AK Unnamed Creek AOP Report Final.pdf
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This memorandum provides recommendations for an aquatic organism passage (AOP) culvert design project on Skilak Lake Road within the Kenai National Wildlife Refuge in Alaska. The proposed design calls for replacing an existing 60-inch diameter corrugated metal pipe with a 118-foot long, 9-foot diameter corrugated metal round culvert set at an 8.68% slope to match the stream channel. The new culvert would be embedded 3.6 feet and backfilled with conserved native streambed materials augmented with cobbles to provide a stable substrate. A 6.7-foot wide channel with 1-foot deep banks would be constructed inside the culvert along with sediment retention sills, rock weirs, and 15 large boulders for fish habitat. Hydraulic analyses indicate the design meets guidelines for conveying flows up to the 100-year flood while replicating natural stream conditions. Construction is scheduled during Alaska's instream work period from May 15 to July 15.
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Memorandum
Western Federal Lands Highway Division 610 E. Fifth Street
Vancouver, WA 98661-3801
SKILAK LAKE ROAD / UPPER SKILAK LAKE ROAD
UNNAMED CREEK AOP HYDRAULICS REPORT
To: Stacy Bluhm, WFLHD Project Manager
From: James Neighorn, P.E. and Vernon Bevan, WFLHD Hydraulics Engineer
Date: June 20, 2023
Project: Skilak Lake Road – AK FWS Kenai 1192(1)
Background
The Kenai National Wildlife Refuge (NWR) is proposing Aquatic Organism Passage improvements to culverts within the Kenai National Wildlife Refuge (KNWR) located on Skilak Lake Road and Upper
Skilak Lake Road. The purpose of the culvert improvements is to restore aquatic organism passage, protect visitor safety, preserve the KNWR roadway infrastructure, and ensure roadway drainage structures are of the latest design standards. As part of the project the NWR is replacing a culvert that carries an unnamed creek under Upper Skilak Lake Road as it flows towards the Kenai River. The Kenai NWR 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
The proposed AOP structure has been designed following the requirements Culvert Design Guidelines for
Ecological Function (U.S. Fish and Wildlife 2021) and per Stream Simulation: An Ecological Approach to
Providing Passage for Aquatic Organisms at Road-Stream Crossings (USDA-Forest Service 2008). These documents provide simplified design methodologies intended to mimic natural stream processes within the culvert. Sediment transport, debris conveyance and streambed morphology within the culvert should replicate these processes as they occur in the natural channel upstream and downstream of the culvert.
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 replicate the stream conditions upstream and downstream of the crossing. AOP culvert design utilizes streambed materials and sizes which occur in the natural channel, providing similar channel complexity, flow depth, flow velocities, and resting areas.
USFW Alaska Fish Passage Program (USFW/AFPP) Guidelines
The AOP design for the unnamed creek outfall crossing is consistent with the 2021 U.S. Fish and Wildlife
(USFW) Service design guidelines. The 2021 document generally follows the U.S. Forest Service stream simulation approach with certain modifications. The basis for AOP design is the geomorphic analog method. The underlying philosophy of the geomorphic analog method is similar to the stream simulation approach. However, many of the design criteria are based on the 100-year flood event as opposed to a specifically selected design flood. The following USFW/AFPP requirements have been incorporated into the AOP design:
Flood and Debris Conveyance: Culvert capacity is designed to accommodate the 100-year recurrence flood without interfering with the functioning of the floodplain while providing adequate clearance above the flood stage for expected debris.
Memo to: Stacy Bluhm, WFLHD Project Manager
June 2023
Crossing Location: Crossing structure is placed within the pre-development natural channel alignment wherever possible.
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. All culverts will meet design requirements for a 6-foot minimum diameter.
Channel Vertical Clearance: Clearance from bed to ceiling must be at least 4-feet to allow for ease of construction, maintenance, and debris removal. Where possible, clearance will be 5-feet or greater.
Channel Slope: Reconstructed streambed within the culvert approximates the average slope of the stream reference reach. The slope should not deviate by more than 25% from the natural stream slope of the reference reach.
Embedment: Bottoms of round culverts should be buried below the streambed thalweg a minimum of
40% of the pipe diameter. Box or pipe arch culverts should be buried a minimum of 20% of the culvert’s rise.
Maximum Length of Road Crossing: Length should be less than 150-feet.
Fill Materials: Fill materials are generally comprised of sediment similar in size composition to natural bed materials that form the natural stream channel above and below the road crossing. Larger material is added to assist grade retention and provide resting areas for migrating fish. A dense, well-graded mixture is specified, with washing in of fines between constructed lifts, to encourage the stream to flow on the surface.
Fill/substrate material for culverts without an adequate sediment supply, such as those situated below a lake or wetland, should be designed to resist the predicted critical shear forces of the 100-year flood.
Water Depth and Velocity: Bankfull water depths and velocities in the culvert must closely resemble those existing reference reach as specified in the 2021 USFW Service guidance document.
Unnamed Creek AOP Culvert
The United States Fish and Wildlife Service (USFWS) has determined that an unnamed creek which crosses
Upper Skilak Lake Road requires an AOP structure (60.441910°, -150.317851°). Federal Lands Highway
Division conducted field reconnaissance of the crossing in 2020 and 2021. This reconnaissance data and fish passage assessment data from a FWS 2018 field survey were used to assess crossing and stream conditions.
The stream is a single thread channel that flows out of Lower Ohmer Lake and travels in southerly direction towards Skilak Lake. The crossing is located approximately 0.5 miles below the outlet of Lower Ohmer
Lake and approximately 1,500 feet upstream of Skilak Lake (Figure 1). The stream crosses Upper Skilak
Lake Road through one CMP with a 60-inch rise and 72-inch span. The valley slope between Lower Ohmer
Lake and Upper Skilak Lake Road is approximately 3.2%. As the stream approaches the road, the valley narrows, and the stream is further constricted by the roadway embankment. The channel slope increases to roughly 7% in the reach (300 ft) immediately upstream of the culverts. This portion of the stream flows through large moraine boulder and has a step-pool morphology. The bankfull channel width varies from about 4 feet to just under 7 feet (Photos 3 and 4). Bankfull depths range from 0.7 to 2.2 feet. Woody debris was observed in the channel which was supplied by the steeply wooded banks. Due to the narrow channel widths and large boulder obstructions, larger wood debris remains in place with only the smaller and some medium size debris being transported by the stream.
Downstream of the crossing, the channel continues to be confined by the roadway embankment and the slope steepens to roughly 8.5%. Patches of bedrock were exposed along the channel bottom and bank near the culvert outlet. The degradation potential will be limited by this bedrock. Step-pool is the dominant bedform in the upper reach of this section and bankfull widths/depths appear to be similar to those immediately upstream of the culvert (Photo 5).
Bed material upstream and downstream of the crossing includes gravel, large cobbles, and boulders. A single pebble count was carried out on the creek. The pebble count data was processed using FHWA
Hydraulic Toolbox, version 4.2, to compute the resulting gradation: D100 25.6-inches, D85 3.8-inches, D50 1.72-inches, D15 0.13-inches, and D5 0.08-inches (Figure 3).
The existing crossing is served by one CMP with a 60-inch rise and 72-inch span (Photos 1 and 2). The outlet of the culvert is perched and presents a barrier to upstream passage of fish, especially during periods of low flow. Although woody debris was noted in the channel, the culvert itself was clear of obstructions
(Photo 6). The existing culvert is skewed at an angle to the roadway to facilitate alignment of the upstream and downstream thalwegs of the channel.
Recommendations:
The existing culvert does not meet USFWS standards for fish-bearing stream crossings and inhibits aquatic organism passage. A larger pipe will be required to replace the existing culvert as well as provide space for bankfull width, a natural channel bottom, and stable banks.
• Install a 118-foot long corrugated, metal, round culvert with a 9-foot diameter.
• Install the new culvert approximately 40 feet south to avoid the bedrock on the east side of the road and align it with the existing stream channel.
• Excavate a channel matching the existing stream’s geometry along the west side of the road to direct the stream into the new culvert inlet.
• Place the culvert at an 8.68% slope to match channel slopes at the crossing by setting the inverts at elevation 293.55-feet upstream and at elevation 283.31-feet downstream (project datum).
• Embed the culvert a minimum of 3.6 feet and backfill the culvert interior with streambed material conserved during excavation of the culvert. If the conserved streambed material quantity is insufficient for backfilling the culvert, use material similar to the natural streambed material.
Streambed material will be augmented with Class D gradation cobbles specified in the attached
Special Contract Requirements (SCR) and Gradation Stability Calculations to provide a dynamically stable substrate.
• Allow clearance for debris passage and maintenance access by providing 5.4 feet of clearance from the crown of the culvert and the installed bed material.
• Construct a channel with a bankfull width of 6.7 feet and a bankfull depth of 1 foot including streambanks inside the culvert to provide resting opportunities for fish.
• Install sediment retention sills spaced 3.8 feet through the culvert to prevent loss of streambed material and only allow a maximum 4-inch drop from the top of the sill to the top of the pool formed by the downstream sill.
• Install rock weirs spaced 7.6 feet apart. The rock weirs inside the culvert should line up with every second retention sill so that footer rocks are braced against the sill.
• Install 15 round boulders, approximately 24-inches in diameter, for inducing channel migration and providing low velocity fish resting areas.
• Install concrete collars to mitigate the influence of frost heaving at pipe ends.
• Install Class 3 riprap (FHWA FP-14), minimum 3 feet thick, at the inlet and outlet for controlling erosion near the culvert.
• Install an additional 57-inch by 38-inch overflow arch pipe to reduce velocities in the main culvert during higher flows.
Construction
The Alaska Department of Fish and Wildlife instream work period is May 15 to July 15. 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 11-feet per second parallel flow. Use plastic-lined channels or pipes for temporally conveying stream flow through the construction area. Protect the outfalls from erosion. Ensure fish can pass smoothly through the diversion. Temporary stream diversions in place must provide an equivalent capacity to a 2.5-foot diameter pipe or demonstrate a minimum flow capacity equal to the 2-year discharge (65-cfs). Before installing the flow deflectors, remove fish from the work area to the level and methods meeting the 2009 ADF&G and FHWA Fish Habitat MOU requirements.
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 treatment area near the site.
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.
Stream Impacts
The proposed fish passage culvert is expected to dramatically improve stream flow conveyance, sediment transport, and woody debris transport to a level comparable to reaches upstream and downstream of the 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
Scour or aggradation of the streambed is 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 during the first few years to ensure that excessive debris accumulation, scour, or aggradation does not impair passage through the culvert. Increase the frequency of culvert inspections and debris removal for the first three years. Fish boulders and rock weirs 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 rock or boulders. Additional rock may need to be installed to correct erosion or channel degradation. 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 negatively impact flooding at the site.
Hydrology
The USGS StreamStats (version 4) web-based application was used for delineating the watershed and calculating drainage area (4.6 sq. miles) and mean annual precipitation (18-inches). Since delineations made by StreamStats can include inaccuracies for smaller watersheds and flat areas, the delineated watershed was verified by comparing it to both USGS TOPO maps and Digital Terrain Maps produced by the Alaska
Division of Geological and Geophysical Surveys. No significant deviations that would impact flow estimates were found.
Peak discharges were estimated with StreamStats using USGS regression equations from Magnitude and
Frequency at Gaged and Ungaged Sites on Streams in Alaska and Conterminous Basins in Canada (USGS
WRIR 2016-5024). The watershed is mostly comprised of forested lands as well as several lakes and ponds including Upper and Lower Ohmer Lakes (Figure 2). These lakes may influence the amount of runoff generated by the basin in two distinct manners. They have the potential to increase runoff due their large impervious surface area. However, lakes may also attenuate surface water flow withing the basin.
Hydraulic modeling of the channel and the existing culverts indicate that the flows derived from the USGS regression equations are likely reasonable estimates of the basin’s hydrology. A summary of peak discharges and their corresponding water depths at the culvert inlet are presented in Table 1.
Dominant flooding is from snow melt. Larger floods typically occur in April and May. Rain-on-snow flood events can occur in October through December. Lower flows typically occur from January to February and
July through September.
Culvert Hydraulics
Water surface profiles and culvert capacities were estimated using the FHWA Culvert Hydraulics Analysis
Program, HY-8, version 7.7 (results attached). Floods larger than the 2-year were analyzed assuming culvert slope of 8.71 percent and Manning’s Roughness coefficient of 0.032 for the channel bottom and 0.024 for the culvert sides and top.
The computed outlet tailwater depth of 0.9 for the 2-year discharge was compared with the bankfull channel design depth of 1.0 feet and found to be within the measured range of 0.7 to 2.2 feet in the natural channel.
Hydraulic results are included in the attachments with headwater depths and ratios shown in Table 2.
Attachments: Table 1 - Peak Discharge Estimates
Table 2 – Headwater Depths and Ratios
Figures 1, 2, and 3
Photographs
HY-8 Calculations
USGS StreamStats Report
Drawings
Special Contract Requirements and Gradation Stability Calculations
Tables
Table 1. Peak Discharges Estimates Peak Annual Floods Discharge (ft3/2)
2-Year 65 5-Year 117
10-Year 159 25-Year 219 50-Year 266
100-Year 317 200-Year 370 500-Year 445
Table 2. Peak Discharges and Water Depths Peak Annual
Floods Discharge (ft3/2) Headwater Depth (ft) HW/D
(D=5.4 ft) 2-Year 65 1.80 0.33
50-Year 266 4.36 0.81 100-Year 317 4.96 0.92
D = Distance between culvert crown and streambed
Image date: 4/17/2011
Project AOP Culvert Site Location
Project Area Location
USGS Topographic Maps on Google Earth
N
FIGURE 1
UNNAMED CREEK
AOP CULVERT
SITE LOCATION
Unnamed Creek AOP
2500 feet0
Map printed from Google Earth, Image date 4/17/2011.
N
DA = 4.59 sq. mi.
FIGURE 2
UNNAMED CREEK
AOP CULVERT
DRAINAGE AREA
0 2500 feet
FIGURE 3
UNNAMED CREEK
AOP CULVERT
STREAMBED GRADATION
Photos
PHOTO 1
7/2021
PHOTO 2
7/2021
PHOTO 3
7/2021
Unnamed Creek AOP
Upstream view of channel above the culvert. Bankfull width varies between 5 and seven feet.
Veiw of culvert outlet. Culvert is perched and exit obstructed by large woody debris.
Channel upstream of culvert.
Culvert Inlet.
View of 60" x 70" culvert inlet.
Culvert Outlet.
Photos
PHOTO 4
7/2021
PHOTO 5
9/2020
PHOTO 6
7/2021
View of channel below culvert, looking downstream. Large wood debris observed in channel.
Culvert interior.
Unnamed Creek AOP
Interior of culvert is free of debris.
Channel upstream of culvert.
Downstream view of channel above culvert looking towards the intlet.
Channel exhibits step-pool morphology.
Channel downstream of culvert.
HY-8 Culvert Analysis Report - Proposed AOP Crossing Discharge Data Discharge Selection Method: Specify Minimum, Design, and Maximum Flow
Minimum Flow: 65.00 cfs
Design Flow: 266.00 cfs
Maximum Flow: 317.00 cfs
Table 1 - Summary of Culvert Flows at Crossing: Unnamed Creek Headwater Elevation (ft)
Total Discharge (cfs)
Unnamed Creek AOP Discharge (cfs)
Flood Overflow Discharge (cfs)
Roadway Discharge (cfs)
Iterations
298.95 65.00 64.97 0.00 0.00 4
299.35 90.20 88.33 1.85 0.00 4
299.70 115.40 109.16 6.23 0.00 4
300.02 140.60 128.73 11.84 0.00 3
300.33 165.80 147.45 18.34 0.00 3
300.63 191.00 165.75 25.24 0.00 3
300.93 216.20 184.05 32.15 0.00 3
301.23 241.40 201.95 39.40 0.00 2
301.51 266.00 219.36 46.64 0.00 3
301.81 291.80 237.71 54.10 0.00 3
302.11 317.00 255.92 61.09 0.00 3
303.50 427.34 339.99 87.34 0.00 Overtopping
Rating Curve Plot for Crossing: Unnamed Creek
Culvert Data: Unnamed Creek AOP
Table 1 - Culvert Summary Table: Unnamed Creek AOP 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)
65.00 cfs 64.97 cfs 298.95 1.80 0.0* 1- S2n
0.72 1.18 0.72 0.92 10.13 11.37
90.20 cfs 88.33 cfs 299.35 2.20 0.0* 1- S2n
0.88 1.45 0.88 1.11 11.32 12.59
115.40 cfs 109.16 cfs 299.70 2.55 0.0* 1- S2n
1.00 1.67 1.00 1.27 12.22 13.55
140.60 cfs 128.73 cfs 300.02 2.87 0.0* 1- S2n
1.11 1.86 1.11 1.42 12.98 14.36
165.80 cfs 147.45 cfs 300.33 3.18 0.0* 1- S2n
1.21 2.03 1.21 1.57 13.64 14.01
191.00 cfs 165.75 cfs 300.63 3.48 0.0* 1- S2n
1.31 2.19 1.32 1.66 14.12 14.12
216.20 cfs 184.05 cfs 300.93 3.78 0.0* 1- S2n
1.40 2.35 1.40 1.74 14.77 14.33
241.40 cfs 201.95 cfs 301.23 4.08 0.0* 1- S2n
1.48 2.49 1.48 1.81 15.27 14.60
266.00 cfs 219.36 cfs 301.51 4.36 0.0* 1- S2n
1.56 2.63 1.56 1.88 15.73 14.89
291.80 cfs 237.71 cfs 301.81 4.66 0.0* 1- S2n
1.65 2.77 1.65 1.95 16.17 15.19
317.00 cfs 255.92 cfs 302.11 4.96 0.0* 1- S2n
1.73 2.90 1.73 2.01 16.60 15.50
* Full Flow Headwater elevation is below inlet invert.
Culvert Barrel Data Culvert Barrel Type Straight Culvert
Inlet Elevation (invert): 297.15 ft, Outlet Elevation (invert): 286.91 ft
Culvert Length: 118.44 ft, Culvert Slope: 0.0868
Culvert Performance Curve Plot: Unnamed Creek AOP
Water Surface Profile Plot for Culvert: Unnamed Creek AOP
Site Data - Unnamed Creek AOP Site Data Option: Culvert Invert Data
Inlet Station: 0.00 ft
Inlet Elevation: 293.55 ft
Outlet Station: 118.00 ft
Outlet Elevation: 283.31 ft
Number of Barrels: 1
Culvert Data Summary - Unnamed Creek AOP Barrel Shape: Circular
Barrel Diameter: 9.00 ft
Barrel Material: Corrugated Steel
Embedment: 43.20 in
Barrel Manning's n: 0.0240 (top and sides)
Manning's n: 0.0320 (bottom)
Culvert Type: Straight
Inlet Configuration: Beveled Edge (1:1)
Inlet Depression: None
Culvert Data: Flood Overflow
Table 2 - Culvert Summary Table: Flood Overflow 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)
65.00 cfs 0.00 cfs 298.95 0.00 0.000 0-NF 0.00 0.00 0.00 0.92 0.00 11.37
90.20 cfs 1.85 cfs 299.35 0.40 0.0* 1-
S2n
0.18 0.28 0.18 1.11 4.82 12.59
115.40 cfs 6.23 cfs 299.70 0.75 0.0* 1- S2n
0.31 0.52 0.31 1.27 7.10 13.55
140.60 cfs 11.84 cfs 300.02 1.07 0.0* 1- S2n
0.43 0.74 0.43 1.42 8.86 14.36
165.80 cfs 18.34 cfs 300.33 1.38 0.0* 1- S2n
0.53 0.94 0.53 1.57 10.29 14.01
191.00 cfs 25.24 cfs 300.63 1.68 0.0* 1- S2n
0.63 1.13 0.63 1.66 11.46 14.12
216.20 cfs 32.15 cfs 300.93 1.98 0.0* 1- S2n
0.71 1.29 0.73 1.74 11.96 14.33
241.40 cfs 39.40 cfs 301.23 2.28 0.0* 1- S2n
0.79 1.45 0.79 1.81 13.30 14.60
266.00 cfs 46.64 cfs 301.51 2.56 0.0* 1- S2n
0.87 1.60 0.89 1.88 13.60 14.89
291.80 cfs 54.10 cfs 301.81 2.86 0.0* 1- S2n
0.94 1.74 0.94 1.95 14.75 15.19
317.00 cfs 61.09 cfs 302.11 3.16 0.0* 1- S2n
1.01 1.87 1.01 2.01 15.34 15.50
Inlet Elevation (invert): 298.95 ft, Outlet Elevation (invert): 288.00 ft
Culvert Length: 112.53 ft, Culvert Slope: 0.0978
Culvert Performance Curve Plot: Flood Overflow
Water Surface Profile Plot for Culvert: Flood Overflow
Site Data - Flood Overflow
Inlet Station: 0.00 ft
Inlet Elevation: 298.95 ft
Outlet Station: 112.00 ft
Outlet Elevation: 288.00 ft
Number of Barrels: 1
Culvert Data Summary - Flood Overflow Barrel Shape: Pipe Arch
Barrel Span: 57.00 in
Barrel Rise: 38.00 in
Barrel Material: Steel or Aluminum
Embedment: 0.00 in
Barrel Manning's n: 0.0240
Culvert Type: Straight
Inlet Configuration: Projecting
Tailwater Data for Crossing: Unnamed Creek
Table 2 - Downstream Channel Rating Curve (Crossing: Unnamed Creek) Flow (cfs) Water
Surface Elev (ft)
Velocity (ft/s)
Depth (ft) Shear (psf) Froude Number
65.00 287.83 0.92 11.37 5.16 2.29
90.20 288.02 1.11 12.59 6.22 2.34
115.40 288.18 1.27 13.55 7.14 2.37
140.60 288.33 1.42 14.36 7.97 2.40
165.80 288.48 1.57 14.01 8.82 3.14
191.00 288.57 1.66 14.12 9.31 2.97
216.20 288.65 1.74 14.33 9.76 2.87
241.40 288.72 1.81 14.60 10.18 2.80
266.00 288.79 1.88 14.89 10.56 2.75
291.80 288.86 1.95 15.19 10.94 2.72
317.00 288.92 2.01 15.50 11.30 2.69
Tailwater Channel Data - Unnamed Creek Tailwater Channel Option: Irregular Channel
Channel Slope: Irregular Channel
User Defined Channel Cross-Section Coord No. Station (ft) Elevation (ft) Manning's n 1 0.00 292.91 0.0350 2 5.00 288.41 0.0350 3 10.00 288.41 0.0350 4 12.00 286.91 0.0320 5 17.00 286.91 0.0320 6 19.00 288.41 0.0350 7 24.00 288.41 0.0350 8 27.00 292.91 0.0000
Roadway Data for Crossing: Unnamed Creek Roadway Profile Shape: Constant Roadway Elevation
Crest Length: 100.00 ft
Crest Elevation: 303.50 ft
Roadway Surface: Gravel
Roadway Top Width: 24.00 ft
HY-8 Culvert Analysis Report - Existing Conditions
Crossing Discharge Data
Discharge Selection Method: Specify Minimum, Design, and Maximum Flow
Minimum Flow: 65.00 cfs
Design Flow: 266.00 cfs
Maximum Flow: 317.00 cfs
Table 1 - Summary of Culvert Flows at Crossing: Unnamed Creek Existing Conditions
Headwater Elevation (ft)
Total Discharge (cfs)
Unnamed Creek culvert Discharge (cfs)
Roadway Discharge (cfs)
Iterations
298.07 65.00 65.00 0.00 1
298.71 90.20 90.20 0.00 1
299.35 115.40 115.40 0.00 1
300.04 140.60 140.60 0.00 1
300.84 165.80 165.80 0.00 1
301.78 191.00 191.00 0.00 1
302.16 216.20 200.01 15.97 9
302.28 241.40 202.83 38.36 6
302.37 266.00 205.05 60.74 5
302.46 291.80 207.05 84.36 4
302.54 317.00 208.84 107.95 4
302.00 196.31 196.31 0.00 Overtopping
Rating Curve Plot for Crossing: Unnamed Creek Existing Conditions
Culvert Data: Unnamed Creek culvert
Table 1 - Culvert Summary Table: Unnamed Creek culvert
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)
65.00 cfs 65.00 cfs 298.07 2.67 0.0* 1-S2n 1.03 1.71 1.03 0.88 12.61 10.74
90.20 cfs 90.20 cfs 298.71 3.32 0.0* 1-S2n 1.23 2.05 1.23 1.04 14.03 11.97
115.40 cfs 115.40 cfs 299.35 3.96 0.0* 1-S2n 1.42 2.36 1.46 1.18 14.69 12.95
140.60 cfs 140.60 cfs 300.04 4.65 0.0* 5-S2n 1.59 2.65 1.64 1.30 15.55 13.75
165.80 cfs 165.80 cfs 300.84 5.45 0.675 5-S2n 1.76 2.91 1.83 1.41 16.21 14.43
191.00 cfs 191.00 cfs 301.78 6.39 1.720 5-S2n 1.92 3.14 2.01 1.51 16.81 15.01
216.20 cfs 200.01 cfs 302.16 6.76 2.116 5-S2n 1.98 3.22 2.07 1.61 17.03 15.53
241.40 cfs 202.83 cfs 302.28 6.88 2.242 5-S2n 2.00 3.25 2.09 1.70 17.08 16.00
266.00 cfs 205.05 cfs 302.37 6.98 2.877 5-S2n 2.01 3.26 2.11 1.78 17.12 16.42
291.80 cfs 207.05 cfs 302.46 7.07 2.959 5-S2n 2.02 3.28 2.12 1.86 17.15 16.82
317.00 cfs 208.84 cfs 302.54 7.15 3.034 5-S2n 2.03 3.30 2.14 1.94 17.19 17.18
Inlet Elevation (invert): 295.39 ft, Outlet Elevation (invert): 290.69 ft
Culvert Length: 76.77 ft, Culvert Slope: 0.0614
Culvert Performance Curve Plot: Unnamed Creek culvert
Water Surface Profile Plot for Culvert: Unnamed Creek culvert
Site Data - Unnamed Creek culvert
Inlet Station: 0.00 ft
Inlet Elevation: 295.39 ft
Outlet Station: 76.62 ft
Outlet Elevation: 290.69 ft
Number of Barrels: 1
Culvert Data Summary - Unnamed Creek culvert
Barrel Shape: Pipe Arch
Barrel Span: 77.00 in
Barrel Rise: 52.00 in
Barrel Material: Steel or Aluminum
Embedment: 0.00 in
Barrel Manning's n: 0.0240
Culvert Type: Straight
Inlet Configuration: Projecting (Ke=0.9)
Tailwater Data for Crossing: Unnamed Creek Existing Conditions
Table 2 - Downstream Channel Rating Curve (Crossing: Unnamed Creek Existing Conditions)
Flow (cfs) Water Surface Elev (ft)
Velocity (ft/s) Depth (ft) Shear (psf) Froude Number
65.00 291.56 0.88 10.74 4.93 2.28
90.20 291.73 1.04 11.97 5.83 2.39
115.40 291.86 1.18 12.95 6.60 2.47
140.60 291.99 1.30 13.75 7.29 2.52
165.80 292.10 1.41 14.43 7.91 2.57
191.00 292.20 1.51 15.01 8.49 2.60
216.20 292.29 1.61 15.53 9.02 2.63
241.40 292.38 1.70 16.00 9.53 2.65
266.00 292.47 1.78 16.42 9.99 2.67
291.80 292.55 1.86 16.82 10.45 2.68
317.00 292.62 1.94 17.18 10.88 2.70
Tailwater Channel Data - Unnamed Creek Existing Conditions
Tailwater Channel Option: Irregular Channel
Channel Slope: Irregular Channel
User Defined Channel Cross-Section
Coord No. Station (ft) Elevation (ft) Manning's n
1 0.00 295.91 0.0350
2 5.00 293.41 0.0350
3 10.00 291.61 0.0350
4 12.00 290.69 0.0320
5 17.00 290.69 0.0320
6 19.00 291.61 0.0350
7 24.00 293.41 0.0350
8 27.00 295.91 0.0000
Roadway Data for Crossing: Unnamed Creek Existing Conditions
Roadway Profile Shape: Constant Roadway Elevation
Crest Length: 100.00 ft
Crest Elevation: 302.00 ft
Roadway Surface: Gravel
Roadway Top Width: 24.00 ft
SCALE IN FEET
10 0 10 20 30 40
OUTLETINLETPIPEHYDRAULIC INFORMATION
0 20 40 60 8020406080
LENGTH: 118 ft
PIPE SLOPE: 0.0868 ft/ft
HEADWALL: Riprap
FLOWLINE SLOPE: 0.0868 ft/ft
100 120100120140
Q : 65 CFS
Q : 266 CFS
BANKFULL CHANNEL WIDTH: 6.7 ft
TYPE: Metal round pipe SPAN: 9.0 ft RISE: 9.0 ft
LOWER BEVEL HEIGHT: 2.25 LOWER BEVEL HEIGHT: 2.25
BEVEL: 1.5h : 1v
HEADWALL: Riprap
BEVEL: 1.5h : 1v
Q : 317 CFS
INV N/E/EL: 2353574.42/1582985.46/293.55' /1583008.23/283.31'INV N/E/EL: 2353459.09
WALL THICKNESS: NA
:1
Existing ground
Slope 8.68%
Flow
Remove Existing 60" x 72" CMP
HW : 302.11 ft
Unnamed Creek
N
LC
OHW : 298.95 ft
Line to be constructed
BURIAL DEPTH: 3.6 ft BURIAL DEPTH: 3.6 ft
1:1
New culvert centerline metal round pipe culvert
9.0 foot diameter
304+77.67
305+27.16, 39.68 LT
304+34.08, 31.58 RT
PLAN AND PROFILE
UNNAMED CREEK CULVERT
[1]method B, class 3
Placed riprap
[1]method B, class 3
Placed riprap
[1]method B, class 3
Placed riprap
[1]method B, class 3
Placed riprap detail Sheet G.13
Backfill with streambed material per
FOOTNOTE:
See Sheet G.11 for riprap details.[1]
G.4
STATE PROJECT
NUMBER
SHEET
AK FWS KNA 1192(1)
V
B e v a n
J N e ig h o r n
/2
/2
C h e c k e d b y
D e s ig n e d b y
In t_ ft
D c p w w o r k \d
\a k r k e n a i1 h .d g n
Road centerline
Channel elev. 297.15
Channel elev. 286.91
Channel flowline
Road grade
:1
A
M
J u ly
Flow
3.8' spacing per detail sheet G.14.
Install sediment retention sills at
(48" equivalent diameter)
57" span, 38" Rise
Metal pipe arch:
Install overflow culvert
Cut and fill limits (typ.)
E 1583022.37
N 2353643.17
Begin channel grading
E 1583012.38
N 2353436.48
End channel grading
End channel grading
Concrete collar per detail sheet G.15
Install rock weirs at 7.6'' spacing
Begin channel grading
Concrete collar
Concrete collarE 1583004.43
N 2353606.49
1:1 9"
TYPICAL SECTION
CHANNEL GRADING
and seed
Place topsoil, 4" depth
143°
4.5'
3.8'(typ.)
.5
7.6' (typ.)
'R
'R
6.7' Bankfull width
12"
NOTE:
FOOTNOTE:
DETAILS
RIPRAP HEADWALL
Sl op e
PIPE BEVEL DETAIL
Sl op e
SKEW ANGLE DIAGRAM
c e n te r li n e
R o a d w a y
Cu lv er t ce nt er lin e
BOP
EOP
(DIAMETER OR SPAN GREATER OR EQUAL TO 48-INCHES)
(DIAMETER OR SPAN LESS THAN 48-INCHES)
.2
D o r R
.2
D o r R o r R is e
R
D ia m e te r
D o r R is e
R
D ia m e te r
D
W
Sl op e
FRONT VIEW SIDE VIEW
[2
24" shown in the plans
Streambed material where shown in the plans
Streambed material where
V a ri a b le R is e
W2
Variable W2 o r R is e
R
D ia m e te r
V a r ia b le
Placed riprap, class 3
Placed riprap, class 3
[3
" m in geotextile, class 1, type C
Separation and stabilization
Manufacturer's standards
0.25 D or R or per the
Optional
Skew
B e v n
N e ig h o r
/2
/2
C h e c k e d b y
D e s ig n e d b y
G.11
STATE PROJECT
NUMBER
SHEET
In t_ ft m y f il e s \p w p r o d u c ti o n
\d
\m t-a e z .d g n
AK FWS KNA 1192(1)
:5
A u g u s t beneath and at all sides of placed riprap.
Place earthwork geotextile between riprap and existing ground, Earthwork geotextile, type II-C is subsidiary to 251.
Contractor to field verify all invert elevations, prior to installation.
3.
2.
1.
shown on site specific details, whichever is greater.
Construct riprap end treatment to a thickness of 36-inches or as[3]
Riprap end treatment slope to match roadway embankment slope.[2]
Bevel to match roadway embankment.[1]
RIPRAP END TREATMENT
[1]
[1]
B e v
N e ig h o
/2
/2
C h e c k e d b y
D e s ig n e d b y
G.12
STATE PROJECT
NUMBER
SHEET
In t_ ft p w w o r k \d
\a k r k e n a i1 h .d g n
AK FWS KNA 1192(1)
:4 a y
SECTION VIEW
ANCHOR BOLT DETAIL
1.5
3'-0"
TYPICAL SECTION
THRU COLLAR
CONCRETE COLLAR
ISOMETRIC VIEW
3'-0"
3'
Sp an
3'
LC
Culvert crown
2' min. lap splice
#4 Reinf (6 total)
Culvert invert galvanized " Dia.4 bolt design - 4" hook
Acceptable anchorStructural plate pipe
18" o.c. See detail " Anchor bolt @4
#4
#4 stirrups m in
2' min. lap splice
#4 Reinf (6 total)
6" min.
To bedrock or 3' max.
To bedrock or 3' max.
COLLAR DETAILS
REINFORCED CONCRETE
LARGE CULVERT
SECTION A-A
PLAN
NOTE:
FOOTNOTE:
3.
2.
1.
Pipe arch culvert
W
Streambed sediment
Streambed cobble
Pipe arch culvert wall
Box culvert wall
Stagger in-channel fish passage boulders within the culvert span.
streambed cobble, and bank stone gradations.
See special contract requirements for streambed sediment, Mix streambed cobbles evenly throughout streambed sediment.
Channel flowline
Streambed sedimentRound pipe culvert wall Streambed top
Round culvert
Culvert wall
LC
Flow
BB
A where specified on plan per detail Sheet G.14
Sediment retention sill on plan where specified detail Sheet G.15
Rock weir per culvert boulder within
Fish passage where specified on plan per detail Sheet G.14
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
[2]Bank stone
[2]Bank stone
TREATMENT
STREAM CULVERT
SIMULATED
A Flow
SECTION B-B
(typ.)
36" min.
Streambed cobble
Culvert outlet where specified on plan per detail Sheet G.14
Sediment retention sill
[3]within culvert
Fish passage boulder
Streambed sediment plan sheet or Length on
LC
specified on plan
Sheet G.15 where
Rock weir per detail outlet
Culvert
LOCATION
(FT)
X
(CUYD)
COBBLE
STREAMBED
(CUYD)
SEDIMENT
STREAMBED
(CUYD)
STONE
BANK
GRADATION
COBBLE
STREAMBED
(FT)
W
MITIGATION
FISH PASSAGE BOULDER
(IN)
DIA. NO.
[4]STREAMBED MATERIAL
TOTAL
B e v
N e ig h o
/2
/2
C h e c k e d b y
D e s ig n e d b y
G.13
STATE PROJECT
NUMBER
SHEET
In t_ ft m y f il e s \p w p r o d u c ti o n
\d
\m t-a e w
.d g n
AK FWS KNA 1192(1)
:4
A u g u s t
JEAN CREEK NA 10
LOWER OHMER CREEK NA 7
UNNAMED CREEK 3.8 6.7
D
D
D
(IN)
BD
BD/3
3% (typ.)
Slope
B D
W
X (typ.)
X (typ.)
4' match rock weir spacing
Stagger fish boulders each side and d e p th
B u r ia l
B u r ia l d e p th
DETAIL
PLATE AND CONNECTOR
NOTE:
LC
H B
NO SCALE
24" typ.
FlowLC
H B
CROSS-SECTION
ROUND PIPE
SEDIMENT RETENTION SILLS
24" typ.
CROSS-SECTION
STRUCTURAL-PLATE PIPE ARCH
SEDIMENT RETENTION SILLS
X
B
H
CROSS-SECTION
PRECAST BOX CULVERT
SEDIMENT RETENTION SILLS
LC
DETAIL
CONCRETE SILL
X
Flow
DETAILS
SEDIMENT RETENTION SILL
CULVERT
H
0.25" retention sill
Top of sediment retention sill
Top of sediment
(0.25" A36 steel plate)
Gusset steel plate)
(0.25" A36
Gusset steel plate)
(0.25" A36
Gusset 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.)
Round pipe c l.
2" cl.
D
V a r ie s
D pipe arch culvert
Structural-plate wall Culvert
LOCATION (IN)
B
(IN)
H
(NO.)
Min.
SRS
(FT)
Max.
X
MITIGATION
SEDIMENT RETENTION SILLS (SRS)
locating SRS in corrugation valleys or away from plate seems.
X dimension may be varied +/- 6-inches as needed for
Apply two coats zinc paint to all welds.
Hot dip galvanized baffles and gussets.
3.
2.
1.
(A36 steel plate)
Sediment retention sill (SRS)
B e v
N e ig h o
/2
/2
C h e c k e d b y
D e s ig n e d b y
G.14
STATE PROJECT
NUMBER
SHEET
In t_ ft m y f il e s \p w p r o d u c ti o n \d
\m t-a e x .d g n
AK FWS KNA 1192(1)
:5
A u g u s t
UNNAMED CREEK 30 7.9 20 3.8
Flow
F lo wA
A
(in)
DIAMETER
FOOTER ROCK
TOP ROCK AND
(no.)
QUANTITY
ROCK WEIR
MITIGATION
ROCK WEIR
(ft)
B
(ft)
[5] Z
(ft)
W
LOCATION
ELEVATION
PLAN
SECTION A-A
DETAIL
ROCK WEIR
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
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
B e v
N e ig h o
/2
/2
C h e c k e d b y
D e s ig n e d b y
G.15
STATE PROJECT
NUMBER
SHEET
In t_ ft m y f il e s \p w p r o d u c ti o n \d
\m t-a e y .d g n
AK FWS KNA 1192(1)
:5
A u g u s t
JEAN CREEK 10.0 1.5 5.5 3
LOWER OHMER CREEK 7.0 1.0 4.5 4
UNNAMED CREEK 6.6 1.2 3.3 19
Z
D o w n s tr e a m f r o m c o n tr o l)
BWB
B W3
W 3
W3
B
W3
VAP
Existing ground
Roadway centerline
2000 50 100 15050100150200250300350
Unnamed Creek
Section 703. — AGGREGATE
703.18 Furnished Streambed Material. (Added Subsection).
Streambed material consists of streambed sediment and streambed cobbles (class A, B, C, D, or E as specified on the plans) with volumes of each specified on the plans. Provide a uniform mixture.
Furnish material consisting of hard, durable, free from seams, cracks, and other defects conforming to the following:
(a) Durability index, AASHTO T 210
(1) Course aggregate 35 min.
(2) Fine aggregate 35 min.
(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. 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)
3 ½ inch 100
3 inch 80 – 90
1 ½ inch 55 – 65
¾ inch 40 – 50
No. 4(1) 15 – 25
No. 10 15 min.
(1) No more than 0.2 percent woody debris retained.
(e) Gradation, Streambed Cobbles. Furnish material meeting the requirements of Table 703-14. 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 18” 100 12" 60-70 10" 100 8" 100 75-80 30-40 6" 100 50-60 10-20 5" 65-75 4" 65-75 30-40 3" 35-45 25-35 0-10 2" 35-45
1 ½" ¾" 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:
𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿ℎ + 𝑊𝑊𝑊𝑊𝑊𝑊𝐿𝐿ℎ + 𝑇𝑇ℎ𝑊𝑊𝑖𝑖𝑖𝑖𝐿𝐿𝐿𝐿𝑖𝑖𝑖𝑖
= 𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝑊𝑊𝐴𝐴𝐴𝐴𝐿𝐿𝐿𝐿 𝑆𝑆𝑊𝑊𝑆𝑆𝐿𝐿
Project:
Location/Stream:
New Stream Channel Design (Culvert, Rock Ramp)
FINE 50%
Using Corps of Engineers Equations - FHWA Circular on Development in the River System - Page 6.25. COARSE 50% FHWA NHI 01-004; River Engineering for Highway Encroachments, 2001 http://www.fhwa.dot.gov/engineering/hydraulics/library_arc.cfm?pub_number=8&id=20
YELLOW ARE INPUTS
Safety Factor 1.2 Stability Coefficient for Incipient Failure 0.36 (0.36 round rock, 0.3 angular rock) Vertical Velocity Distribution Coeff 1.00 (1.0 for straight channels) Blanket Thickness Coeff 1 (1xD100 or 1.5 or D50 max, whichever is greater) Local depth of flow 0.72 ft for 2 year event Unit Weight of water 62.4 lb/ft^3 assumed Unit weight of rock 165 lb/ft^3 assumed Local depth-average velocity 10.13 ft/s from 100-year event avg. velocity in pipe Side Slope correction factor 1 Gravitational Acceleration 32.2 ft/s^2 D85/D15 1.7 (1.7-5.2) D50/D30 1 Note: This method is based on the minimum D30 size Riprap Design Method - Selecting Proper Gradation, Page 131.
Design Hydrology and Sedimentology for Small Catchments, Haan, Barfield and Hayes, 1981.
D15 0.6 ft 7.0 inches D30 1.1 ft 13.0 inches D50 1.3 ft 16.0 inches D85 2.2 ft 27.0 inches
D100 2.6 ft 31.0 inches
Using D50 size, used FHWA circular for Rip Rap design to spec out D100, D85 and D15.
D100 = 2.0D50
Fuller-Thompson Estimating for Maximum Density: D100 (inches) 31.0 Method Adapted from US Forest Service Stream Simulation Guidelines D30 8.0 Stability (D30):
D30 Req'd 13.0
YELLOW ARE INPUTS COARSE FINES
Custom Fine Aggreg. Combined %F-T EQN Check Coarse Material Design -D30 Required per FHWA Method RELATIVE % = 0.50 0.50 1.0000 Riprap D30 Riprap Req 13.0
Size (inches) Sieve Size % Passing % Passing % Passing % Passing % Passing D30 Size = 8.0 54 54 in 1.00 1.00 100% 132% 100% No Not Good 48 48 in 1.00 1.00 100% 124% 100% No 44 44 in 1.00 1.00 100% 119% 100% No 42 42 in 1.00 1.00 100% 116% 100% No 36 36 in 1.00 1.00 100% 108% 100% No 30 30 in 1.00 1.00 100% 98% 100% No 24 24 in 1.00 1.00 100% 88% 100% No 18 18 in 1.00 1.00 100% 76% 100% No 13 13 in 0.60 1.00 80% 65% 60% No 8 8 in 0.30 1.00 65% 51% 30% 8.00 6 6 in 0.10 1.00 55% 44% 10% 6.00 3 3 in 0.00 0.85 43% 31% 0% 3.00
1.5 1.5 in 0.00 0.60 30% 22% 0% 1.50
0.75 0.75 in 0.00 0.45 23% 16% 0% 0.75
0.187 #4 0.00 0.20 10% 8% 0% 0.19
0.0787 #10 Sand 0.00 0.15 8% 5% 0% 0.08
Gradation values should be within +/-5% of this gradation (Rice) AND we need to have at least 5% sand size (#10) or smaller (Forest Service) in the combined gradation
DATA for Graph & Fuller-Thomson Eqn Size (in) Combined % pa F-T equation n (F-T)=
54.000 100% 132% D100 (in) =
48.000 100% 124%
44.000 100% 119%
42.000 100% 116%
36.000 100% 108%
30.000 100% 98%
24.000 100% 88%
18.000 100% 76%
13.000 80% 65%
8.000 65% 51%
6.000 55% 44%
3.000 43% 31%
1.500 30% 22%
0.750 23% 16%
0.187 10% 8%
0.079 8% 5%
Not Good
MATERIAL PROPORTIONS
AK FWS Kenai 1102(1) - Skilak Lake Road
Unnamed Creek
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.010 0.100 1.000 10.000 100.000
P as si ng
Particle Size
Design
Fuller-Thomson http://www.fhwa.dot.gov/engineering/hydraulics/library_arc.cfm?pub_number=8&id=20
YELLOW ARE INPUTS
Desired tolerance (+/-): 5%
SIEVE % PASSING
18 in 1.00 13 in 1.00 8 in 1.00 6 in 1.00 3 in 0.8 to 0.9
1.5 in 0.55 to 0.65
0.75 in 0.4 to 0.5
#4 0.15 to 0.25 #10 Sand 0.15 min
Desired tolerance (+/-): 5%
SIZE % PASSING
54 in 1.00 48 in 1.00 44 in 1.00 42 in 1.00 36 in 1.00 30 in 1.00 24 in 1.00 18 in 1.00 13 in 0.55 to 0.65 8 in 0.3 to 0.4 6 in 0.1 to 0.2
3 in 0 to 0.1
TABLE 1
FINE MATERIAL
TABLE 2
COARSE MATERIAL
| AK Unnamed Creek AOP Report |
| 1-AK Unnamed AOP Report Final |
| 2-Unnamed Tributary Tables |
| 3-UnnamedCreek AOPreport_figures1-3 |
| Fig 1 |
| Fig 2 |
| Fig 3 |
| 4-AOP Report Photos Unnamed Creek |
| HY8 Unnamed Creek.pdf |
| Crossing Discharge Data |
| Table 1 - Summary of Culvert Flows at Crossing: Unnamed Creek |
| Rating Curve Plot for Crossing: Unnamed Creek |
| Culvert Data: Unnamed Creek AOP |
| Table 1 - Culvert Summary Table: Unnamed Creek AOP |
| Culvert Barrel Data |
| Culvert Performance Curve Plot: Unnamed Creek AOP |
| Water Surface Profile Plot for Culvert: Unnamed Creek AOP |
| Site Data - Unnamed Creek AOP |
| Culvert Data Summary - Unnamed Creek AOP |
| Culvert Data: Flood Overflow |
| Table 2 - Culvert Summary Table: Flood Overflow |
| Culvert Barrel Data |
| Culvert Performance Curve Plot: Flood Overflow |
| Water Surface Profile Plot for Culvert: Flood Overflow |
| Site Data - Flood Overflow |
| Culvert Data Summary - Flood Overflow |
| Tailwater Data for Crossing: Unnamed Creek |
| Table 2 - Downstream Channel Rating Curve (Crossing: Unnamed Creek) |
| Tailwater Channel Data - Unnamed Creek |
| User Defined Channel Cross-Section |
Roadway Data for Crossing: Unnamed Creek
| HY8Report_Unnamed Creek-Existing |
| AK Unnamed Creek AOP Report |
| 7-UnnamedCreek___streamstats.usgs |
| 8- G sheet Nd more |
| Unnamed G-Sheets Revised 6-14-23 |
| G14 |
| Unnamed G-Sheets Revised 6-14-23 |
| Unnamed Long Profiles |
| SCR 703 Furnish Streambed Material - Skilak |
| Section 703. — Aggregate |
| 703.18 Furnished Streambed Material. |
Streambed Material Sizing Analyzer_Unnamed Creek
| Streambed Material Sizing Analyzer_Unnamed Creek.pdf |
| Custom Coarse Material Example |
File details come from the government source that posted it. Updated .