Hydrology and Hydraulics Report.pdf

EFLHD TO 19 KS KIRW

Xavier Road

Hydrology and Hydraulics

Recommendations Report

Federal Highway Administration

Eastern Federal Lands Highway Division

Prepared by

HDR Engineering, Inc.

January 25, 2020

EFLHD TO 19 KS KIRW 1 Eastern Federal Lands Highway Division Xavier Road Hydrology and Hydraulics

1. Introduction

Project Description HDR is preparing a Project Delivery Plan for the Federal Highway Administration, Eastern Federal

Lands Highway Division (EFLHD) for proposed improvements to roads within the Kirwin National

Wildlife Refuge, Kirwin, Kansas. This Scope of Work (SOW) is to perform environmental, highway engineering, hydraulic engineering, geotechnical engineering, surveying, mapping, and project management services. The general scope of roadway improvements is programmed as rehabilitation of existing roadway and parking areas on 1.01 miles of Xavier Road, 6.85 miles of

Auto Tour Road and Parking Areas 900, 901, 909, 914, 940 and 945. These improvements will be designed and implemented in accordance with Fish and Wildlife Service, EFLHD, and

AASHTO Highway Design Standards, in cooperation with the Fish and Wildlife Service, Kirwin

National Wildlife Refuge. The road is maintained by the Fish and Wildlife service.

Hydraulic engineering tasks include:

Recommend improvements to existing culverts on the Auto Tour Road

Recommend repairs to damaged culverts

Recommend the replacement of culverts that cannot be repaired

Design culvert repairs and replacements

This report serves as the basis for hydrologic and hydraulic analysis of existing culverts and provides preliminary recommendations for culvert repairs/replacements.

Project Location The project is located entirely on Federal Lands within the Kirwin National Wildlife Refuge in

Phillips County, Kansas as shown on Figure 1. Phillips County does not participate in the National

Flood Insurance Program and is unmapped. The City of Kirwin is entered into FEMA’s Emergency

Program but also does not participate in the National Flood Insurance Program and is unmapped.

Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community

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FIGURE 1. SITE MAP

XAVIER ROAD

PRELIMINARY HYDROLOGY AND HYDRAULICS RECOMMENDATIONS REPORT

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Bow Creek

North Fork Solomon River

Kirwin Reservoir

E Xavier Rd

S K irw in L ake

Rd

¬«9

PhillipsPhillips SmithSmith

OsborneOsborneRooksRooks

£¤36

£¤183

£¤281

£¤24

¬«8

¬«9 Project Location

Station 88+32

Station 122+25

Station 136+70

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Design Criteria The Kansas Department of Transportation (KDOT), Bureau of Road Design “Design Manual” supplemented with Chapter 7 of the FLH "Project Development and Design Manual" (PDDM) are used as the basis to evaluate existing culverts, size culvert replacements, and design culvert outlet and embankment protection.

South Kirwin Lake Road and East Xavier Road are both classified by KDOT as local roads.

According to KDOT’s Design Manual (KDOT, 2016), the appropriate design recurrence interval for local roads is the 10-year storm. Additionally, based on conversations with EFLHD, the culverts undergoing replacement can be accurately characterized as vented low-water crossings, which also require a 10-year capacity design storm as specified in the FLH PDDM (FLH, 2012).

Therefore the 10-year recurrence interval (10% AEP) was used as the design storm for evaluating and sizing culverts and the 25-year recurrence interval (4% AEP) was used as a check for depth of overtopping and scour at the roadway embankments.

Culverts were also designed such that the headwater to depth ratio is less than 1.2 for the design discharge (FLH, 2012). In addition, headwater elevations for the 10-year design storm are limited to maintain at least 2 feet of freeboard to the bottom of the roadway pavement structure at the local roadway low point.

2. Hydrology KDOT’s Design Manual is used as the basis for hydrologic design and determination of peak flow discharges.

Peak flow determination includes:

Bow Creek

North Fork of the Solomon River

Local cross culvert drainage basins

Flows through Bow creek are of interest to evaluate the effects of downstream scour from the main channel and to evaluate tailwater conditions for the road crossings being analyzed. Similarly, the flows tributary to Kirwin Reservoir from the North Fork of the Solomon River are of interest to determine if the reservoir backs up during peak events further raising the tailwater.

Prediction of Channel Design Discharges The United States Geological Survey (USGS) Gage 06871500, Bow Creek near Stockton, Kansas, and USGS Gage 06871000, North Fork Solomon River at Glade, Kansas, were used to estimate peak discharges into Kirwin Reservoir. The Bow creek gage has a period of record of 67 years, with data from 1951 to 2017 and the North Fork Solomon River gage has a period of record of 64 years, with data from 1953 to 2017. Peak flow data in cubic feet per second (cfs) for both gages are presented in Figure 2.The gages are located 8 to 12 miles upstream of Kirwin Reservoir at the stream crossings with U.S. Highway 183, as presented in Figure 3.

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Figure 2. Annual peak flows from USGS Gages 06871500 and 06871000

Sources: Esri, USGS, NOAA, Sources: Esri, Garmin, USGS, NPS

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FIGURE 2. USGS STREAM GAGES

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E Xavier Rd

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USGS Gage 06871000 North Fork Solomon River at Glade, Kansas

USGS Gage 06871500 Bow Creek near Stockton, Kansas

E 7

R d

E 1

0 R d

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To determine flood flow frequencies for Bow Creek and the North Fork of the Solomon River the drainage-area ratio method outlined in the United States Geological Survey (USGS) Scientific

Investigations Report 2017–5063 was applied to the results of a Bulletin 17B analysis of annual peak flows recorded at USGS stream gage on Bow Creek and gage 06871000 on the North Fork of the Solomon River at Glade.

The Hydraulic Engineering Center’s Statistical Software Package (HEC-SSP) was used to analyze the gage data for the period of record. HEC-SSP can utilize the Bulletin 17b method or the EMA (Bulletin 17c) method. The regionalized-skew of -0.478 and the Root Mean Square Error of 0.210 presented in SIR 2017-5063 were used for the analysis. The estimated peak discharges at USGS Gages 06871500 and 06871000 using the period of record are presented in Table 1.

Table 1: Estimated peak discharges at USGS Gages 06871500 and 06871000

USGS Gage 10% Annual Exceedance

Probability (AEP)

4% AEP

06871500, Bow Creek near Stockton, KS 5,104 cfs 9,183 cfs

06871000, North Fork Solomon River at Glade, KS 6,276 cfs 10,444 cfs

In order to estimate peak discharges at Kirwin Reservoir, a drainage-area ratio method for estimating peak discharges for sites near gaging stations on the same stream was used (Painter, 2017). The equation for determining peak flow at Kirwin Reservoir, or ungaged site, (Qt(u)) is:

QT(u)g = ( Au

Ag b

QT(g)w

The equation variables and values are described in Table 2.

Table 2. Variables and values for determining peak flow at Kirwin Reservoir

Variable Description Bow Creek NF Solomon River

Ag Drainage area of gaged site (square miles)

352.01 849.01

Au Drainage area of ungaged site (square miles)

390.71 990.61

AEP 10% 4% 10% 4%

b Exponent for drainage area from the appropriate P-percent AEP regional equation presented in SIR 2017-5063

0.374 0.375 0.374 0.375

QT(g) Peak discharge at gaged site for gaged site for T-year recurrence interval (cfs)

5,1042 9,1832 6,2762 10,4442

1Drainage areas estimated from the USGS 12 digit Hydrologic Unit Code watersheds 2See Table 1

The method is reliable when the drainage-area ratio is between 0.5 and 1.5 (Painter, 2017). The ratio of Au/Ag is 1.11 and 1.17 for Bow Creek and North Fork Solomon River, making the method appropriate for this application. The peak flows at Kirwin Reservoir are presented in Table 3.

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Table 3: Estimated peak discharges at USGS Gages 06871500 and 06871000

Location 10% AEP 4% AEP

Bow Creek at E 700 Rd upstream of Kirwin Reservoir 5,307 cfs 9,550 cfs

North Fork Solomon River at Kirwin Reservoir 6,649 cfs 11,066 cfs

Prediction of Culvert Crossing Design Discharges Design discharges were developed for the three locations undergoing culvert replacement, designated as drainage basins A, B, and C as shown in Figure 4. These were determined using the flood hydrograph simulation method outlined in Section 11 of the KDOT Design Manual.

Drainage basins tributary to the culverts of interest were delineated using the ArcHydro tools with the one-meter resolution digital elevation model (DEM) published in 2017. Drainage basins were further refined to account for roadway crossings using 1-foot contours generated from the DEM.

Figure 4 shows the drainage basins associated with the culverts that were analyzed as well as the longest flow paths for each basin.

The Natural Resources Conservation Service (NRCS) curve-number method was used to generate design storm runoff hydrographs. Composite runoff curve numbers (RCN) for each drainage basin were calculated following the methods presented in section 11.5 of KDOT’s

Design Manual. RCNs were assigned based on the hydrologic soil group and land cover combination. Composite RCNs were computed for each basin as the area weighted average.

Hydrologic soil groups were taken from NRCS soil surveys KS147 (Phillips County) and KS163

(Rooks County), provided in Appendix A. Land cover types were determine by matching the 2011

National Land Cover Data Set (NLCD) to the cover descriptions presented in Table 11.5.4-1 of

KDOT’s Design Manual. Table 4 presents an excerpt from Table 11.5.4-1 matching cover descriptions with NLCD land covers found within the drainage basins as well as the assigned

RCN for each hydrologic soil group. The RCNs presented are associated with an antecedent moisture condition of 2.

C B

A

Sources: Esri, HERE, Garmin, Intermap, increment P Corp., GEBCO, USGS, FAO, NPS, NRCAN, GeoBase, IGN, Kadaster NL, Ordnance Survey, Esri Japan, METI, Esri China (Hong Kong), swisstopo, © OpenStreetMap contributors, and the GIS User Community

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FIGURE 3. DRAINAGE BASINS

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LEGEND

Longest Flow path with 10% and 85% length markers Drainage Basins

Analyzed Road Crossings !. Culvert Replacement

#I Embankment Protection

$1 Riprap Inlet/Outlet Protection

Bow Creek

North Fork Solomon River

S Kirwin Lake Rd

Station 88+32 Station 122+25 Station 136+70

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Table 4. Runoff Curve Numbers

NLCD Code & Land Cover

Table 11.5.4-1 Cover Description

RCN corresponding to hydrologic soil group

A B C D

11. Open Water Impervious areas 98 98 98 98

21. Developed, Open Space

Open space (lawns, parks, golf courses, etc.)

Good Condition (grass cover >75%)

39 61 74 80

22. Developed, Low Intensity

Residential districts by average lot size 1 acre (20% imp.)

51 68 79 84

23. Developed, Medium Intensity

Residential districts by average lot size 1/4 acre (38% imp.)

61 75 83 87

31. Barren Land Fallow Bare soil

77 86 91 94

41. Deciduous Forest Woods Fair

36 60 73 79

71. Herbaceous Herbaceous - mixture of grass, weeds, and low-growing brush, with brush the minor element Fair

61 71 81 89

82. Cultivated Crops Row crops Contoured (poor)

70 79 84 88

90. Woody Wetlands Woods Poor

45 66 77 83

95. Emergent Herbaceous Wetlands

Woods - grass combination Poor

57 73 82 86

Basin lag times were computed using equation 11-26 from KDOT’s Design Manual which is:

𝑇𝑙𝑎𝑔 = 0.0221 [ 𝐿

√𝑆𝑙

0.66

The equation variables and values are described in Table 5. The longest flow paths with markers at 10% and 85% of the flow path length are shown on Figure 4.

Table 5. Lag Time Parameters

Basin A B C

L 1 (ft) 42,658 10,683 9,967

Sl 2 (ft/ft) 0.0044 0.0160 0.0141 1 Length of the longest flow path measured from a point on the drainage divide to the watershed outlet or design point.

2 Average slope of the longest flow path defined as the elevation difference between two points on the drainage path, located at 10% and 85% of the path length (measured from the design point), divided by the path length between the points (0.75 L).

Table 6 provides a summary of the drainage basin parameters.

Table 6. Drainage Basin Parameter Summary

Basin A B C

Area (acres) 4,781.0 314.6 285.3

RCN 78 79 80

Tlag (min) 151 39 39

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Table 7 provides an excerpt from table 11.5.3-1 of KDOT’s Design Manual and shows the recommended storm durations for design recurrence intervals.

Table 7. Storm Duration for Flood Hydrograph Simulation

Recurrence Interval (years)

Western Region Storm Duration

(hours)

2 3

5 3

10 3

25 6

50 6

100 12 Note: AMC = 2 for all recurrence intervals in the western region

Rainfall depth-duration-frequency data was obtained from KDOT’s Rainfall Intensity Tables

(2016) which were developed from the National Oceanic and Atmospheric Administration (NOAA)

Atlas 14 Volume 8. Intensities were converted to depths by multiplying by the recommended storm durations. Table 8 provides the rainfall intensities and depths for the design recurrence intervals for Phillips County, Kansas. The depths presented are within the range listed for Phillips County on the NOAA Atlas 14 point precipitation frequency estimates website.

Table 8. Rainfall Depth-Duration-Frequency Data for Phillips County, Kansas

Recurrence Interval (years)

Rainfall Intensity (inches/hour)

Rainfall Depth (inches)

10 0.95 2.85

25 0.69 4.14

The KDOT Design Manual does not specify which rainfall distribution to use, however, since

NOAA Atlas 14 rainfall depths are being used, the corresponding rainfall distribution was used instead of the SCS Type II distribution which was the previous standard. The figure presented in

Merkel et al. identifies the MSE3 rainfall distribution for Phillips County Kansas where the project is located. The latest draft version of the Storm Rainfall Depth and Distribution chapter in Part 630

Hydrology of the National Engineering Handbook confirms that the NOAA distributions should be used instead of the SCS distributions where developed. It also outlines the method that was used to extract the 3-hour, 6-hour, and 12-hour distributions needed for analysis form the 24-hr MSE3 distribution provided.

Runoff hydrographs were computed using the NRCS dimensionless unit hydrograph procedure.

Rainfall depths and distributions as well as drainage basin unit hydrographs, curve numbers, and lag times were input to HEC-HMS to calculate runoff hydrographs and develop design discharges.

Peak flows for the design 10% and 4% AEP design events for each drainage basin are presented in Table 9.

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Table 9. Peak Discharge Summery

Basin 10% AEP 4% AEP

A 1,377 cfs 2,445 cfs

B 260 cfs 450 cfs

C 250 cfs 424 cfs

Design discharges were checked using three additional methods for drainage basin A, which is the only greater than 640 acres in area:

Three-Variable Regression Equations outlined in section 11.3 of KDOT’s Design Manual

USGS Regression Method for Kansas presented in section 11.4 of KDOT’s Design

Manual

USGS SIR 2017-5063 Regression Equations

These regression equations do not apply to smaller drainage areas. The USGS regression equations presented in KDOT’s Design Manual are from a previous USGS study. The latest flood frequency regression equations presented in USGS SIR 2017-5063 were published more recently than KDOT’s Design Manual. Table 10 shows compares the peak flows calculated using these methods.

Table 10. Regression Equation Peak Discharge Summary

A

10% AEP 4% AEP

Three-Variable Regression Equations 731 cfs 1,021 cfs USGS Regression Method (KDOT’s Design Manual) 1,411 cfs 2,334 cfs USGS SIR 2017-5063 Regression Equations 486 cfs 846 cfs

3. Hydraulics

SRH-2D Model Development Sedimentation and River Hydraulics 2D model (SRH-2D), a two-dimensional depth-averaged numerical solver developed by the U.S. Bureau of Reclamation (USBR, 2008), was used to characterize hydraulic conditions at each of the three culverts undergoing replacement. Design flow hydrographs developed in the previous section for Bow Creek and the North Fork Solomon

River, as well as historical reservoir operating conditions at Kirwin reservoir, were input into an existing conditions model to estimate the impacts of tailwater controls at each culvert. An overview of the model domain is provided in Figure 5.

E Xavier Rd

S Kirwin Lake Rd

¬«9

Kirwin Reservoir

N.F. Solomon R.

Inflow BC

Bow Creek Inflow BC

Downstream Normal Depth BC

Station 136+70

Station 122+25

Station 88+32

Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community

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FIGURE 4. EXISTING CONDITIONS MODEL OVERVIEW

XAVIER ROAD

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Boundary Condition SRH-2D Model Domain

Analyzed Road Crossings !. Culvert Replacement

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Model inputs for the existing conditions model include a computational mesh to represent the topography and land cover characteristics of the project along with discharge data and boundary conditions.

A computational mesh was generated using aerial photography, land cover/land use data, topographic data, and project design files.

The best available elevation data was assigned to the mesh. A 1-meter digital elevation model (DEM) published in 2017 from high resolution LiDAR source data was obtained from the USGS. Additionally, survey data was taken to capture topography and roadway elevations at the three analyzed road crossings shown in Figure 5. Since data was only taken down to the water surface at these three locations, the DEM was used to model terrain and stream bathymetry in SRH-2D.

Spatial varying surface roughness information was incorporated into the model using aerial photographs and land cover/land use coverage available through the National Land

Cover Dataset (NLCD). The model applied manning’s n values recommended by NRCS-

Kansas (NRCS, 2016) based on the 2011 NLCD classifications.

The initial and downstream boundary conditions were set as Kirwin Reservoir’s normal operating water level of 1729.3’ (NAVD 88). Daily reservoir inflow, discharge, and forebay elevation for the past 25 years from U.S. Bureau of Reclamation were reviewed and are presented in Figure 6. During this period, reservoir levels only exceeded the normal operating level for short durations after large inflow events. The maximum recorded elevation during the period of review was 1735.6’ which is well below the flood stage elevation of 1757.3’. The model assumed no outflow from the reservoir to be conservative.

Figure 6. Kirwin Reservoir 25 Year Water Levels

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The existing conditions model was used to develop separate proposed conditions models at each of the three roadway crossings. This allowed for higher resolution (e.g. smaller mesh cell sizes) in the vicinity of the culverts. In this case, flows developed for the culvert crossings (Basins A, B, and C) were used as inflow boundary conditions. The terrain data, land cover classifications, and downstream boundary conditions remained the same as existing. These models were used primarily to analyze shear stresses normal to the embankments during the 25-year scour design event for riprap sizing. An overview of the proposed model domains is provided in Figure 7.

HY-8 Model Development Proposed culvert sizes were developed using HY-8 software to determine the upstream headwater depth and culvert barrel flow profile for a variety of different culvert configurations. The following data was inputted into the model to size proposed culverts based on KDOT and FLH

PDDM design criteria:

10- and 25-year peak flows produced for Basins A, B, and C in Section 2

Downstream channel geometries (based on 1-m DEM)

Roadway data, including crest elevations, lengths, top widths, and surface materials

Culvert dimensions, materials, and inlet configurations

Outlet and inlet stations and invert elevations

Culverts were designed to pass the 10-year storm while maintaining 2 feet or more of freeboard and a HW/D ratio of less than 1.2. Results from the 25-year storm were used to design scour countermeasures for the roadway embankments and culvert outlets.

Service Layer Credits: Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community

Inflow BC

Downstream BC

Culvert Internal BC

Culvert Internal BC

Culvert Internal BC

Inflow BC

Inflow BC Downstream BC

Downstream BC

Station 88+32

Station 122+25

Station 136+70

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FIGURE 5. PROPOSED CONDITIONS HYDRAULICS MODELS

XAVIER ROAD

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Boundary Condition Model Domain Computational Mesh

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4. Proposed Design

Proposed Culvert Sizes The proposed culvert sizes are presented in Table 11. Based on the results of the existing conditions SRH-2D model simulation, tailwater effects from Bow Creek were assumed to be negligible for the 10-year design storm. Thus, the sizes presented in this report comply with both

KDOT and FLH design standards while assuming standard tailwater control.

Per conversations with the Bureau of Reclamation there is no known design intent towards perching the existing culverts. Since there is no upstream development and the flood stages from the reservoir overtop the roadway at each of the three culvert locations, it has been agreed upon to not incorporate perched outlets into the final design.

Table 11. Proposed Culvert Specifications

Station Type Diameter (ft) No. of

Barrels

88+32 Reinforced Concrete Pipe 6 5

122+25 Reinforced Concrete Pipe 5 2

136+70 Reinforced Concrete Pipe 5 2

Profiles and plan views of these culverts, as well as details of the flared end sections, are available in the construction plan set included with this deliverable.

HY-8 Model Results

Tables 12 and 13 provide summaries of the HY-8 model results for the proposed culvert configurations. An overview of the HY-8 model inputs and results can be found in Appendix B.

Table 12. 10-Year Design Event HY-8 Model Results

Station Culvert

Discharge (cfs)

Overtopping Discharge

(cfs)

Roadway Elevation

(ft)

Headwater Elevation

(ft) HW/D Ratio

88+32 1377 0 1736.4 1732.1 1.18

122+25 260 0 1746.5 1739.8 0.95

136+70 250 0 1741.8 1736.4 0.94

Table 13. 25-Year Flood Event HY-8 Model Results

Station Culvert

Discharge (cfs)

Overtopping Discharge

(cfs)

Roadway Elevation

(ft)

Headwater Elevation

(ft)

88+32 1984 461 1736.4 1736.9

122+25 450 0 1746.5 1742.3

136+70 424 0 1741.8 1738.6

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Culvert Outlet Protection As the local Kansas DOT does not provide detail for riprap aprons for culverts larger than 48-inches, the Urban Drainage and Flood Control District Culvert Design tool (UDFCD, 2017) was used to design outlet protection for the proposed culverts. The publically available UDFCD Culvert

Design tool simplifies the design procedure by recommending an appropriate riprap apron configuration based on a set of inputs similar to those required by HY-8. The project site being rather remote with weight restricted roadways presented the opportunity to specify the riprap aprons such that the size of riprap was consistent between all three locations. Thus, the outlet protection at station 88+32 was upsized from Class III (based on the results of the analysis) to

Class V to maintain a consistent riprap size. As an additional conservative measure the maximum allowable channel velocity of 7 ft/s was used based on the non-cohesive soils found at the project site.

Preliminary recommendations based on the 25-year flood event results of this analysis are summarized in Table 14. An overview of the UDFCD Culvert Design tool model inputs and results can be found in Appendix C. Note the design apron width differs from the minimum width recommended by UDFCD in order to accommodate a 3:1 flare angle as recommended by FHWA guidance for standard culvert riprap aprons (U.S. Customary Detail C251-50).

Table 14. Riprap Apron Design Summary

Station Riprap Class

Nominal Riprap

Size (D50) (in)

Minimum Thickness of Riprap Layer (in)

Apron Length

(ft)

Single Culvert Apron Width

(ft)

Design Apron

Width (ft)

88+32 V 18 39 32 13 78

122+25 V 18 39 50 16 53

136+70 V 18 39 46 16 50

Embankment Protection Per conversations with the Kirwin National Wildlife Refuge, it is recommended that the embankments be armored to reduce the risk of roadway failure. To do so, the embankment protection was sized using the results of the 2D hydraulic model results, namely shear stresses normal to the embankment during the 25-year flood event. As with the outlet protection, remote site conditions warranted using limited variation in materials, thus the same size stone will be used at all three locations. Station 88+32, which experiences a shear stress range of 4-6 psf during overtopping based on proposed conditions model results for the 25-year flood, requires a

Class III riprap for slope protection. As the roadway embankment at stations 122+25 and 136+70 could be overtopped in flood events greater than the 25-year storm, these embankments also show slope protection with Class III riprap.

Figure 8 provides the 25-year maximum shear stress profile normal to embankment station

88+32.

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Figure 8. 25-Year Shear Stress Profile for Embankment Station 88+32

Riprap will be placed along the downstream and upstream toe, face and shoulder of the embankment at Station 88+32 to protect against both submerged and free flow regimes. Since the embankment is not expected to overtop at Stations 122+25 and 136+70 for the 25-year event, riprap will only be placed along the downstream toe, face and shoulder as a precautionary countermeasure. Additional toe protection will also be included below grade at all three embankments.

Preliminary recommendations are summarized in Table 13.

Table 13. Embankment Riprap Design for Overtopping Summary

Station Nominal Riprap Size

(D50) (in) Riprap Class

Minimum Thickness of Riprap Layer (in)

88+32 12 III 27

122+25 12 III 27

136+70 12 III 27

5. Conclusion As part of the proposed improvements to roads within the Kirwin National Wildlife Refuge a hydrologic and hydraulic analysis was performed to appropriately size three culvert replacement locations along South Side Drive. Culverts have been designed to pass the 10-year storm while maintaining 2 feet or more of freeboard and a HW/D ratio of less than 1.2. Results from the 25-

0 20 40 60 80 100

E m b a n k m e n t

E le v a ti o n ft

S h e a r S tr e s s lb

/f t2

Distance (ft)

Shear Stress Profile Embankment Profile

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Recommendations Report year storm were used to design scour countermeasures for the roadway embankments and culvert outlets.

6. References Federal Lands Highway Division, "Project Development and Design Manual", Chapter 7

Hydrology and Hydraulics, December 2012.

Kansas Department of Transportation, Bureau of Road Design, “Design Manual”, Volume I (Part

C) Elements of Drainage & Culvert Design, December 2016.

Kansas Department of Transportation, Bureau of Road Design, “Rainfall Intensity Tables”, Road

Memorandum No. 16-03, September 2016.

Kansas Department of Transportation, “Functional Classification Map of Phillips County 74”, June

2013.

Merkel, W., and Fox Moody, H., “NOAA Atlas 14 rainfall for Midwest and Southeast states”, April

2015.

NRCS-Kansas., “Manning’s n Values for Various Land Covers to Use for Dam Breach Analyses by NRCS in Kansas”, adopted by State Conservation Engineer Curtis Janssen, July 2016.

Painter, C.C., Heimann, D.C., and Lanning-Rush, J.L., “Methods for estimating annual exceedance-probability streamflows for streams in Kansas based on data through water year 2015”, U.S. Geological Survey Scientific Investigations Report 2017–5063 ver. 1.1, September 2017, https://doi.org/10.3133/sir20175063.

Urban Drainage and Flood Control District, “Culvert Design – UD-Culvert v3.05”, 2017.

U.S. Bureau of Reclamation, “Sedimentation and River Hydraulics 2D Model”, 2008.

U.S. Department of Agriculture, Natural Resources Conservation Service, “National Engineering

Handbook”, Part 630 Hydrology, Chapter 4 Storm Rainfall Depth and Distribution, September 2015, Draft.

7. Appendices

Appendix A – NRCS Soil Surveys

Appendix B – HY-8 Model Inputs and Results

Appendix C – UDFCD Culvert Design Tool Inputs and Results

Appendix A

NRCS Soil Surveys

Hydrologic Soil Group—Phillips County, Kansas, and Rooks County, Kansas

Natural Resources Conservation Service

Web Soil Survey National Cooperative Soil Survey

9/16/2019

483000 484000 485000 486000 487000 488000

483000 484000 485000 486000 487000 488000

39° 38' 8'' N

2'

2' ' W

39° 38' 8'' N

' 5 2'

' W

39° 33' 21'' N

2'

2' ' W

39° 33' 21'' N

' 5 2'

' W

N

Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 14N WGS84 0 2000 4000 8000 12000

Feet 0 500 1000 2000 3000

Meters Map Scale: 1:43,200 if printed on A portrait (8.5" x 11") sheet.

MAP LEGEND MAP INFORMATION

Area of Interest (AOI) Area of Interest (AOI)

Soils Soil Rating Polygons

A

A/D

B

B/D

C

C/D

D

Not rated or not available

Soil Rating Lines A

A/D

B

B/D

C

C/D

D

Not rated or not available

Soil Rating Points A

A/D

B

B/D

C

C/D

D

Not rated or not available

Water Features Streams and Canals

Transportation Rails

Interstate Highways

US Routes

Major Roads

Local Roads

Background Aerial Photography

The soil surveys that comprise your AOI were mapped at 1:24,000.

Please rely on the bar scale on each map sheet for map measurements.

Source of Map: Natural Resources Conservation Service Web Soil Survey URL:

Coordinate System: Web Mercator (EPSG:3857)

Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required.

This product is generated from the USDA-NRCS certified data as of the version date(s) listed below.

Soil Survey Area: Phillips County, Kansas Survey Area Data: Version 16, Sep 12, 2018

Soil Survey Area: Rooks County, Kansas Survey Area Data: Version 20, Sep 12, 2018

Your area of interest (AOI) includes more than one soil survey area. These survey areas may have been mapped at different scales, with a different land use in mind, at different times, or at different levels of detail. This may result in map unit symbols, soil properties, and interpretations that do not completely agree across soil survey area boundaries.

Soil map units are labeled (as space allows) for map scales 1:50,000 or larger.

Date(s) aerial images were photographed: Jun 21, 2011—Sep 27, 2017

The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident.

Hydrologic Soil Group—Phillips County, Kansas, and Rooks County, Kansas

Natural Resources Conservation Service

Web Soil Survey National Cooperative Soil Survey

9/16/2019

Hydrologic Soil Group

Map unit symbol Map unit name Rating Acres in AOI Percent of AOI

2202 Munjor sandy loam, occasionally flooded

A 377.3 3.9%

2234 Roxbury silt loam, channeled

B 61.7 0.6%

2236 Roxbury silt loam, occasionally flooded

B 260.5 2.7%

2347 McCook silt loam, rarely flooded

B 40.1 0.4%

2375 Roxbury silt loam, rarely flooded

B 1,472.5 15.3%

2519 Armo loam, 3 to 7 percent slopes

B 449.0 4.7%

2547 Brownell-Heizer gravelly loams, 3 to 30 percent slopes

C 315.1 3.3%

2612 Harney silt loam, 0 to 1 percent slopes

C 39.1 0.4%

2674 Holdrege silt loam, 1 to 3 percent slopes, plains and breaks

C 1,341.7 14.0%

2817 Uly silt loam, 3 to 6 percent slopes

B 619.6 6.5%

2819 Uly silt loam, 6 to 11 percent slopes

B 925.9 9.6%

2820 Uly silt loam, 6 to 11 percent slopes, eroded

B 715.4 7.4%

2949 Wakeen-Nibson complex, 5 to 20 percent slopes

C 2,206.3 23.0%

Subtotals for Soil Survey Area 8,824.0 91.9%

Totals for Area of Interest 9,604.9 100.0%

Map unit symbol Map unit name Rating Acres in AOI Percent of AOI

2236 Roxbury silt loam, occasionally flooded

B 20.2 0.2%

2612 Harney silt loam, 0 to 1 percent slopes

C 17.4 0.2%

2674 Holdrege silt loam, 1 to 3 percent slopes, plains and breaks

C 162.0 1.7%

Hydrologic Soil Group—Phillips County, Kansas, and Rooks County, Kansas

Natural Resources Conservation Service

Web Soil Survey National Cooperative Soil Survey

Map unit symbol Map unit name Rating Acres in AOI Percent of AOI

2675 Holdrege silt loam, 3 to 7 percent slopes, plains and breaks

C 20.9 0.2%

2817 Uly silt loam, 3 to 6 percent slopes

B 140.3 1.5%

2819 Uly silt loam, 6 to 11 percent slopes

B 143.0 1.5%

2820 Uly silt loam, 6 to 11 percent slopes, eroded

B 36.7 0.4%

2949 Wakeen-Nibson complex, 5 to 20 percent slopes

C 221.6 2.3%

2953 Wakeen silt loam, 3 to 7 percent slopes

C 18.7 0.2%

Subtotals for Soil Survey Area 780.8 8.1%

Totals for Area of Interest 9,604.9 100.0%

Hydrologic Soil Group—Phillips County, Kansas, and Rooks County, Kansas

Natural Resources Conservation Service

Web Soil Survey National Cooperative Soil Survey

Appendix B

HY-8 Model Inputs and Results

Table 1 - Summary of Culvert Flows at Crossing: Station 136+70 Headwater Elevation (ft)

Discharge Names Total Discharge (cfs)

2x60" RCP Discharge (cfs)

Roadway Discharge (cfs)

Iterations

1736.38 10-Year 250.00 250.00 0.00 1

1738.63 25-Year 424.00 424.00 0.00 1

1741.80 Overtopping 603.62 603.62 0.00 Overtopping

Table 2 - Culvert Summary Table: 2x60" RCP Discharge

Names 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)

10-Year 250.00 250.00 1736.38 4.680 1.488 1-S2n 2.662 3.195 2.860 1.838 10.433

25-Year 424.00 424.00 1738.63 6.928 6.728 5-S2n 3.922 4.139 4.043 2.254 12.173

Table 3 - Summary of Culvert Flows at Crossing: Station 88+32

Elevation (ft)

Discharge Names Total Discharge (cfs)

5x72" Discharge (cfs)

Roadway Discharge (cfs)

Iterations

1732.05 10-Year 1377.00 1377.00 0.00 1

1736.89 25-Year 2445.00 2343.29 101.61 8

1736.40 Overtopping 2261.16 2261.16 0.00 Overtopping

Table 4 - Culvert Summary Table: 5x72"

Names 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)

10-Year 1377.00 1377.00 1732.05 7.052 6.863 5-S2n 3.774 4.543 4.135 3.576 12.880

25-Year 2445.00 2343.29 1736.89 11.890 11.188 7-M2c 6.000 5.590 5.590 4.682 17.082

Table 5 - Summary of Culvert Flows at Crossing: Station 122+25

Elevation (ft)

Discharge Names Total Discharge (cfs)

2x60" RCP Discharge (cfs)

Roadway Discharge (cfs)

Iterations

1739.75 10-Year 260.00 260.00 0.00 1

1742.28 25-Year 450.00 450.00 0.00 1

1746.50 Overtopping 672.28 672.28 0.00 Overtopping

Table 6 - Culvert Summary Table: 2x60" RCP

Names 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)

10-Year 260.00 260.00 1739.75 4.746 2.749 1-S2n 1.953 3.260 2.351 1.844 13.858

25-Year 450.00 450.00 1742.28 7.280 6.084 5-S2n 2.680 4.246 3.278 2.383 16.016

Appendix C

UDFCD Culvert Design Tool Inputs and Results

Project:

Basin ID:

Soil Type:

Design Information (Input):

Design Discharge Q = 1800 cfs

Circular Culvert:

Barrel Diameter in Inches D = 72 inches

Inlet Edge Type (Choose from pull-down list)

Box Culvert: OR

Barrel Height (Rise) in Feet Height (Rise) = ft

Barrel Width (Span) in Feet Width (Span) = ft

Inlet Edge Type (Choose from pull-down list)

Number of Barrels No = 5

Inlet Elevation Elev IN = 1725 ft

Outlet Elevation OR Slope So = 0.01 ft/ft

Culvert Length L = 25 ft

Manning's Roughness n = 0.015

Bend Loss Coefficient kb = 0

Exit Loss Coefficient kx = 1

Tailwater Surface Elevation Elev Yt = 1730 ft

Max Allowable Channel Velocity V = 7 ft/s

Required Protection (Output):

Tailwater Surface Height Yt = 5.25 ft

Flow Area at Max Channel Velocity At = 64.29 ft

Culvert Cross Sectional Area Available A = 28.27 ft

Entrance Loss Coefficient ke = 0.20

Friction Loss Coefficient kf = 0.10

Sum of All Losses Coefficients ks = 1.30 ft

Culvert Normal Depth Yn = 4.03 ft

Culvert Critical Depth Yc = 5.53 ft

Tailwater Depth for Design d = 5.77 ft

Adjusted Diameter OR Adjusted Rise Da = - ft

Expansion Factor 1/(2*tan(Θ)) = 5.05

Flow/Diameter 2.5

OR Flow/(Span * Rise 1.5

) Q/D^2.5 = 5.10 ft 0.5

/s

Froude Number Fr = - Pressure flow!

Tailwater/Adjusted Diameter OR Tailwater/Adjusted Rise Yt/D = 0.88

Inlet Control Headwater HWI = 11.33 ft

Outlet Control Headwater HWO = 10.61

Design Headwater Elevation HW = 1,736.33 ft

Headwater/Diameter OR Headwater/Rise Ratio HW/D = 1.89 HW/D > 1.5!

Minimum Theoretical Riprap Size d50 = 10 in

Nominal Riprap Size d50 = 12 in

UDFCD Riprap Type Type = M

Length of Protection Lp = 32 ft

Width of Protection T = 13 ft

Determination of Culvert Headwater and Outlet Protection

Kirwin National Wildlife Refuge

Basin A - Station 88+32

Choose One:

Sandy

Non-Sandy

Soil Type:

Supercritical Flow! Using Da to calculate protection type.

Design Information (Input):

Design Discharge Q = 450 cfs

Circular Culvert:

Barrel Diameter in Inches D = 60 inches

Inlet Edge Type (Choose from pull-down list)

Box Culvert: OR

Barrel Height (Rise) in Feet Height (Rise) = ft

Barrel Width (Span) in Feet Width (Span) = ft

Inlet Edge Type (Choose from pull-down list)

Number of Barrels No = 2

Inlet Elevation Elev IN = 1735 ft

Outlet Elevation OR Slope So = 0.03 ft/ft

Culvert Length L = 52 ft

Manning's Roughness n = 0.015

Bend Loss Coefficient kb = 0

Exit Loss Coefficient kx = 1

Tailwater Surface Elevation Elev Yt = 1737.5 ft

Max Allowable Channel Velocity V = 7 ft/s

Required Protection (Output):

Tailwater Surface Height Yt = 4.06 ft

Flow Area at Max Channel Velocity At = 64.29 ft

Culvert Cross Sectional Area Available A = 28.27 ft

Entrance Loss Coefficient ke = 0.20

Friction Loss Coefficient kf = 0.20

Sum of All Losses Coefficients ks = 1.40 ft

Culvert Normal Depth Yn = 3.72 ft

Culvert Critical Depth Yc = 5.53 ft

Tailwater Depth for Design d = 5.77 ft

Adjusted Diameter OR Adjusted Rise Da = 4.86 ft

Expansion Factor 1/(2*tan(Θ)) = 5.05

Flow/Diameter 2.5

OR Flow/(Span * Rise 1.5

) Q/D^2.5 = 5.10 ft 0.5

/s

Froude Number Fr = 2.42 Supercritical!

Tailwater/Adjusted Diameter OR Tailwater/Adjusted Rise Yt/D = 0.84

Inlet Control Headwater HWI = 11.27 ft

Outlet Control Headwater HWO = 9.70

Design Headwater Elevation HW = 1,746.27 ft

Headwater/Diameter OR Headwater/Rise Ratio HW/D = 1.88 HW/D > 1.5!

Minimum Theoretical Riprap Size d50 = 14 in

Nominal Riprap Size d50 = 18 in

UDFCD Riprap Type Type = H

Length of Protection Lp = 50 ft

Width of Protection T = 16 ft

Determination of Culvert Headwater and Outlet Protection

Kirwin National Wildlife Refuge

Basin B - Station 122+25

Choose One:

Soil Type:

Supercritical Flow! Using Da to calculate protection type.

Design Information (Input):

Design Discharge Q = 424 cfs

Circular Culvert:

Barrel Diameter in Inches D = 60 inches

Inlet Edge Type (Choose from pull-down list)

Box Culvert: OR

Barrel Height (Rise) in Feet Height (Rise) = ft

Barrel Width (Span) in Feet Width (Span) = ft

Inlet Edge Type (Choose from pull-down list)

Number of Barrels No = 2

Inlet Elevation Elev IN = 1731.73 ft

Outlet Elevation OR Slope So = 0.01 ft/ft

Culvert Length L = 40 ft

Manning's Roughness n = 0.015

Bend Loss Coefficient kb = 0

Exit Loss Coefficient kx = 1

Tailwater Surface Elevation Elev Yt = ft

Max Allowable Channel Velocity V = 7 ft/s

Required Protection (Output):

Tailwater Surface Height Yt = 2.00 ft

Flow Area at Max Channel Velocity At = 30.29 ft

Culvert Cross Sectional Area Available A = 19.63 ft

Entrance Loss Coefficient ke = 0.20

Friction Loss Coefficient kf = 0.19

Sum of All Losses Coefficients ks = 1.39 ft

Culvert Normal Depth Yn = 3.84 ft

Culvert Critical Depth Yc = 4.14 ft

Tailwater Depth for Design d = 4.57 ft

Adjusted Diameter OR Adjusted Rise Da = 4.42 ft

Expansion Factor 1/(2*tan(Θ)) = 4.45

Flow/Diameter 2.5

OR Flow/(Span * Rise 1.5

) Q/D^2.5 = 3.79 ft 0.5

/s

Froude Number Fr = 1.18 Supercritical!

Tailwater/Adjusted Diameter OR Tailwater/Adjusted Rise Yt/D = 0.45

Inlet Control Headwater HWI = 6.93 ft

Outlet Control Headwater HWO = 6.69

Design Headwater Elevation HW = 1,738.66 ft

Headwater/Diameter OR Headwater/Rise Ratio HW/D = 1.39

Minimum Theoretical Riprap Size d50 = 16 in

Nominal Riprap Size d50 = 18 in

UDFCD Riprap Type Type = H

Length of Protection Lp = 46 ft

Width of Protection T = 16 ft

Determination of Culvert Headwater and Outlet Protection

Kirwin National Wildlife Refuge

Basin C - Station 136+70

Choose One: