AOP_Hydraulics_Report_FSR_1050_MP_1.7.pdf

U.S. DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

WESTERN FEDERAL LANDS HIGHWAY DIVISION

610 east Fifth street Vancouver Washington, 98661

AQUATIC ORGANISM PASSAGE HYDRAULICS REPORT

To: Betty Chon, Project Manager WFLHD From: James Neighorn, Hydraulics Engineer WFLHD Date: December 18, 2017 Project: WA FS ERFO 2016(1)-20(1) Mt. Baker Emergency Repairs

Project Description

The Forest Service is replacing a failed culvert on forest service road (FSR) 1050 at mile post (MP) 1.7, on the Mt. Baker National Forest, Skagit County, Washington (see Fig. 1). The Forest Service will maintain the new structure. Western Federal Lands Highway Division (WFLHD) is designing the replacement structure. This report presents the recommendations for the proposed aquatic organism passage (AOP) structure.

AOP Design Criteria

Forest Service biologists confirmed that the FSR 1050 (MP 1.7) crossing would require an aquatic organism passage (AOP) structure.

The crossing is located on an unnamed tributary to Diobsud Creek. This unnamed tributary provides spawning and rearing habitat for bull trout which are federally listed Endangered Species Act (ESA) anadromous fish species. Constructing passable structures at this location will allow their passage to critical habitat.

Fish passage is required by Washington Administrative Code (WAC) 220-660-190, the Endangered Species Act (ESA), and the Magnuson-Stevens Fishery Conservation and Management Act. The recommended fish passage crossing design is consistent with requirements of the Aquatic Restoration Biological Opinion II (ARBOII).

The proposed AOP structure has been designed per Stream Simulation: An Ecological Approach to Providing Passage for Aquatic Organisms at Road-Stream Crossings (USDA-Forest Service 2008).

This method provides a simplified design methodology that is intended to mimic natural upstream and downstream processes within the culvert. Fish passage, sediment transport, and debris conveyance within the culvert are designed to function as they would in the adjacent natural channel.

Determination of the high and low fish passage design flows, water velocity, and water depth is not required for this method since the stream hydraulic characteristics within the culvert are intended to mimic the stream conditions upstream and downstream of the crossing. The method utilizes streambed materials that are similar to the adjacent channel, providing similar channel complexity, flow depth, flow velocities, and resting areas. The following requirements have been incorporated

Mt. Baker Emergency Repairs – AOP Hydraulic Report 2 12/18/2017 into the AOP design:

Flood Conveyance: Culvert capacity exceeds the 100-year recurrence flood without roadway overtopping.

Culvert Width: Must accommodate the design channel bankfull width plus additional width for construction of stable bank rocks along both sides of the channel inside the culvert. The minimum culvert bed width is 1.3 times the bankfull channel width for non-entrenched streams. For entrenched streams (entrenchment ratio < 1.4) the minimum width is bankfull channel width plus room for natural channel banks.

Channel Vertical Clearance: Clearance from bed to ceiling must be at least 5 feet to allow for ease of construction, maintenance, and debris removal.

Channel Slope: Reconstructed streambed within the culvert should approximate the average slope of the adjacent stream from approximately ten channel widths upstream and downstream of the culvert site, and should not deviate by more than 1%.

Embedment: Bottom of the culverts should be buried into the streambed between 30 and 50 percent of the culvert height, and a minimum of 3 feet.

Maximum Length of Road Crossing: Length should be less than 150 feet.

Fill Materials: Fill materials are comprised of material similar in size composition to natural bed materials that form the natural stream channels adjacent to the road crossing. Larger material is added for assisting stream gradient retention and providing resting areas for migrating fish.

Water Depth and Velocity: Water depth and velocity in the culvert must closely resemble those existing in the adjacent stream.

FSR 1050 (MP 1.7)

The existing 6-foot diameter corrugated aluminum pipe was completely plugged by wood debris at the inlet during flooding. This resulted in flows overtopping and washing out the roadway above the pipe. Deposition of cobble and gravel material has occurred immediately upstream of the culvert as a result of the plugging. The pipe is in good condition and is perched about 24-inches above a 36-inch deep plunge pool at the outlet. The culvert is located approximately 1 mile upstream from the confluence with Diobsub Creek. The existing culvert is slightly skewed (10 degrees) and does not match the stream alignment which is near perpendicular to the road alignment.

The stream slope ranges between 12 and 15 percent, with upstream bankfull widths of 14.5 feet.

Ordinary high water depths vary from 14 to 30 inches. Flood prone limits ranging from 16 to 20 feet wide. Step pool is the dominant bed form. The steps are formed by cobbles with small to medium sized boulders. The valley walls prevent the stream from laterally migrating and banks appear well vegetated and stable. Because of the confining valley walls, the stream is entrenched with an entrenchment ratio of between 1.1 and 1.4. The stream shows no sign of recent aggradation

Mt. Baker Emergency Repairs – AOP Hydraulic Report 3 or degradation within the reach. Approximately 150 feet downstream of the crossing, a pocket of larger boulders has formed a nick point where the channel bottom drops about 5 feet over a short distance. Future erosion around the larger boulders could result in upstream migration of the nick point and lowering of the channel bottom at the crossing location. Boulders in the channel range in size from 12 to 48 inches. Estimated streambed material gradation using field measurements and photo analysis for upstream and downstream of the crossing is D100 13-inches, D85 8-inches, D50 4-inches and D15 2-inches.

The stream has the capacity to transports moderate quantities woody consisting of 12 to 16-foot length,18-inch diameter logs during larger storm events. Larger 24-inch plus diameter trees that have fallen within the flood prone area do not appear to be transported by flood flows. The risk for occurrence of debris flows is low.

Recommendations:

Use a bankfull channel width of 14.5 feet for designing the AOP pipe.

Replace the culvert with an 18-foot wide by 12-foot deep, 30-foot long precast concrete box culvert.

Install the culvert perpendicular to the road alignment to match the existing stream alignment.

Slope the pipe and bed material inside the pipe to match the natural stream gradient, approximately 14 percent.

Embed the culvert a minimum of 5 feet to accommodate scour and possible degradation.

Backfill the culvert interior with streambed material conserved from excavating for the culvert. If the conserved streambed material quantity is insufficient for backfilling the culvert, use material similar to the natural streambed material meeting the gradation specified in the attached SCR (see Appendix E).

The steep stream gradient will require that retention sills be installed along the bottom of the culvert to help retain streambed material. Set the top of the retention sills below the design bed gradient and install rock weirs flush with the streambed grade at each sill location. The rock weirs will provide a more natural roughness and act together with the sills to enhance retention within the culvert.

Space the sills and rock weirs at approximately 10 foot intervals to match the natural step spacing of the upstream channel.

Construct rock weirs in a manner that provides irregular openings or low flow gaps at the center of the low flow channel.

To create a low flow channel and provide resting opportunities for fish, install interior banks and fish passage boulders (habitat stones), as shown on Drawing E.6 (see Appendix D).

Install headwalls and wingwalls at the culvert inlet and outlet to reduce the culvert length and minimize grading work into the active channel and floodplain areas.

Mt. Baker Emergency Repairs – AOP Hydraulic Report 4

Place a 3-foot minimum thickness of class 3 riprap at each end of the culvert to prevent scour and undermining of the structure in the event that the channel degrades.

No modification of the road alignment or profile is needed for accommodating the proposed culvert design.

Construction

Work within the ordinary-high-water limits can only be performed between June 15 and July 31.

Temporary flow deflectors placed for isolating the work area and diverting the stream flows must have a minimum height of 2 feet above the stream bottom and be stable assuming 9.6 feet per second parallel flow and 1.5 feet maximum water depth. Assuming in-stream construction occurs June 15 through July 31; temporary flow diversions must have a minimum flow capacity equal to one-half the 2-year discharge noted on the plans. Before installing the flow deflectors, remove fish from the work area to the level and methods specified in the environmental permits.

Access for culvert installation work will be accomplished adjacent to the existing highway road embankment footprint. Temporary access routes down and adjacent to the road embankments are needed for installing flow barriers and completing culvert inlet, interior, and outlet work.

The State of Washington and the U.S. Fish and Wildlife Service will restrict the release of turbidity from the work areas into the stream. The agencies require turbidity control and monitoring, and should be contacted for specific requirements and allowable discharge limits.

Stream Impacts

The proposed fish passage culvert is expected to dramatically improve stream flow conveyance, sediment transport, and woody debris transport to a level that is similar to the adjacent natural streams.

A moderate amount of turbidity and sediment is expected to be released downstream into the creek when the flow barriers are removed and stream flow is introduced into the newly constructed culvert.

The amount of turbidity and sediment will be reduced by removing the flow barriers gradually and introducing the stream flow over an extended two to three hour time period.

Floodplain and Flood-rise Impacts

Flood limits and elevations have not been mapped by the National Flood Insurance Program for the site. The proposed culverts will improve hydraulic conveyance and is not expected to impact flooding at the site.

Operation and Maintenance

Rock weirs and retention sills may tend to collect debris within the culverts. Scour or aggradation of the streambed is also expected to occur to some extent, as would be expected for the natural stream. Monitoring at regular intervals, and ideally during flood events, will be especially important

Mt. Baker Emergency Repairs – AOP Hydraulic Report 5 during the first few years to ensure that excessive debris accumulation, scour, or aggradation does not impair passage through the culvert. The Forest Service should increase the frequency of culvert inspections and debris removal for the first three years. Rock weirs and fish boulders placed within the culvert and stream channel should be inspected annually and after each extreme flood event to ensure effective backwater and bed retention. Replace or reposition dislodged rocks or boulders.

Additional rock may need to be installed to correct erosion or channel degradation.

Hydrology

The creeks at the site is unregulated and un-gaged. Therefore, peak discharges were estimated using USGS regression equations from Magnitude and Frequency of Floods in Washington (USGS Report 97-4277). The drainage area and mean annual precipitation were determined using the USGS StreamStats program. The drainage area was 0.71 square miles and the mean annual precipitation was 88.3 inches. Peak discharges estimates are presented in Table 1.

cc: Sven Leon, WFLHD Senior Hydraulics Engineer

Attachments: Table 1 Appendix A – Figures Appendix B – Photos Appendix C – Calculations Appendix D – Preliminary Plans and Details Appendix E – Special Contract Requirements (SCRs)

Mt. Baker Emergency Repairs – AOP Hydraulic Report 6

Table 1.

AOP Design Summary

B an k fu ll

W id th Culvert

Peak Discharge (ft3/sec)

Site Span

Rise

Burial

Slope

2-year

50-

100-

(ft) (ft) (ft) (ft) (%)

FSR 1050 MP 1.7 14.5 18 12 5 - 7 6.56 1 58 163 184

Notes:

BFW = Bankfull width.

1. Culvert slope set at 6.56% with a streambed slope of 14.14%

Appendix A – Figures

[This page intentionally left blank.]

AOP Culvert Location

Project Site Location

Map printed from Google Earth Pro, image date 7/2016.

N

48.583050 / -121.422070

FIGURE 1

FSR 1050 MP 1.7 CULVERT

SITE LOCATION

Map Printed from StreamStats (Ver. 3.0)

N

FIGURE 2

FSR 1050 MP 1.7 CULVERT

DRAINAGE AREA

FSR 1050 MP 1.7

DA = 0.71 sq. mi.

Appendix B – Photos

Photos FSR 1050 MP 1.7

PHOTO 1

PHOTO 2

PHOTO 3

9/6/2017

Channel scoured 5 feet deep at culvert outfall.

Plugged with wood debris.

Culvert - Outlet area.

Culvert - Existing road alignment.

Embankment washed out around culvert.

Culvert - Inlet area.

PHOTO 4

PHOTO 5

PHOTO 6

9/6/2017

Banks well defined. Step pool dominant bed form. Boulder-cobble streambed material.

Inside culvert looking towards inlet.

Inlet completely plugged by debris.

Culvert in good condition.

Channel upstream of culvert.

Wood tranported lengths of 12 to 16 feet with 12 to 18 inch diameter. Channel bed material consists of approximate D100 of 3.5 feet.

Upstream channel, active channel width measurement location.

PHOTO 7

PHOTO 8

PHOTO 9

9/6/2017

Upstream channel, active channel width measurement location.

Typical cobble-boulder streambed material.

Banks well defined. Step pool dominant bed form. Boulder-cobble streambed material.

Cobble and small to larger boulders.

Downstream channel.

Larger boulders exposed near culvert outlet. Banks well vegetated.

PHOTO 10

PHOTO 11

PHOTO 12

9/6/2017

Typical gravel cobble streambed material.

Cobbles and gravel.

Typical wood debris within the channel.

Smaller diameter (under 24-inches) and shorter log lengths up to 16 foot are being transported by the creek.

Larger boulders forming grade control (nick point) downstream of crossing.

The channel bottom drop approximately 5' just below the large boulder cluster.

Appendix C – Calculations

Basin Characteristics Ungaged Site Report

Date: Fri May 19, 2017 7:23:27 AM GMT-7 Study Area: Washington NAD 1983 Latitude: 48.5832 ( 48 34 59) NAD 1983 Longitude: -121.4215 (-121 25 18)

Label Value Units Definition

DRNAREA 0.71 square miles Area that drains to a point on a stream RELIEF 3080 feet Maximum - minimum elevation ELEVMAX 3950 feet Maximum basin elevation MINBELEV 870 feet Minimum basin elevation ELEV 2560 feet Mean Basin Elevation

CANOPY_PCT 86.3 percent Percentage of drainage area covered by canopy as described in OK

SIR 2009_5267

PRECIP 88.3 inches Mean Annual Precipitation

SLOP30_30M 79 percent Percent area with slopes greater than 30 percent from 30-meter

DEM.

BSLDEM30M 43.5 percent Mean basin slope computed from 30 m DEM NFSL30 0.2 percent North-Facing Slopes Greater Than 30 Percent

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Flow Statistics Ungaged Site Report Date: Fri May 19, 2017 7:26:05 AM GMT-7 Study Area: Washington NAD 1983 Latitude: 48.5832 ( 48 34 59) NAD 1983 Longitude: -121.4215 (-121 25 18) Drainage Area: 0.71 mi2

Peak-Flow Basin Characteristics

100% Region 2 (0.71 mi2)

Parameter Value Regression Equation Valid Range Min Max

Drainage Area (square miles) 0.71 0.08 3020 Mean Annual Precipitation (inches) 88.3 23 170

Peak-Flow Statistics

Statistic Value Unit Standard Error (percent) Equivalent years of record 90-Percent Prediction Interval

Min Max PK2 57.8 cfs 56 1 PK10 109 cfs 53 1 PK25 137 cfs 53 2 PK50 163 cfs 53 2 PK100 184 cfs 54 3 PK500 247 cfs http://pubs.er.usgs.gov/usgspubs/wri/wri974277 (http://pubs.er.usgs.gov/usgspubs/wri/wri974277) Sumioka_ S.S._ Kresch_ D.L._ and Kasnick_ K.D._ 1998_ Magnitude and Frequency of Floods in Washington: U.S. Geological Survey Water-Resources Investigations Report 97-4277_ 91 p.

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HY-8 Culvert Analysis Report

Project Notes

Project Title:WA ERFO 2016(1)-20(1) Mt Baker - FSR 1050 MP 1.7

Designer:James Neighorn

Project Date:Tuesday, December 12, 2017

Notes:

AOP Culvert Design Report

Crossing Discharge Data

Discharge Selection Method: Specify Minimum, Design, and Maximum Flow

Minimum Flow: 58 cfs

Design Flow: 163 cfs

Maximum Flow: 184 cfs

Table 1 - Summary of Culvert Flows at Crossing: Mt Baker Headwater Elevation

(ft) Total Discharge (cfs) FSR 1050 MP 1.7

Discharge (cfs) Roadway Discharge

(cfs) Iterations

996.18 58.00 58.00 0.00 1

996.31 70.60 70.60 0.00 1

996.43 83.20 83.20 0.00 1

996.55 95.80 95.80 0.00 1

996.66 108.40 108.40 0.00 1

996.77 121.00 121.00 0.00 1

996.87 133.60 133.60 0.00 1

996.97 146.20 146.20 0.00 1

997.07 158.80 158.80 0.00 1

997.10 163.00 163.00 0.00 1

997.26 184.00 184.00 0.00 1

1003.00 1001.73 1001.73 0.00 Overtopping

Table 2 - Culvert Summary Table: FSR 1050 MP 1.7 Total

Discharge (cfs)

Culvert Discharge

(cfs)

Headwater Elevation (ft)

Inlet Control Depth (ft)

Outlet Control

Depth (ft)

Flow Type

Normal Depth (ft)

Critical Depth (ft)

Outlet Depth (ft)

Tailwater Depth (ft)

Outlet Velocity

(ft/s)

Tailwater Velocity

(ft/s)

58.00 58.00 996.18 0.928 0.0* 1-S2n 0.544 0.678 0.544 0.502 5.769 7.452

70.60 70.60 996.31 1.058 0.0* 1-S2n 0.613 0.772 0.613 0.564 6.235 8.007

83.20 83.20 996.43 1.181 0.0* 1-S2n 0.676 0.863 0.676 0.622 6.658 8.500

95.80 95.80 996.55 1.300 0.0* 1-S2n 0.737 0.959 0.737 0.676 7.041 8.944

108.40 108.40 996.66 1.414 0.0* 1-S2n 0.794 1.049 0.809 0.727 7.251 9.348

121.00 121.00 996.77 1.521 0.0* 1-S2n 0.847 1.128 0.847 0.775 7.729 9.722

133.60 133.60 996.87 1.624 0.0* 1-S2n 0.901 1.202 0.901 0.822 8.029 10.068

146.20 146.20 996.97 1.725 0.0* 1-S2n 0.950 1.277 0.975 0.867 8.118 10.393

158.80 158.80 997.07 1.823 0.0* 1-S2n 0.998 1.350 0.998 0.910 8.610 10.697

163.00 163.00 997.10 1.855 0.0* 1-S2n 1.015 1.374 1.042 0.924 8.465 10.795

184.00 184.00 997.26 2.010 0.0* 1-S2n 1.090 1.485 1.121 0.992 8.882 11.258

Straight Culvert

Inlet Elevation (invert): 995.25 ft, Outlet Elevation (invert): 993.29 ft

Culvert Length: 30.06 ft, Culvert Slope: 0.0653

Site Data - FSR 1050 MP 1.7

Site Data Option: Culvert Invert Data

Inlet Station: 0.00 ft

Inlet Elevation: 988.25 ft

Outlet Station: 30.00 ft

Outlet Elevation: 986.29 ft

Number of Barrels: 1

Culvert Data Summary - FSR 1050 MP 1.7

Barrel Shape: Concrete Box

Barrel Span: 18.00 ft

Barrel Rise: 12.00 ft

Barrel Material: Concrete

Embedment: 84.00 in

Barrel Manning's n: 0.0120 (top and sides)

Manning's n: 0.0450 (bottom)

Culvert Type: Straight

Inlet Configuration: Square Edge with Headwall

Inlet Depression: None

Table 3 - Downstream Channel Rating Curve (Crossing: Mt Baker)

Flow (cfs) Water Surface Elev (ft)

Depth (ft) Velocity (ft/s) Shear (psf) Froude Number

58.00 991.79 0.50 7.45 4.43 1.91

70.60 991.85 0.56 8.01 4.98 1.95

83.20 991.91 0.62 8.50 5.49 1.97

95.80 991.97 0.68 8.94 5.96 2.00

108.40 992.02 0.73 9.35 6.41 2.02

121.00 992.07 0.78 9.72 6.84 2.04

133.60 992.11 0.82 10.07 7.25 2.05

146.20 992.16 0.87 10.39 7.65 2.07

158.80 992.20 0.91 10.70 8.03 2.08

163.00 992.21 0.92 10.79 8.15 2.09

184.00 992.28 0.99 11.26 8.75 2.11

Tailwater Channel Data - Mt Baker

Tailwater Channel Option: Trapezoidal Channel

Bottom Width: 14.50 ft

Side Slope (H:V): 2.00 (_:1)

Channel Slope: 0.1414

Channel Manning's n: 0.0450

Channel Invert Elevation: 991.29 ft

Roadway Data for Crossing: Mt Baker

Roadway Profile Shape: Constant Roadway Elevation

Crest Length: 1000.00 ft

Crest Elevation: 1003.00 ft

Roadway Surface: Paved

Roadway Top Width: 18.00 ft

Hydraulic Analysis Report

Project Data

Project Title: FSR 1050 Bankfull and Entrenchment Analysis

Designer:

Project Date: Thursday, December 14, 2017

Project Units: U.S. Customary Units

Notes:

Channel Analysis: Upstream Channel Depth 2yr

Notes:

Input Parameters

Channel Type: Custom Cross Section

Cross Section Data Elevation (ft) Elevation (ft) Manning's n

0.00 1030.68 0.0450

1.89 1029.85 0.0450

4.93 1028.09 0.0450

6.80 1028.03 0.0450

13.85 1027.63 0.0450

16.99 1026.50 0.0450

25.27 1022.22 0.0450

27.93 1022.04 0.0450

32.55 1023.40 0.0450

36.56 1023.54 0.0450

41.80 1025.79 0.0450

45.05 1029.25 0.0450

47.76 1031.03 -----

Longitudinal Slope: 0.1414 ft/ft

Flow: 58.0000 cfs

Result Parameters

Depth: 1.1580 ft

Area of Flow: 6.0441 ft^2

Wetted Perimeter: 8.8969 ft

Hydraulic Radius: 0.6794 ft

Average Velocity: 9.5961 ft/s

Top Width: 8.4860 ft

Froude Number: 2.0038

Critical Depth: 1.6388 ft

Critical Velocity: 5.0580 ft/s

Critical Slope: 0.0336 ft/ft

Critical Top Width: 14.44 ft

Calculated Max Shear Stress: 10.2178 lb/ft^2

Calculated Avg Shear Stress: 5.9942 lb/ft^2

Composite Manning's n Equation: Lotter method

Manning's n: 0.0450

Channel Analysis: Upstream Channel 2xDepth 2yr

0.00 1030.68 0.0450

1.89 1029.85 0.0450

4.93 1028.09 0.0450

6.80 1028.03 0.0450

13.85 1027.63 0.0450

16.99 1026.50 0.0450

25.27 1022.22 0.0450

27.93 1022.04 0.0450

32.55 1023.40 0.0450

36.56 1023.54 0.0450

41.80 1025.79 0.0450

45.05 1029.25 0.0450

47.76 1031.03 -----

Depth: 2.3000 ft

Result Parameters

Flow: 309.3806 cfs

Area of Flow: 21.9443 ft^2

Wetted Perimeter: 18.1390 ft

Hydraulic Radius: 1.2098 ft

Average Velocity: 14.0984 ft/s

Top Width: 17.2544 ft

Froude Number: 2.2031

Critical Depth: 3.2285 ft

Critical Velocity: 7.7729 ft/s

Critical Slope: 0.0259 ft/ft

Critical Top Width: 21.21 ft

Calculated Max Shear Stress: 20.2937 lb/ft^2

Calculated Avg Shear Stress: 10.6744 lb/ft^2

Channel Analysis: Downstream Channel Depth 2yr

0.00 984.52 0.0450

7.33 982.82 0.0450

14.39 981.69 0.0450

15.97 979.35 0.0450

16.87 978.07 0.0450

20.72 976.94 0.0450

24.56 976.54 0.0450

25.97 977.63 0.0450

29.30 978.92 0.0450

30.40 978.63 0.0450

32.15 978.72 0.0450

32.67 980.31 0.0450

39.42 981.31 0.0450

43.05 980.11 0.0450

45.93 980.46 0.0450

54.71 981.61 0.0450

57.97 981.41 0.0450

58.08 981.55 -----

Flow: 58.0000 cfs

Result Parameters

Depth: 1.2220 ft

Area of Flow: 6.0523 ft^2

Wetted Perimeter: 8.9269 ft

Hydraulic Radius: 0.6780 ft

Average Velocity: 9.5832 ft/s

Top Width: 8.3911 ft

Froude Number: 1.9885

Critical Depth: 1.6690 ft

Critical Velocity: 5.5899 ft/s

Critical Slope: 0.0326 ft/ft

Critical Top Width: 10.69 ft

Calculated Max Shear Stress: 10.7818 lb/ft^2

Calculated Avg Shear Stress: 5.9821 lb/ft^2

Channel Analysis: Downstream Channel 2xDepth 2yr

0.00 984.52 0.0450

7.33 982.82 0.0450

14.39 981.69 0.0450

15.97 979.35 0.0450

16.87 978.07 0.0450

20.72 976.94 0.0450

24.56 976.54 0.0450

25.97 977.63 0.0450

29.30 978.92 0.0450

30.40 978.63 0.0450

32.15 978.72 0.0450

32.67 980.31 0.0450

39.42 981.31 0.0450

43.05 980.11 0.0450

45.93 980.46 0.0450

54.71 981.61 0.0450

57.97 981.41 0.0450

58.08 981.55 -----

Depth: 2.4400 ft

Result Parameters

Flow: 279.6694 cfs

Area of Flow: 20.3614 ft^2

Wetted Perimeter: 17.5024 ft

Hydraulic Radius: 1.1633 ft

Average Velocity: 13.7353 ft/s

Top Width: 16.0049 ft

Froude Number: 2.1460

Critical Depth: 3.2986 ft

Critical Velocity: 8.1111 ft/s

Critical Slope: 0.0281 ft/ft

Critical Top Width: 16.88 ft

Calculated Max Shear Stress: 21.5290 lb/ft^2

Calculated Avg Shear Stress: 10.2646 lb/ft^2

RIPRAP DESIGN - USACE

Project: File:

Desc: By: Date:

CULVERT INLET AND OUTLET

Riprap

Slope Description Class Vavg D Tdes Sb Phi Vh SF Cs Cv Ct Gs (f/s) (ft) (ft) 85 50 30 15 (h:1v) (deg) (lb/ft3)

100-yr 1.4 1.9 2.2 2.7 0.1

1.5:1 5 8.9 1.0 4 1.4 1.9 2.2 2.7 1.50 42 1.0 1.3 0.3 1.0 1.0 155

5 8.9 1.0 4 1.4 1.9 2.2 2.7 1.50 42 1.0 1.4 0.3 1.0 1.0 155

6 8.9 1.0 5 1.4 1.9 2.2 2.7 1.50 42 1.0 1.5 0.3 1.0 1.0 155

6 8.9 1.0 5 1.4 1.9 2.2 2.7 1.50 42 1.0 1.6 0.3 1.0 1.0 155 6 8.9 1.0 5 1.4 1.9 2.2 2.7 1.50 42 1.0 1.7 0.3 1.0 1.0 155

1.75:1 4 8.9 1.0 4 1.4 1.9 2.2 2.7 1.75 42 1.0 1.3 0.3 1.0 1.0 155

4 8.9 1.0 4 1.4 1.9 2.2 2.7 1.75 42 1.0 1.4 0.3 1.0 1.0 155

4 8.9 1.0 4 1.4 1.9 2.2 2.7 1.75 42 1.0 1.5 0.3 1.0 1.0 155

5 8.9 1.0 4 1.4 1.9 2.2 2.7 1.75 42 1.0 1.6 0.3 1.0 1.0 155 5 8.9 1.0 4 1.4 1.9 2.2 2.7 1.75 42 1.0 1.7 0.3 1.0 1.0 155

2:1 DESIGN 3 8.9 1.0 3 1.4 1.9 2.2 2.7 2.00 42 1.0 1.3 0.3 1.0 1.0 155

3 8.9 1.0 3 1.4 1.9 2.2 2.7 2.00 42 1.0 1.4 0.3 1.0 1.0 155

4 8.9 1.0 4 1.4 1.9 2.2 2.7 2.00 42 1.0 1.5 0.3 1.0 1.0 155

4 8.9 1.0 4 1.4 1.9 2.2 2.7 2.00 42 1.0 1.6 0.3 1.0 1.0 155 4 8.9 1.0 4 1.4 1.9 2.2 2.7 2.00 42 1.0 1.7 0.3 1.0 1.0 155

Notes:

Approach from Army Corps of Engineers EM 1110-2-1601, Change 1, Jun 30, 1994, Chapter 3.

Vavg Local depth-averaged velocity.

D Local depth of flow.

Tdes Design riprap layer thickness. Largest of 2 x D50 or 1.2 x D100

Sb Bank sideslope (0 = Channel bottom analysis).

Phi Riprap angle of repose.

Vh Horizontal velocity correction factor (1.0 min).

SF Safety factor 1.3 minimum

Cs Stability (0.30 for angular rock, 0.38 for round rock).

Cv Vertical velocity distribution (1.0 straight, 1.3 typical bend, 1.5 sharp bend) Ct Thickness (0.5 for 2xTdes, 0.9 for 1.5xTdes)

Gs Unit weight of stone (155 lbs/ft3 min).

Gw Unit weight of water. 62 lbs/ft3 g Gravitational constant. 32 ft/s2

K1 Side slope correction = (1-(sin2Sb/sin2Phi))^0.5 (eq. 3-4)

D30 Sf*Cs*Cv*Ct*D*(((Gw/(Gs-Gw))^0.5)*((Vavg*Vh)/((K1*g*D)^0.5)))^2.5 (eq. 3-3)

D15 D100 / D100/15

D50 D100 / D100/50

D85 D100 / D100/85 D100 D100/30 * D30

C85/C15 Uniformity ratio (1.7 to 5.2)

Coefficients

Riprap Sizing - FSR 1050 MP 1.7

12/12/17

Design Input

WA ERFO 2016(1)-20(1) Mt Baker - FSR 1050 MP 1.7

Riprap channel bottom at culvert inlet and outlet

DESIGN: Class 3, 2(h):1(v), 3.0 feet thick.

D100/

Flow Riprap

Location

J. Neighorn

Appendix D – Preliminary Plans and Details

SCALE IN FEET

10 0 10 20 30 40

N

E.2

STATE PROJECT

NUMBER

SHEET

WA FS ERFO 2016(1)-20(1)

PLAN & PROFILE

AOP CULVERT

FSR 1050 MP 1.7

STATE PROJECT

NUMBER

SHEET

I n t_ ft

D c m y fi le s p w p r o d u c ti o n d w a e r l6 e b .d g n

A

M

D e c e m b e r

S

L e o

J

N e ig h o r

C h e c k e d b y

D e s ig n e d b y

LC

OUTLETINLETPIPEHYDRAULIC INFORMATION

0 20 40 60 8020406080

Proposed road

LENGTH: 30 ft

PIPE SLOPE: 0.0656 ft/ft

HEADWALL: Conc.

FLOWLINE SLOPE: 0.1414 ft/ft

:1

:1 centerline

New culvert

Existing ground

100 120100120140

Flow

Roadway

WALL THICKNESS: NA

Proposed road grade

HEADWALL: Conc.

Q : 184 CFS

Remove existing 72" dia. culvert

Remove existing 72" dia. culvert

FOOTNOTE:

Proposed channel flowline

SPAN: 18' - 0"Q : 58 CFS HW : 997.10 ft TYPE: Conc. Box RISE: 12' - 0"

BEVEL: NA

BURIAL DEPTH: 7 ft BURIAL DEPTH: 5 ft

LOWER BEVEL HEIGHT: NALOWER BEVEL HEIGHT: NA

BEVEL: NA

Slope 6.56%

BANKFULL CHANNEL WIDTH: 14.5'

[1]riprap end treatment method B, class 3

Placed riprap, [1]riprap end treatment method B, class 3

Placed riprap, [1]riprap end treatment method B, class 3

Placed riprap, [1]riprap end treatment method B, class 3

Placed riprap, Sta 702+39.7, Offset 17.78' LT

Proposed channel elev. 994.98

Proposed channel elev. 991.29

Q : 163 CFS

INV N/E/EL: 2047.88/1054.57/988.25 INV N/E/EL: 2017.96/1053.73/986.29

headwalls and wingwalls culvert (18' span x 12' rise) with

Proposed precast reinforced

Sta. 702+39.7

Fl ow boulders per detail Sheet E.6 material and fish passage

Backfill with streambed

[1] See Sheet E.3 for riprap details.

LC

Slope 14.14%

Sta 702+39.7, Offset 12.15' RT

5' typ.

5'-0"5'-0" per detail Sheets E.6, E7 and E.8 fish rocks, and rock weirs Install sediment retention sills, weirs per detail Sheet E.6, E.7 and E.8 fish rocks, and rock

Install sediment retention sills, TYPICAL ELEVATION

DETAILS

RIPRAP END TREATMENT

BOX CULVERT

NO SCALE

SECTION A-A

E.3

STATE PROJECT

NUMBER

SHEET

I n t_ ft m y fi le s p w p r o d u c ti o n d w a e r l6 e c .d g n

WA FS ERFO 2016(1)-20(1)

D e c e m b e r

L e

N e ig h o

C h e c k e d b y

D e s ig n e d b y

A

A

Streambed material

Cut-off wall

Streambed material

RIPRAP END TREATMENT

Cut-off wall

Box culvert

Placed riprap, method B, class 3

WingwallBox CulvertWingwall

Placed riprap, method B, class 3 m in m in geotextile, class 1, type C

Separation and stabilization geotextile, class 1, type C

Separation and stabilization

5' min.

m in

NOTE:

2.

1.

beneath and at all side of placed riprap.

Place earthwork geotextile between riprap and existing, Separation and stabilization geotextile is subidiary to 251.

Finish grade at face of wall

GENERAL NOTES:

Factored bearing resistance: 1 ton/sq. ft.

Unit weight: 125 lbs/cu. ft.

SOIL:

of any bar shall be 2-inches.

(ASTM, A615) grade 60. The minimum concrete cover to the face

All reinforcing steel shall conform to AASHTO M31, deformed

REINFORCING STEEL:

-inch.4 3Chamfer all exposed edges with minimum 28-day design compressive strength f'c=4000 psi.

All concrete shall be structural concrete, class A(AE)

CONCRETE:

HL-93.

LIVE LOAD:

Concrete: 150 lb per cubic foot.

DEAD LOAD:

drawings for review by the CO. See section 104.

dimensions, lines, and grades shown in the plans and provide shop wingwalls, and cut-off walls conforming to ASTM-C1577 and to the

Contractor shall provide precast concrete box culvert, headwalls, FP-14 (U.S. Customary).

Construction of Roads and Bridges on Federal Highway Projects, Federal Highway Administration Standard Specifications for

Detail is for general information only.

CONSTRUCTION:

PLAN

Box invert

Bottom of Box

Top headwall

Box crown

CONNECTION PLATE DETAIL

Bottom of Cutt-off Wall

SHEET 1 of 2

STRUCTURE DETAILS

BOX CULVERT

NO SCALE

SECTION A-A SECTION B-B

P

D e c e m b e r

L e

N e ig h o

C h e c k e d b y

D e s ig n e d b y

STATE PROJECT

NUMBER

SHEET

WA ERFO 2016(1)-20(1) E.4

I n t_ ft m y fi le s p w p r o d u c ti o n d w a e r l6 e d .d g n plate assembly

Welded connection

24"24"6'-0"6'-0"

BOX CULVERT

12" depth

Bedding material, (per manufacturer)

Wire mesh along both sides (typ.)

" Bevel2 1" x 22

12 along both sides

" Bevel2 1" x 22 culvert concrete

Precast wingwall concrete

Precast and wingwall joint wrap along culvert

Grout and mastic

10" min.

10" min. base slab sections (typ.)

manufacturer between precast

Install tie rods or connector plates per

Install tie rods or connector plates per manufacturer between precast sections (typ.)

Weep holes per manufacturer

12" depth material, Bedding install connector plates per manufacturer along culvert and wingwall joint (typ.), and

Water tight grout and mastic wrap

A

A

B B plates (typ.)

connection

Embedded

Headed stud ty p

30"-0"

(4' min.)

spacing per manufacturer Watertight box joint

NOTE:

SECTION PROFILE

SHEET 2 of 2

STRUCTURE DETAILS

BOX CULVERT

NO SCALE

1.

2.

3.

D e c e m b e r

L e

N e ig h o

C h e c k e d b y

D e s ig n e d b y

STATE PROJECT

NUMBER

SHEET

WA ERFO 2016(1)-20(1) E.5

I n t_ ft m y fi le s p w p r o d u c ti o n d w a e r l6 e e .d g n

BOX CULVERT BEDDING DETAIL

10"

15°

WATERTIGHT BOX JOINT SECTION

foam gasket Closed cell

DETAIL

HEADWALL AND CUTOFF WALL

Headwall (per precast culvert manufacturer)

Headwall (per precast culvert manufacturer) precast culvert manufacturer)

Cutoff wall (per

1.5 inches or greater than 2.0-inches.

concrete cover over the reinforcing steel shall not be less than reinforcing meeting the requirements of AASHTO LRFD Section 5.

Reinforcing for headwall and cutoff walls shall be welded wire recommendations.

Dowels shall be installed in accordance with the manufacturers

Fill dowel holes with polymer grout.

V a r ie s

2'-6" max.

Span + 4'

Bedding material

R is e

Span Thickness in 6" lifts

Soil compacted

Bedding material, 12" depth

Cutoff wall (per precast culvert manufacturer)

"2 14"8 ref.

rope

" mastic 4

" gap2

Non-shrink grout

"4 14 " ref.8 top and sides only

(outside joint) on mastic joint wrap

Grout and 9" wide

Inside face of box culvert box culvert

Outside face of

10" spaced 2'-6" max.

3" dia. holes with No. 8 dowels spaced 2'-6" max.

3" dia. holes with No. 8 dowels spaced 2'-6" max.

3" dia. holes with No. 8 dowels spaced 2'-6" max.

3" dia. holes with No. 8 dowels

18' Span

R is e

R is e

TREATMENT

STREAM CULVERT

SIMULATED

LOCATION

(FT)

X

(CUYD)

COBBLE

STREAMBED

(CUYD)

SEDIMENT

STREAMBED

(CUYD)

STONE

BANK

GRADATION

COBBLE

STREAMBED

(FT)

W

MITIGATION

FISH PASSAGE BOULDER

(IN)

DIA. NO.

FSR1050 MP 1.7 10 14.5

[4]STREAMBED MATERIAL

TOTAL

E 98 9 10145

E.6

STATE PROJECT

NUMBER

SHEET

I n t_ ft m y fi le s p w p r o d u c ti o n d w a e r l6 e f.

d g n

WA FS ERFO 2016(1)-20(1)

D e c e m b e r

L e

N e ig h o

C h e c k e d b y

D e s ig n e d b y

: SECTION A-A

PLAN

NOTE:

FOOTNOTE:

W

Streambed sediment

Streambed cobble

Box culvert wall

Channel flowline

Streambed sediment Streambed top

Culvert wall

LC

Flow

BB

A

W

X (typ.)

where specified on plan per detail Sheet E.7

Sediment retention sill specified on plan boulder where

Fish passage where specified on plan per detail Sheet E.7

Sediment retention sill specified on plan boulder where

Fish passage

NO SCALE

Streambed Material.

Infill informational quantities are incidental to ITEM 64704-1000 [4] dimension.

smallest 4 3 Embed fish passage boulders within active channel [3] sediment where listed in the infill quantities table.

Construct well defined banks with bank stone and streambed[2] parabolic shape.

Slope streambed aggregate towards flowline to ensure[1]

[1]Channel flowline

B u ri a l d e p th

[2]Bank stone

[2]Bank stone

AFlow

SECTION B-B

(typ.)

36" min.

Streambed cobble

Culvert outlet

Streambed sediment plan sheet or Length on

4'

LC

specified on plan

Sheet E.8 where

Rock weir per detail outlet

Culvert streambed cobble, and bank stone gradations.

See special contract requirements for streambed sediment, Mix streambed cobbles evenly throughout streambed sediment.

2.

1.

specified on plan boulder where

Fish passage

X (typ.)

on plan where specified detail Sheet E.8

Rock weir per where specified on plan per detail Sheet E.7

Sediment retention sill

[3] specified on plan matching rock weir spacing where

Fish passage boulder each side

DETAILS

SEDIMENT RETENTION SILL

CULVERT

LOCATION (IN)

B

(IN)

H

(NO.)

Min.

SRS

(IN)

Max.

X

MITIGATION

SEDIMENT RETENTION SILLS (SRS)

FSR 1050 MP 1.7

E.7

STATE PROJECT

NUMBER

SHEET

I n t_ ft m y fi le s p w p r o d u c ti o n d w a e r l6 e g .d g n

WA FS ERFO 2016(1)-20(1)

N o v e m b e r

L e

N e ig h o

C h e c k e d b y

D e s ig n e d b y

3 18 8 10

NOTE:

NO SCALE

B

H

CROSS-SECTION

PRECAST BOX CULVERT

SEDIMENT RETENTION SILLS

LC

DETAIL

CONCRETE SILL

X

Flow retention sill

Top of sediment

2 - #5

12"

1 row alternate sides

2 - #5

1" threaded inserts (typ.)

#5 @ 1'-6" with inserts (typ.)

1" threaded

1" threaded inserts (typ.)

c l.

2" cl.

D

V a r ie s

D locating SRS away from seems.

X dimension may be varied +/- 6-inches as needed for1.

(in)

DIAMETER

FOOTER ROCK

TOP ROCK AND

(no.)

QUANTITY

ROCK WEIR

MITIGATION

ROCK WEIR

(ft)

B

(ft)

Z

(ft)

W

LOCATION

DETAIL

ROCK WEIR

FSR 1050 MP 1.7 (INSIDE CULVERT)

FSR 1050 MP 1.7 (OUTSIDE CULVERT)

E.8

STATE PROJECT

NUMBER

SHEET

I n t_ ft m y fi le s p w p r o d u c ti o n d w a e r l6 e h .d g n

WA FS ERFO 2016(1)-20(1)

N o v e m b e r

L e

N e ig h o

C h e c k e d b y

D e s ig n e d b y

14.5 1.75 [5]0 3

14.5 28 4

Flow

F lo wA

A

ELEVATION

PLAN

SECTION A-A

NO SCALE

FOOTNOTE:

Align footer rocks flush against bed retention sills inside culvert. [5] and stable foundation for the top rocks.

Place footer rocks close together to create a tightly packed[4] streambed material.

Fill voids in top rock and footer rock with specified[3]

Space top rocks in center 1/3 only.[2]

Orient top rocks to deflect water towards center of stream.[1]

[4] [3]Footer rock

Z

D o w n s tr e a m f r o m c o n tr o l)

Top rock

Bottom of channel

Bottom of channel

[4] [3]Footer rock high water level

Ordinary normal low flow

Edge of water

Control point

[2] [1] [2] [1]

[2]

[3] [2]Top rock

[2]

[2] [2] [2]

[2] streambed material elevation or top of

Original streambed

[4] [3]Footer rock

[3]Top rock water level

Ordinary high

BWB

W3

B W3 1 W 3

B

W3

Appendix E – Special Contract Requirements (SCRs)

Section 647. — ENVIRONMENTAL MITIGATION (ADDED SECTION)

08/01/14–FP14

Description

647.01 This work consists of furnishing and placing streambed material, placing conserved streambed material, placing fish passage boulder, constructing rock weirs, placing logs with root wads, and reconstructing streambed channels.

Material

647.02 Conform to the following Subsections:

Furnished streambed material 703.18 Riprap 705.02 Fish Passage boulder 705.08 Root Wad 713.18

Construction Requirements

647.03 General. Construct erosion control measures according to Section 157.

Minimize damage to roots and trunks during construction.

Minimize construction disturbance around streams.

Conserve topsoil according to Section 204.

Excavate according to Section 209.

647.04 Stream Channel. Shape constructed channels to blend with natural streambed channels or to the contours shown in the plans.

647.05 Streambed Material. Streambed material is defined as streambed sediments and streambed cobbles (class A, B, C, D, or E). Conserve streambed material meeting requirements of Section 703.20 and stockpile in locations approved by the CO. Conserve and stockpile material to prevent segregation. If sufficient conserved streambed material is not available, furnish streambed material. Mix furnished streambed cobbles with streambed sediment to provide a uniform mixture. Place streambed material in lifts not exceeding 12 inches. Avoid displacing underlying material. Do not place material by methods that cause material segregation or damage to the culvert wall. Place the streambed material to form a well-graded, compacted, low-permeability mass. Compact each layer by making at least three passes with a vibratory plate compactor, each pass completely covering the placed layer surface. Construct a well-defined parabolic shape by sloping streambed materials placed inside culverts towards the culvert flow line. Shape the top layer so it is similar in appearance and texture to the natural streambed.

647.06 Fish Passage Boulder. Place fish passage boulder at locations shown on the plans. Bury stone to ¾ depth in the smallest dimension.

647.07 Bank Stone. Place streambed cobbles meeting the gradation of Class E Streambed Cobbles to form banks along the culvert walls as shown on the plans. Place cobbles close together and fill voids with streambed sediment to form a compact, low-permeability mass.

Extend bank stone upstream and downstream of culvert as needed for smoothly and uniformly transitioning to the natural, undisturbed stream banks.

647.08 Rock Weirs. Place stone meeting requirements of Section 705.07 in a well-defined parabolic shaped weir pointing upstream. Place stones close together to form a compact and rigid mass. Ensure the rock weir legs slope up from a lower apex in the center of the channel to the terminations in the overbank area. Fill the voids in the rock weir and backfill the excavation with streambed material.

647.09 Footer Logs and Logs with Root Wads. Install footer logs and logs with root wads as shown on the Plans and approved by the Engineer.

Excavate the bank to accommodate the root wad trunk which will be embedded into the bank.

Excavate according to Section 209. The excavation shall be slightly deeper further inland from the edge of the watercourse. The Engineer shall review and approve the subgrade lines and grades created during construction.

Install footer logs so that they sit parallel to the bank. Set footer log elevations such that, when the logs with root wads are placed on top, one third of the root fan diameter will be submerged below the normal water level.

Set root wad trunks so that the trunks in the excavation rest on the footer log. Slightly angle the root wad trunks so that the root wad structure is facing upstream at the angle specified on the plans.

Embankment and riprap shall be placed concurrent with footer logs and logs with root wads in accordance with Sections 204 and 251. Soils salvaged from onsite excavation may be utilized within embankment as approved by the Engineer.

647.10 Acceptance. Material and construction will be evaluated under 106.02.

Measurement

647.11 Measure the Section 647 items listed in the bid schedule according to Subsection 109.02.

Payment

647.12 The accepted quantities will be paid at the contract price per unit of measurement for the Section 647 pay items listed in the bid schedule. Payment will be full compensation for the work prescribed in this Section. See Subsection 109.05.

Section 703. — AGGREGATE

703.18 Furnished Streambed Material. (Added Subsection).

Streambed material consists of a mix of furnished streambed cobbles (class A, B, C, D, or E) with streambed sediment to provide a uniform mixture. Furnish material consisting of hard, durable, free from seams, cracks, and other defects conforming to the following:

(a) Accelerated weathering of aggregate by use of Dimethyl 12% max. loss Sulfoxide (DMSO), WFLHD Standard Test Method

(b) Apparent specific gravity, AASHTO T 85 2.55 min.

(c) Los Angles abrasion, AASHTO T 96 50% max.

(d) Gradation, Streambed Sediment. Furnish material meeting the gradation requirements of Table 703-13. Where possible and approved by the Engineer, conserve round or sub-round material from the culvert and roadway excavation meeting the requirements of Table 703-13 to use as streambed sediment.

Table 703-13

Streambed Sediment Gradation

Sieve Size

Percent by Weight Passing Designated Sieve

(AASHTO T 27 and T 11)

2 ½ inch 100

2 inch 75 – 100

1 inch 50 – 85

No. 4(1) 30 – 50

No. 40 25 max.

No. 200 5 – 15

(1) No more than 0.2 percent woody debris retained.

(e) Gradation, Streambed Cobbles. Furnish material meeting the requirements of Table 703-

14. Where possible and approved by the Engineer, conserve round or sub-round material from the roadway excavation meeting the requirements of Table 703-14 to use as streambed cobbles.

Table 703-14 Streambed Cobbles Gradation(1)

Nominal Size

Percent less than the nominal size Class

A B C D E 12" 100 10" 100 8" 100 65-75 6" 100 65-75 5" 65-75 35-45 4" 100 65-75 35-45 3" 35-45 2" 35-45

1 ½" 35-45 ¾" 10-15 10-15 10-15 10-15 10-15

(1) Grading of the cobbles will be by visual inspection of material before it is placed, and if directed by the CO, by placing material on a flat surface and sorting and measuring a sampling of the cobbles..

Note: Approximate size can be determined by taking the average dimension of the three axes of the rock; length, width, and thickness by use of the following calculation:

Size eApproximat

Thickness Width Length

Section 705. — ROCK

705.08 Fish Passage Boulder and Weir Stone. (Added Subsection).

Furnish hard, durable stone, free from seams, cracks, and other defects, conforming to the following:

(a) Apparent specific gravity, AASHTO T 85 2.50 min.

(b) Absorption, AASHTO T 85 4.2% max.

(c) Coarse durability index, AASHTO T 210 50 min.

(d) Gradation. Furnish round to angular stone meeting the approximate size shown in the plans.

Sizing of the stones will be by visual inspection of material before it is placed, and if directed by the CO, by placing material on a flat surface and sorting and measuring a sampling of the stones.

Approximate size can be determined by taking the average dimension of the three axes of the rock; length, width, and thickness by use of the following calculation:

Size eApproximat

Thickness Width Length

Do not use shale, rock with shale seams, or other fissured rock that may break into smaller pieces.