HomeMy WebLinkAboutMemo Response to 04-06-2018 email Memorandum
Western Federal Lands Highway Division
610 E. Fifth Street
Vancouver, WA 98661-3801
TO: Juliana Houghton, Jess Jordan US Army Corps
of Engineers In Reply Refer to: HFL-17
FROM: Steve Morrow, FHWA Western Federal Lands
DATE: May 29, 2018
SUBJECT: NWS-2015-229 Compensatory Mitigation Plan
Review
Thank you again for your prompt and thorough review of the Updated Wetland and Stream
Mitigation Report for the Upper Hoh River Road Bank Stabilization Project dated March 2018. I
hope you found the information contained in the Report to be helpful in understanding the scope of
the project as well as potential effects and mitigation.
This memo provides responses and clarifying information to the comments and concerns identified in
your April 5, 2018 email.
Comment 1. Duration of mitigation monitoring and maintenance. The wetland mitigation proposal
looks sufficient overall, but the monitoring/maintenance should be for 10 years instead of 5. Stream
mitigation monitoring/maintenance should be for 15 years or longer. This is because although
preservation as a mitigation strategy actively preserves a critical habitat in the system, there is a
passive component to it that demands a longer time period of monitoring to ensure viable success.
Response: The monitoring/maintenance period for the wetland compensatory mitigation site
was proposed to be 5 years, consistent with the permit conditions of similar projects: SR 20
CED on Skagit River (NWS-2010-0783) and Oroville Road on Puyallup River (NWS-2012-
0106-WRD). The monitoring/maintenance period for the ELJ/dolosse structures along the
Upper Hoh River Road was proposed for 10 years, and is consistent with the permit conditions
for NWS-2010-0783 and NWS-2012-0106.
Comment 2. Site selection rationale. Please provide more language and information that supports the
187 acres associated with the side channel preservation. The mitigation plan needs to have some sort
of analysis informing this approach as the best mitigation proposal for the impact. We discussed this
in the field and requested that using aerial photography (and potentially real on-the-ground data) you
illustrate what side channel, riparian/wetland floodplain habitat was in existence in the past X number
of years, what the loss has been over the last X number of years (show us the rate of loss), and what
amount of this side channel rearing habitat and riparian/wetland floodplain habitat is left. This would
better demonstrate why the preservation of this habitat type is appropriate mitigation. We still require
the mitigation to be successful to compensate for impacts to the waterbody.
Response: As described in Section 6.2 of the Compensatory Mitigation Plan, the selection of the
proposed mitigation to try to preserve or at least sustain, off-channel habitat in the area near
Mile Post 6.7 and Lindner Creek was initially proposed by, and then endorsed by, WDFW and
Hoh Tribe Fisheries Biologists who monitor and co-manage the fisheries resources of the Hoh
River. Getting a precise quantity in acreage of side channel habitat lost over a period of time
on the Hoh River is really not feasible. Off-channel habitats are small tributaries, frequently
spring or ground water-fed, that flow into larger channels. Their diminutive size cause them to
be overlooked in inventories and they don’t often appear on topographic maps or aerial photos.
Although small, these waters can be very productive for salmonids especially coho salmon and
trout (Smith, 2002). These species are naturally attracted to these sites primarily for protected
over-winter rearing. Requests for data were made to WDFW and Hoh Tribe but no data on the
extent of these features appears available.
Further rationale to the selection of this site is that this identified area is at risk to an
avulsive/channel changing event. Attachment A at the end of this Memo is from the 2004 USBR
Geomorphic Assessment of the Hoh River and is a series of aerial photos from 1939 to 2002 that
map the channel movement on the Hoh River between River Mile 23 to River Mile 25. You will
note, the main channel (low flow channel) went right through the proposed mitigation area in
1971 and 1994. The river will avulse or migrate through this area again as the vegetation on this
floodplain is mostly small willow and alder trees and do not have the necessary floodplain
roughness to resist channel avulsion or migration. The Project’s Proposed Mitigation of log
jams (“channel plugs”) to resist river avulsion is located just upstream of the star – MP 6.7.
Existing side channels and overflow channels already convey water during floods and offer a
path of least resistance when the existing bankfull discharge is exceeded. These channels were
identified as having the highest risk of capturing the main channel in the near future (USBR
2004).
Within Comment #2 you requested we provide aerial photography/graphics that “illustrate
what side channel, riparian/wetland floodplain habitat was in existence in the past X number of
years, what the loss has been over the last X number of years (show us the rate of loss).” The
extent and permanency of high-value side channel aquatic habitat has been in an increased
state of flux in recent years in the Upper Hoh River basin due to increasingly frequent channel
migration and avulsions. Channel migration and avulsion tend to simplify available habitat,
with habitats converting from one type to another, rather than a “loss” of habitat. Figure 3 in
the May 2018 Wetland and Stream Mitigation Report for the Upper Hoh River Road Bank
Stabilization Project shows the change in acreage of four habitat types over the past 12 years as
the result of these frequent channel migration and avulsions.
Comment 3. Contingencies.
a. Mitigation site failure. What if an avulsion event occurs and there is total loss or partial
loss of the mitigation site? How do you intend to recapture mitigation of this kind if the preserved
habitat is lost?
Response: The Hoh River avulsing through the proposed mitigation area is a real possibility, as
evidenced in the USBR report it has happened multiple times since 1939. The intent of the
mitigation is not to preserve 187 acres of floodplain habitat as that implies the habitat is fixed,
static and will remain at 187 acres. There will be events that cause the river to overtop and flow
across these flood channels, the acreage of flooded backwater, early succession forest, mature
forest, etc. will change over time as succession occurs. The engineered log jam structures are
there to provide the necessary roughness to resist the river from capturing it as the main
channel (low flow channel). The metric to measure success or failure should be something that
is observable, quantifiable and demonstrates to be relatively stable over time. The proposed
mitigation plan identifies 25 engineered log jam structures to be installed to resist channel
avulsion. A more quantifiable metric to document success or failure should be documentation
over 15 years of monitoring of the engineered log jams resisting avulsion by a maintaining a
performance standard of over 80% (>20 ELJs) remaining intact and functioning to rack wood
and debris and sediment deposition for riparian vegetation to form upon. Performance
Standard 8 in the Compensatory Mitigation Plan commits that the channel plugs will remain
“intact and structurally functional” during the monitoring period. This standard will be
measured using visual observation. FHWA suggests that this performance standard be
modified to include a quantifiable element, such as what was suggested above or, for instance,
at least 80% of wood pieces in each channel plug remain intact and functional. As defined in
the May 2018 Wetland and Stream Mitigation Report for the Upper Hoh River Road Bank
Stabilization Project; “functioning” will mean that based on visual inspection, key deflector
pieces remain anchored, plugs are collecting woody debris, sediment deposits are evident in and
around the plugs, and that restoration plantings downstream of structures and within the
structures are growing.
We acknowledge the project does alter aquatic habitat, and that alteration must be mitigated
for. However, there seems to be a presumption the ELJ/dolosse permanently eliminates aquatic
habitat, provides no habitat values and therefore is not self-mitigating. The proposed
ELJ/dolosse structures would occupy 1.15 acres of Hoh River aquatic habitat, but that aquatic
habitat is not permanently eliminated. When installed, the ELJs will provide habitat for rearing
and overwintering juvenile salmonids as well as holding habitat for migrating adult salmonids.
Recent 5-year monitoring results of 21 ELJs (containing 881 pieces of LWD) placed as stream
bank protection along the Elwha River concluded ELJs provided significant habitat
improvement for juvenile and adult salmonid species with the proportion of juvenile Chinook
(50-100 mm) in ELJ units consistently greater than in non-ELJ units for both summer and
winter sampling events (McHenry et. al. 2007). The ELJs on the Elwha also affected spawning
habitat by changing the particle size distribution from large and medium cobble to medium and
fine gravel where Chinook, chum, coho and steelhead were directly observed on the formed
gravel deposits. Peters et al. (1998) found juvenile coho salmon densities at banks stabilized
with LWD are generally greater than those stabilized using riprap in western Washington
rivers. The ELJs/dolosse are designed to resemble natural logjams and create considerably
more wood surface area (nine times) and interstitial spaces (five-fold) over traditional ELJs,
providing significantly more habitat complexity over current conditions (CardnoEntrix 2010).
Coe, et. al. (2009) found aquatic communities often occur in greater densities and diversity at
locations associated with wood.
b. Dolosse movement. The contingency plan needs to include what actions would be taken to
remedy the situation if a structure moves (pivots, shifts, sinks, etc.). Whether or not this component is
in the mitigation plan, we would add a special condition to the permit that if the dolos move (more
than a specific amount), they would be moved back into the permitted location.
Response: In the event an individual dolo breaks away from the ELJ and rotates out into the
river such that it potentially becomes a navigation hazard, the dolo will be retrieved and
attached back to the ELJ mass. Western Federal Lands Highway Division (WFLHD) has a
Reimbursable Agreement (RA) with Jefferson County. This RA can be modified to cover
maintenance costs incurred by Jefferson County to retrieve any wayward dolosse.
c. LWM loss. Incorporating a large amount of LWM is critical to minimizing the impacts of the
dolos. How will you address a structure if all the LWM is lost from a structure and it does not wrack
wood appropriately?
Response: There appears an assumption that no additional large wood material will rack
up/accumulate over time to replace the large wood material that rots or breaks up and is lost
over time. The project team is confident that after installation, the ELJs will rack and recruit
large wood material. The physical modeling studies conducted at the Turner-Fairbanks
Hydraulic Research Center have corroborated this. Additionally, there are similar projects: SR
20 CED on Skagit River (NWS-2010-0783), Oroville Road on Puyallup River (NWS-2012-0106-
WRD) and Lower Germany Creek Habitat Enhancement (NWS-2011-0441) all use ELJ/dolos
for bank stabilization. Monitoring reports generated for the three projects document all three
projects are recruiting large wood material and have incurred no losses of large wood attached
to the dolos. A long-term study on the Elwha River by McHenry et.al. (2007), as well as the
Queets River by Abbe and Montgomery (2003) concluded levels of racked large wood on
installed ELJs are increasing over time.
Other studies (Daley, J. and Brooks, A.P. 2013) and published guides (Large Wood Manual by
USBR & USACE (2016) and the Pacific NW Large Woody Material Risk Based Design
Guidelines USBR 2012) on ELJ projects conclude the uppermost layers of material in the ELJ
is at highest risk to be lost (“peeled off”) during high flow events, esp. events that overtop the
ELJ. Therefore, to address your concern in comment 3.c. regarding wood loss, design and
constructing the ELJ above 100-year flood height and appropriate anchoring measures are the
key to retaining the upper layers and has been incorporated into the project.
As stated in Section 7.1.5 of the Compensatory Mitigation Report, Performance Standard 5
requires that the ELJs have a net positive effect for wood recruitment. To better document and
demonstrate large wood material recruitment, material accumulated at each of the in-channel
ELJs will be measured and recorded on a field data form. Newly recruited pieces greater than
12 inches in diameter and 10 feet in length that can be identified in the field will be measured
and noted. A brief summary of wood recruitment or loss at each of the in-channel ELJs will be
drafted as part of the annual monitoring report and documented by field notes and the photo
monitoring comparisons to the previous year’s photos.
Comment 4. Natural materials in mitigation area. Please use hemp rope or twine or other natural
materials to wrap the log bundles in the mitigation area instead steel chain. This would improve the
function of the mitigation site to reduce the amount of fill material remaining in perpetuity after the
log bundles decompose.
Response: the combination of wet-dry climate of the Olympic Peninsula and
photodecomposition from sunlight; combined with periods of inundation and the forces applied
(twisting, vibration, shifting, etc.) by the current and log buoyancy would result in hemp rope
breaking within a few seasons. The intent for these ELJs is to last 50+ years so natural riparian
vegetation can grow large enough to resist a lot of this erosive energy. As discussed previously
in #3c, the top layers of the ELJ are at a higher risk to be “peeled off”, is also the most exposed
to alternating wet-dry conditions and sunlight. Furthermore, the Hoh River has a high level of
recreational use, the risk and liability potential incurred by creating navigational hazards that
are the result of failed hemp rope attachments is too high.
Citations
Abbe, T., J. Bountry, L. Piety, G. Ward, M. McBride and P. Kennard. 2003a. Forest influence on
floodplain development and channel migration zones. Geological Society of America Abstracts with
Programs, Cordilleran Section, 28(5), 41
Abbe, T.B. and D.R. Montgomery. 2003. Patterns and processes of wood debris accumulation in the
Queets River basin, Washington. Geomorphology 51, 81-107.
CardoEntrix. 2010. Skagit River Bank Protection 60% Design Support: SR 20 and Milepost 100.7.
June 27, 2011. Prepared for Washington State Department of Transportion, Burlington, WA.
Coe, H.J., P.M. Kiffney, G.R. Pess, K.K. Kloehn, and M.L. McHenry. 2009. Periphyton and
invertebrate response to wood placement in large Pacific coastal rivers. River Research and
Application 25:1025-1035
East, A.E., Jenkins, K.J., Happe, P.J., Bountry, J.A., Beechie, T.J., Mastin, M.C., Sankey, J.B., and
Randle, T.J., 2017, Channel-planform evolution in four rivers of Olympic National Park, Washington,
U.S.A.: the roles of physical drivers and trophic cascades: Earth Surface Processes and Landforms, v.
42, p. 1011–10
McHenry, M., Pess, G., Abbe, T.B., Coe, H., Goldsmith, J., Liermann, M., McCoy, R., Morely, S.,
and Peters, R. 2007. The Physical and Biological Effects of Engineered Logjams (ELJs) in the Elwha
River, Washington. Salmon Recovery Funding Board (SRFB) Interagency Committee for Outdoor
Recreation (IAC).
Peters, R.J., B.R. Missildine, and D.L. Low. 1998. Seasonal fish densities near river banks
stabilized with various stabilization methods: First year report of the flood technical
58 assistance project. Miscellaneous Report. Western Washington Office, U.S. Fish and
Wildlife Service, Olympia, Washington.
Piety, L. A., Bountry, J. A., Randle, T. J., and Lyon E. W. (2004). “Geomorphic assessment of
the Hoh River, Washington, river miles 17 to 40 between Oxbow Canyon and Mount Tom
Creek,” U.S. Department of the Interior, Bureau of Reclamation, Denver, Colorado.
Smith, Carol J. 2000. Salmon and Steelhead Habitat Limiting Factors in the North Coastal Streams of
WRIA 20. Washington State Conservation Commission, Lacey, Washington State.
Attachment A
8
7
6
To
w
e
r
C
r
e
e
k
Co
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
25
24
23
8
7
To
w
e
r
C
r
e
e
k
Co
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
25
24
23
8
7
To
w
e
r
C
r
e
e
k
Co
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
25
24
23
8
7
To
w
e
r
C
r
e
e
k
Co
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
25
24
23
8
7
To
w
e
r
C
r
e
e
k
Co
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
25
24
23
To
w
e
r
C
r
e
e
k
Co
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
8
7
25
24
23
Fi
g
u
r
e
4
6
.
C
h
a
n
g
e
s
i
n
t
h
e
l
o
w
-
f
l
o
w
c
h
a
n
n
e
l
f
o
r
t
i
m
e
i
n
t
e
r
v
a
l
s
s
i
n
c
e
18
9
5
f
o
r
a
s
e
c
t
i
o
n
o
f
t
h
e
M
o
r
g
a
n
s
C
r
o
s
s
i
n
g
R
e
a
c
h
b
e
t
w
e
e
n
R
M
2
3
an
d
R
M
2
5
,
i
n
c
l
u
d
i
n
g
C
o
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
.
20
0
2
19
8
1
19
9
4
19
6
0
19
5
0
19
3
9
8
7
To
w
e
r
C
r
e
e
k
Co
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
25
24
23
19
3
9
L
o
w
-
f
l
o
w
C
h
a
n
n
e
l
19
5
0
L
o
w
-
f
l
o
w
C
h
a
n
n
e
l
Lo
w
-
w
a
t
e
r
c
h
a
n
n
e
l
h
a
s
b
e
c
o
m
e
m
o
r
e
si
n
u
o
u
s
a
n
d
h
a
s
m
o
v
e
d
d
o
w
n
s
t
r
e
a
m
Ch
a
n
n
e
l
p
o
s
i
t
i
o
n
i
s
f
i
x
e
d
a
t
th
e
s
e
t
w
o
l
o
c
a
t
i
o
n
s
,
b
u
t
i
s
mo
r
e
s
i
n
u
o
u
s
d
o
w
n
s
t
r
e
a
m
19
6
0
L
o
w
-
f
l
o
w
C
h
a
n
n
e
l
19
7
1
L
o
w
-
f
l
o
w
C
h
a
n
n
e
l
Lo
w
-
f
l
o
w
c
h
a
n
n
e
l
i
s
a
l
o
n
g
th
e
C
o
u
n
t
y
R
o
a
d
19
8
1
L
o
w
-
f
l
o
w
C
h
a
n
n
e
l
19
9
4
L
o
w
-
f
l
o
w
C
h
a
n
n
e
l
Mo
v
e
m
e
n
t
o
f
m
e
a
n
d
e
r
s
i
s
l
i
m
i
t
e
d
20
0
2
L
o
w
-
f
l
o
w
C
h
a
n
n
e
l
19
3
9
H
C
M
Z
B
o
u
n
d
a
r
y
HC
M
Z
B
o
u
n
d
a
r
y
19
8
1
H
C
M
Z
B
o
u
n
d
a
r
y
19
9
4
H
C
M
Z
B
o
u
n
d
a
r
y
19
7
1
H
C
M
Z
B
o
u
n
d
a
r
y
19
5
0
H
C
M
Z
B
o
u
n
d
a
r
y
19
6
0
H
C
M
Z
B
o
u
n
d
a
r
y
In
1
8
9
5
,
a
m
e
a
n
d
e
r
i
n
t
h
e
c
h
a
n
n
e
l
w
a
s
a
t
i
t
m
a
x
i
m
u
m
e
x
t
e
n
t
o
n
r
i
v
e
r
r
i
g
h
t
up
s
t
r
e
a
m
o
f
C
o
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
.
I
n
1
9
3
9
,
t
h
e
l
o
w
-
f
l
o
w
c
h
a
n
n
e
l
w
a
s
no
t
n
e
a
r
C
o
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
.
T
h
e
c
h
a
n
n
e
l
w
a
s
m
o
r
e
b
r
a
i
d
e
d
a
n
d
st
r
a
i
g
h
t
e
r
t
h
a
n
i
t
i
s
i
n
s
u
b
s
e
q
u
e
n
t
y
e
a
r
s
a
s
s
h
o
w
n
o
n
t
h
e
a
v
a
i
l
a
b
l
e
a
e
r
i
a
l
ph
o
t
o
g
r
a
p
h
s
.
By
1
9
5
0
,
t
h
e
m
e
a
n
d
e
r
i
n
t
h
e
l
o
w
-
f
l
o
w
c
h
a
n
n
e
l
t
h
a
t
w
i
l
l
e
v
e
n
t
u
a
l
l
y
m
o
v
e
ou
t
w
a
r
d
t
o
f
l
o
w
a
l
o
n
g
C
o
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
h
a
s
j
u
s
t
b
e
g
u
n
t
o
d
e
v
e
l
o
p
ne
a
r
R
M
2
4
.
T
h
e
m
e
a
n
d
e
r
n
e
a
r
R
M
2
5
h
a
s
m
o
v
e
d
o
u
t
w
a
r
d
s
i
n
c
e
1
9
3
9
.
In
1
9
6
0
,
t
h
e
m
e
a
n
d
e
r
s
i
n
t
h
e
l
o
w
-
f
l
o
w
c
h
a
n
n
e
l
a
t
R
M
2
5
a
n
d
b
e
t
w
e
e
n
R
M
2
3
an
d
2
4
h
a
v
e
m
o
v
e
d
o
u
t
w
a
r
d
,
a
n
d
t
h
e
l
o
w
-
f
l
o
w
c
h
a
n
n
e
l
i
s
m
o
r
e
s
i
n
u
o
u
s
t
h
a
n
it
w
a
s
i
n
1
9
5
0
.
By
1
9
7
1
,
t
h
e
m
e
a
n
d
e
r
b
e
t
w
e
e
n
R
M
2
3
a
n
d
2
4
h
a
s
m
o
v
e
d
o
u
t
w
a
r
d
t
o
f
l
o
w
al
o
n
g
t
h
e
H
C
M
Z
B
o
u
n
d
a
r
y
a
t
C
o
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
.
T
h
e
m
e
a
n
d
e
r
s
t
a
y
s
ap
p
r
o
x
i
m
a
t
e
l
y
i
n
t
h
i
s
p
o
s
i
t
i
o
n
t
o
a
t
l
e
a
s
t
2
0
0
2
b
e
c
a
u
s
e
m
e
a
n
d
e
r
m
o
v
e
m
e
n
t
is
l
i
m
i
t
e
d
b
y
t
h
e
C
o
u
n
t
y
R
o
a
d
.
By
1
9
8
1
,
t
h
e
m
e
a
n
d
e
r
a
t
C
o
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
h
a
s
m
o
v
e
d
o
u
t
w
a
r
d
o
n
l
y
sl
i
g
h
t
l
y
s
i
n
c
e
1
9
7
1
.
By
1
9
9
4
,
m
o
v
e
m
e
n
t
o
f
t
h
e
t
w
o
m
e
a
n
d
e
r
s
o
n
r
i
v
e
r
r
i
g
h
t
,
o
n
e
n
e
a
r
T
o
w
e
r
C
r
e
e
k
an
d
o
n
e
a
t
C
o
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
,
i
s
l
i
m
i
t
e
d
b
y
t
h
e
C
o
u
n
t
y
R
o
a
d
a
n
d
(
o
r
)
t
h
e
va
l
l
e
y
e
d
g
e
.
By
2
0
0
2
,
r
i
p
r
a
p
h
a
s
b
e
e
n
a
d
d
e
d
t
o
C
o
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
.
T
h
e
t
w
o
me
a
n
d
e
r
s
o
n
r
i
v
e
r
r
i
g
h
t
a
r
e
s
t
i
l
l
l
o
c
k
e
d
i
n
t
o
t
h
e
i
r
p
o
s
i
t
i
o
n
s
a
s
t
h
e
y
w
e
r
e
by
1
9
9
4
.
Th
e
p
o
s
i
t
i
o
n
o
f
t
h
e
c
h
a
n
n
e
l
i
s
f
i
x
e
d
a
t
th
e
m
o
u
t
h
o
f
S
p
r
u
c
e
C
a
n
y
o
n
19
7
1
Fi
r
s
t
t
i
m
e
s
i
n
c
e
1
8
9
5
t
h
a
t
w
e
s
e
e
th
e
l
o
w
-
f
l
o
w
c
h
a
n
n
e
l
i
s
a
d
j
a
c
e
n
t
to
C
o
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
Mo
v
e
m
e
n
t
o
f
m
e
a
n
d
e
r
s
i
s
l
i
m
i
t
e
d
18
9
5
C
h
a
n
n
e
l
Fi
g
u
r
e
4
6
Be
g
i
n
n
i
n
g
o
f
m
e
a
n
d
e
r
t
h
a
t
e
v
e
n
t
u
a
l
l
y
m
o
v
e
s
o
u
t
w
a
r
d
an
d
d
o
w
n
s
t
r
e
a
m
t
o
C
o
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
1,
0
0
0
0
1
,
0
0
0
2
,
0
0
0
Fe
e
t
Se
c
t
i
o
n
a
l
o
n
g
w
h
i
c
h
l
o
g
j
a
m
s
w
e
r
e
co
n
s
t
r
u
c
t
e
d
i
n
1
9
9
8
a
n
d
2
0
0
3
8
7
5
6
Re
d
C
r
e
e
k
To
w
e
r
C
r
e
e
k
Co
u
n
t
y
R
o
a
d
S
i
t
e
M
P
6
.
7
Mi
n
n
i
e
P
e
t
e
r
s
o
n
C
a
m
p
g
r
o
u
n
d
25
24
23
22
21
Fi
g
u
r
e
4
7
.
A
r
e
a
s
w
h
e
r
e
t
h
e
u
n
v
e
g
e
t
a
t
e
d
c
h
a
n
n
e
l
h
a
s
e
x
p
a
n
d
e
d
s
i
n
c
e
1
9
3
9
i
n
t
h
e
M
o
r
g
a
n
s
C
r
o
s
s
i
n
g
R
e
a
c
h
.
T
h
e
n
e
w
l
y
a
c
t
i
v
e
a
r
e
a
s
a
r
e
t
h
o
s
e
f
i
r
s
t
vi
s
i
b
l
e
a
s
p
a
r
t
o
f
t
h
e
u
n
v
e
g
e
t
a
t
e
d
c
h
a
n
n
e
l
i
n
t
h
e
y
e
a
r
o
f
t
h
e
p
h
o
t
o
g
r
a
p
h
s
a
s
s
h
o
w
n
a
n
d
w
e
r
e
o
u
t
s
i
d
e
o
f
t
h
e
u
n
v
e
g
e
t
a
t
e
d
c
h
a
n
n
e
l
i
n
a
l
l
p
r
e
v
i
o
u
s
y
e
a
r
s
.
Th
e
r
i
s
k
a
n
d
r
a
t
e
o
f
e
r
o
s
i
o
n
a
r
e
s
h
o
w
n
a
l
o
n
g
t
h
e
H
C
M
Z
B
o
u
n
d
a
r
y
.
T
i
m
e
-
l
a
p
s
e
C
a
m
e
r
a
3
,
w
h
i
c
h
w
a
s
a
t
M
P
6
.
7
,
w
a
s
p
o
i
n
t
e
d
l
o
o
k
i
n
g
u
p
s
t
r
e
a
m
a
t
t
h
e
ex
t
e
n
s
i
v
e
r
i
p
r
a
p
a
l
o
n
g
t
h
e
r
i
g
h
t
b
a
n
k
.
Cl
e
a
r
C
r
e
e
k
s
i
d
e
c
h
a
n
n
e
l
Ac
t
i
v
e
_
f
a
s
t
Ac
t
i
v
e
_
m
e
d
i
u
m
Ac
t
i
v
e
_
s
l
o
w
Hi
g
h
_
f
a
s
t
Hi
g
h
_
m
e
d
i
u
m
Hi
g
h
_
s
l
o
w
Lo
w
Ar
m
o
r
e
d
Mo
d
e
r
a
t
e
_
f
a
s
t
Mo
d
e
r
a
t
e
_
m
e
d
i
u
m
Mo
d
e
r
a
t
e
_
s
l
o
w
Ve
r
y
l
o
w
Ne
w
l
y
A
c
t
i
v
e
2
0
0
2
Ne
w
l
y
A
c
t
i
v
e
1
9
9
4
Re
a
c
h
B
o
u
n
d
a
r
i
e
s
Ne
w
l
y
A
c
t
i
v
e
1
9
8
1
Ne
w
l
y
A
c
t
i
v
e
1
9
7
7
Ne
w
l
y
A
c
t
i
v
e
1
9
7
1
Ne
w
l
y
A
c
t
i
v
e
1
9
6
0
Ne
w
l
y
A
c
t
i
v
e
1
9
5
0
Un
v
e
g
e
t
a
t
e
d
C
h
a
n
n
n
e
l
1
9
3
9
Riprap County
R
o
a
d
M
i
l
e
P
o
s
t
Jefferson
C
o
u
n
t
y
R
o
a
d
River
M
i
l
e
s
Constructed
L
o
g
J
a
m
s
Me
a
n
d
e
r
m
o
v
e
d
d
o
w
n
s
t
r
e
a
m
a
n
d
o
u
t
w
a
r
d
u
n
t
i
l
it
s
m
o
v
e
m
e
n
t
w
a
s
l
i
m
i
t
e
d
b
y
t
h
e
r
o
a
d
a
f
t
e
r
1
9
7
7
Meander
h
a
s
m
o
v
e
d
o
u
t
w
a
r
d
Pe
r
i
o
d
i
c
m
o
v
e
m
e
n
t
o
f
m
e
a
n
d
e
r
s
a
l
o
n
g
th
i
s
r
e
l
a
t
i
v
e
l
y
s
t
r
a
i
g
h
t
s
e
c
t
i
o
n
Me
a
n
d
e
r
m
o
v
e
m
e
n
t
i
s
l
i
m
i
t
e
d
b
y
t
h
e
C
o
u
n
t
y
Ro
a
d
a
n
d
t
h
e
v
a
l
l
e
y
e
d
g
e
Figure 47
Ae
r
i
a
l
p
h
o
t
o
g
r
a
p
h
t
a
k
e
n
J
u
l
y
2
0
0
2
2,
0
0
0
0
2
,
0
0
0
1,
0
0
0
Fe
e
t
Ti
m
e
-
l
a
p
s
e
C
a
m
e
r
a
3
Ar
e
a
o
f
a
c
t
i
v
e
e
r
o
s
i
o
n
a
l
o
n
g
m
e
a
n
d
e
r
b
e
n
d
Se
c
t
i
o
n
a
l
o
n
g
w
h
i
c
h
l
o
g
j
a
m
s
were
c
o
n
s
t
r
u
c
t
e
d
1
9
9
8
a
n
d
2
0
0
3