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City
Major Streams
Watershed Boundary
0
5
10
Miles
15
Current State
Channel Restoration Boundaries
Private Property Boundary
Historic (1942) Stream Channels
Current Stream Channels
0
0.125 0.25
0.5
0.75
1
Miles
Camp Hale
Benefits – large unique system, extensive
wetlands, fish habitat, food web support,
historical enhancement, education?
 Potential approaches

– Restore meandering form and floodplain
connectivity (~ 5 miles)
– Grade swath through valley floor
– Leave straight channel as floodplain remnant
– Re-establish vegetation…
Reference Reaches
“Mistakes are made when an apparently stable
reach is used as a template…Implicit in [this]
approach is the assumption that the river channel
has adjusted to the amount of water and sediment
supplied to it. A river requiring restoration is
unlikely to be in such as state precisely
because….water and sediment supply have
changed…”
From Wilcock (1997)
Channel Geometry Above Resolution Creek (146 cfs)
Hey & Thorne (0.03)
Yalin
tau* = 0.045
0.01 kg/s, 2.4 mg/l
0.014
Soar & Thorne (0.5, n)
Hey & Thorne (0.04)
tau* = 0.035
tau* = 0.05
0.1 kg/s, 24 mg/l
Soar & Thorne (0.5, k)
Hey & Thorne (0.05)
tau* = 0.04
0.001 kg/s, 0.24 mg/l
Soar & Thorne (a, n)
Slope (ft/ft)
0.012
0.010
0.008
0.006
0.004
0.002
12.5
15.0
17.5
20.0
22.5
25.0
Top Width (ft)
27.5
30.0
32.5
35.0
Channel Geometry-Below Resolution Creek (213 cfs)
Hey & Thorne (0.02)
Hey & Thorne (0.05)
Soar & Thorne (a, n)
Soar & Thorne (0.5, k)
tau* = 0.04
0.001 kg/s, 0.16 mg/l
Hey & Thorne (0.03)
Andrew (n)
Soar & Thorne (a, k)
Yalin
tau* = 0.045
0.01 kg/s, 1.6 mg/l
Hey & Thorne (0.04)
Andrews (k)
Soar & Thorne (0.5, n)
tau* = 0.035
tau* = 0.05
0.1 kg/s, 16 mg/l
0.012
Slope (ft/ft)
0.010
0.008
0.006
0.004
0.002
15.0
20.0
25.0
30.0
Top Width (ft)
35.0
40.0
45.0
River restoration - assisting the recovery
of ecological integrity in a degraded
watershed system by reestablishing
natural hydrologic, geomorphic, and
ecological processes, and replacing lost,
damaged, or compromised biological
elements
What is “natural” channel design?

Essentially lock in channel at desired
equilibrium width and depth and wait for
vegetation to “take over”
vs.
 Use soft bioengineering or regeneration and
attempt to place channel on “best”
trajectory toward desired state
Trade-offs

Relative costs
 Time-scale for self-organization /
equilibrium – e.g. Wolman & Gerson
 Lateral adjustment natural but can be
perceived as failure, may not achieve
habitat goals in desired time frame
 Uncertainty regarding conveyance, shear
partitioning, and sediment continuity?
Conclusions

Context / goal-specific
 Opportunity for engineers, geomorphologists,
aquatic and riparian ecologists to collaborate
 Implications for triage and setting priorities
– Full structural approach infeasible at scales needed
– Better understanding, channel evolution model and
recovery time scales could improve ecological
effectiveness of stream restoration
Questions

If flow and sediment delivery have been reduced through a
combination of climate change and reservoir influences, how
might you expect your design to differ from the historical
system?

How do you propose to modify the sine-generated wave
planform to make it look more natural? How does your
design planform relate to the historical pattern? Do you
propose to simply utilize the historic pattern?

The watershed stakeholders are very interested in improving
fish habitat in this segment. What are your recommendations
for enhancing fish habitat and how do these
recommendations potentially affect your design?

How should you refine the design by incorporating gradually
varied flow where S0 ≠ Sf? How would a gradually varied
flow analysis likely affect your design?
Questions



Briefly describe what steps you would take to reconnect the
channel with its historical floodplain and to facilitate the reestablishment of wetland plant communities and functions on
the valley floor.
Stream and wetland restoration activities at Camp Hale would
undoubtedly require a multifaceted regulatory review process
under NEPA and the Clean Water Act (specifically, a §404
permit). What is a §404 permit? Which federal agency issues
§404 permits? What are the two major types of §404 permits
and the key differences between the two? Which Nationwide
§404 Permits relate to stream restoration and monitoring?
Describe the major goals of NEPA in 2-3 sentences. What are
the three major possible outcomes in a NEPA process? Camp
Hale is on the National Register of Historic Places and issues
around §106 of the NHPA will be a major focus in the review
process. What key questions would be raised in accordance
with §106? Who is the SHPO and how would they be involved
in the NEPA process?
All points on curve satisfy continuity of water and sediment
a
Slope
MSP
Width
Stable Channel Design
Inputs
Equations
Design Q
Inflowing Qs
Grain Size Dist.
Valley Slope
General Geometric Form
Bank Roughness
Stable Bank Angle/Height
Continuity
Manning or Darcy-Weis.
Sediment Transport
Grain/Bed Roughness
Roughness Partitioning
Shear Stress Partitioning
Geometric Form
Width?
Outputs
Width?
Depth
Slope
Velocity
Sinuosity
Total, Bed, and Bank Rough.
Shear on Bed Avail. for Qs
Risk

What is the risk of having a 10 year flow in
the first 3 years after project completion?
Risk  1  1  p 
n
Risk  1  1  0.1
Risk  27.1%
3
Bankfull *
Hey and Thorne thick
Hey and Thorne thin
Charlton et al. thick
Charlton et al. thin
Width (m)
0.10
0.09
0.08
t*
τ*
0.07
0.06
0.05
0.04
0.03
1
2
3
Vegetation Type
4
Mean Values of Shields Parameter by Vegetation Type
type 1
type 4
(grassy
(>50% p-value
banks) tree/shrub)
thin
thick
p-value
Andrews (1984)
0.037
0.055
0.0005



Charlton et al. (1978)
0.035
0.063
0.0016



Hey and Thorne (1986)1
0.047
0.070
0.0028
0.045
0.078
0.007
1
thin = Hey and Thorne types 1 and 2, thick = Hey and Thorne types 3 and 4
Hey and Thorne type estimated from photographs
p-value = probability that * for thin vegetation is less than * for thick vegetation
2
Mean Values of the Shields Parameter Stratified by Bank Vegetation and
Channel Size. Differences in Shields parameter by vegetation type are
significant only for channels < 20 m wide
Channels with width < 20 m
thin
thick
p-value
Channels with width > 20 m
thin
thick
p-value
Andrews (1984)
0.034
0.058
0.0003
0.038
0.030
0.310
Charlton et al. (1978)
0.032
0.073
0.0040
0.038
0.047
0.397
Hey and Thorne (1986)
0.045
0.094
0.0002
0.048
0.050
0.849
p-value = probability that * for thin vegetation is less than * for thick vegetation in channels < 20 m,
and the probability that * for thin vegetation is different than * for thick vegetation in channel
widths > 20 m
Contours of Velocity (m/s)
Contours of Fluid Shear Stress (Pa)
1.5
bed/o
1.25
1
0.75
0.5
0.25
0
-10
-5
0
5
10
Distance from centerline (m)
W=20m, no veg
W=20m, veg
1.5
bed/o
1.25
1
0.75
0.5
0.25
0
-10
-5
0
5
10
Distance from centerline (m)
W=12m, no veg
W=12m, veg
1.5
bed/o
1.25
1
0.75
0.5
0.25
0
-10
-5
0
5
Distance from centerline (m)
W=6m, no veg
W=6m, veg
10
Vegetation Effects on
Geometry





W and τ* highly influenced by bank vegetation
Vegetation effects are scale-dependent
Thicker vegetation often yields deeper channels
with more pool habitat / lower temperatures
Bank vegetation influences the amount of shear
available to transport bed sediments
Shear “partitioning” effect of vegetation is less
significant for larger channels
Now we have a very interesting
and challenging design problem:

Where do I place design width on swoosh /
family of solutions (in light of scale
dependence, changes in vegetation and
accompanying changes in shear, roughness,
conveyance)?
 “Co-evolution”?
“Thick”
vegetation
“Thin”
vegetation
a
Slope
Minimum SP
Width