FLAP_400(1)_Hydraulics_Report_wAppendix.pdf

Logandale Trails Access Road Clark County, NV

NV FLAP 400(1)

Hydraulic Report

Federal Highway Administration Central Federal Lands Highway Division

April 2, 2024 i NV FLAP 400(1) Logandale Trails –Hydraulic Report

Executive Summary

Hydrologic and hydraulic analyses were conducted for the Logandale Trails Access Road NV FLAP 400(1) project located in Clark County, NV. There are various sections on the route where the road currently functions as a low water crossing. Thirteen crossing locations were identified for detailed hydraulic analyses. Design peak flows were estimated for the project basins using regression equations and the rational method. Concrete low water crossings are recommended at three locations. For these locations the minimum length of the concrete pavement section and embankment protection was estimated using a 25-year flood. The extent of protection was adjusted to fit the site conditions. Additional locations were evaluated for improvement during project development but were excluded from the project. The remaining informal low water crossing locations will be improved by asphalt paving but will not require additional protection outside of the pavement section. The following table summarizes the minimum low water crossing locations and protection details. The limits of the concrete low water crossings shown in the plans were adjusted to better fit the roadway longitudinal profile as needed

Summary of Low Water Crossing Recommendations

Approximate Project Station

Recommended Improvements Concrete

Pavement Length (ft)

Riprap Class

45+00 Concrete low water crossing 150 3 59+60 Concrete low water crossing 60 3

138+10 Concrete low water crossing 30 3

Due to the roadway re-alignment from station 44+50 to 52+50, one culvert crossings will be required at station 50+80. The required culvert size was estimated based on a 25-year design flood and a maximum headwater to depth ratio of 1.0 due to the high sediment loads expected in these basins. Additional locations were evaluated for improvement during project development but were excluded from the project. The following table summarizes the culvert recommendations.

Summary of Culvert Recommendations

Project Station

25-year Peak Flow (cfs)

Proposed Culvert

Diameter (in) End Treatment Outlet Protection

50+83 11.5 30 Inlet and outlet end sections

Class 3 apron per Standard C251-50 ii NV FLAP 400(1) Logandale Trails –Hydraulic Report

Table of Contents 1 Project Background Information

2 Hydraulic Design Criteria

3 Hydrology

3.1 Hydrologic Setting

3.2 Available Hydrologic Data

3.3 Peak Flow Estimates

3.3.1 Regression Equation Estimates

3.3.2 Rational Method Hydrology

4 Hydraulic Analysis

4.1 Low Water Crossings

4.2 Culverts

5 Recommendations

6 References

Tables Table 1: Hydraulic Design Criteria Table 2: Project Hydrology Locations Table 3: Available Peak Streamflow Information Table 4: Regression Equation Peak Flow Estimates Table 5: 10-minute Duration Rainfall Intensity - NOAA Atlas 14 Table 6: Rational Method Peak Flow Estimates Table 7: Recommended Low Water Crossings Table 8: Culvert Recommendations

Figures

Figure 1: Project Location Map Figure 2: Project Basin Delineation

Appendices iii NV FLAP 400(1) Logandale Trails –Hydraulic Report

Appendix A: Hydrologic Analyses Appendix B: Hydraulic Analyses

Page 1 NV FLAP 400(1) Logandale Trails –Hydraulic Report

1 PROJECT BACKGROUND INFORMATION

The project is located west of Logandale in Clark County, NV along the Logandale Trails Access Rd (Route 400), see Figure 1. The proposed project includes minor grading, widening, placing aggregate base and paving 3.25 miles of road. There are three drainages where low water crossings will be constructed.

Culverts or low water crossings will be added at a few minor drainages. The road shoulder will be reinforced with barrier under the shoulder and revetment mattresses where the stream encroaches on the road. Guardrail will be added in one location. The two railroad crossings will be consolidated into one crossing, and minor improvements to the geometry will be made. The entire 3.25-mile road will be paved at 26 feet wide with 11 foot lanes and 2 foot shoulders. Safety improvements and minor grading are proposed to address sight distance issues. Signing and striping will be added per MUTCD requirements.

At the Valley of Fire parking lot, 700 feet of roadway will be converted to one-way (with two different alignments for the two directions), with two turnaround locations at either end of the one-way roads.

Figure 1: Project Location Map.

2 HYDRAULIC DESIGN CRITERIA

The Federal Lands Highway Project Development and Design Manual (PDDM) (Federal Lands Highway 2012) establishes the hydraulic design criteria. Based on the project scoping report the road has a design speed of 25 mph and a design average daily traffic (ADT) of 995 vehicles, based on these parameters the

Page 2 NV FLAP 400(1) Logandale Trails –Hydraulic Report road is classified as low standard road for hydraulic design purposes. The applicable design criteria are listed in Table 1.

Table 1: Hydraulic Design Criteria

Road Classification: Low-Standard Road Culverts:

Design Frequency Check Frequency Allowable Headwater

25-year flood Overtopping flood

Minimum of:

• Bottom of aggregate base layer

• HW/D ratio of 1.2 for D > 48", 1.5 for D ≤ 48”

• Unacceptable hazard to human life or property

Low Water Crossings (LWC) Design Frequency Stability Extent of Protection

N/A 25-year flood Minimum 2-year flood Ditches:

Design Frequency Stability Depth

10-year flood 10-year flood • New: WSEL ≤ bottom of aggregate base layer

• Existing: WSEL ≤ shoulder hinge point

3 HYDROLOGY

3.1 HYDROLOGIC SETTING

The project is located within the Anderson Wash-Muddy River Subwatershed (HUC12: 150100120904).

The Muddy River generally flows from north to south from its headwaters in the Meadow Valley Mountains to the outlet at Lake Mead. The total drainage area for the watershed is approximately 7,200 square miles.

Based on National Hydrography Dataset (NHD) information obtained from the USGS National Map (U.S.

Geological Survey 2018), there are no perennial streams within the project limits. There are three unnamed ephemeral streams that flow across the project alignment and along Logandale Trails Access Road. Based on the national land cover dataset (Multi-Resolution Land Characteristics Consortium 2018) the project basins consist primarily of grassland, shrub/scrub, and barren land. According to the NRCS Web Soil Survey (Natural Resources Conservation Service 2015) soils in the area of interest consist primarily of Rock land – St Thomas association and Badland soil units.

The detailed hydrologic evaluation focused on potential low water crossing locations, summarized in Table

2. The potential low water crossing locations were selected based on the following criteria:

• Low water crossing locations identified during scoping.

• Low water crossing or culvert locations identified during scoping.

• Potential low water crossing locations identified based on topographic information.

Page 3 NV FLAP 400(1) Logandale Trails –Hydraulic Report

Table 2: Project Hydrology Locations

Project Station Potential Improvements 24+00 Low water crossing or culvert 27+35 Low water crossing or culvert 32+20 Low water crossing or culvert 35+00 Low water crossing or culvert 39+10 Added based on topography.

45+00 Low water crossing 51+00 Proposed Culvert 52+00 Proposed Culvert 59+60 Low water crossing

138+10 Low water crossing 145+50 Low water crossing or culvert 150+50 Low water crossing or culvert 160+00 Low water crossing or culvert 171+00 Added based on topography.

Project basins for the selected locations were delineated using ArcGIS based on USGS digital elevation model (DEM) topographic information downloaded from the USGS National Map (U.S. Geological Survey 2018). The resulting basin delineation is shown in Figure 2.

Figure 2: Project Basin Delineation

Page 4 NV FLAP 400(1) Logandale Trails –Hydraulic Report

3.2 AVAILABLE HYDROLOGIC DATA

There are no US Geological Survey (USGS) peak streamflow stations within the project limits. The closest active streamflow station is located on the Muddy River approximately 3 miles north of the project site.

Table 3 summarizes the available active peak streamflow information.

Due to the size of the drainage area for the active stations compared to the project tributaries the streamflow data was not used for the project.

Table 3: Available Peak Streamflow Information

USGS

Station

Location Latitude Longitude Drainage Area Period of Record Years Status

09419000 Muddy River 36°38'35" 114°32'20" 6,780 mi2 1950-2018 69 Active

3.3 PEAK FLOW ESTIMATES

Two methods were used to estimate peak flows for the project basins. Regression equations were used for basins that met the applicability range of the equations, and the rational method was used basins outside of the range, specifically, basins smaller than 0.1 square miles. The following sections summarize the peak flow estimates. Additional details of the hydrologic analysis are provided in Appendix A.

3.3.1 Regression Equation Estimates

The peak flow regression equations for Nevada are based on USGS Water Supply Paper 2433 (Hjalmarson, Waltemeyer and Thomas 1997). The site is located in the Southern Great Basin hydrologic region (Region 10). The equations developed for Region 10 relate peak discharge to drainage area. The National Streamflow Statistics Program (U.S. Geological Survey 2017) was used to perform the peak discharge estimates. A summary of peak flow results for the selected return periods are shown in Table 4.

Table 4: Regression Equation Peak Flow Estimates

Basin ID Project Station

Area

(sq. mi.)

Peak Flow (cfs)

2-year 5-year 10-year 25-year 50-year 100-year 500-year 2735 27+35 0.13 3.7 25.5 56.5 106.0 150.0 208.0 322.0 4500 45+00 1.29 13.9 98.8 234.0 472.0 700.0 1010.0 1750.0

13810 138+10 0.17 4.3 29.9 66.7 126.0 180.0 250.0 392.0

The Southern Great Basin – Region 10 peak flow regression equations were developed using the following ranges of the predictor variables:

• Drainage area: 0.1 to 1,000 square miles

There are multiple basins within the project that are smaller than 0.1 square miles. For the basins that fall outside the applicable range of the regression equations the rational method was used to estimate peak flows as described in Section 3.3.2.

Page 5 NV FLAP 400(1) Logandale Trails –Hydraulic Report

3.3.2 Rational Method Hydrology

The rational method (Federal Highway Administration 2002) was used to estimate peak flow from the basins smaller than 0.1 square miles. A time of concentration estimate using the Kirpich equation resulted in times less than 10 minutes, therefore a minimum time of concentration of 10 minutes was assumed for all the undeveloped basins. The rainfall intensity values were obtained from NOAA Atlas 14 Volume 1 (Bonnin, et al. 2011) using the Precipitation Frequency Data Server (National Oceanic and Atmospheric Administration 2011). The 10-minute rainfall intensities for various return periods are shown in Table 5.

Table 5: 10-minute Duration Rainfall Intensity - NOAA Atlas 14

Percent Chance Exceedance (%)

Return Period (year)

Point Precipitation (inches/hour)

50 2 1.45 20 5 2.06 10 10 2.56 4 25 3.27 2 50 3.85 1 100 4.51

0.2 500 6.28

A runoff coefficient (C) of 0.25 was assumed based on undeveloped basins. Table 6 summarizes the basin parameters and peak flow results for selected return periods.

Table 6: Rational Method Peak Flow Estimates

Basin ID Project Station

Area (acres)

Peak Flow (cfs) 2-year 5-year 10-year 25-year 50-year 100-year 500-year

2400 24+00 19.1 6.9 9.8 12.2 15.6 18.4 21.6 30.0 3220 32+20 38.0 13.8 19.6 24.3 31.1 36.6 42.9 59.7 3500 35+00 27.7 10.0 14.3 17.7 22.7 26.7 31.3 43.5 3910 39+10 2.1 0.8 1.1 1.4 1.7 2.1 2.4 3.3 5100 50+80 14.1 5.1 7.2 9.0 11.5 13.5 15.8 22.1 5200 52+00 2.2 0.8 1.1 1.4 1.8 2.1 2.4 3.4 5960 59+60 11.2 4.1 5.8 7.2 9.2 10.8 12.7 17.6

14550 145+50 8.4 3.1 4.3 5.4 6.9 8.1 9.5 13.2 15050 150+50 9.9 3.6 5.1 6.3 8.1 9.5 11.1 15.5 16000 160+00 2.6 0.9 1.3 1.7 2.1 2.5 3.0 4.1 17100 171+00 10.7 3.9 5.5 6.8 8.7 10.3 12.1 16.8

Page 6 NV FLAP 400(1) Logandale Trails –Hydraulic Report

4 HYDRAULIC ANALYSIS

4.1 LOW WATER CROSSINGS

There were three concrete low water crossings (LWC) identified at scoping. Based on the results of the hydrology analysis a concrete low water crossing was also evaluated at station 27+35 but ultimately excluded from the project. The low water crossings will be unvented and constructed at grade with the upstream channel. The low water crossings will consist of a concrete pavement section with cutoff walls and riprap embankment protection both upstream and downstream. The concrete pavement section will have a reverse crown using a 1 percent slope. The low water crossing profile was obtained from the project existing survey information. Uniform flow calculations using the Hydraulic Toolbox (Federal Highway Administration 2018) were used to estimate the required concrete pavement length of the LWCs.

The length of the concrete pavement section was based on the channel top width for a 25-year flood. The minimum extent of embankment protection was estimated based on the channel top width for a 25-year flood. The required riprap class was estimated using HEC-23 (Federal Highway Administration 2009) equations for channel revetment and embankment overtopping protection. Due to the high ADT embankment protection using a minimum of Class 3 riprap is recommended. The sections below summarize the minimum requirements for the selected crossings. The limits of the concrete low water crossings shown in the plans were adjusted to better fit the roadway longitudinal profile as needed.

Additional details of the analysis can be found in Appendix B.

Table 7: Recommended Low Water Crossings

Approximate Project Station

Recommended Improvements

Minimum Concrete

Pavement Length (ft)

Adjusted Concrete Pavement Length

(ft) Riprap Class

45+00 Concrete low water crossing 98 150 3 59+60 Concrete low water crossing 16 60 3

138+10 Concrete low water crossing 35 30 3

Based on the hydrology results and findings from a site visit conducted by CFL in February 2020, there are no additional improvements for the remaining potential low water crossing locations. The crossings will be improved by paving the road, but no additional embankment protection is recommended. These crossings experience very limited occasional flow and there was no evidence of problematic erosion at these locations. Typical maintenance operations will be required in the road corridor after large storm events.

4.2 CULVERTS

Due to the roadway re-alignment from station 44+50 to 52+50, one culvert crossings will be required at stations 50+80. The required culvert size was estimated using HY-8 (Federal Highway Administration 2017) based on a 25-year design flood. The analysis was conducted assuming inlet control and a maximum headwater to depth ratio of 1.0 due to the high sediment loads expected in these basins. It is assumed

Page 7 NV FLAP 400(1) Logandale Trails –Hydraulic Report that the minimum culvert size per FLH criteria is 24-inch. The proposed culvert recommendations are shown in Table 8.

Table 8: Culvert Recommendations

Project Station

25-year Peak Flow (cfs)

Proposed Culvert

Diameter (in) End Treatment Outlet

Protection

50+80 11.5 30 Inlet and outlet end sections

Class 3 apron per Standard

C251-50

5 RECOMMENDATIONS

The minimum low water crossing recommendations are shown in Table 7 and the culvert recommendations are shown in Table 8. Refer to the project plans for construction details, final layout, extent of protection, and additional requirements.

Page 8 NV FLAP 400(1) Logandale Trails –Hydraulic Report

6 REFERENCES

Bonnin, Geoffrey M., Deborah Martin, Bingzhang Lin, Tye Parzybok, Michael Yekta, and David Riley. 2011.

"Precipitation-Frequency Atlas of the United States, Semiarid Southwest (Arizona, Southeast California, Nevada, New Mexico, Utah)." NOAA Atlas 14, Volume 1, National Oceanic and Atmospheric Administration , Silver Springs, MD.

Federal Highway Administration . 2009. "Bridge Scour and Stream Instability Countermeasures - Experience, Selection, and Design Guidelines, Hydraulic Engineering Circular No. 23, Third Edition, FHWA-NHI 09-111 (Vol. 1), FHWA-NHI-09-112 (Vol. 2)." Federal Highway Administration, Washington, DC.

Federal Highway Administration. 2017. HY-8 Culvert Analysis Program. Version 7.50.

Federal Highway Administration. 2002. Hydraulic Design Series No. 2, Second Edition, FHWA -NHI-02-001.

Washington, DC: Federal Highway Administration.

Federal Highway Administration. 2018. Hydraulic Toolbox. Version 4.4.

Federal Lands Highway. 2012. "Project Development and Design Manual, Chapter 7 Hydrology and Hydraulics." https://flh.fhwa.dot.gov/resources/design/pddm/.

Hjalmarson, H.W., S.D. Waltemeyer, and Blakemore E Thomas. 1997. "Methods for Estimating Magnitude and Frequency of Floods in the Southwestern United States." U.S. Geological Survey Water Supply Paper 2433.

Multi-Resolution Land Characteristics Consortium . 2018. National Land Cover Database 2011 (NLCD 2011). Multi-Resolution Land Characteristics Consortium (MRLC).

https://data.nal.usda.gov/dataset/national-land-cover-database-2011-nlcd-2011.

National Oceanic and Atmospheric Administration. 2011. Precipitation Frequency Data Server (PFDS).

Silver Springs, MD. Accessed April 2019. https://hdsc.nws.noaa.gov/hdsc/pfds/index.html.

Natural Resources Conservation Service. 2015. Soil Survey Geographic (SSURGO) database. Fort Worth, TX. http://websoilsurvey.nrcs.usda.gov.

U.S. Geological Survey. 2018. The National Map. Accessed March 2019.

https://viewer.nationalmap.gov/advanced-viewer/.

U.S. Geological Survey. 2017. The National Streamflow Statistics Program (NSS) Version 6.

NV FLAP 400(1) Logandale Trails –Hydraulic Report

Appendix A – Hydrologic Analyses

10/29/2019 Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=36.6034&lon=-114.5161&data=intensity&units=english&series=pds 1/6

NOAA Atlas 14, Volume 1, Version 5 Location name: Overton, Nevada, USA*

Latitude: 36.6034°, Longitude: -114.5161° Elevation: 1726.11 ft**

* source: ESRI Maps ** source: USGS

POINT PRECIPITATION FREQUENCY ESTIMATES

Sanja Perica, Sarah Dietz, Sarah Heim, Lillian Hiner, Kazungu Maitaria, Deborah Martin, Sandra Pavlovic, Ishani Roy, Carl Trypaluk, Dale Unruh, Fenglin Yan, Michael Yekta, Tan Zhao, Geoffrey

Bonnin, Daniel Brewer, Li-Chuan Chen, Tye Parzybok, John Yarchoan

NOAA, National Weather Service, Silver Spring, Maryland

PF_tabular | PF_graphical | Maps_&_aerials

PF tabular PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches/hour)1

Duration Average recurrence interval (years)

1 2 5 10 25 50 100 200 500 1000

5-min 1.45 (1.19‑1.75)

1.91 (1.57‑2.33)

2.70 (2.21‑3.31)

3.36 (2.72‑4.09)

4.30 (3.43‑5.22)

5.06 (4.02‑6.17)

5.93 (4.60‑7.24)

6.85 (5.20‑8.42)

8.24 (6.12‑10.2)

9.42 (6.83‑11.8)

10-min 1.10 (0.906‑1.33)

1.45 (1.19‑1.78)

2.06 (1.67‑2.52)

2.56 (2.08‑3.11)

3.27 (2.62‑3.98)

3.85 (3.06‑4.69)

4.51 (3.50‑5.50)

5.22 (3.95‑6.41)

6.28 (4.66‑7.79)

7.17 (5.20‑9.01)

15-min 0.908 (0.744‑1.10)

1.20 (0.988‑1.46)

1.70 (1.38‑2.08)

2.12 (1.72‑2.57)

2.70 (2.16‑3.28)

3.18 (2.53‑3.88)

3.73 (2.89‑4.55)

4.31 (3.27‑5.30)

5.19 (3.85‑6.44)

5.92 (4.30‑7.45)

30-min 0.614 (0.502‑0.740)

0.806 (0.664‑0.986)

1.15 (0.932‑1.40)

1.42 (1.16‑1.73)

1.82 (1.45‑2.21)

2.14 (1.70‑2.61)

2.51 (1.95‑3.06)

2.90 (2.20‑3.57)

3.49 (2.59‑4.33)

3.99 (2.89‑5.01)

60-min 0.379 (0.311‑0.458)

0.498 (0.412‑0.611)

0.709 (0.577‑0.867)

0.882 (0.715‑1.07)

1.13 (0.900‑1.37)

1.33 (1.05‑1.62)

1.55 (1.21‑1.90)

1.80 (1.36‑2.21)

2.16 (1.60‑2.68)

2.47 (1.79‑3.10)

2-hr 0.228 (0.187‑0.276)

0.294 (0.244‑0.360)

0.403 (0.330‑0.495)

0.494 (0.402‑0.606)

0.623 (0.501‑0.762)

0.728 (0.576‑0.890)

0.842 (0.658‑1.03)

0.966 (0.739‑1.19)

1.15 (0.856‑1.42)

1.30 (0.946‑1.63)

3-hr 0.174 (0.144‑0.211)

0.223 (0.184‑0.274)

0.304 (0.249‑0.374)

0.366 (0.301‑0.450)

0.452 (0.366‑0.552)

0.521 (0.418‑0.642)

0.594 (0.470‑0.735)

0.673 (0.524‑0.834)

0.783 (0.595‑0.978)

0.883 (0.659‑1.11)

6-hr 0.106 (0.089‑0.129)

0.136 (0.115‑0.167)

0.184 (0.155‑0.225)

0.220 (0.185‑0.269)

0.271 (0.225‑0.331)

0.309 (0.253‑0.379)

0.351 (0.284‑0.431)

0.393 (0.312‑0.485)

0.454 (0.352‑0.566)

0.502 (0.381‑0.633)

12-hr 0.062 (0.053‑0.073)

0.080 (0.068‑0.094)

0.107 (0.092‑0.127)

0.127 (0.108‑0.150)

0.153 (0.130‑0.181)

0.173 (0.145‑0.204)

0.193 (0.160‑0.229)

0.213 (0.174‑0.255)

0.239 (0.191‑0.289)

0.259 (0.205‑0.318)

24-hr 0.035 (0.030‑0.040)

0.045 (0.039‑0.052)

0.061 (0.053‑0.071)

0.072 (0.062‑0.083)

0.087 (0.074‑0.100)

0.097 (0.083‑0.112)

0.108 (0.091‑0.125)

0.119 (0.099‑0.138)

0.132 (0.109‑0.155)

0.142 (0.117‑0.168)

2-day 0.018 (0.016‑0.021)

0.024 (0.021‑0.028)

0.032 (0.028‑0.037)

0.038 (0.033‑0.044)

0.046 (0.039‑0.053)

0.051 (0.044‑0.059)

0.057 (0.048‑0.066)

0.062 (0.052‑0.072)

0.069 (0.057‑0.081)

0.074 (0.061‑0.087)

3-day 0.013 (0.011‑0.015)

0.017 (0.015‑0.019)

0.023 (0.020‑0.026)

0.027 (0.023‑0.031)

0.032 (0.028‑0.037)

0.036 (0.031‑0.041)

0.040 (0.034‑0.046)

0.043 (0.037‑0.050)

0.048 (0.040‑0.056)

0.052 (0.043‑0.061)

4-day 0.010 (0.009‑0.011)

0.013 (0.011‑0.015)

0.018 (0.015‑0.020)

0.021 (0.018‑0.024)

0.025 (0.022‑0.029)

0.028 (0.024‑0.032)

0.031 (0.027‑0.036)

0.034 (0.029‑0.039)

0.038 (0.032‑0.044)

0.040 (0.034‑0.048) https://www.commerce.gov/ http://www.noaa.gov/ https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=36.6034&lon=-114.5161&data=intensity&units=english&series=pds 2/6

7-day 0.006 (0.006‑0.007)

0.008 (0.007‑0.010)

0.011 (0.010‑0.013)

0.013 (0.012‑0.015)

0.016 (0.014‑0.018)

0.018 (0.015‑0.020)

0.019 (0.017‑0.022)

0.021 (0.018‑0.025)

0.023 (0.020‑0.027)

0.025 (0.021‑0.029)

10-day 0.005 (0.004‑0.005)

0.006 (0.005‑0.007)

0.008 (0.007‑0.010)

0.010 (0.009‑0.011)

0.012 (0.010‑0.013)

0.013 (0.011‑0.015)

0.014 (0.012‑0.016)

0.015 (0.013‑0.018)

0.017 (0.014‑0.019)

0.018 (0.015‑0.021)

20-day 0.003 (0.002‑0.003)

0.004 (0.003‑0.004)

0.005 (0.004‑0.006)

0.006 (0.005‑0.007)

0.007 (0.006‑0.008)

0.008 (0.007‑0.009)

0.009 (0.007‑0.010)

0.009 (0.008‑0.011)

0.010 (0.009‑0.012)

0.011 (0.009‑0.013)

30-day 0.002 (0.002‑0.002)

0.003 (0.002‑0.003)

0.004 (0.003‑0.005)

0.005 (0.004‑0.005)

0.006 (0.005‑0.007)

0.006 (0.006‑0.007)

0.007 (0.006‑0.008)

0.008 (0.007‑0.009)

0.009 (0.007‑0.010)

0.009 (0.008‑0.011)

45-day 0.002 (0.001‑0.002)

0.002 (0.002‑0.002)

0.003 (0.003‑0.003)

0.004 (0.003‑0.004)

0.004 (0.004‑0.005)

0.005 (0.004‑0.006)

0.006 (0.005‑0.007)

0.006 (0.005‑0.007)

0.007 (0.006‑0.008)

0.008 (0.006‑0.009)

60-day 0.001 (0.001‑0.001)

0.002 (0.001‑0.002)

0.002 (0.002‑0.003)

0.003 (0.003‑0.003)

0.004 (0.003‑0.004)

0.004 (0.004‑0.005)

0.005 (0.004‑0.006)

0.005 (0.004‑0.006)

0.006 (0.005‑0.007)

0.007 (0.005‑0.008)

1 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS).

Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates (for a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values.

Please refer to NOAA Atlas 14 document for more information.

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PF graphical https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=36.6034&lon=-114.5161&data=intensity&units=english&series=pds 3/6

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Maps & aerials

Small scale terrain https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=36.6034&lon=-114.5161&data=intensity&units=english&series=pds 4/6

Large scale terrain

Large scale map

3km

2mi

100km

60mi https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=36.6034&lon=-114.5161&data=intensity&units=english&series=pds 5/6

Large scale aerial

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100km

60mi

100km

60mi https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=36.6034&lon=-114.5161&data=intensity&units=english&series=pds 6/6

US Department of Commerce National Oceanic and Atmospheric Administration

National Weather Service National Water Center

1325 East West Highway Silver Spring, MD 20910

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Regression Equation Peak Flow Estimates Southwestern United States Region 10 ‐ Great Basin

2‐year 5‐year 10‐year 25‐year 50‐year 100‐year 500‐year

2735 27+35 0.13 3.7 25.5 56.5 106.0 150.0 208.0 322.0 LWC

4500 45+00 1.29 13.9 98.8 234.0 472.0 700.0 1010.0 1750.0 LWC 1

13810 138+10 0.17 4.3 29.9 66.7 126.0 180.0 250.0 392.0 LWC 3

Remarks

Blakemore E. Thomas, H.W. Hjalmarson, S.D. Waltemeyer. 1997. "Methods for Estimating Magnitude and Frequency of Floods in the Southwestern United States." U.S. Geological Survey Water Supply Paper 2433. https://pubs.usgs.gov/wsp/2433/report.pdf.

Approximate Station

Peak Flow (cfs)Basin ID Drainage Area (mi2)

Rational Method Peak Flow Estimates

2‐year 5‐year 10‐year 25‐year 50‐year 100‐year 500‐year 2‐year 5‐year 10‐year 25‐year 50‐year 100‐year 500‐year

2400 24+00 19.1 10 0.25 1.45 2.06 2.56 3.27 3.85 4.51 6.28 6.9 9.8 12.2 15.6 18.4 21.6 30.0 LWC or Culvert 3220 32+20 38.0 10 0.25 1.45 2.06 2.56 3.27 3.85 4.51 6.28 13.8 19.6 24.3 31.1 36.6 42.9 59.7 LWC or Culvert 3500 35+00 27.7 10 0.25 1.45 2.06 2.56 3.27 3.85 4.51 6.28 10.0 14.3 17.7 22.7 26.7 31.3 43.5 LWC or Culvert 3910 39+10 2.1 10 0.25 1.45 2.06 2.56 3.27 3.85 4.51 6.28 0.8 1.1 1.4 1.7 2.1 2.4 3.3 Added TBD 5100 51+00 14.1 10 0.25 1.45 2.06 2.56 3.27 3.85 4.51 6.28 5.1 7.2 9.0 11.5 13.5 15.8 22.1 Culvert 5200 52+00 2.2 10 0.25 1.45 2.06 2.56 3.27 3.85 4.51 6.28 0.8 1.1 1.4 1.8 2.1 2.4 3.4 Culvert 5960 59+60 11.2 10 0.25 1.45 2.06 2.56 3.27 3.85 4.51 6.28 4.1 5.8 7.2 9.2 10.8 12.7 17.6 LWC 2 14550 145+50 8.4 10 0.25 1.45 2.06 2.56 3.27 3.85 4.51 6.28 3.1 4.3 5.4 6.9 8.1 9.5 13.2 LWC or Culvert 15050 150+50 9.9 10 0.25 1.45 2.06 2.56 3.27 3.85 4.51 6.28 3.6 5.1 6.3 8.1 9.5 11.1 15.5 LWC or Culvert 16000 160+00 2.6 10 0.25 1.45 2.06 2.56 3.27 3.85 4.51 6.28 0.9 1.3 1.7 2.1 2.5 3.0 4.1 LWC or Culvert 17100 171+00 10.7 10 0.25 1.45 2.06 2.56 3.27 3.85 4.51 6.28 3.9 5.5 6.8 8.7 10.3 12.1 16.8 Added TBD

RemarksBasin ID Runoff

Coefficient

Peak Flow (cfs) Drainage Area

(acres)

10‐min Rainfall Intensity (in/hr) Approximate

Station

Time of Concentration

(min)

NV FLAP 400(1) Logandale Trails –Hydraulic Report

Appendix B - Hydraulic Analyses

Hydraulic Analysis Report

Project Data

Project Title: NV FLAP 400(1) Logandale

Designer: CFL

Project Date: September 1, 2021

Project Units: U.S. Customary Units

Notes: 25-Year LWC Analysis

Channel Analysis: 27+35

Notes:

Input Parameters

Channel Type: Trapezoidal

Side Slope 1 (Z1): 142.9000 ft/ft

Side Slope 2 (Z2): 21.7000 ft/ft

Channel Width: 10.0000 ft

Longitudinal Slope: 0.0100 ft/ft

Manning's n: 0.0120

Flow: 106.0000 cfs

Result Parameters

Depth: 0.4531 ft

Area of Flow: 21.4292 ft^2

Wetted Perimeter: 84.5962 ft

Hydraulic Radius: 0.2533 ft

Average Velocity: 4.9465 ft/s

Top Width: 84.5842 ft

Froude Number: 1.7319

Critical Depth: 0.5774 ft

Critical Velocity: 3.1920 ft/s

Critical Slope: 0.0031 ft/ft

Critical Top Width: 105.03 ft

Calculated Max Shear Stress: 0.2827 lb/ft^2

Calculated Avg Shear Stress: 0.1581 lb/ft^2

Channel Analysis: 45+00

Input Parameters

Channel Type: Trapezoidal

Side Slope 1 (Z1): 14.3000 ft/ft

Side Slope 2 (Z2): 70.6000 ft/ft

Channel Width: 10.0000 ft

Longitudinal Slope: 0.0100 ft/ft

Manning's n: 0.0120

Flow: 472.0000 cfs

Result Parameters

Depth: 1.0318 ft

Area of Flow: 55.5103 ft^2

Wetted Perimeter: 97.6428 ft

Hydraulic Radius: 0.5685 ft

Average Velocity: 8.5029 ft/s

Top Width: 97.5994 ft

Froude Number: 1.9869

Critical Depth: 1.3907 ft

Critical Velocity: 4.9160 ft/s

Critical Slope: 0.0023 ft/ft

Critical Top Width: 128.07 ft

Calculated Max Shear Stress: 0.6438 lb/ft^2

Calculated Avg Shear Stress: 0.3547 lb/ft^2

Channel Analysis: 59+60

Input Parameters

Channel Type: Trapezoidal

Side Slope 1 (Z1): 20.0000 ft/ft

Side Slope 2 (Z2): 12.9000 ft/ft

Channel Width: 10.0000 ft

Longitudinal Slope: 0.0100 ft/ft

Manning's n: 0.0120

Flow: 9.2000 cfs

Result Parameters

Depth: 0.1940 ft

Area of Flow: 2.5585 ft^2

Wetted Perimeter: 16.3937 ft

Hydraulic Radius: 0.1561 ft

Average Velocity: 3.5959 ft/s

Top Width: 16.3813 ft

Froude Number: 1.6035

Critical Depth: 0.2564 ft

Critical Velocity: 2.5231 ft/s

Critical Slope: 0.0036 ft/ft

Critical Top Width: 18.44 ft

Calculated Max Shear Stress: 0.1210 lb/ft^2

Calculated Avg Shear Stress: 0.0974 lb/ft^2

Channel Analysis: 138+10

Input Parameters

Channel Type: Trapezoidal

Side Slope 1 (Z1): 20.0000 ft/ft

Side Slope 2 (Z2): 12.9000 ft/ft

Channel Width: 10.0000 ft

Longitudinal Slope: 0.0100 ft/ft

Manning's n: 0.0120

Flow: 126.0000 cfs

Result Parameters

Depth: 0.7456 ft

Area of Flow: 16.5998 ft^2

Wetted Perimeter: 34.5767 ft

Hydraulic Radius: 0.4801 ft

Average Velocity: 7.5904 ft/s

Top Width: 34.5292 ft

Froude Number: 1.9292

Critical Depth: 1.0329 ft

Critical Velocity: 4.5192 ft/s

Critical Slope: 0.0025 ft/ft

Critical Top Width: 43.98 ft

Calculated Max Shear Stress: 0.4652 lb/ft^2

Calculated Avg Shear Stress: 0.2996 lb/ft^2

Riprap Analysis: LWC 27+35 Riprap Rev

Input Parameters

Riprap Type: Embankment Overtopping

Calculations will use either total or overbank discharges.

Total Discharge: 106 cfs

Embankment Slope: 4:1 H:V

Embankment Overtopping Length: 85 ft/s

Weir Flow Coefficient: 2.84

Riprap Sizing Equation Coefficient: 0.525 s^0.52/ft^0.04

Coefficient of Uniformity of the Riprap: 2.1

Coefficient of Uniformity = D60/D10

Porosity: 0.45

Angle of Repose: 42 degrees

Specific Gravity of Riprap: 2.65

Result Parameters

Overtopping Depth: 0.577713 ft

Depth determined from rectangular weir equation

Unit Discharge: 1.24706 cfs

Slope: 0.25 ft/ft

Slope Angle: 14.0362 degrees

Smallest Possible Median Rock Size: 3.4798 in

Interstitial Velocity: 0.892378 ft/s

Average Velocity: 0.40157 ft/s

Thickness required for all flow to pass thru Riprap: 3.10546 ft

Allowable Flow Depth over the Riprap: 0.19911 ft

Manning's Roughness Coefficient (n): 0.0306974

Unit Discharge over Riprap using Manning's Equation: 1.64327 cfs/ft

Required Interstitial Flow through the Riprap: 0 cfs/ft

Flow Provided by a riprap thickness of 2*d50: 0.435034 cfs/ft

Thickness required for Flow: 2*d50

Riprap Class

Riprap Class Name: CLASS I

Riprap Class Order: 1

The following values are an 'average' of the size fraction range for the selected riprap class.

d100: 12 in d85: 9 in d50: 6.5 in d15: 4.5 in

Name of Selected Channel: 27+35

Riprap Analysis: LWC 45+00 Riprap Rev

Input Parameters

Riprap Type: Embankment Overtopping

Calculations will use either total or overbank discharges.

Total Discharge: 472 cfs

Embankment Slope: 4:1 H:V

Embankment Overtopping Length: 98 ft/s

Weir Flow Coefficient: 2.84

Riprap Sizing Equation Coefficient: 0.525 s^0.52/ft^0.04

Coefficient of Uniformity of the Riprap: 2.1

Coefficient of Uniformity = D60/D10

Porosity: 0.45

Angle of Repose: 42 degrees

Specific Gravity of Riprap: 2.65

Result Parameters

Overtopping Depth: 1.42211 ft

Depth determined from rectangular weir equation

Unit Discharge: 4.81633 cfs

Slope: 0.25 ft/ft

Slope Angle: 14.0362 degrees

Smallest Possible Median Rock Size: 7.02595 in

Interstitial Velocity: 1.23751 ft/s

Average Velocity: 0.556877 ft/s

Thickness required for all flow to pass thru Riprap: 8.64881 ft

Allowable Flow Depth over the Riprap: 0.382904 ft

Manning's Roughness Coefficient (n): 0.0342321

Unit Discharge over Riprap using Manning's Equation: 4.38232 cfs/ft

Required Interstitial Flow through the Riprap: 0.434002 cfs/ft

Flow Provided by a riprap thickness of 2*d50: 1.16016 cfs/ft

Number of Iterations: 2

Riprap Class Order: 1

The following values are an 'average' of the size fraction range for the selected riprap class.

d100: 12 in d85: 9 in d50: 6.5 in

Name of Selected Channel: 45+00

Riprap Analysis: LWC 59+60 Riprap Rev

Input Parameters

Riprap Type: Embankment Overtopping

Calculations will use either total or overbank discharges.

Total Discharge: 9.2 cfs

Embankment Slope: 4:1 H:V

Embankment Overtopping Length: 16 ft/s

Weir Flow Coefficient: 2.84

Riprap Sizing Equation Coefficient: 0.525 s^0.52/ft^0.04

Coefficient of Uniformity of the Riprap: 2.1

Coefficient of Uniformity = D60/D10

Porosity: 0.45

Angle of Repose: 42 degrees

Specific Gravity of Riprap: 2.65

Result Parameters

Overtopping Depth: 0.344799 ft

Depth determined from rectangular weir equation

Unit Discharge: 0.575 cfs

Slope: 0.25 ft/ft

Slope Angle: 14.0362 degrees

Smallest Possible Median Rock Size: 2.32659 in

Interstitial Velocity: 0.892378 ft/s

Average Velocity: 0.40157 ft/s

Thickness required for all flow to pass thru Riprap: 1.43188 ft

Allowable Flow Depth over the Riprap: 0.19911 ft

Manning's Roughness Coefficient (n): 0.0306974

Unit Discharge over Riprap using Manning's Equation: 1.64327 cfs/ft

Required Interstitial Flow through the Riprap: 0 cfs/ft

Flow Provided by a riprap thickness of 2*d50: 0.435034 cfs/ft

Riprap Class Order: 1

The following values are an 'average' of the size fraction range for the selected riprap class.

d100: 12 in d85: 9 in d50: 6.5 in

Name of Selected Channel: 59+60

Riprap Analysis: LWC 138+10 Riprap Rev

Input Parameters

Riprap Type: Embankment Overtopping

Calculations will use either total or overbank discharges.

Total Discharge: 126 cfs

Embankment Slope: 4:1 H:V

Embankment Overtopping Length: 35 ft/s

Weir Flow Coefficient: 2.84

Riprap Sizing Equation Coefficient: 0.525 s^0.52/ft^0.04

Coefficient of Uniformity of the Riprap: 2.1

Coefficient of Uniformity = D60/D10

Porosity: 0.45

Angle of Repose: 42 degrees

Specific Gravity of Riprap: 2.65

Result Parameters

Overtopping Depth: 1.17127 ft

Depth determined from rectangular weir equation

Unit Discharge: 3.6 cfs

Slope: 0.25 ft/ft

Slope Angle: 14.0362 degrees

Smallest Possible Median Rock Size: 6.03907 in

Interstitial Velocity: 1.07883 ft/s

Average Velocity: 0.485474 ft/s

Thickness required for all flow to pass thru Riprap: 7.41543 ft

Allowable Flow Depth over the Riprap: 0.291007 ft

Manning's Roughness Coefficient (n): 0.0327016

Unit Discharge over Riprap using Manning's Equation: 2.90352 cfs/ft

Required Interstitial Flow through the Riprap: 0.696479 cfs/ft

Flow Provided by a riprap thickness of 2*d50: 0.768668 cfs/ft

Number of Iterations: 2

Riprap Class Order: 1

The following values are an 'average' of the size fraction range for the selected riprap class.

d100: 12 in d85: 9 in d50: 6.5 in

Name of Selected Channel: 138+10

HY-8 Culvert Analysis Report

Crossing Discharge Data

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

Minimum Flow: 0 cfs

Design Flow: 10 cfs

Maximum Flow: 17.7 cfs

Table 1 - Summary of Culvert Flows at Crossing: 24 Inch

Headwater Elevation

(ft) Total Discharge (cfs) Culvert 1 Discharge

(cfs) Roadway Discharge

(cfs) Iterations

100.00 0.00 0.00 0.00 1

100.67 1.77 1.77 0.00 1

100.97 3.54 3.54 0.00 1

101.21 5.31 5.31 0.00 1

101.42 7.08 7.08 0.00 1

101.61 8.85 8.85 0.00 1

101.74 10.00 10.00 0.00 1

102.02 12.39 12.39 0.00 1

102.27 14.16 14.16 0.00 1

102.56 15.93 15.93 0.00 1

102.85 17.70 17.70 0.00 1

106.00 29.08 29.08 0.00 Overtopping

Table 2 - Culvert Summary Table: Culvert 1

Total Discharg e (cfs) Culvert

Discharg e (cfs)

Headwat er

Elevatio n (ft)

Inlet Control Depth

(ft)

Outlet Control Depth

(ft) Flow Type

Normal Depth

(ft) Critical Depth

(ft) Outlet Depth

(ft) Tailwate r Depth

(ft) Outlet

Velocity (ft/s)

Tailwate r

Velocity (ft/s)

0.00 0.00 100.00 0.000 0.000 0-NF 0.000 0.000 0.000 0.000 0.000 0.000

1.77 1.77 100.67 0.670 0.0* 1-S2n 0.420 0.458 0.420 0.122 3.563 1.453

3.54 3.54 100.97 0.966 0.0* 1-S2n 0.597 0.653 0.597 0.186 4.350 1.908

5.31 5.31 101.21 1.208 0.0* 1-S2n 0.739 0.809 0.761 0.238 4.675 2.234

7.08 7.08 101.42 1.416 0.245 1-S2n 0.866 0.945 0.866 0.283 5.249 2.498

8.85 8.85 101.61 1.611 0.529 1-S2n 0.985 1.060 0.985 0.325 5.554 2.723

10.00 10.00 101.74 1.738 0.0* 1-S2n 1.061 1.126 1.061 0.350 5.721 2.854

12.39 12.39 102.02 2.025 1.182 5-S2n 1.217 1.263 1.217 0.400 6.002 3.097

14.16 14.16 102.27 2.266 1.552 5-S2n 1.337 1.352 1.337 0.435 6.161 3.259

15.93 15.93 102.56 2.540 2.565 7-M2 c 1.470 1.434 1.434 0.467 6.607 3.408

17.70 17.70 102.85 2.847 2.723 7-M2 c 2.000 1.514 1.514 0.499 6.937 3.546

* Full Flow Headwater elevation is below inlet invert.

Straight Culvert

Inlet Elevation (invert): 100.00 ft, Outlet Elevation (invert): 99.00 ft

Culvert Length: 50.01 ft, Culvert Slope: 0.0200

Site Data - Culvert 1

Site Data Option: Culvert Invert Data

Inlet Station: 0.00 ft

Inlet Elevation: 100.00 ft

Outlet Station: 50.00 ft

Outlet Elevation: 99.00 ft

Number of Barrels: 1

Culvert Data Summary - Culvert 1

Barrel Shape: Circular

Barrel Diameter: 2.00 ft

Barrel Material: Corrugated Steel

Embedment: 0.00 in

Barrel Manning's n: 0.0240

Culvert Type: Straight

Inlet Configuration: Mitered to Conform to Slope

Inlet Depression: None

Table 3 - Downstream Channel Rating Curve (Crossing: 24 Inch)

Tailwater Channel Data - 24 Inch

Tailwater Channel Option: Rectangular Channel

Bottom Width: 10.00 ft

Channel Slope: 0.0200

Channel Manning's n: 0.0350

Channel Invert Elevation: 99.00 ft

Roadway Data for Crossing: 24 Inch

Roadway Profile Shape: Constant Roadway Elevation

Crest Length: 100.00 ft

Crest Elevation: 106.00 ft

Roadway Surface: Paved

Roadway Top Width: 24.00 ft

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

0.00 99.00 0.00 0.00 0.00 0.00

1.77 99.12 0.12 1.45 0.15 0.73

3.54 99.19 0.19 1.91 0.23 0.78

5.31 99.24 0.24 2.23 0.30 0.81

7.08 99.28 0.28 2.50 0.35 0.83

8.85 99.33 0.33 2.72 0.41 0.84

10.00 99.35 0.35 2.85 0.44 0.85

12.39 99.40 0.40 3.10 0.50 0.86

14.16 99.43 0.43 3.26 0.54 0.87

15.93 99.47 0.47 3.41 0.58 0.88

17.70 99.50 0.50 3.55 0.62 0.88

Crossing Discharge Data

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

Minimum Flow: 0 cfs

Design Flow: 10 cfs

Maximum Flow: 31.1 cfs

Table 4 - Summary of Culvert Flows at Crossing: 30 Inch

Headwater Elevation

(ft) Total Discharge (cfs) Culvert 1 Discharge

(cfs) Roadway Discharge

(cfs) Iterations

100.00 0.00 0.00 0.00 1

100.84 3.11 3.11 0.00 1

101.21 6.22 6.22 0.00 1

101.52 9.33 9.33 0.00 1

101.57 10.00 10.00 0.00 1

102.02 15.55 15.55 0.00 1

102.27 18.66 18.66 0.00 1

102.54 21.77 21.77 0.00 1

102.85 24.88 24.88 0.00 1

103.19 27.99 27.99 0.00 1

103.58 31.10 31.10 0.00 1

106.00 46.04 46.04 0.00 Overtopping

Table 5 - Culvert Summary Table: Culvert 1

Total Discharg e (cfs) Culvert

Discharg e (cfs)

Headwat er

Elevatio n (ft)

Inlet Control Depth

(ft)

Outlet Control Depth

(ft) Flow Type

Normal Depth

(ft) Critical Depth

(ft) Outlet Depth

(ft) Tailwate r Depth

(ft) Outlet

Velocity (ft/s)

Tailwate r

Velocity (ft/s)

0.00 0.00 100.00 0.000 0.000 0-NF 0.000 0.000 0.000 0.000 0.000 0.000

3.11 3.11 100.84 0.838 0.0* 1-S2n 0.517 0.575 0.517 0.172 4.090 1.812

6.22 6.22 101.21 1.210 0.0* 1-S2n 0.734 0.823 0.734 0.262 5.001 2.375

9.33 9.33 101.52 1.515 0.198 1-S2n 0.909 1.015 0.909 0.336 5.590 2.778

10.00 10.00 101.57 1.574 0.264 1-S2n 0.943 1.054 0.943 0.350 5.701 2.854

15.55 15.55 102.02 2.021 0.837 1-S2n 1.209 1.328 1.209 0.461 6.395 3.376

18.66 18.66 102.27 2.270 1.192 1-S2n 1.350 1.460 1.386 0.516 6.469 3.617

21.77 21.77 102.54 2.543 1.580 5-S2n 1.490 1.583 1.533 0.568 6.693 3.833

24.88 24.88 102.85 2.848 1.997 5-S2n 1.634 1.695 1.634 0.618 7.107 4.029

27.99 27.99 103.19 3.194 2.449 5-S2n 1.788 1.802 1.788 0.665 7.247 4.209

31.10 31.10 103.58 3.583 3.454 7-M2 c 1.971 1.898 1.898 0.711 7.779 4.376

* Full Flow Headwater elevation is below inlet invert.

Straight Culvert

Inlet Elevation (invert): 100.00 ft, Outlet Elevation (invert): 99.00 ft

Culvert Length: 50.01 ft, Culvert Slope: 0.0200

Site Data - Culvert 1

Site Data Option: Culvert Invert Data

Inlet Station: 0.00 ft

Inlet Elevation: 100.00 ft

Outlet Station: 50.00 ft

Outlet Elevation: 99.00 ft

Number of Barrels: 1

Culvert Data Summary - Culvert 1

Barrel Shape: Circular

Barrel Diameter: 2.50 ft

Barrel Material: Corrugated Steel

Embedment: 0.00 in

Barrel Manning's n: 0.0240

Culvert Type: Straight

Inlet Configuration: Mitered to Conform to Slope

Inlet Depression: None

Table 6 - Downstream Channel Rating Curve (Crossing: 30 Inch)

Tailwater Channel Data - 30 Inch

Tailwater Channel Option: Rectangular Channel

Bottom Width: 10.00 ft

Channel Slope: 0.0200

Channel Manning's n: 0.0350

Channel Invert Elevation: 99.00 ft

Roadway Data for Crossing: 30 Inch

Roadway Profile Shape: Constant Roadway Elevation

Crest Length: 100.00 ft

Crest Elevation: 106.00 ft

Roadway Surface: Paved

Roadway Top Width: 24.00 ft

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

0.00 99.00 0.00 0.00 0.00 0.00

3.11 99.17 0.17 1.81 0.21 0.77

6.22 99.26 0.26 2.38 0.33 0.82

9.33 99.34 0.34 2.78 0.42 0.84

10.00 99.35 0.35 2.85 0.44 0.85

15.55 99.46 0.46 3.38 0.57 0.88

18.66 99.52 0.52 3.62 0.64 0.89

21.77 99.57 0.57 3.83 0.71 0.90

24.88 99.62 0.62 4.03 0.77 0.90

27.99 99.66 0.66 4.21 0.83 0.91

31.10 99.71 0.71 4.38 0.89 0.91