63-mp17-2_Sky_AOP_Hydraulics_Memo_combined-1.pdf

Memorandum

Western Federal Lands Highway Division 610 E. Fifth Street

Vancouver, WA 98661-3801

MT. BAKER FISH PASSAGE IMPROVEMENTS

FSR 63 MP 17.2 AOP HYDRAULICS REPORT

To: Matthew Miller, WFLHD Project Manager From: Sven Leon, P.E., WFLHD Hydraulics Engineer Date: February 15, 2018 Project: Skykomish ERFO – WA EFRO 2016(1)-20(2)

Background

The Forest Service (FS) is replacing a failed culvert on forest service road (FSR) 63 at mile post (MP) 17.2, Mt. Baker National Forest, Snohomish County, Washington (Fig. 1). The Forest Service will maintain the new structure. Western Federal Lands Highway Division (WFLHD) is designing the replacement structure. Recommendations for the proposed aquatic organism passage (AOP) structure design are presented.

AOP Design Criteria

Forest Service biologists confirmed FSR 63 MP 17.2 crossing requires an AOP structure (47.9134/- 121.3133, NAD1983). The crossing is located on an unnamed tributary to the North Fork Skykomish River. This unnamed tributary provides rearing habitat for steelhead trout and bull trout, federally listed Endangered Species Act (ESA) anadromous fish species. Cutthroat trout may be present. 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 like the adjacent channel, providing similar channel complexity, flow depth, flow velocities, and resting areas.

The following requirements have been incorporated 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

Memo to: Matthew Miller, WFLHD Project Manager February 15, 2018 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 63 MP 17.2 AOP Culvert

The stream at this crossing location is a tributary to the North Fork Skykomish River. The stream crossed Forest Road 63 through an existing 9-foot wide by 6-foot high pipe arch culvert which is located approximately 0.1 miles northwest from the confluence with the North Fork Skykomish River. Heavy rains during the winter of 2016 resulted in a landslide approximately 0.35 miles upstream of the crossing (Fig. 2). The landslide sent a large amount of sediment and debris into the stream channel. High flows carried the slide material downstream causing the channel to aggrade and avulse depositing material across 40 to 80 feet of the drainage bottom. The existing culvert inlet was completely plugged by deposited material and wood debris. Flows overtopped the road and washed out the embankment north of the culvert. Further aggradation 0.1 miles upstream rediverted the stream into a new drainage to the north. The stream has carved a new channel and now crosses the road 150 feet north of the existing culvert. There is potential for the stream to return to its original channel if another large flood event occurs.

Upstream and downstream of the new crossing, the stream has deposited material across an area 40 to 80 feet wide along the drainage bottom. Portions of the newly eroded banks outside of this zone upstream of the crossing are vertical, highly erodible, and unstable.

Approximately 75 feet downstream of the new crossing, the stream flows over a series of logs buried within the deposited material. This has formed a nick-point and 7-foot drop in the channel bed. There is a likely potential for the stream to erode around or under the logs. This could allow the nick-point and channel degradation to migrate upstream to the culvert crossing over time.

Due to the excessive amount of recent deposition across the valley floor, streambanks are poorly defined.

The stream is in the process of downcutting and forming a single low flow channel. Very little references remain for accurate measurements of bankfull widths. Measurements to estimate bankfull width were taken upstream at locations where the new stream alignment appeared to be confined to a single channel during the flood event (see Appendix, photos 7). Measurements suggest that the natural bankfull width may range between 16 to 18 feet, or less, with a channel slope around 15 and 18 percent. The channel depth is 18 to 24 inches. Step pool and cascade is the dominant bed form. Boulder, cobble, and gravel is the dominant bed material. Streambed gradation was measured by digital pebble count using FHWA Hydraulic Toolbox, version 4.2, and processing digital-scaled photograph at a stream location. Resulting gradation is D100 19.6 inches, D85 14.6 inches, D50 6.4 inches, and D15 2.4 inches (Fig. 3).

Based on observed post flood conditions, the stream can likely carry a large amount of small to moderate sized woody debris. Stream flow when fish passage is needed will be low. Smaller flows could submerge within the natural channel where larger loose material has been deposited. To avoid creation of similar low flow subsurface conditions, material placed within the proposed culvert and outlet will need to avoid excessive amounts of oversized loose bed material or large stone. Continued aggradation should be expected as the new stream channel erodes, reforms its natural bankfull channel, and transports material from upstream. Additional debris flows during large flood events can be expected due to the remaining unstable slopes and large amount of unvegetated loose deposited material remaining upstream from the site.

Recommendations:

Install new culvert on existing culvert alignment.

Install a 20-foot long, precast concrete box culvert with 20-foot span and 16-foot rise (Sheet D.3).

To maximize capacity for flow and debris conveyance and accommodate channel aggradation, set culvert crown as high in the road prism as possible (elevation 3034.7 feet, project datum).

Place culvert floor at elevation 3018.7 feet (project datum).

Maximizing clearance for debris passage and maintenance access by installing culvert flat.

Place conserved streambed material inside the culvert matching the gradation of the natural streambed material upstream.

Slope the channel surface to match upstream gradient (16 percent).

Construct a defined flow channel 13 feet wide at the bottom and 18 inches deep (Sheet D.4).

Construct the flow channel banks from coarser gravel, gobble, and boulder material.

Install nine boulders, approximately 30 inches in diameter, as shown on Sheet C.5 for inducing channel migration and providing low velocity fish resting areas.

Install 16 feet long precast concrete headwalls at the culvert inlet (bottom elevation 3017.7 feet, project datum) (Sheets D.4 and C.7).

Install 24 feet long precast concrete headwalls at the culvert outlet (bottom elevation 3014.7 feet, project datum).

Angle the wingwalls 45 degrees to the culvert centerline.

Install Class 3 riprap (FHWA FP-14), minimum 3 feet thick, at the inlet and outlet for controlling road embankment erosion near the headwalls (Sheets D.4 and C.6).

Install Class 1-C nonwoven geotextile (FHWA FP-14) under the riprap.

Shape new channel approximately 105 lineal feet immediately upstream and 100 lineal feet immediately downstream for aligning the culvert channel with the natural channel.

Remove debris from channel 105 feet upstream of inlet and 100 feet downstream of outlet (Sheet D.3).

Seed and plant any disturbed areas with local native vegetation.

Raise road profile 3 feet for accommodating proposed culvert design.

Construction

Work within the ordinary-high-water limits can only be performed between August 1 and February 28.

Temporary flow deflectors placed for isolating the work area and diverting the stream flow must have a minimum height of 3 feet above the stream bottom and be stable assuming 8 feet per second parallel flow and 2 feet maximum water depth. Use plastic-lined channels or pipes for temporally conveying stream flow through the construction area. Protect the outfalls from erosion. Fish passage downstream through the temporary flow diversions is required. Ensure fish can pass smoothly from the upstream diversion point to the downstream diversion point. Locate diversion points in the main stream channel. Fish passage upstream is not required. Assuming in-stream construction occurs August 1 to October 15, temporary flow diversions must have a minimum flow capacity equal to 40 cubic feet per second (cfs).

Temporary stream diversions in place October 16 through February 28 must have minimum flow capacity equal to the 2-year discharge (121 cfs). Before installing the flow deflectors, remove fish from the work area to the level and methods specified in the environmental permits.

Vehicular traffic will not be maintained through the work site. Full construction area dewatering is expected up to the groundwater level for excavation and installing the culvert, streambed material, backfill, and riprap. Water pumped from work area must be discharged at an upland area near the site.

Access for culvert installation work can be accomplished within the existing road embankment footprint.

Temporary access route adjacent to the road embankment is needed for installing flow barriers, removing the channel debris, and completing culvert inlet, interior, and outlet work. Constructing the proposed culvert and in-stream work may require heavy track-mounted equipment operating on the stream bed, possibly in water up to 2 feet deep.

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 for adjacent natural streams. Both channel incision and aggradation is expected upstream, inside, and downstream of the proposed fish passage culvert.

A moderate amount of turbidity and sediment is expected to be released 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 introducing the stream flow over an extended two to three-hour time.

Operation and Maintenance

Woody debris will tend to accumulate more frequently at the culvert inlet and inside the culvert barrel.

The FS should increase the frequency of culvert inspection and woody debris removal. Stream degradation is not expected to negatively impact culvert structure or performance. Stream aggradation could reduce the culvert hydraulic capacity. Remove sediment from the upstream channel, inside the culvert, the downstream channel when there is less than 5 feet of clearance between the stream bottom and culvert crown at the inlet. Riprap placed at the culvert inlet and outlet should be inspected annually and after each extreme flood event. Replace or reposition dislodged stone.

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.

Hydrology

The USGS StreamStats (version 4) web-based application was used for delineating the watershed and calculating drainage area (0.58 sq. miles), mean basin elevation (3580 feet), canopy cover (75.7 percent), and mean annual precipitation (162 inches). Peak discharges were estimated with StreamStats using USGS regression equations from Magnitude and Frequency of Floods in Washington (USGS WRIR 97- 4277). Watershed is entirely within Region 2 for the USGS regression equations. The watershed is mostly heavily forested (Fig. 2). Small areas of bedrock and talus are found at the higher elevations.

Talus fields can contribute sediment to the stream channel. Clear-cut logging has occurred and can occur in the future. No flow diversions or lakes occur. The drainage area is steeply mountainous with moderately incised drainages. Area with slopes greater than 30 percent is 93.7 percent. Elevations range from 1880 to 5130 feet (NAD83/WGS84). Peak discharges estimates are presented in Table 1.

Dominant flooding is from snow melt. Larger floods typically occur in April, May, and June. Rain-on-snow flood events occur in October, November, and December. Lowest flows occur in July, August, and September.

Culvert Hydraulics

Water surface profiles and culvert capacities were estimated using the FHWA Culvert Hydraulics Analysis Program, HY-8, version 7.5 (results attached). Floods larger than the 2-year were analyzed assuming culvert slope of 15 percent and Manning’s Roughness coefficient of 0.098. Headwater depths are shown on Table 1.

Flow depths and average channel velocities inside the proposed culverts for up to the 2-year peak discharge were estimated with the FHWA Hydraulic Toolbox, version 4.2, open-channel flow calculator.

The calculations assumed 13 feet channel bottom width, 1:1 sides, and 16 percent channel slope. The Manning’s Roughness coefficient was iterated until a Froude number of 1.0 was achieved for the 2-year discharge. This represents the minimum energy for the stream and the channel inside the culvert and models the turbulent nature of natural steep-gradient, cobble-bedded streams. A Manning’s Roughness coefficient of 0.098 was selected. Average channel flow velocities inside the culverts are presented in Figure 4.

attachments: Table 1 Figures 1, 2, 3, and 4 Photographs 1 to 9 Drawings D.3, D.4, C.5, C.6, and C.7 Peak Discharge Estimates HY-8 Calculations Hydraulic Toolbox Calculations Channel Profile

Drainage

Site Area (mi2) 2 5 10 25 50 100 500

Culvert Peak Q (cfs) 0.58 121 NA 237 301 363 413 565

Water Elev. at Inlet (ft) 3,030.1 NA 3,030.9 3,031.2 3,031.6 3,031.9 NA

Clearance at Inlet (ft) 4.6 NA 3.8 3.5 3.1 2.8 NA

Water Depth at Inlet (ft) 1.1 NA 2.2 2.5 2.9 3.2 NA

Notes:

1. USGS - USGS Regression Equations, “Magnitude and Frequency of Floods in Washington”, WRIR 97-4277, 1998.

NA = Not analyzed.

Table 1. Peak Discharges (ft3/sec) and Water Depths at Inlets

Recurrence Intervals (years)

Image date: 7/23/2017

Project AOP Culvert Site Location

Project Area Location

Map printed from National Geographic TOPO

MP 16.6

N

N o rt h

F o rk S ky ko m is h R iv er

FIGURE 1

FSR 63 MP 17.2 - AOP CULVERT

SITE LOCATION

MP 17.2

1000 feet0

Map printed from Google Earth, Image date 7/23/2017.

MP 16.6

N

DA = 0.5 sq. mi.

FIGURE 2

FSR 63 MP 17.2 - AOP CULVERT

DRAINAGE AREA

MP 17.2

0 2000 feet

DA = 0.58 sq. mi.

FIGURE 3

FSR 63 MP 17.2 - AOP CULVERT

STREAMBED GRADATION

FIGURE 4

FSR 63 MP 17.2 - AOP CULVERT

2-YEAR FLOW VELOCITY

Photos

PHOTO 1

PHOTO 2

PHOTO 3

2/14/2018

FSR 6300 MP 17.2

Culvert completely plugged with debris.

The inlet is crushed.

A landslide 0.35 miles upstream sent debris downstream. Debris deposited

0.1 miles from the culvert crossing diverted flow into a separate drainage.

The stream no longer flows within original drainage and now crosses the road 150 feet to the north.

Culvert interior.

Culvert Inlet looking east toward the outlet.

Inlet completely burried with debris and roadway washed out. No flow within the old channel.

Roadway washed out at origainal crossing location.

PHOTO 4

PHOTO 5

PHOTO 6

2/14/2018

FSR 6300 MP 17.2

Material and logs deposited east of the road. Channel banks not well defined.

New location of drainage channel at road crossing.

The stream has shifted to a new channel 150 feet north of the existing culvert.

Channel upstream of the new road crossing.

Material and debris deposited from the upsteam landslide across the new drainageway approximately 40 to 80 feet wide.

Channel downstream of the new road crossing.

PHOTO 7

PHOTO 8

PHOTO 9

2/14/2018

FSR 6300 MP 17.2

Series of logs imbedded in the deposited material form a nick-point and 7-foot drop in the channel bed downstream of the new road crossing.

Upstream channel diversion point.

The stream was diverted approximately

0.35 miles west of the road. Aggradation in the old channel forced the stream into a new drainageway to the north.

Bankfull width measured upstream of the new stream crossing.

Logs 125 feet downstream of new crossing.

Due to excessive deposition across the new drainage, there are very few features available to reference for accurate measurements of bankfull widths. An estimate for bankfull width was estimated where the channel appeared to be confined to a single channel during the flood event. A bankfull width of 16 to 18 feet was estimated for a channel reach with an approximate slope of 15% to 18%.

0 10 20 30 40 50 60 7060 50 40 30 20 1070

8090100110120130140150 80 90 100 110 120 130 140 150

Flow

N

PIPE INLET OUTLET

FISH SPECIES:

INSTREAM WORK WINDOW: 7/1- 9/15

ACTIVE CHANNEL WIDTH: 16 feet

LENGTH: 20 feet

INFILL TYPE: SBM

SPAN: 20'-0"

FLOWLINE SLOPE: 0.16 ft/ft

TYPE: Conserved

INV N/E/EL: 3018.7 INV N/E/EL: 3018.7

HYDRAULIC INFORMATION

100 100

OHW : 1.5 feet

HW : 3.5 feetQ : 413 cfs

PIPE SLOPE: 0.0 ft/ft

RISE: 16'-0"

SCALE IN FEET

0 1010 20 25

PLAN & PROFILE

AOP CULVERT

FSR 63 MP 17.2Q : 121 cfs TYPE: Concrete Box Culvert

WALL THICKNESS: 12 in

BEVEL: None BEVEL: None

LOWER BEVEL HEIGHT: None LOWER BEVEL HEIGHT: None

HEADWALL: Precast Concrete HEADWALL: Precast Concrete

BURIAL DEPTH: 9 feet BURIAL DEPTH: 6 feet

D.3

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 f1 d c .d g n

WA FS ERFO 2016(1)-20(2)

A

M

F e b r u a r y

C h e c k e d b y

D e s ig n e d b y S v e n L e o n

LC

locate as needed

Temporary flow barrier, Flowline

Elev 3036.7'

(L=20') concrete box culvert

New 20' x 16' precast

0.16 Ft/Ft

Elev 3017.7' transition to existing stream channel shape and locate for smooth

New stream channel CL, 105 L.F., LC

LC

locate as needed

Temporary flow barrier, grade contour

Existing

Placed riprap, class 3

Existing road

New culvert

Placed riprap, class 3

(L-20') concrete box culvert

New 20' x 16' precast

Elev 3036.7'

Elev 3024.7'

Elev 3028.7'

(L-24')New precast wingwall transition to existing stream channel shape and locate for smooth

New stream channel CL, 100 L.F., New precast wingwall (L-16') locate as needed

Temporary flow barrier, Station 24+22.0

Existing stream bottom

0.14 Ft/Ft

0.18 Ft/Ft

135°

'-0

'-0

100-yr WS profile

10'-0"

20' x 105' x 3'

Remove channel debris, New stream channel FL, 105 L.F.

elev 3035.7'

Existing road, New precast wingwall (L-16')

New precast wingwall (L-24')

Elev 3014.7'

New channel bottom edge Existing channel edge

Existing channel edge

New channel bottom edge

20' x 100' x 4'

Remove channel debris, from channel

Remove existing log

20' x 100' x 4'

Remove channel debris, New stream channel FL, 100 L.F.

debris, 20' x 105' x 3'

Remove channel stream bottom

Match existing materialstreambed

Conserved barrier, locate as needed

Temporary flow log from channel

Remove existing

ELEVATIONS

AOP CULVERT

FSR 63 MP 17.2

D.4

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 f1 d d .d g n

WA FS ERFO 2016(1)-20(2)

F e b r u a r y

C h e c k e d b y

D e s ig n e d b y S v e n L e o n

CULVERT INLET

CULVERT OUTLET

TYPICAL CULVERT CHANNEL

Placed riprap, class 3 concrete box culvert

New 20' x 16' precast Flowline

Elev 3035.7'

Existing grade, upstream

2-yr WS

Floor elev 3018.7' Elev 3017.7'

TOW, elev 3036.7'

Elev 3028.7'

100-yr WS

Raise existing road surface 3.0' transition to existing stream channel shape and locate for smooth

New stream channel surface, Placed riprap, class 3 concrete box culvert

New 20' x 16' precast Flowline

Elev 3035.7'

2-yr WS

Floor elev 3018.7' Elev 3014.7'

TOW, elev 3036.7'

Elev 3024.7'

100-yr WS

Raise existing road surface 3.0' transition to existing stream channel shape and locate for smooth

New stream channel surface, New precast wingwall (L-16')

New precast wingwall (L-24')

Existing grade, downstream

5'-0"

5'-0"

Channel bottom edge

Channel bottom edge

LC

LC

Precast concrete cutoff wall

13'-0"

16'-0"2'-0"

2'-0" materialstreambed

Conserved materialstreambed

Conserved

Not to scale.

NO SCALE

PLAN

Flow

A

A

BB

NOTE:

FOOTNOTE:

3.

2.

1.

Stagger in-channel fish passage boulder within the culvert span.

streambed cobble, and bank stone gradations.

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

[1]

[4]

Material.

Quantities included in Item 64704-1000 Mitigation, Streambed[4] dimension.

smallest4 3 Embed fish passage boulders within active channel [3] sediment.

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

Slope streambed aggregate towards flowline to ensure[1]

LOCATION

(ft)

D

(ft)

W

(in)

GRADATION

COBBLE

STREAMBED

INFILL INFORMATIONAL QUANTITIES

(cuyd)

COBBLE

STREAMBED

(cuyd)

SEDIMENT

STREAMBED

15 Class E 9 25

(cuyd)

STONE

BANK

20 30

(in +/- 4)

BOULDER DIAMETER

FISH PASSAGE

ITEM DESCRIPTION UNIT

each

64703-6000

64704-1000

QUANTITY

MITIGATION QUANTITIES

Fish passage boulder

Streambed material cuyd

90 180FSR 63 MP 16.6

360 18 50

(each)

BOULDER

FP

FSR 63 MP 17.2 20 16 Class E 90 180 30 9 25

INTERIOR TREATMENT

CULVERT

SIMULATED STREAM

C.5

STATE PROJECT

NUMBER

SHEET

U

S I n t2

D c m y fi le s p w p r o d u c ti o n d w a e f1 c e .d g n

WA FS ERFO 2016(1)-20(2)

P e b r u a r y

S v e n L e o n

C h e c k e d b y

D e s ig n e d b y

SECTION A-A

Flow

D2

SECTION B-B

L C

D

D (typ.)

D (typ.)4

(typ.)

(typ.)

36" min.

or Length on plan sheet

W

Streambed sediment

Streambed cobble

Channel flowline

Pipe arch culvert wall

Box culvert wall boulder

Fish passage boulder

Fish passage

[3]Fish passage boulder

[2]Bank stone

[2]Bank stone d e p th b u r ia l b u r ia l d e p th

Round pipe culvert wall

"top

Streambed

Channel flowline

Streambed sediment

Culvert wall

Culvert outlet

Culvert inlet

Streambed cobble sediment

Streambed

Varies

DETAILS

BOX CULVERT RIPRAP

Flow

ITEM NO. DESCRIPTION UNIT QUANTITY

25101-0300

20701-0200

Placed riprap, method A, class 3

Separation- stabilization geotextile, class 1, type C

CY

SQYD

RIPRAP QUANTITIES

C.6

STATE PROJECT

NUMBER

SHEET

U

S S u r ft m y fi le s p w p r o d u c ti o n d w a e f1 c f.

d g n

WA FS ERFO 2016(1)-20(2)

P e b r u a r y

C h e c k e d b y

D e s ig n e d b y

SECTION A-ATYPICAL CULVERT PLAN

Varies bank top Stream bank top Stream

Proposed road grade headwall Box culvert

Wingwall footing

Wingwall top

A

A outside face Wingwall

Wingwall inside faceWingwall inside face

Stream bank toe

Stream bank toe wall Box culvert

NOTE:

NO SCALE

5'-0"

5'-0"

'-0

"5 " 5

'-0

5'-0"

Geotextile, class 1, type C

Geotextile, class 1, type C

Placed riprap, class 3

Culvert & streamLC Culvert & streamLC

Placed riprap, class 3

Placed riprap, class 3 transition to existing bank top and toe.

1. Place conserved streambed material over riprap as needed for

" (min.)2 12'-6

1'-3" (min.)

ty p

STRUCTURAL DETAILS

BOX CULVERT

SECTION PROFILE

C.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 f1 c g .d g n

WA FS ERFO 2016(1)-20(2)

e b r u a r y

C h e c k e d b y

D e s ig n e d b y plate assembly

Welded connection

Headed Stud

GENERAL NOTES:

Varies

15°

Precast footing

O Ring if required over pipe joint

Do not install fastener m a x precast permitted when

Tapered holes

" (max.)2 12'-9

(ref.)

"8 11 "2 on top and sides

(outside joint) mastic joint wrap

Grout and 9" wide box culvert

Outside of box culvert

Inside of "2

14 " (ref.)8

Non-shrink grout

V a ri e s

" Gap2

1¼" Mastic rope foam gasket

Closed cell

1'-5" (max.)

WATERTIGHT BOX JOINT SECTION

CONNECTION PLATE DETAIL

SUPPLEMENTAL CONCRETE PIPE TIE

WINGWALL DETAIL

(per manufacturer) wire mesh (typ.)

" 24 16"x6"xW

Non-shrink grout 1¼" Mastic rope foam gasket

Closed cell for 1"Ø joint tie

"Ø Hole4

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

along both sides (typ.)

" Bevel2 1" x 22

Weep holes per manufacturer

12" depth material, Bedding

BOX CULVERT BEDDING DETAIL

Bedding material

R is e

Span Thickness in 6" lifts

Soil compacted

R is e

DETAIL

HEADWALL AND CUTOFF WALL

Headwall (per precast culvert manufacturer)

Span + 4' plates (typ.)

connection

Embedded

Cutoff wall (per precast culvert manufacturer) spaced 2'-6" max.

No. 8 dowels

3" dia. holes with

R is e

Span

P e r p la n

P e r p la n

10" spaced 2'-6" max.

No. 8 dowels

3" dia. holes with

10" culvert manufacturer)

Headwall (per precast culvert manufacturer)

Cutoff wall (per precast

12" depth Bedding material, Bearing capacity: 2 ton/sq. ft.

Unit weight: 125 lbs/cu. ft.

SOIL:

Provide 2-inch minimum concrete cover to the face of any bar.

ASTM A1064.

(ASTM, A615) grade 60, or welded wire reinforcing conforming to

Furnish reinforcing steel bars conforming to AASHTO M31, deformed

REINFORCING STEEL:

Chamfer all exposed edges 3/4-inch.

compressive strength f'c=5000 psi.

Furnish structural concrete, class A(AE) with minimum 28-day design

CONCRETE:

HL-93.

LIVE LOAD:

Soil: 125 lb per cubic foot.

Concrete: 150 lb per cubic foot.

DEAD LOAD:

latest edition.

accordance with AASHTO LRFD Bridge Design Specifications, Design cut -off walls, headwalls, wingwalls, and footings in

Design precast culverts in accordance with Section 602.

DESIGN:

precast sections.

Install tie rods or connector plates per manufacturer between

104.

plans and provide shop drawings for review by the CO. See section walls conforming ASTM-C1577 and to the and grades shown in the

Provide precast concrete culverts, headwalls, wingwalls, and cut-off

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:

Attachments

Peak Discharge Estimates

HY‐8 Calculations

Hydraulic Toolbox Calculations

Channel Profile

Flow Statistics Ungaged Site Report Date: Mon Aug 7, 2017 2:44:34 PM GMT-7 Study Area: Washington NAD 1983 Latitude: 47.9134 ( 47 54 48) NAD 1983 Longitude: -121.3133 (-121 18 48) Drainage Area: 0.58 mi2

Peak-Flow Basin Characteristics

100% Region 2 (0.58 mi2)

Parameter Value Regression Equation Valid Range Min Max

Drainage Area (square miles) 0.58 0.08 3020 Mean Annual Precipitation (inches) 162 23 170

Peak-Flow Statistics

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

Min Max PK2 121 cfs 56 1 PK10 237 cfs 53 1 PK25 301 cfs 53 2 PK50 363 cfs 53 2 PK100 413 cfs 54 3 PK500 565 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.

StreamStats Version 3.0

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2/12/2018 StreamStats https://streamstats.usgs.gov/ss/ 1/2

StreamStats Report

Basin Characteristics

Parameter Code Parameter Descript ion Value Unit

BSLDEM30M Mean basin slope computed from 30 m DEM 56 percent

CANOPY_PCT Percentage of drainage area covered by canopy as described in OK SIR 2009_5267

75.7 percent

DRNAREA Area that drains to a point on a stream 0.58 square miles

ELEV Mean Basin Elevat ion 3580 feet

ELEVMAX Maximum basin elevat ion 5130 feet

MINBELEV Minimum basin elevat ion 1880 feet

NFSL30 Nor th-Facing Slopes Greater Than 30 Percent 5.14

PRECIP Mean Annual Precipitat ion 162 inches

RELIEF Maximum - minimum elevat ion 3250 feet

SLOP30_30M Percent area with slopes greater than 30 percent from 30-meter DEM. 93.7 percent

Region ID: WA Workspace ID: WA20180212210104921000 Clicked Point (Latitude, Longitude): 47.91311, -121.31305 Time: 2018-02-12 13:01:21 -0800

HY-8 Culvert Analysis Report

Table 1 - Culvert Summary Table: 20 x 16 conc box

* Full Flow Headwater elevation is below inlet invert.

Straight Culvert

Inlet Elevation (invert): 3028.70 ft, Outlet Elevation (invert): 3025.70 ft

Culvert Length: 20.22 ft, Culvert Slope: 0.1500

Culvert Data Summary - 20 x 16 conc box

Barrel Shape: Concrete Box

Barrel Span: 20.00 ft

Barrel Rise: 6.00 ft

Barrel Material: Concrete

Embedment: 0.00 in

Barrel Manning's n: 0.0980

Culvert Type: Straight

Inlet Configuration: Square Edge (30-75º flare) Wingwall

Inlet Depression: None

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)

121.00 121.00 3030.10 1.400 0.0* 1-S2n 1.030 1.044 1.030 1.299 5.874 5.713

150.20 150.20 3030.32 1.617 0.0* 1-JS1t 1.179 1.205 1.479 1.479 5.077 6.162

179.40 179.40 3030.52 1.820 0.0* 1-JS1t 1.319 1.357 1.645 1.645 5.453 6.552

208.60 208.60 3030.71 2.013 0.0* 1-JS1t 1.451 1.501 1.800 1.800 5.795 6.899

237.80 237.80 3030.90 2.197 0.0* 1-JS1t 1.577 1.637 1.946 1.946 6.110 7.211

267.00 267.00 3031.07 2.373 0.0* 1-JS1t 1.698 1.769 2.085 2.085 6.403 7.495

296.20 296.20 3031.24 2.543 0.0* 1-JS1t 1.815 1.896 2.218 2.218 6.679 7.758

325.40 325.40 3031.41 2.708 0.0* 1-JS1t 1.927 2.018 2.345 2.345 6.939 8.001

354.60 354.60 3031.57 2.867 0.0* 1-JS1t 2.037 2.137 2.467 2.467 7.186 8.228

363.00 363.00 3031.61 2.912 0.0* 1-S2n 2.068 2.171 2.068 2.501 8.777 8.291

413.00 413.00 3031.90 3.204 0.297 1-S2n 2.248 2.366 2.248 2.700 9.186 8.643

Table 2 - Downstream Channel Rating Curve (Crossing: FSR 63 MP 17.2)

Tailwater Channel Data - FSR 63 MP 17.2

Tailwater Channel Option: Trapezoidal Channel

Bottom Width: 15.00 ft

Side Slope (H:V): 1.00 (_:1)

Channel Slope: 0.1200

Channel Manning's n: 0.0980

Channel Invert Elevation: 3025.70 ft

Roadway Data for Crossing: FSR 63 MP 17.2

Roadway Profile Shape: Constant Roadway Elevation

Crest Length: 200.00 ft

Crest Elevation: 3035.00 ft

Roadway Surface: Gravel

Roadway Top Width: 16.00 ft

Flow (cfs) Water Surface Elev (ft) Depth (ft) Velocity (ft/s) Shear (psf) Froude Number

121.00 3027.00 1.30 5.71 9.73 0.92

150.20 3027.18 1.48 6.16 11.08 0.93

179.40 3027.34 1.64 6.55 12.32 0.94

208.60 3027.50 1.80 6.90 13.48 0.95

237.80 3027.65 1.95 7.21 14.57 0.96

267.00 3027.78 2.08 7.50 15.61 0.97

296.20 3027.92 2.22 7.76 16.60 0.98

325.40 3028.04 2.34 8.00 17.56 0.98

354.60 3028.17 2.47 8.23 18.47 0.99

363.00 3028.20 2.50 8.29 18.73 0.99

413.00 3028.40 2.70 8.64 20.21 1.00

Hydraulic Analysis Report

Channel Analysis: Channel Analysis - FSR 63 MP 17.2 - Channel

Input Parameters

Channel Type: Trapezoidal

Side Slope 1 (Z1): 1.0000 ft/ft

Side Slope 2 (Z2): 1.0000 ft/ft

Channel Width: 13.0000 ft

Longitudinal Slope: 0.1600 ft/ft

Manning's n: 0.0980

Flow: 121.0000 cfs

Result Parameters

Depth: 1.2988 ft

Area of Flow: 18.5706 ft^2

Wetted Perimeter: 16.6734 ft

Hydraulic Radius: 1.1138 ft

Average Velocity: 6.5157 ft/s

Top Width: 15.5975 ft

Froude Number: 1.0523

Critical Depth: 1.3428 ft

Critical Velocity: 6.2827 ft/s

Critical Slope: 0.1431 ft/ft

Critical Top Width: 15.69 ft

Calculated Max Shear Stress: 12.9668 lb/ft^2

Calculated Avg Shear Stress: 11.1200 lb/ft^2

Existing Stream Channel Gradient

Road CL

1"=40'

2970.0000

2980.0000

2990.0000

3000.0000

3010.0000

3020.0000

3030.0000

3040.0000

3050.0000

3060.0000

3070.0000

3080.0000

3090.0000

3100.0000

0.0000 10.0000 20.0000 30.0000 40.0000 50.0000 60.0000 70.0000 80.0000 90.0000 100.0000 110.0000 120.0000 130.0000 140.0000 150.0000 160.0000 170.0000 180.0000 190.0000 200.0000 210.0000 220.0000 230.0000 240.0000 250.0000 260.0000 270.0000 280.0000 290.0000 300.0000 310.0000 318.7771 2970.0000

2980.0000

2990.0000

3000.0000

3010.0000

3020.0000

3030.0000

3040.0000

3050.0000

3060.0000

3070.0000

3080.0000

3090.0000

3100.0000

0.0000 10.0000 20.0000 30.0000 40.0000 50.0000 60.0000 70.0000 80.0000 90.0000 100.0000 110.0000 120.0000 130.0000 140.0000 150.0000 160.0000 170.0000 180.0000 190.0000 200.0000 210.0000 220.0000 230.0000235.0925