Chapel Slide Restoration -...

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Chapel Slide Restoration

2014 Post Run-off Monitoring Report

Chapel Slide Restoration Reach during the Spring Runoff of 2013

July 7, 2015

US Department of Agriculture Kootenai National Forest

Cabinet Ranger District

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Prepared By: Craig Neesvig District Hydrologist Cabinet R.D. – Trout Creek, MT TABLE OF CONTENTS 1.0 Introduction 1.1 Existing Condition – Prior to Restoration

1.2 Connected Downstream Instability

1.3 Project Design

1.4 Reference Reach Descriptive Information

1.5 Hydraulics and Sediment Transport 1.6 2012-2013 Restoration Activities 1.7 Riparian Revegetation

1.8 Timing, Duration and Permitting 1.9 Water Years 2013 and 2014 Runoff Monitoring 1.10 Dimension, Profile and Photo Monitoring 1.11 Project Channel Dimensions 1.12 Reference Channel Dimensions 1.13 Stream Channel Succession 1.14 Project Channel Profile 1.15 Reference Channel Profile 1.16 Substrate Monitoring – Project Reach 1.17 Substrate Monitoring – Reference Reach 1.18 Conclusions 1.19 References List of tables Table 1.1 – Existing Morphological variables at the Chapel Slide project site. Table 1.2 Summary of reference reach variables by site.

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Table 1.3 Summary of Design Dimensions. Table 1.4 Particle size distribution above the project site. Table 1.5 Equipment time and materials cost for the Vermilion River Chapel Slide reach restoration. Table 1.6 Planting, Irrigation and Maintenance Cost Summary for the Vermilion River Chapel Slide reach restoration. Table 1.7 Stream Channel Construction and Riparian Revegation Project Duration. Table 1.8 monitoring items for the Vermilion River Chapel Slide reach. Table 1.9 monitoring items for the Vermilion River Reference reach. Table 1.10 Summary of monitored project dimension reach variables 2012 – 2013 – 2014. Table 1.11 Summary of monitored reference dimension reach variables 2013 – 2014. Table 1.12 Comparison of Vermilion reference and Chapel Slide dimension reach variables 2013 – 2014. Table 1.13 Vermilion stream successional threshold values derived from reference reaches within the Cabinet and Libby Ranger Districts. Table 1.14 Dimensionless project reach variables 2012 – 2013 – 2014. Table 1.15 Summary of monitored pattern and profile As-built reach variables 2012 -2013 – 2014. Table 1.16 Summary of monitored pattern and profile reference reach variables 2013 – 2014. Table 1.17 Riffle and reach particle size distribution within the project reach. Table 1.18 Riffle and reach particle size distribution within the upstream reference reach. Table 1.19 Comparison of Vermilion reference and Chapel Slide substrate reach variables 2013 – 2014. List of Figures Figure 1.1 The Chapel Slide reach Vermilion River channel restoration project location.

Figure 1.2 Chapel Slide 2005.

Figure 1.3 Chapel Slide 2009.

Figure 1.4 Pre-restoration existing condition within the Chapel Slide reach of the Vermilion River. Figure 1.5 Chapel Slide representative cross section and associated shear stress values prior to restoration.

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Figure 1.6 Existing reference channel conditions above the Chapel Slide reach of the Vermilion River. Figure 1.7 Design planform of the Chapel Slide reach of the Vermilion River. Figure 1.8 Chapel Slide design cross section and associated shear stress values.

Figure 1.9 As-built channel within the Chapel Slide restoration reach of the Vermilion River one year post run-off. (Looking upstream from station 4+00). Figure 1.10. Temporary access road utilized for the Chapel Slide restoration. Figure 1.11. Temporary water diversion utilized for the Chapel Slide restoration. Figure 1.12. Materials stockpile at staging area and within the immediate project work site. Figure 1.13. Riparian vegetation in the Chapel Slide reach 1 month post planting. Figure 1.14. Riparian vegetation fenced enclosures at the base of the Chapel slide utilized on the recently constructed floodplain. Figure 1.15. Hydrograph of the Vermilion River for water year 2013. Figure 1.16. Hydrograph of the Vermilion River for water year 2014. Figure 1.17 Monitored post runoff riffle cross section #1 at station 0+56. Within the graphs the solid line represents the bankfull elevation. From top to bottom (clockwise) the pictures represent 2012, 2013 and 2014 cross section photos. Figure 1.18 Monitored post runoff riffle cross section #2 at station 1+11. Within the graphs the solid line represents the bankfull elevation. From top to bottom (clockwise) the pictures represent 2012, 2013 and 2014 cross section photos. Figure 1.19 Monitored post runoff riffle cross section #3 at station 1+22. Within the graphs the solid line represents the bankfull elevation. From top to bottom (clockwise) the pictures represent 2012, 2013 and 2014 cross section photos. Figure 1.20 Monitored post runoff riffle cross section #4 at station 1+85. Within the graphs the solid line represents the bankfull elevation. From top to bottom (clockwise) the pictures represent 2012, 2013 and 2014 cross section photos. Figure 1.21 Monitored post runoff riffle cross section #5 at station 2+71. Within the graphs the solid line represents the bankfull elevation. From top to bottom (clockwise) the pictures represent 2012, 2013 and 2014 cross section photos. Figure 1.22 Monitored post runoff riffle cross section #6 at station 3+09. Within the graphs the solid line represents the bankfull elevation. From top to bottom the pictures represent 2012, 2013 and 2014 cross section photos. Figure 1.23 Monitored post runoff riffle cross section #7 at station 3+15. Within the graphs the solid line represents the bankfull elevation. From top to bottom (clockwise) the pictures represent 2012, 2013 and 2014 cross section photos.

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Figure 1.24 Monitored post runoff riffle cross section #8 at station 3+69. Within the graphs the solid line represents the bankfull elevation. From top to bottom (clockwise) the pictures represent 2012, 2013 and 2014 cross section photos.

Figure 1.25 Monitored post runoff riffle cross section #1 at station 0+83.5. Within the graphs the solid line represents the bankfull elevation. The picture represents the 2014 cross section photo (looking downstream). Figure 1.26 Monitored post runoff riffle cross section #2 at station 1+77.8. Within the graphs the solid line represents the bankfull elevation. The picture represents the 2014 cross section photo (looking downstream). Figure 1.27 Monitored post runoff riffle cross section #3 at station 4+85. Within the graphs the solid line represents the bankfull elevation. The picture represents the 2014 cross section photo (looking upstream). Figure 1.28 Monitored post runoff riffle cross section #4 at station 5+47. Within the graphs the solid line represents the bankfull elevation. The picture represents the 2014 cross section photo (looking upstream).

Figure 1.29. Dimension variable percent change within the project and reference reach through 2013 and 2014.

Figure 1.30. Vermilion Project Reach longitudinal profile of 2013 and 2014. Figure 1.31. Vermilion Reference Reach longitudinal profile of 2013 and 2014. Figure 1.32. Substrate variable percent change within the project and reference reach through 2013 and 2014.

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1.0 Introduction The Vermilion River is a major tributary to the Lower Clark Fork River (see Figure 1.1) and lies in the Northwest corner of Montana. The Vermilion River is a perennial fourth order stream draining a watershed influenced by land uses including historic and ongoing placer mining as well as commercial forestry. The Vermilion River is one of only a few fourth order drainages in the Lower Clark basin that ensures perennial streamflows throughout the length of the mainstem.

The stream flow runoff regime, in particular spring runoff, is periodically influenced by rain-on-snow and rain on snowmelt events that can occur anytime during the winter months in response to warm air temperatures and rain. Typically, however the peak flow event occurs in May or early June.

Figure 1.1 The Chapel Slide reach Vermilion River channel restoration project location.

Montana’s 1996 303(d) list classified 22.5 miles of the Vermilion River as impaired and only partially supporting its beneficial uses of aquatic life and cold water fisheries. At this time sediment was listed as the pollutant of concern in the watershed. In 2005, the Lower Clark Fork River Drainage Habitat Problem Assessment ranked the Vermilion River as the highest priority for improving and protecting native fish habitat in the Lower Clark Fork drainage. In 2007, the District in cooperation with Avista and Montana Fish, Wildlife and Parks completed a watershed assessment that analyzed current geomorphic, vegetative, sediment and fisheries conditions and prioritized restoration projects in the Vermilion drainage with a focus on sediment reduction and improving populations of native bull trout and westslope cutthroat trout. This analysis and further reference sediment data collected in the Lower Clark Fork confirmed that fine sediment levels in the lower mainstem of the Vermilion River are currently above reference conditions and may be affecting native salmonid habitat.

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Figure 1.2 Chapel Slide 2005 Figure 1.3 Chapel Slide 2009

Within the assessment the highest priority site identified for restoration was the Chapel Slide, a large (300’ long, 140’ high) eroding mass waste that delivered approximately 712 tons per year of fine sediment (under average flood conditions) into a high priority Bull trout spawning area just below Vermilion Falls. Located approximately 0.75 miles below Vermilion Falls, this site was the single largest sediment contributor in the Vermilion drainage, accounting for over 80% of all sediment produced in Reach 6. This is of concern because although reach six is the most important bull trout spawning area in the Vermilion River, it has limited pool depth and frequency, poor substrate quality, and relatively little LWD. In addition, effects from these sediment inputs may currently be compromising downstream spawning habitat. In 2008, a year of above average runoff, approximately 7100 tons of sediment was produced. The river was actively eroding the toe of the slide and a vertical face approximately 65 feet high has developed that is extremely unstable and vulnerable to additional mass failure.

Numerous entities were involved from project initiation to project completion. Outside funding mechanisms included grants from Avista Utilities, Montana Fish Wildlife and Parks (MFWP) Future Fisheries Improvement Program, National Fish & Wildlife Foundation Bring Back the Natives, National Fish Habitat Action Plan, Sanders County RAC, and the Kootenai National Forest. The combination of funding sources allowed for this project to occur. Although the USFS Cabinet Ranger District took the lead on this project, deliverables would have not been attainable without the involvement and similar goals of these outside agencies. During the summer of 2012 employees from the Cabinet and Libby ranger districts initiated channel realignment and stream restoration activities within a portion of reach 6 of the Vermilion River. Approximately 500 feet of new channel was constructed over the course of three weeks. With the exception of the materials staging area, which was granted on adjacent Plum Creek Timber land, all portions of the project were on national forest land.

This report outlines trends through the first two years of runoff and will assess progress toward achieving restoration success as recommended in the Vermilion watershed assessment. Although this report summarizes the first 2 years post construction, monitoring will continue until final vegetative and in-channel success is attained.

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1.1 Existing Condition – Prior to Restoration Prior to the 1997 runoff season (which harbored one of the largest events in the period of record (roughly a 50 year flood event)), this area of the Vermilion River noticed sediment entrainment at a more subtle rate. The slide area, which to a lesser extent did exist at this time, was located on the right bank of a deep riffle that limited the amount of near-bank shear stress. This bank stress was thought to be similar to what would be expected in a reference location. It is thought that the 1997 event exacerbated the slide area when a log jam formed at the slide area and fashioned a temporary vortex that increased local shear stress at the toe of the slide. At this time the main river channel had migrated to the base of the hillside. The hillside mostly composed of homogenous sand and fine gravel began to destabilize and, through a series of rotational hillslope failures, allowed the channel to laterally migrate into the slide roughly75 feet.

Figure 1.4 Pre-restoration existing conditions within the Chapel Slide reach of the Vermilion River

Prior to destabilization the Vermilion River in this area supported a multi-aged riparian community including serviceberry, Sitka Alder, black cottonwood, and various conifers. The channel above the project reach exists as a confined Rosgen type B3 channel with average width/depth ratios being noticed that currently transport sediment efficiently. Before restoration the project site existed as an overwidened channel with high width to depth ratios. The banks throughout this area are composed of mostly gravel and sand with limited amounts of cobble. The natural channel slope within the project reach was roughly 2 % before restoration.

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Table 1.1 – Existing Morphological variables at the Chapel Slide project site.

XS# Bankfull Width

Floodprone Width

Entrenchment Ratio

Mean Depth

Maximum Depth

Width/Depth Ratio

Bankfull Area

Water Surface Slope

1 43.78 100.12 2.29 3.25 4.39 13.47 142.23 0.023

2 62.28 156.64 2.51 2.36 3.22 26.39 147.12 0.023

3 59.02 113.22 1.92 2.39 4.02 24.69 141.2 0.023

Mean 55.03 123.33 2.24 2.67 3.88 21.52 143.52 0.023

Figure 1.5 Chapel Slide representative cross section and associated shear stress values prior to restoration

The riparian corridor remained intact until reaching the project site where the exposed mass waste on the right bank supplied constant fine sediment under all flow conditions. Prior to the 2012 restoration, this area of the Vermilion had transitioned more toward a overwidened “C” type Rosgen system rather than the original “B” or “Bc” transport type channel that it historically was. This channel evolution led to the increase in shear stress at the toe of the slide and subsequent continual mass wasting.

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The fish habitat complexity consisted of an overwidened riffle and minimal, functional in-channel Large Woody Debris (LWD). The 1996 event, along with the over-bankfull type flooding that occurred during the spring of 2008, is thought to have been the major contributors to the degraded condition of this reach.

1.2 Connected Downstream Instability Shortly downstream of the Chapel Slide area, effects from historic mining can be noticed within the mainstem. The Miners Gulch reach has experienced a level of sediment deposition directly related to the unraveling of the Chapel slide. Numerous field investigations and time series air photo analysis have confirmed that the majority of sediment produced from the Chapel Slide during water years 1997-2011 has been transported downstream through the 1.5 miles of higher gradient channel and deposited directly to the Miners Gulch area below, the next area of restoration focus. This connected downstream area aided in project design.

1.3 Project Design The mass waste that existed directly adjacent to this channel was actively contributing fine sediment downstream to Miners Gulch. The size and progression of the wasting hillside drove alternative development and led to the total stream channel realignment and restoration. The action alternative that was selected involved temporarily diverting water at an upstream location from the current channel to one of the two other braids (in the more central floodplain away from slide area) while restoring the reactivated channel as a single thread channel in a similar location to where it existed prior to 1997. Along with in-channel LWD structures and grade control to maintain the constructed energy dissipating pools, a floodplain bankfull bench was built were the current unstable channel was located. An approximate 1000 foot section of full bench temporary road was constructed to access the site with equipment. Upon project completion this access road was decommissioned with a full recontour type approach. Chapel Slide Restoration Activity Summary

- Access- Constructed approximately ¼ mile of temporary road, Decommissioned after channel work was completed.

- Restoration method- Relocated stream to a historic channel away from the toe of the slide, plugged unstable channel near toe, and restored new channel and floodplain dimensions.

- Structure types used- Bankfull bench, rootwad revetments, debris jams, random boulder placement and cobble patches for grade control.

- Restoration length- Approximately 500 feet of channel restoration. - In-channel project duration- Approximately 15 days. - Channel diversion- work would be accomplished using a clear-water diversion around the work

site through the majority of the project. - Revegetation- Disturbed areas as well as newly built floodplain was planted with native species

including cottonwood, conifers and miscellaneous shrubs.

1.4 Reference Reach Descriptive Information Information was gathered in similar channels with reference reach characteristics, or channel reaches with dimensions, slopes and profiles that seem to be naturally providing for long-term stability. The main reference reach utilized for the Chapel Slide project design was located directly upstream. Applicable reference reach data was compiled from a few other nearby locations and provided for a range of options. All of these reaches displayed similar channel types and substrate, as well as local slope, flow regime and bankfull characteristics. The riparian corridor within these reference locations is what is

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believed the project site was like prior to the vegetation alteration and channel changing events. The table below (Table 1.2) displays the reference reach variables by site.

Table 1.2 Summary of reference reach variables by site

Reference Variables Vermilion River B3 Channel type

West Fork Trout Creek C4 Channel Type

East Fork Bull River B3c Channel type

Drainage Area (sq. miles) 49.92 19.5 26.05 Bankfull Area (Riffle) 130 91.54 45.59 Bankfull Q 585 280 228 Width/Depth (Riffle) 17.5 19.85 15.37 Entrenchment Ratio 1.18 4.69 5.67 Bankfull Width (Riffle) 47.55 42.68 26.44 Bankfull Mean Depth (Riffle) 2.72 2.15 1.72 Bankfull Max Depth (Riffle) 4.18 3.5 2.41 Bankfull Max Depth (Run) 3.2 4.2 3.8 Bankfull Max Depth (Pool) 6.5 5.6 4.6 Bankfull Max Depth (Glide) 4.6 3.2 4.1 Average Riffle Slope .023 .012 - .018 .02 Average Run Slope .125 .529 .09 Average Pool Slope .02 .016 .007 Average Glide Slope .067 .030 .12 Run length (RL) 17-25 15-30 6-25 Glide length (GL) 13-25 12-30 15-55 Total Pool Length (RL+GL+PL)

15-40 20-75 18-60

Figure 1.6 Existing reference channel conditions above the Chapel Slide reach of the Vermilion River

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Existing and Design Longitudinal Profile, Channel Dimensions

The constructed project included more pool habitat and has provided for a more stable grade that will maintain the long term stability within this section of the Vermilion River. Proposed channel design characteristics such as Bankfull area (BFA), Bankfull width (BFW), Bankfull mean depth (BFDMN), Bankfull maximum depth (BFDMX) Bankfull discharge (BFQ), and Bankfull mean velocity (BFU) have been calculated for the design constructed riffle, run, pool, and glides within the project reach (see table 1.3). Design depths have taken reference reach information into account as well as local scour depth calculation at the flume locations (run locations). The calculated scour depths have taken variables such as sediment density, particle size, discharge at bankfull, gravitational acceleration, water density, run slope, run width, and fall height into account. Maximum scour depths at the run locations were approaching 6 feet in the project area under a bankfull type (1.5 yr.) flood event. These calculations have provided additional insight into how, and at what elevation footer rock and logs will be installed to ensure long-term stability.

Table 1.3 Summary of Design Dimensions

Dimension Variables Pre-Project Riffle (C3)

Design Riffle Design Run Design Pool Design Glide

Drainage Area (sq. miles) 53.93 53.93 53.93 53.93 53.93 BFA 141 143 113 250 225 BFQ (cfs) 675 675 675 675 675

BFU (fps) 4.50 4.5 6 2.7 3.0

Width/Depth (Riffle) 26.04 24 19 15.0 22

Entrenchment Ratio 2.63 4.16 5.26 3.45 3.33

BFW (Riffle) 62.49 55 48 58.2 60

BFDMN (Riffle) 2.4 2.6 2.10 3.40 2.67

BFDMX (Riffle) 3.27 4.2 3.35 6.50 3.58

Average Slope .018 -.02 .02 - .024 .09 - .14 .007 - .016 .030 - .12

Figure 1.7 Design planform of the Chapel Slide reach of the Vermilion River

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Figure 1.8 Chapel Slide design cross section and associated shear stress values By design the floodplain construction near the toe of the slide reduced the near bank shear stress. By moving the active channel away from the slide and constructing a floodplain bench at the bankfull elevation, water velocities and associated bank stress were drastically reduced. This floodplain bench was also constructed to accept future rotational failures from the slide as the slope works toward a stable angle of repose. To date the slide has re-slid twice onto the floodplain and has not intercepted the active channel as in years prior to construction.

1.5 Hydraulics and Sediment Transport Two different entrainment calculations were evaluated using the pebble count data that was taken just above the project site (see Table 1.2). Both calculations determined the critical shear stress at a riffle during a bankfull type flood event (1.5 yr flood). The first method uses the D50 size particle of a representative pebble count, the largest particle size found on a local channel bar, the bankfull mean depth and the average slope of the riffle (Rosgen Level III field manual, 2004). The second method uses the gravitational acceleration, hydraulic radius and average slope of the riffle, and the density of water (Gordon, 1992). The entrainment results for the first equation showed particles up to the D95 size where mobile under bankfull type flows. The results for the second equation were a little more conservative and yielded particle movement up the D84 size particle during a bankfull event. Both results provided valuable

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input into the design as far as the current movement of bedload through the project site directly downstream. Based on these results the cobble patch pool tail controls utilized the more conservative method and were constructed using a D95 size cobble/boulder matrix (~ 650 - 800 mm). The table below displays the particle size distribution used within the entrainment calculations (the riffle particle size distribution just above the project area).

Table 1.4 Particle size distribution above the project site

Cumulative % and Finer Particle Size (mm) Riffle

D16 20 D50 87 D84 267 D95 804

Silt / Clay (<.062 mm) 0 %

Sand (.062 – 2.0 mm) 2 %

Gravel (2.0 – 64 mm) 38 %

Cobble (64 – 256 mm) 44 %

Boulder (256 – 2048 mm) 16 %

Bedrock (> 2048 mm) 0 %

1.6 2012-2013 Restoration Activities During the month of August in 2012 approximately 500 feet of new channel was constructed through the depositional area of the local floodplain approximately 60 feet away from the toe of the slide. The historic channel location was converted back to an overbank floodplain area as what existed prior to the 1996 flood events. This restoration project created a new stream channel by utilizing upstream reference reach variables with the appropriate dimension, pattern, and profile for its specific location within the watershed.

Figure 1.9 As-built channel within the Chapel Slide restoration reach of the Vermilion River one year post run-off. (Looking upstream from station 4+00).

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A roughly ¼ mile stretch of roadway was built to accommodate equipment access as well as a conduit for delivering materials. This road was constructed on side slopes that exceeded 80%.

Figure 1.10. Temporary access road utilized for the Chapel Slide restoration.

Although a permit for short-term turbidity in the Vermilion River was obtained, a temporary water diversion, located in the unstable channel at the base of the slide, routed the majority of water around the work site to limit the amount of construction related sediment increases. Culverts were installed at one location to allow for equipment access.

Figure 1.11. Temporary water diversion utilized for the Chapel Slide restoration.

The new channel contains in-stream cobble/boulder near bank margin habitat as well as large wood to add complexity to the constructed stream channel. This placed material also provides for grade control and pool tail stabilization. All structures incorporated the final channel shaping to appropriate channel dimensions which were based on applicable local reference data. These techniques helped to protect

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adjacent banks by reducing localized shear stress and positioning the thalweg in a more natural location within the reach. The constructed channel pattern was designed to allow the river to utilize as much of the valley bottom as thought feasible. By constructing a wider floodplain area for this portion of the Vermilion it was foreseen that this technique would allow for more riparian vegetation to become established as well as aid in sediment and debris transport.

A total of 100 trees with attached rootballs were utilized within this project. Approximately 250 cubic yards (CY) of large angular rock was used for ballast or footer structure. Round cobble and boulder rock was imported to the site and used for grade control and habitat feature creation. As well as the imported materials, on-site resources such as the in-channel alluvium helped in the development of the new floodplain.

Figure 1.12. Materials stockpile at staging area and within the immediate project work site.

Table 1.5 Equipment time and materials cost for the Vermilion River Chapel Slide reach restoration

Item Unit Quantity Unit Price Total

Fully operated excavator w/ thumb (2 machines)

Hrs. 251.1 $130.00 $32,643

Fully operated excavator 314 CAT (1machine) Hrs. 53.2 $95.00 $5,054

Fully operated 10-12 CY Dump truck Hrs. 58.5 $80.00 $4,680

Fully operated Skidder Hrs. 34.3 $95.00 $3,259

Fully operated 3-5 CY Loader Hrs. 34.5 $105.00 $3,623

Fully operated D5 Dozer Hrs. 47.5 $100.00 $4,750

3X4X4 Assorted Angular Rock (delivered) Cubic Yards 250 $35.00 $8,750

3X4X4 Assorted Round Rock (delivered) Cubic Yards 250 $72.00 $18,000

50 ft long, 18-24” diameter sound log w/ 6-10’attached rootball (delivered)

Logs 100 $185.00 $18,500

16-24” sorted cobble (delivered) Cubic Yards 360 $68.00 $24,480

Mobilization EA 1 $5,600.00 $5,600

Rock Blasting EA 1 $3,789.00 $3,789

Water Diversion Culverts EA 1 $500.00 $500

Total $133,628

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1.7 Riparian Revegetation During the spring and fall of 2013 stream banks through the reach were further stabilized using native seed mixes, bare root seedlings, and live vegetation stakes. Floodplain plantings consisted of Black Cottonwood, Douglas Fir, Ponderosa Pine, Woods Rose, Serviceberry, Lewis’ Mockorange, Thinleaf Alder, and Sandbar Willow. All disturbed areas were seeded in the fall of 2012 shortly after construction with a cover crop of Annual Rye (Lolium rigidum) and Sitka Alder (Alnus sinuata). Local topsoil was imported from adjacent floodplain areas to the site and mixed directly with the coarse alluvium at each individual planting site. To protect the vegetation from browse a fenced riparian buffer was established in strategic locations during the revegetation effort of 2013.To protect the plants from drought an extensive irrigation system was installed during the summer of 2013.

Figure 1.13. Riparian vegetation in the Chapel Slide reach 1 month post planting

Planting

Fast growing tree species were desired on this site to build deep, extensive root systems and provide future large woody debris. A diversity of species were planted in hopes to increase the chances of adequate survival. Spacing was dense to compensate for expected high mortality. Natural seedlings, particularly cottonwood, were expected to colonize the site from adjacent seed sources and in the future will be encouraged and protected as necessary.

Much of the stream bank was not suitable for planting willow due to the height (2’) above base flow level. Although willow was planted where suitable conditions existed.

Shrub species suitable for the drier site conditions were planted along the stream bank. These plantings were augmented with direct seeding of native shrub species in fall 2013. Species un-palatable to ungulates were favored.

A native grass seed mix was sown in fall 2012 to provide shallow soil stability and begin building organic matter. Additional seed was also used in 2013.

Forest soil was collected and used in planting holes where necessary to provide additional nutrients, water holding capacity and biological associates that are beneficial to planted stock.

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Planting Materials List

Black Cottonwood- 100 3’-4’ bareroot trees on 12’x12’ spacing Planting Labor- 6 days

Conifer mix- 100+ total, inter-planted with cottonwood Planting Labor- 2 days

25 Douglas Fir

25 Ponderosa Pine

25+ Western Larch

25+ White Pine

Upland shrub seedlings- 100 Woods rose Planting Labor – 3 days

100 Serviceberry

100 Lewis’ Mockorange

100 Snowberry

Willow mix (Streambank, Sitka, Bebb, etc.) – up to 1400 2’ cuttings Planting Labor- 4 days

Shrub seed Lewis’ Mockorange (331,250 seeds/oz.) Labor (seeding) - .5 days

Snowberry (4687 seeds/oz.)

Kootenai dry site and productive site native grass mixes

Fencing

Protection from browsing was needed for Cottonwoods and ponderosa pine. Individual cages were considered most cost effective for the planting spacing and required less maintenance. Some browsing may occur when planting stock emerges from the top of 5’cages but they should grow above browsing height the subsequent year. The need for additional protection at the 5’ height will be assessed when trees reach that point.

Figure 1.14. Riparian vegetation fenced enclosures at the base of the Chapel slide utilized on the constructed floodplain.

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Fencing Materials List

Cages: 125 cages x 6.25’ per cage = 781.25’ of 2”x4”x60” fence – 8 rolls

2 6’ steel T-posts/cage = 250 posts

500 fence clips

Exclosure: 3 rolls fence

50 6’ T-posts

150 fence clips Fencing Labor – 12 days

Irrigation

Irrigation was considered critical to the survival of the plantings on this well drained site. A starting point watering target of 1” of water (approximately 8103 gal over 13,000ft

2) per week was used. Approximately

2 hours of pump run-time was needed to apply this quantity of water. Various gravity fed and drip systems were considered but due to the coarse soil texture little lateral spread of moisture from emitters was expected. To provide water to directly seeded species as well as encourage natural seedling establishment, a sprinkler system was required to distribute the water over the entire planting area. Sampling cups were used to ensure adequate water was applied at each watering.

Equipment: pump and accessories

750’ 1 ½” fire hose and fittings

14 sprinkler head assemblies Watering Labor (2013) - 11 days

Transporting materials to site

A combination of hand carrying, sled dragging and a rope zip-line were used to move materials down to the worksite. Zipline loads were attached to a large pulley and lowered on a 300’ tensioned line.

Labor- 6 days

Weed Control

Weeds have and will be controlled with wick (sponge) applied herbicide. Herbicide used will depend on weed species encountered. Applications will be made twice a year until trees and shrubs dominate the site.

Maintenance

2013-2014 watering 1 day/wk for 10 wks 10days/year

2014-2018+ fence adjustments and repair 3 days/year

2014-2018+ weed control 2 days/year

2014-2018+ replanting as needed 2 days/year

2018+ fence removal from shrub and ponderosa pine 6 days

Planning Labor- 5 days

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Table 1.6 Planting, Irrigation and Maintenance Cost Summary for the Vermilion River Chapel Slide reach restoration

Item Unit Quantity Unit Price Total

Planting Stock EA 1 $1,349.25 $1,349

Hardware and Tools EA 1 $9,792.87 $9,793

Labor (2013 and 2014) Days 59.5 $130.00 $7,735

Total $18,877

1.8 Timing, Duration and Permitting The timing of ground disturbing activities had to occur outside of the fish spawning in the Vermilion River as well as outside of high water conditions. In cooperation with Montana Fish Wildlife and parks a 124 permit was obtained with these timing restrictions set in place. Generally areas within the Lower Clark Fork notice low enough flow conditions and non-spawning windows between July 15

th and September 1

st.

It took a total of 38 days between 2012 and 2013 to complete the proposed activities. Other permits such as the Corp of Engineer Nationwide 404 permit were obtained with an additional 410 wetland certification that needed completion prior to any ground disturbing activities. An application packet with all existing and proposed channel locations as well as requested design variables was submitted for review early in the spring of 2010. Project activities began shortly after the acquisition of the 404/410 permits on July 15, 2012.

Table 1.7 Stream Channel Construction and Riparian Revegetation Project Duration

Temporary road construction 7/15 – 7/19 4 days

In-channel stream restoration 7/31 – 8/21 15 days

Road Obliteration 8/22 – 8/26 4 days

Riparian planting and Irrigation 5/28 – 6/21 15 days

TOTAL 38 days

1.9 Water Years 2013 and 2014 Runoff Monitoring A USFS stream gaging station exists roughly 9 miles below the project reach towards the mouth of the Vermilion River. The water years of 2013 and 2014 have been represented from the calibration of discrete manual measurements and automated 30 minute data. The hydrographs are displayed below (Figures 1.15, 1.16). In 2013 and 2014 most streams in northwestern Montana experienced average runoff with the Vermilion being no exception (USFS Cabinet Ranger District 2013, USFS Cabinet Ranger District 2014). Water Year 2013 A slight spike in flow was noticed in the beginning of December 2012 that was directly linked to a mild rain event. Other peak events were captured later in the year and the hydrograph displayed flows sustaining a bankfull discharge (Q1.5) of 1114 cfs for several days in May of 2013.

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Figure 1.15. Hydrograph of the Vermilion River for water year 2013.

Water Year 2014 A high intensity rain on snow event occurred in the beginning of March 2014. Peakflows related to this event surpassed the bankfull discharge for approximately 5 days. The peak flow of 2014 was 1,280 cfs, which equates to the approximate 2.1 year return interval flow (Q2.1). Other multiple events were captured later in the month of May 2014 and flows during this time approached but did not reach the bankfull discharge (Q1.5) of 1114 cfs.

Figure 1.16. Hydrograph of the Vermilion River for water year 2014.

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1.10 Dimension, Profile, Substrate and Photo Monitoring Upon completion of the construction activities in the late summer of 2012, as-built channel dimensions and profiles were surveyed within the project reach. In 2013 and 2014 this monitoring was repeated in the previous years monumented locations as well as the upstream reference reach. Photo points were also established at all monitoring sites through all survey efforts and reaches.

Table 1.8 monitoring items for the Vermilion River Chapel Slide reach

Monitoring Item Quantity

Channel Cross Sections (Harrelson et al., 1994)

8 ( 3 riffles, 3 pools, 2 glides)

Channel Longitudinal Profile (Harrelson et al., 1994)

1 ( the entire length of the project reach, approx. 500 ft.)

Wolman Pebble Counts (Harrelson et al., 1994)

4 ( 3 riffles, 1 reach)

Photo Points 17 (upstream and downstream of each monitored

cross section and 1 pre and post construction photos)

Table 1.9 monitoring items for the Vermilion River Reference reach

Monitoring Item Quantity

Channel Cross Sections (Harrelson et al., 1994)

4 ( 2 riffles, 2 pools)

Channel Longitudinal Profile (Harrelson et al., 1994)

1 ( the entire length of the project reach, approx. 600 ft.)

Wolman Pebble Counts (Harrelson et al., 1994)

3 ( 2 riffles, 1 reach)

Photo Points 17 (upstream and downstream of each monitored

cross section and 1 pre and post construction photos)

1.11 Project Channel Dimensions Eight channel cross-sections were measured and monumented within the project reach according to methods described by Harrelson et al. 1994. To establish a range of values for each feature and encompass the majority of the project area dimensions, representative riffle, run, pool and glide units were measured immediately after project completion and two following years post run-off (2012-2014). These results are displayed below in table 2.0 and the following graphs. Changes in the mean dimension reach variables of the project ranged from 4 to 18 percent in the first two runoff seasons. This magnitude of adjustment was expected and no transition towards an unstable channel type was occurring. A few of the monitored cross sections displayed slight aggradation while

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others displayed deepening of the channel from 2012 to 2014. For example the maximum depth in cross section 5 increased from 7.87 to 8.77 feet while maintaining stable channel banks and downstream grade control. The percent change in dimension variables decreased by roughly half in the 2014 season from that noticed during the initial first runoff season of 2013 (Table 2.0). This was expected, as the first season of runoff through a newly constructed channel may have a slight adjustment period related to the settling and sealing of the grade control and bank stabilization structures.

Table 1.10 Summary of monitored project dimension reach variables 2012 – 2013 - 2014

Dimension Variables Riffle XS#1

Pool XS#2

Glide XS#3

Riffle XS#4

Pool XS#5

Glide XS#6

Riffle XS#7

Pool XS#8

Mean Reach

BFA (2012 As-Built) 136.5 230.5 174.3 141.4 250.8 198.1 147.9 253.1

BFA (2013) 145.8 202.3 194.1 164.4 242.5 196.8 164.7 252.8

BFA (2014) 159.6 217.5 204.4 169.2 241.7 196.2 163.7 251.1

% Change in BFA (2012-2013) 6 14 10 14 3 1 10 0 7 % Change in BFA (2013-2014) 9 7 5 3 0 0 1 1 3 Width/Depth (2012 As-Built) 26.69 16.66 20.55 29.8 22.23 27.57 26.74 21.41 Width/Depth (2013) 25.10 18.47 18.28 24.28 18.81 23.56 24.20 21.98 Width/Depth (2014) 23.42 17.66 17.16 25.04 21.65 28.13 24.64 22.14

% Change in W/D (2012-2013) 6 10 12 23 18 17 10 3 12 % Change in W/D (2013-2014) 7 5 7 3 13 16 2 1 7 Entrenchment (2012 As-Built) 2.44 2.42 2.83 2.31 2.01 2.61 2.33 2.04 Entrenchment (2013) 2.49 2.45 2.52 2.35 2.16 2.05 2.21 2.00 Entrenchment (2014) 2.45 2.42 2.53 2.30 2.08 2.06 2.38 2.01

% Change in ER (2012-2013) 2 1 11 2 7 21 5 2 7 % Change in ER (2013-2014) 2 1 0 2 4 0 8 0 2 BFW (2012 As-Built) 60.31 61.96 59.8 64.97 74.68 73.9 62.85 73.65 BFW (2013) 60.48 61.13 59.6 63.12 67.52 68.1 63.17 74.51 BFW (2014) 61.13 61.97 59.2 65.10 72.30 74.3 63.56 74.60

% Change in BFW (2012-2013) 0 1 0 3 11 9 1 1 3 % Change in BFW (2013-2014) 1 1 1 3 7 8 1 0 3 BFDMN (2012 As-Built) 2.26 3.72 2.91 2.18 3.36 2.68 2.35 3.44 BFDMN (2013) 2.41 3.31 3.26 2.60 3.59 2.89 2.61 3.39 BFDMN (2014) 2.61 3.51 3.45 2.60 3.34 2.64 2.58 3.37

% Change in BFDMN (2012-2013) 6 12 11 16 6 7 10 1 9 % Change in BFDMN (2013-2014) 8 6 6 0 7 9 1 1 5 BFDMX (2012 As-Built) 3.51 6.60 4.46 3.86 7.87 4.46 3.70 6.52

BFDMX (2013) 3.92 4.60 5.65 4.37 8.53 5.06 4.91 5.94

BFDMX (2014) 3.95 5.08 5.78 4.60 8.77 4.81 4.87 6.19

% Change in BFDMX (2012-2013) 10 43 21 12 8 12 25 10 18

% Change in BFDMX (2013-2014) 1 9 2 5 3 5 1 4 4

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25


26


27


28


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Figure 1.22 Monitored post runoff riffle cross section #6 at station 3+09. Within the graphs the solid line represents the bankfull elevation. From top to bottom the pictures represent 2012, 2013 and 2014 cross section photos.

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31


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1.12 Reference Channel Dimensions Four channel cross-sections were measured during the same time period within the reference reach upstream of the project site. To establish a range of values for specific features and encompass the majority of the project area dimensions, representative riffle, and pool units were measured in the 2014 runoff season. These results are displayed below in table 2.1 and the following graphs. Changes in the mean dimension reach variables of the reference reach ranged from 1 to 6 percent through the 2014 runoff season. This is slightly lower than what was monitored in the project reach (2 to 7 percent), but fairly similar. The magnitude of adjustment was monitored to capture the natural changes within the reference reach directly upstream of the project site. Throughout this time period there was no transition towards an unstable channel type within the reference reach. A few of the monitored cross sections displayed slight aggradation while others displayed deepening of the channel from 2013 to 2014. The riffles within the reach saw minimal change within all dimension variables. The mean and maximum depths changed slightly within the pools. This reach maintained resilient bank and bed dimensions through this runoff cycle which briefly provided for bankfull flows (Q1.5).

Table 1.11 Summary of monitored reference dimension reach variables 2013 - 2014

Dimension Variables Pool XS#1 Riffle XS#2 Pool XS#3 Riffle XS#4 Mean Reach

BFA (2013) 140.1 141.6 198.7 148.1

BFA (2014) 137.2 142.2 200.1 148.7

% Change in BFA (2013-2014) 2 0 1 0 1 Width/Depth (2013) 19.76 39.96 18.05 14.10 Width/Depth (2014) 18.81 39.43 15.08 14.10

% Change in W/D (2013-2014) 5 1 16 0 6 Entrenchment (2013) 1.05 2.00 2.50 3.28 Entrenchment (2014) 1.09 2.00 2.73 3.27

% Change in ER (2013-2014) 4 0 9 0 3 BFW (2013) 52.57 75.12 59.9 45.68 BFW (2014) 50.79 74.91 54.9 45.82

% Change in BFW (2013-2014) 3 0 8 0 3 BFDMN (2013) 2.7 1.88 3.32 3.24 BFDMN (2014) 2.7 1.90 3.64 3.25

% Change in BFDMN (2013-2014) 0 1 10 0 3 BFDMX (2013) 5.29 3.95 6.44 4.36

BFDMX (2014) 5.40 3.96 6.55 4.40

% Change in BFDMX (2013-2014) 2 0 2 1 1

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Figure 1.25 Monitored post runoff riffle cross section #1 at station 0+83.5. Within the

graphs the solid line represents the bankfull elevation. The picture represents the 2014 cross section photo (looking downstream).

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Figure 1.26 Monitored post runoff riffle cross section #2 at station 1+77.8. Within the graphs the solid line represents the bankfull elevation. The picture represents the 2014 cross section photo (looking downstream).

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Figure 1.27 Monitored post runoff riffle cross section #3 at station 4+85. Within the graphs the solid line represents the bankfull elevation. The picture represents the 2014 cross section photo (looking upstream).

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Figure 1.28 Monitored post runoff riffle cross section #4 at station 5+47. Within the graphs the solid line represents the bankfull elevation. The picture represents the 2014 cross section photo (looking upstream).

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Table 1.12 Comparison of Vermilion reference and Chapel Slide dimension reach variables 2013 - 2014

Dimension Variables Mean Reach - Vermilion Reference (2013-2014)

Mean Reach – Chapel Slide Restoration (2013-2014)

% Change in BFA 1 3

% Change in W/D 6 7

% Change in Entrenchment 3 3

% Change in BFW 3 3

% Change in BFDMN 3 5

% Change in BFDMX 1 4

Figure 1.29. Dimension variable percent change within the project and reference reach through 2013 and 2014.

To a certain degree natural channel fluctuations are expected within most fluvial systems. The drainages in the Lower Clark Fork are no exception. Within stable channels major shifts in channel dimension variables generally occur during low frequency high intensity flood events. These can happen at any time but are largely related to Rain On Snow (ROS) events in this area of Northwest Montana. Monitoring throughout the Lower Clark Fork region suggests flood frequencies above 10 year return interval flows could exacerbate stream channels with good stability and most likely those displaying poor stability. In general terms dimension variables that drastically change under average runoff years or bankfull type flows point to severe instability or unnatural stream channel succession. Based on the differences between the percent change within the reference and project reach, the small fluctuations in dimension variables noticed are considered acceptable. As expected the changes in reference reach dimension variables are slightly less than the project reach. This could be related to a combination of things, such as a more imbricated well developed channel and/or a more established riparian component. Over time the project reach dimension fluctuations should closer relate to those of the reference reach directly upstream.

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1.13 Stream Channel Succession

Reference reach information similar to that obtained for the project reach has been collected from the Cabinet and Libby Ranger Districts since 1998. Dimensionless mean values have been stratified by stream type and threshold values where channel succession is most likely to occur have been developed. The Chapel Slide restoration reach has Rosgen “B/C” channel types as the desired design type. The local reference derived threshold values surrounding the possible morphological changes in a “C” channel type are represented below in Table 2.2.

Table 1.13 Vermilion stream successional threshold values derived from reference reaches within the Cabinet and Libby Ranger Districts.

Dimension Variables C to B C to G C to F C to D

Dimensionless W/D > 1.31 < 0.54 > 1.47 > 6.76

Dimensionless Entrenchment < 0.43 < 0.56 < 0.32 < 0.72

Dimensionless BFW/BFDMN > 1.37 < 0.57 > 1.71 > 7.26

Dimensionless BFW/BFDMX > 1.23 < 0.61 > 1.40 > 3.72

Table 1.14 Dimensionless project reach variables 2012 – 2013 - 2014

Dimension Variables Riffle XS#1

Pool XS#2

Glide XS#3

Riffle XS#4

Pool XS#5

Glide XS#6

Riffle XS#7

Pool XS#8

Mean Reach

Width/Depth (2012 As-Built) 26.69 16.66 20.55 29.8 22.23 27.57 26.74 21.41

Width/Depth (2013) 25.1 18.47 18.28 24.28 18.81 23.56 24.2 21.98

Width/Depth (2014) 23.42 17.66 17.16 25.04 21.65 28.13 24.64 22.14

Dimensionless W/D (2012-2013) 0.94 1.11 0.89 0.81 0.85 0.85 0.91 1.03 0.92

Dimensionless W/D (2013-2014) 0.93 0.96 0.94 1.03 1.15 1.19 1.02 1.01 1.03

Entrenchment (2012 As-Built) 2.44 2.42 2.83 2.31 2.01 2.61 2.33 2.04

Entrenchment (2013) 2.49 2.45 2.52 2.35 2.16 2.05 2.21 2

Entrenchment (2014) 2.45 2.42 2.53 2.3 2.08 2.06 2.38 2.01

Dimensionless ER (2012-2013) 1.02 1.01 0.89 1.02 1.07 0.79 0.95 0.98 0.97

Dimensionless ER (2013-2014) 0.98 0.99 1.00 0.98 0.96 1.00 1.08 1.01 1.00

BFW (2012 As-Built) 60.31 61.96 59.8 64.97 74.68 73.9 62.85 73.65

BFW (2013) 60.48 61.13 59.6 63.12 67.52 68.1 63.17 74.51

BFW (2014) 61.13 61.97 59.2 65.1 72.3 74.3 63.56 74.6

Dimensionless BFW (2012-2013) 1.00 0.99 1.00 0.97 0.90 0.92 1.01 1.01 0.98

Dimensionless BFW (2013-2014) 1.01 1.01 0.99 1.03 1.07 1.09 1.01 1.00 1.03

BFDMN (2012 As-Built) 2.26 3.72 2.91 2.18 3.36 2.68 2.35 3.44

BFDMN (2013) 2.41 3.31 3.26 2.6 3.59 2.89 2.61 3.39

BFDMN (2014) 2.61 3.51 3.45 2.6 3.34 2.64 2.58 3.37

Dimensionless BFDMN (2012-2013) 1.07 0.89 1.12 1.19 1.07 1.08 1.11 0.99 1.06

Dimensionless BFDMN (2013-2014) 1.08 1.06 1.06 1.00 0.93 0.91 0.99 0.99 1.00

BFDMX (2012 As-Built) 3.51 6.6 4.46 3.86 7.87 4.46 3.7 6.52

BFDMX (2013) 3.92 4.6 5.65 4.37 8.53 5.06 4.91 5.94

BFDMX (2014) 3.95 5.08 5.78 4.6 8.77 4.81 4.87 6.19

% Change in BFDMX (2012-2013) 1.12 0.70 1.27 1.13 1.08 1.13 1.33 0.91 1.08

% Change in BFDMX (2013-2014) 1.01 1.10 1.02 1.05 1.03 0.95 0.99 1.04 1.03

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Should these variables be monitored through the project reach and dimensionless variables exist around 1.0, this would mean no changes were noticed and the channel is currently maintaining stability and not in a state of transition or further channel succession. Should the dimensionless variables approach the thresholds listed in table 2.2 it can be expected that channel succession is actively occurring. As table 2.3 suggests, no active channel succession is or has occurred within the project reach. In terms of channel dimensions the restoration techniques employed have proven successful in terms of maintaining a stable channel as designed that display no signs of unstable transitions through two average runoff seasons. This success in stability directly relates to near bank stress. This will allow the planted riparian vegetation to continue to flourish and add to floodplain function and bank stability.

1.14 Project Channel Profile The 2013 and 2014 post runoff longitudinal profiles encompassed all of the 500 feet of channel which was reconstructed in 2012. The vertical stability of the newly constructed channel can be assessed in relation to the runoff events experienced in water years 2013 and 2014. As well as sediment entrainment, the vertical stability of a reach lends inferences about vegetative potential and the static groundwater elevation in the hyporheic regions of the floodplain. Facet slopes have been measured from the 2012 as-built profile as well as the 2013 and 2014 post runoff profiles. Table 2.4 below displays the % change from as-built in terms of profile and pattern related to water years 2013 and 2014.

Figure 1.30. Vermilion Project Reach longitudinal profile of 2013 and 2014.

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Table 1.15 Summary of monitored pattern and profile As-built reach variables 2012 -2013 - 2014

Dimension Variables Riffles Runs Pools Glides

Mean Reach

Average Slope (2012 As-Built) 0.023 0.143 0.003 0.009 .024 Average Slope (2013 Post run-off) 0.023 0.130 0.003 0.013 .024 Average Slope (2014 Post run-off) 0.023 0.138 0.003 0.014 .024

% Change in Slope (2012-2013) 0 9 0 8 4 % Change in Slope (2013-2014) 0 6 0 8 7 Sinuosity (2012 As-Built) 1.08 Sinuosity (2013 Post run-off) 1.08 Sinuosity (2014 Post run-off) 1.08

% Change in Sinuosity (2012-2013) 0 % Change in Sinuosity (2013-2014) 0

Changes in channel elevation were noticed in certain design features. This was to be expected as the as-built channel went through a cleansing flow upon the first substantial run-off event post construction in 2013. None of these changes led to loss of integrity in structure or bank strength. In the more constricted areas changes led to the slight down cutting around the mid-channel boulder features (station 1+22 – 1+75). These areas were constructed to constrict the channel and provide for the “run” type features that aide in pool maintenance and function. Although the boulder placements have not changed in elevation the margins have deepened to provide for a deeper channel. The cobble “throats” were designed to move under bankfull or higher flow and have slightly. These areas were further monitored through the next event cycle of 2014 and little change is occurring. Additional pool habitat formed in areas below the constructed cobble pool tails in 2013 while maintaining the same water surface elevation (station 1+74 – 2+30). This is positive in terms of overall pool volume. The glide or pool tail areas seem to be sorting material as the pools have overall gotten deeper and longer. Very little deposition occurred throughout the reach. Most other changes related to the ebb and flow of natural sediment transport and did not pose any risks. Although very similar in terms of water year to that of 2013 (see figs. 1.15, 1.16) the channel bottom within the project reach seemed to have somewhat stabilized through the 2014 runoff season. Slight changes in channel features were observed. A few pools and glides deepened and further sorted a portion of the residual substrate. Riffles maintained grade. Wood structures at the lower end of the project reach seemed to have collected more material and created additional pool volume from that of the previous year. It could be expected that as long as sediment is being transported through the system some degree of channel fluctuation will occur through each runoff cycle. The descriptor that explains whether or not the channel elevation was maintained through the 2013 and 2014 flow events is the overall change in reach slope post run-off. As is displayed in table 2.4 the mean slope of the channel did not change with the 2013 or 2014 flow events and related sediment transport, nor did the planned structures create active headcutting or channel avulsions.

1.15 Reference Channel Profile The vertical stability of the reference channel upstream of the project site was assessed in relation to the runoff events experienced in water years 2013 and 2014.

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Facet slopes have been measured from the 2013 and 2014 post runoff profiles within the reference reach. Table 2.5 below displays the % change in terms of profile and pattern related to water year 2014.

Figure 1.31. Vermilion Reference Reach longitudinal profile of 2013 and 2014.

Table 1.16 Summary of monitored pattern and profile reference reach variables 2013 - 2014

Dimension Variables Riffles Runs Pools Glides

Mean Reach

Average Slope (2013 Post run-off) 0.023 0.205 0.005 0.017 Average Slope (2014 Post run-off) 0.023 0.183 0.005 0.015

% Change in Slope (2013-2014) 0 11 0 13 6 Sinuosity (2013 Post run-off) 1.07 Sinuosity (2014 Post run-off) 1.07

% Change in Sinuosity (2013-2014) 0

Vertical stability measured by water surface facet slopes within the reference reach changed slightly through the 2014 runoff period. All changes were within expected tolerances and very similar to changes monitored within the as-built project reach. Both reaches were subject to the same flow regime in 2014.

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1.16 Substrate Monitoring – Project Reach Wolman pebble counts were completed within 3 cross sections and the entire project reach in 2013, and repeated in 2014 following the peakflow events of both years. As-built pebble counts were not surveyed immediately after construction in 2012 as it was thought that these samples would be biased from the related instream silt. The runoff events of 2013 allowed for this minor amount of “construction silt” to be transported out of the project reach.

Table 1.17 Riffle and reach particle size distribution within the project reach

Cumulative % and Finer XS#1

(Riffle) 2013

XS#1 (Riffle) 2014

XS#4 (Riffle) 2013

XS#4 (Riffle) 2014

XS#7 (Riffle) 2013

XS#7 (Riffle) 2014

Reach 2013

Reach 2014

D16 24 11 2 3 11 8 22 13 D50 84 53 25 25 44 40 121 57 D84 222 176 306 152 204 231 244 252 D95 362 340 495 507 446 482 495 401

Silt / Clay (<.062 mm) 2 0 0 0 0 0 0 0

Sand (.062 – 2.0 mm) 0 0 17 14 0 3 2 0

Gravel (2.0 – 64 mm) 39 55 54 59 62 59 33 54

Cobble (64 – 256 mm) 47 37 9 14 28 23 55 30

Boulder (256 – 2048 mm) 12 9 19 14 9 15 11 16

Bedrock (> 2048 mm) 0 0 0 0 0 0 0 0

In terms of the channel substrate below the bankfull elevation, slight fluctuations were noticed within the riffles and the entire reach. These changes corresponded well with the minor dimension fluctuations noticed in the surveyed cross sections. A certain level of fluctuation can also be expected within this type of survey as the protocol requires random particle samples being measured in different locations each year. Substrate fluctuations of this low magnitude further support the other trends in stability throughout the project reach.

1.17 Substrate Monitoring – Reference Reach Wolman pebble counts were completed within 2 cross sections and the entire reference reach in 2013 post runoff. These activities were replicated in 2014 following the corresponding peakflow events. Pebble counts were surveyed in 2013 and 2014 to compliment the surveys done within the project reach. Together these two data sets monitor major changes happening naturally that may influence depositional and transport functions within this area of the Vermilion River. Similar to the downstream project reach slight shifts in substrate composition have occurred in the reference reach. None of these shifts however are influencing channel function and stability of the reference or the project reach. Although still a small percentage of the total substrate composition, both the reference and project reaches noticed similar changes in the % sand within the reach. This was either associated with a seasonal flush of upstream fines, with slight deposition through both reaches, or more likely related to survey inconsistencies between the two years. The change in boulder substrate in the reference reach is likely due to survey error, as the flows through the water year were not substantial enough to transport this size of material.

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Table 1.18 Riffle and reach particle size distribution within the upstream reference reach.

Cumulative % and Finer XS#2

(Riffle) 2013

XS#2 (Riffle) 2014

XS#4 (Riffle) 2013

XS#4 (Riffle) 2014

Reach 2013

Reach 2014

D16 12 2 8 14 22 25 D50 75 37 49 45 121 107 D84 224 165 116 163 244 350 D95 338 288 180 245 495 851

Silt / Clay (<.062 mm) 2 2 0 0 0 0

Sand (.062 – 2.0 mm) 8 14 4 9 2 4

Gravel (2.0 – 64 mm) 35 45 57 50 33 31

Cobble (64 – 256 mm) 44 33 38 38 55 41

Boulder (256 – 2048 mm) 12 6 1 4 11 25

Bedrock (> 2048 mm) 0 0 0 0 0 0

Table 1.19 Comparison of Vermilion reference and Chapel Slide substrate reach variables 2013 - 2014

Substrate Size Class Variables Mean Reach - Vermilion Reference (2013-2014)

Mean Reach – Chapel Slide Restoration (2013-2014)

% Change in Silt / Clay (<.062 mm) 0 25

% Change in Sand (.062 – 2.0 mm) 100 46

% Change in Gravel (2.0 – 64 mm) 3 27

% Change in Cobble (64 – 256 mm) 17 7

% Change in Boulder (256 – 2048 mm) 51 15

% Change in Bedrock (> 2048 mm) 0 0

Figure 1.32. Substrate variable percent change within the project and reference reach through 2013 and 2014.

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1.18 Conclusions The effectiveness monitoring of the stream restoration activities completed in 2012 have supported the perception that the newly constructed channel remained resilient through multiple bankfull flow (Q1.5) events through the first two years of runoff. This report provides for the initial baseline monitoring of the initial most upstream project reach in the mainstem of the Vermilion River. This effort has given some idea of not only the stability within the constructed reach but the overall trend of specific parameters such as aggradational and degradational processes in relation to the applied design. Structure integrity has been assessed, and demonstrated that as-built channel conditions can maintain through multiple average runoff events associated with the hydrology of the Vermilion River basin. Revegetation of native shrubs that were completed in 2013 are responding well, will be further monitored and will add to the bank integrity once fully established. Results display that the Chapel Slide restoration is maintaining and trending towards a stable fully functioning system. No repairs are needed and at the current time the restoration approaches seem appropriate and resilient to the flows associated with an average year in the Vermilion River system. Avista Utilities and Montana Fish Wildlife and Parks (MTFWP) have supported this physical monitoring effort by continuing to sample fish population density and diversity within this reach of the Vermilion River. Eventually the expectation is to link these two data sets over time in a hydro ecological setting to arrive at conclusions surrounding the impacts of this type of work in a priority Bull Trout watershed. The next downstream project is the Miners Gulch reach which is currently in the planning and design phase. Approaches and lessons learned through this montoring effort will compliment design and aide in this projects success.

1.19 References Harrelson, C.C., Rawlins, C.L., and Potyondy, J.P. 1994. Stream Channel Reference Sites:An Illustrated Guide to Field Technique. Gen Tech Rep RM-245. Fort Collins, CO: U.S. Dept of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. Neesvig, C., D. Grupenhoff, A. Reif, 2007. Vermilion River Watershed Assessment and Preliminary Restoration Plan. USDA Forest Service Kootenai National Forest, Libby, Montana RIVERMorph LLC. 2005. Stream Restoration Software. Louisville, Kentucky 40223-2177. Wolman, M.G. 1954. A method of sampling coarse river-bed gravel. Transactions of American Geophysical Union 35: 951-956.

USFS, Cabinet Ranger District, 2013. Vermilion River at the red bridge 2013 Water Quality Data Report. Unpublished. USFS, Cabinet Ranger District, 2014. Vermilion River at the red bridge 2014 Water Quality Data Report. Unpublished.

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