••11
CIS I••1
O .l./
.ry
cn
? O
^? b
r
? U
?r
p
U
U5 -d
0
• r-I
0
cd U
U
a Q
M
C
O
PLO
C
O
O
b
C
N
N
O
O
0
O
. r,
cd
N
to
a?
b
A
cd
A
cd
? cd
O a?
cd v?
? O
•? O
b
L
a?
cd 'd
X 4"
? O
U ?
c cd
O
cd
U -d
U O
O
O ?.
C U
U v?
N
Q
C
'o
a
C
O
it
U
'C
C
C
a
M
N
O
O
z~
a?
03
a?
a,
O
U
bA
S~
O
U
c?
O
U
by
s..
N
N ^'
O
in,
O
O
cz Cl V')
.? j
cd O
? 3 a
7°
a?
U
? U O
b O
O
? U
b
O U
cn
A
O
O ?1
cC U
U v]
Q
Itt
C
'o
a
C
O
0
^C
O
N
O
O
a
O
O
O
Cd
b4
0
0
0
Cd
N
0.
1
cd
U
N
a?
v
N
N
O
A
O
cd
U
O

a?
>
cd
41-
f
U
b
O
O~
a?
O
bA
U
cl
3
a?
b
to
3
O
t-°
cd
cd
O
a?
4-4
O
O
U
U
cn
.d
U
O
N
U
O

O
4-
U
U
Q
U
3
U
_O
U
N
b
3
0
bk
O
O
O
b?
U
4.0
C
0
a
C
O
C?
W
0
^C
O
C?
N
O
4-0
O
O
d'
O
cd
CA
to
0
O
0
03
U
c?
U
N
U
a.
N
U
O
N
O
O
c?
U
O

a?
c?
O
a?
.b
A
O
O
P.,
a?
44
O
bA
O
a?
3
-b
ao
3
0
C?
cl
U
a.,
U
4-i
O
O
U
U
b
U
cn
O
Q.,
U
N
O

O
U
U
Q
a?
a?
3
U
O
A
N
U
N
.i:
b
3
0
O
O
O
O
O
b?
U
C
0
a
0
a?
O
b
c
a
N
O
O
a
S4
a?
U
U
O
b
O
U
U
7d
rA
to 5
O O
? U
"d N
U cd
bA ?
? O
?Q
U N
0 0
? -d
a?
crs
? ao
? O
U ?
? o
a?
a? 03
Vl
0
O O~
cC3 U
U V1
U
Q
O
a
0
0
O
b
a
a
N
O
O
a
C) ?
o
i .°
bn ?
o •?
o
cd
a?
c
bA
U
U N
U ?
bb
rn
>
o
C7 0
a Q
0
o ?.
cct U
U v?
? Q
kn
0
a
c
0
a?
O
a
06
N
O
O
.C
a
O
c?
a?
bA
a?
b
A
c?
a?
.b
N ?
A ?
N
O ?
b'° 3
? o
o ?
o ?
C o
W
a
a?
u. Cd
E
o ?
? Q
0
c? U
U ?
U
a Q
_U
a
DEEP RIVER RIFFLE ESTABLISHMENT PHOTOS
r+y j, ?t '? t S 'r { t
'rill
nt ?s f R a?
j7
,It? i` kl' y
t
jo?
tio
".'. ?' r R t e s t r. st + t `'
4
yd ?? r 1 I
r
s
'tt
U
a
3
z
N
O
O
r1i
a
O
O
c?
bA
A
0
. r,
A
O
cd
c?
b
a?
cd
O
O
cd
3
U
U
14-4
O
U
N
4-.
O
c?
U
CIO
O
U
Q
O
cd
U
O
r-l
a
z
ri
0
0
a

7
I

r
ff !/I
i ,

r ?
4 1} a
+??? I ?. 1 1fC?r '
N
J

i
0

r.

%h
. `mob
3 N
?ga h dPr :> .. :
W ?LL
4 ? 1.-
Af
y..i
rr x'

0
Cl
COO
an
0
0
a?
Cc
U
U
O
U
N
1N
^^??1
^W
W
I"?1
U
O
?-4
. fsa_:

•AAW
k
a tV
5 Y
P`PntV
's
r'.

M
N
O
. r.
cC
bA
A
s.,
O
O
03
cti
N
c?
S~
cd
U
O
O
Q
O
U
c3
i?
a?
Q
0
U
O

00
U
E.
a
z
O
0
a

i"
t
II ry f
3? i
p A ?
pp

U
U
s..
U
a?
3
U
N
14-4
O
U
N
CIS
i-r
U
Q
0
cd
U
O