Hydraulics Report.pdf

PDF 4 MB Posted Jan 28, 2021

Attached to: CA ER 511(1), Trinity County Ruth-Zenia Road Federal contract opportunity
Solicitation number: 6982AF20B000032
Issued by: Department of Transportation Federal Highway Administration

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Written by GovTribe AI · Dec 28, 2023

This document contains a hydrology report and information on a related federal contract opportunity. The hydrology report provides details on existing conditions, proposed design, hydrologic analysis, and hydraulic design criteria for the Van Duzen Road Repair Project in Trinity County, California. It involves reconstruction and realignment of 300 feet of damaged roadway along the Van Duzen River to restore it to a two-lane road. Hydrologic analysis was conducted using the Rational Method on drainage basins under 1 acre in size. The minimum culvert size is 18 inches and ditches must pass a 10-year storm. The related federal contract opportunity is a solicitation for the CA ER 511(1) Trinity County Ruth-Zenia Road Storm Damage Repair Project. It involves repairs to storm damage at 12 sites across 5 routes, including slope scaling, excavation, embankments, drainage repairs, and other work. Quantities include 15,500 cubic yards of excavation and 1,100 tons of asphalt. The anticipated award date is March 2021, with construction from Spring to Fall 2021. The estimated cost is between $4-6 million.

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Other files attached to CA ER 511(1), Trinity County Ruth-Zenia Road, newest first.
File	Type	Posted
Tabulation of Bids-CA ER 511(1) Trinity County Ruth-Zenia Road.pdf	PDF	Mar 11, 2021
Bid Opening Summary - CA ER 511(1) Trinity County Ruth-Zenia Road.pdf	PDF	Mar 2, 2021
Interested Vendors List 2 26 2021.pdf	PDF	Feb 26, 2021
Quick Start Guide_Opportunities 4 Contractors including Interested Vendor List info.pdf	PDF	Feb 26, 2021
QnA 2 25 2021.pdf	PDF	Feb 25, 2021
QnA 2 24 2021.pdf	PDF	Feb 24, 2021
Amendment A001.pdf	PDF	Feb 24, 2021
QnA 2 23 2021.pdf	PDF	Feb 23, 2021
Interested Vendors List 2 22 2021.pdf	PDF	Feb 22, 2021
QnA 2 10 2021.pdf	PDF	Feb 10, 2021
Interested Vendors List 02 03 2021.pdf	PDF	Feb 3, 2021
QnA 2 2 2021.pdf	PDF	Feb 2, 2021
fp14.pdf	PDF	Jan 28, 2021
Plans.pdf	PDF	Jan 28, 2021
6982AF20B000032 IFB.pdf	PDF	Jan 28, 2021
Geotech Report.pdf	PDF	Jan 28, 2021

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HYDRAULICS REPORT FOR THE VAN DUZEN ROAD REPAIR PROJECT

Hydraulics Report for the Van Duzen Road Repair Project PREPARED FOR: Dustin Robbins, PE/CFLHD

COPY TO: Ed Henderson, PE/Jacobs

PREPARED BY: Nicole Lapp/Jacobs

REVIEWED BY: Travis Howard, PE/Jacobs

DATE: August 27, 2020

PROJECT NUMBER: WXXY0600

Introduction The purpose of this report is to document the existing and proposed hydrologic and hydraulic conditions associated with the Van Duzen Road Repair Project and to document the drainage design criteria used for final design. No Hydrologic or Hydraulic Analysis was performed at any of the other 11 sites.

Project Description

The Van Duzen Road Project consists of improvements to a 300‐foot corridor of roadway near the Van Duzen River. The road is situated in the western reaches of Trinity County in the Six Rivers National Forest at an elevation that ranges from approximately 2,565 feet to 2,571 feet above mean sea level.

The road begins at the intersection with Ruth‐Zenia Road and terminates at Highway 36. The road is owned by the U.S. Forest Service and serves as the primary access point for the Southern Trinity High School, in addition to providing access to multiple residential properties. The roadway has a 55‐mph posted speed.

The project is considered a 4R project and will involve a complete reconstruction and realignment of the damaged roadway. The term 4R stands for Resurfacing, Restoration, Rehabilitation and Reconstruction.

See Appendix A for a location map that provides a visual representation of the project components described above. A vicinity map is also included in Appendix A.

Existing Conditions

The existing roadway for Van Duzen Road consists of a paved surface. The roadway operates as a two‐ lane, two‐way road for the undamaged portions. The damaged roadway operates as a one‐lane, two‐ way road with K‐rail barriers on the river side where the road washed out. The 300 feet of damaged roadway is on a level grade that averages approximately 0.5‐1% as the roadway runs along the Van Duzen River. The surrounding terrain is mountainous with fair vegetative cover ranging from scattered grasses and brush to large coniferous forests.

The existing drainage facilities include informal roadside ditches coupled with a culvert under a driveway. The existing culvert is an 18‐inch corrugated metal pipe (CMP) culvert located at STA 14+85.00 running parallel to Van Duzen Road. There are no formal gutters, ditches or catch basins. Flow along the project segment is dispersed in a large pull out east of the site. Onsite runoff either runs directly off the road to Van Duzen River or is collected in a roadside ditch and conveyed to the east.

Once on the downstream side of the road, the runoff eventually makes its way to the Van Duzen River.

Roadway cross slope varies along the entire corridor with certain portions super‐elevated and certain portions in a normal crown.

thoward2 Typewritten Text 8-27-20

Proposed Conditions

The proposed project involves a complete realignment and reconstruction of the roadway. The road will be restored from a one‐lane road to a two‐lane road (11‐foot lanes with 2‐foot shoulders). A 4‐foot wide earthen ditch on both sides of the road is being proposed to collect onsite and offsite drainage. The existing culvert will be removed and replaced. The posted speed limit will remain at 55 mph with a design speed of 55 mph.

Hydrology

Design Criteria

The Federal Lands Highway Project Development and Design Manual (PDDM) published by the U.S.

Department of Transportation Federal Highway Administration is the primary guideline for Hydrologic criteria on the project. The edition dated March 2018 was used. A Hydrologic analysis was performed to determine flows entering the proposed drainage facilities for the project. Hydrologic calculations were based on the guidelines presented in the document titled Highway Design Series No. 2, Second Edition, Highway Hydrology (HDS‐2), published by the U.S. Department of Transportation Federal Highway Administration. The edition dated October 2002 was used. Peak flows were calculated using the Rational Method (Equation 5.28 from HDS‐2). See below for Equation 5.28. Use of the Rational Method is dependent on the maximum size of watershed. Per Section 5.3.1 of HDS‐2 the maximum drainage area should be smaller than 200 acres for the Rational Method to work properly. All watersheds within the project are below 1 acre in size. An evaluation of the topography revealed the largest drainage basin to be approximately 0.7 acres in size.

Rational Formula, Equation 5.28

Below is a summary of the components of the Rational Method as they relate to this project.

Runoff Coefficient (C): Runoff coefficients were based on Table 5.7 of HDS‐2. A value of 0.90 was used for the onsite runoff coefficient, which is typical for paved surfaces such as the proposed and existing roadway. Table 5.7 from HDS‐2 is included in Appendix B.

Rainfall Intensity (i): Values from NOAA Atlas 14 were used for rainfall intensity. A listing of the NOAA Atlas 14 rainfall data specific to this project’s location is included in Appendix B. Rainfall intensity values were selected based on the time of concentration calculated. Times of concentration for each basin were calculated using the FHWA Hydraulic Toolbox software, Version 4.2.

Drainage Area (A): The watershed boundaries were determined from the following sources:

– The projects topographic survey (1‐foot contour interval), limited to within 63 feet+/‐ of roadway CL

The ditch basin boundaries were developed using both the 1‐foot contours from the topographic survey and the proposed site layout. Due to limited range of the topographic survey the analysis of the available contours led to the conclusion that water off‐site will continue to drain off‐site. The basin maps are included in Appendix B.

Time of Concentration: The time of concentration was calculated in a manner consistent with Section 2.6, Travel Time, of HDS‐2. The total time of concentration used for each basin was a summation of the Sheet Flow travel time (derived from HDS‐2, Equation 2.6) and Channel Flow (derived from HDS‐2, Equation 2.8). Shallow Concentrated Flow travel time was not used due to the small size of the basins; length of sheet flow was less than the maximum distance. Key values to be used in time of concentration calculations are listed below.

– Maximum Sheet Flow Distance: 300 feet (HDS‐2, Section 2.6.2.1)

– Manning’s Roughness Coefficient (n) for Sheet Flow: 0.011 (HDS‐2, Table 2.1, Smooth asphalt). Table 2.1 included in Appendix B.

– Manning’s Roughness Coefficient (n) for Channels and Pipes: To be based on Table 3‐4 of

Hydraulic Engineering Circular No. 22 (HEC‐22), Third Edition, Urban Drainage Design Manual, published by the U.S. Department of Transportation Federal Highway Administration. Table 3.4 included in Appendix B.

– Minimum time of concentration: 5 minutes (HEC‐22, Section 7.2.2)

Calculations

Project‐wide hydrology and hydraulics were calculated using the FHWA Hydraulic Toolbox software, Version 4.2. A summary of the hydrologic calculations for the ditch basins can be found in Table 1. The Hydraulic Toolbox reports for each basin can be found in Appendix E.

C A

(acres) tc (min) i (in/h) Q (ft3/s)

Ditch location 10yr 10 yr 10 yr

Right‐preculvert 0.9 0.28 15.12 1.90 0.50

Right‐postculvert 0.9 0.26 16.67 1.80 0.40

Right‐culvert combined 0.9 0.54 29.28 1.34 0.70

Right‐end alignment 0.9 0.25 24.45 1.47 0.30

Left 0.9 0.71 35.22 1.21 0.80

Table 1: Hydrology Summary; 10‐year design storm

Hydraulics

Design Criteria

The Federal Lands Highway Project Development and Design Manual (PDDM) published by the U.S.

Department of Transportation Federal Highway Administration is the primary guideline for Hydraulic criteria on the project. The edition dated March 2018 was used.

Drainage facilities in the project were analyzed in a manner consistent with the guidelines in the PDDM.

For the purposes of hydraulic analysis, the roadway is considered a High‐Standard Road consistent with the guidelines established in Section 7.1.6.1 of the PDDM. High standard roads have a design speed greater than 45 mph or an ADT greater than 1,500 or are designated a critical access road. The Van

Duzen Road has a design speed of 55 mph, an ADT of 185, and is not considered a critical access road, therefore it is classified as a High‐Standard Road.

Exhibit 7.1A in the PDDM provides a quick reference guide to the key pieces of hydraulic criteria associated with commonly encountered drainage facilities. Exhibit 7.1A is included in Appendix C with project specific criteria highlighted. Key hydraulic criteria that were employed on this project are summarized below.

Parallel Culverts

– Minimum Size: 18‐inches

Ditches Design Storm: 10‐year

Inlet to Culvert. CFL standard flared culvert ends were selected as the preferred entrance condition.

Ditches. Ditches were analyzed using the Hydraulic Toolbox. The initial analysis of ditches was performed using only the runoff from the associated basins. A secondary analysis was performed on the ditches preceding and following the culvert using the combined basin. In order to provide capacity and a natural feel, trapezoidal ditches with 4‐foot channel width and 4:1 side slopes was selected. See Table 2 for a summary of the channel calculations. The Hydraulic Toolbox reports can be found in Appendix E.

Culverts

The minimum standard parallel culvert diameter is 18 inches per the PDDM. Due to limitations of cover between the crown of the culvert pipe and the driveway surface, a 12‐inch culvert diameter was analyzed. The culvert was analyzed using the culvert Hydraulic Analysis Program HY‐8 version 7.5 published by the Federal Highway Administration. According to the HDS‐5, as noted in the FHWA HY‐8 User Manual, “flared end sections made of either metal or concrete, are the section commonly available from manufacturers. From limited hydraulic tests they are equivalent in operation to a headwall in both inlet and outlet control.” Based on this equivalency, a headwall was used as the inlet condition for the purposes of the HY‐8 cross culvert analysis. An actual headwall will not be utilized.

The maximum headwater elevation possible to avoid overtopping was selected as the elevation of the access road at the culvert, being a lower elevation than that of the roadway.

A summary of the culvert analysis can be found in Table 3. The proposed 12‐inch culvert adequately passes the design flow.

The existing culvert will be removed and replaced with a standard sized culvert (12‐inch) as there is not adequate cover between the crown of the culvert pipe and the driveway surface to accommodate the standard 18‐inch culvert diameter.

The HY‐8 report for the culvert can be found in Appendix F.

Riprap. The new culvert will have placed riprap installed at the outlet. As the culvert has a gentle slope (<10%) standard placed riprap per CFL Standard Drawing C251‐50 was utilized.

Channel W. (ft)

Lt Side Slope (ft)

Rt Side Slope (ft)

Min.

Channel Depth (ft)

Manning's n

Longitudinal Slope

Flow (cfs)

Depth (ft) Max. water depth (ft) [WSEL = bottom of agg base layer]

Compliant?

Rt‐preculvert 4 25% 25% 1.5 0.15 0.50% 0.50 0.33 1.06 Yes

Rt‐postculvert 4 25% 25% 1.5 0.15 0.50% 0.40 0.29 1.95 Yes

Rt‐culvert comb. 4 25% 25% 1.5 0.15 0.50% 0.70 0.40 1.95 Yes

Rt‐end align. 4 25% 25% 1.5 0.15 0.50% 0.30 0.25 0.75 Yes

Lt 4 25% 25% 1.5 0.15 0.50% 0.80 0.43 0.74 Yes

Table 2: Ditch Hydraulics Summary; 10‐year design storm

Type Dia.

(in)

Manning's n

Culv.

Slope

L (ft) Tot.

Dischg (cfs)

Culv.

Dischg (cfs)

Road Dischg (cfs)

Inlet Inv.

Elev.

Out. Inv.

Elev.

Head water Elev.

Head water D (ft)

Max.

Head water Elev.

Outlet V.

(ft/s)

Overtop

14+85 Cor.

Steel, Circ., Strt

12 0.024 0.49% 22.51 0.5 0.5 0.0 2566.42 2566.31 2566.89 0.47 2568.20 0.29 No

Table 3: Culvert Discharge Summary; 10‐year design storm

Culvert Corrosion Exhibit 7.3‐B in the PDDM was used with the Ph and Resistivity in pages 86‐88 of the Geotech report estimate the service life for the culvert. Using the thickness factor for a culvert thickness of 0.079 inches the estimated service life exceeds 50 years. Exhibit 7.3‐B is included in Appendix G.

Floodplain The floodplain relative to this project was reviewed. Published FEMA maps (National Flood Hazard Layer FIRMette, dated January 20, 2010) show this project to be entirely in Zone D, which is classified as Area of Undetermined Flood Hazard, and lists panel 06105C1325E as “not printing”. No impacts to the floodplain are anticipated as part of this project. The relevant FEMA Flood Map is attached in Appendix D.

Environmental Impacts The California Construction General Permit requires best management practices (BMPs) for mitigating hydromodification associated with increases in the impervious area. This segment will slightly increase runoff due to the increase in impervious area associated with the road realignment. There will be approximately 0.67 acres of impervious area after construction, compared to 0.59 acres of pre‐storm damage impervious area prior to construction. The increased ditch capacity will accommodate the marginal increase in flow due to the increased impervious area. The hydraulics aspects of this project are not anticipated to have significant environmental impacts.

Conclusions This document provides a summary of the existing and proposed hydrologic and hydraulic conditions associated with the Van Duzen Road Emergency Repair Project. All proposed drainage facilities adequately comply with the established project criteria. There are no adverse effects to surrounding properties anticipated as a part of this project.

Appendix A – Location and Vicinity Maps

Project Start

Project End

Location Map

Van Duzen Road Emergency Repair Project

Vicinity Map

Appendix B – Hydrology

Right Ditch Pre-culvert

Right Ditch Post-culvert

Right Ditch End of Alignment Left Ditch

Van Duzen Road Ditch Basins March 10, 2020

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Table 3-4. Typical Range of Manning's Coefficient (n) for Channels and Pipes.

Conduit Material Manning's n*

Closed Conduits

Concrete pipe 0.010 - 0.015

CMP 0.011 - 0.037

Plastic pipe (smooth) 0.009 - 0.015 Plastic pipe (corrugated) 0.018 - 0.025

Pavement/gutter sections 0.012 - 0.016

Small Open Channels

Concrete 0.011 - 0.015 Rubble or riprap 0.020 - 0.035 Vegetation 0.020 - 0.150

Bare Soil 0.016 - 0.025 Rock Cut 0.025 - 0.045

Natural channels (minor streams, top width at flood stage <30 m (100 ft))

Fairly regular section 0.025 - 0.050 Irregular section with pools 0.040 - 0.150

*Lower values are usually for well-constructed and maintained (smoother) pipes and channels

0.150

(2.6)

Appendix C – Hydraulics

(Continued)

Appendix D – Flood Plain Maps

USGS The National Map: Orthoimagery. Data refreshed April, 2019.

National Flood Hazard Layer FIRMette

0 500 1,000 1,500 2,000250 Feet

3°

"W 40°25'4.29"N

123°30'49.60"W

40°24'36.90"N

SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT

SPECIAL FLOOD

HAZARD AREAS

Without Base Flood Elevation (BFE) Zone A, V, A99

With BFE or Depth Zone AE, AO, AH, VE, AR

Regulatory Floodway

0.2% Annual Chance Flood Hazard, Areas of 1% annual chance flood with average depth less than one foot or with drainage areas of less than one square mile Zone X

Future Conditions 1% Annual Chance Flood Hazard Zone X

Area with Reduced Flood Risk due to Levee. See Notes. Zone X

Area with Flood Risk due to Levee Zone D

NO SCREEN Area of Minimal Flood Hazard Zone X

Area of Undetermined Flood Hazard Zone D

Channel, Culvert, or Storm Sewer

Levee, Dike, or Floodwall

Cross Sections with 1% Annual Chance

17.5 Water Surface Elevation

Coastal Transect

Coastal Transect Baseline Profile Baseline Hydrographic Feature

Base Flood Elevation Line (BFE)

Effective LOMRs

Limit of Study Jurisdiction Boundary

Digital Data Available

No Digital Data Available

Unmapped

This map complies with FEMA's standards for the use of digital flood maps if it is not void as described below.

The basemap shown complies with FEMA's basemap accuracy standards

The flood hazard information is derived directly from the authoritative NFHL web services provided by FEMA. This map was exported on 3/9/2020 at 2:06:38 AM and does not reflect changes or amendments subsequent to this date and time. The NFHL and effective information may change or become superseded by new data over time.

This map image is void if the one or more of the following map elements do not appear: basemap imagery, flood zone labels, legend, scale bar, map creation date, community identifiers, FIRM panel number, and FIRM effective date. Map images for unmapped and unmodernized areas cannot be used for regulatory purposes.

Legend

OTHER AREAS OF

FLOOD HAZARD

OTHER AREAS

GENERAL

STRUCTURES

OTHER

FEATURES

MAP PANELS

1:6,000

B 20.2

The pin displayed on the map is an approximate point selected by the user and does not represent an authoritative property location.

Appendix E – Hydraulic Toolbox Reports

Hydraulic Analysis Report Project Data

Project Title: VanDuzen Designer:

Project Date: Monday, March 09, 2020 Project Units: U.S. Customary Units Notes:

Rational Analysis: Ditch-rt-culvert_comb Notes:

Rational Method Input Parameters Runoff Coefficient: 0.90 Basin Area: 0.5400 acres Rainfall Intensity: 1.34 in/hr Time of Concentration: 29.28 minutes Recurrence Year: 10 year

Rational Method Results Flowrate: 0.7 cfs

IDF Input Parameters

User Supplied Data 2 year Recurrence, 5 min duration: 2.3 in/hr 2 year Recurrence, 10 min duration: 1.65 in/hr 2 year Recurrence, 15 min duration: 1.33 in/hr 2 year Recurrence, 30 min duration: 0.924 in/hr 2 year Recurrence, 60 min duration: 0.638 in/hr 5 year Recurrence, 5 min duration: 2.84 in/hr 5 year Recurrence, 10 min duration: 2.04 in/hr 5 year Recurrence, 15 min duration: 1.64 in/hr 5 year Recurrence, 30 min duration: 1.14 in/hr 5 year Recurrence, 60 min duration: 0.788 in/hr 10 year Recurrence, 5 min duration: 3.3 in/hr 10 year Recurrence, 10 min duration: 2.36 in/hr 10 year Recurrence, 15 min duration: 1.9 in/hr 10 year Recurrence, 30 min duration: 1.32 in/hr 10 year Recurrence, 60 min duration: 0.911 in/hr 25 year Recurrence, 5 min duration: 3.91 in/hr 25 year Recurrence, 10 min duration: 2.8 in/hr 25 year Recurrence, 15 min duration: 2.26 in/hr 25 year Recurrence, 30 min duration: 1.57 in/hr 25 year Recurrence, 60 min duration: 1.08 in/hr 50 year Recurrence, 5 min duration: 4.39 in/hr 50 year Recurrence, 10 min duration: 3.14 in/hr 50 year Recurrence, 15 min duration: 2.54 in/hr 50 year Recurrence, 30 min duration: 1.76 in/hr 50 year Recurrence, 60 min duration: 1.21 in/hr 100 year Recurrence, 5 min duration: 4.88 in/hr 100 year Recurrence, 10 min duration: 3.5 in/hr 100 year Recurrence, 15 min duration: 2.82 in/hr 100 year Recurrence, 30 min duration: 1.96 in/hr 100 year Recurrence, 60 min duration: 1.35 in/hr

IDF Results 10 year IDF equation: i = 8.5416 / (Tc + 0.696393)^0.545111 Intensity: 1.3382 in/hr

Time of Concentration Input Parameters Computed Time of Concentration Time of Concentration: 29.28 min

Sheet Flow Input Parameters Top Elevation: 2571.43 ft Bottom Elevation: 2567.67 ft Length: 37.98 ft

Recommended length not to exceed 100'. Maximum length is 300' Manning's n: 0.0110

See HDS-2 Table 2.1 2 yr, 24 hr precip: 4.5840 in

Sheet Flow Results Slope: 0.0990 ft/ft Time of Concentration: 0.25 min

Channel Flow Input Parameters Define as: Channel Calculation Channel Name: Channel Analysis Top Elevation: 2567.66 ft Bottom Elevation: 2564.98 ft Length: 541.00 ft Manning's n: 0.1500

Channel Flow Results Slope: 0.0050 ft/ft Velocity: 0.3105 ft/s

Determined by Channel or Curb & Gutter Calculator Time of Concentration: 29.04 min

Total Time of Concentration Time of Concentration: 29.28 min Final Iterated Solution

Report for channel used in Time of Concentration calculations

Channel Analysis: Channel Analysis Notes:

Input Parameters Channel Type: Trapezoidal Side Slope 1 (Z1): 4.0000 ft/ft Side Slope 2 (Z2): 4.0000 ft/ft Channel Width: 4.0000 ft Longitudinal Slope: 0.0050 ft/ft Manning's n: 0.1500 Flow: 0.6558 cfs

Result Parameters Depth: 0.3820 ft Area of Flow: 2.1118 ft^2

Wetted Perimeter: 7.1502 ft Hydraulic Radius: 0.2954 ft Average Velocity: 0.3105 ft/s Top Width: 7.0561 ft Froude Number: 0.1000 Critical Depth: 0.0913 ft Critical Velocity: 1.6462 ft/s Critical Slope: 0.7528 ft/ft Critical Top Width: 4.73 ft Calculated Max Shear Stress: 0.1192 lb/ft^2 Calculated Avg Shear Stress: 0.0921 lb/ft^2

Project Title: VanDuzen Designer:

Project Date: Monday, March 09, 2020 Project Units: U.S. Customary Units Notes:

Channel Analysis: Channel Analysis Notes:

Result Parameters Depth: 0.4532 ft Area of Flow: 2.6344 ft^2 Wetted Perimeter: 7.7372 ft Hydraulic Radius: 0.3405 ft Average Velocity: 0.3416 ft/s Top Width: 7.6256 ft Froude Number: 0.1024 Critical Depth: 0.1119 ft Critical Velocity: 1.8086 ft/s Critical Slope: 0.7077 ft/ft Critical Top Width: 4.90 ft Calculated Max Shear Stress: 0.1414 lb/ft^2 Calculated Avg Shear Stress: 0.1062 lb/ft^2

Project Title: VanDuzen Designer:

Project Date: Monday, March 09, 2020 Project Units: U.S. Customary Units Notes:

Rational Analysis: Ditch-lt Notes:

Rational Method Input Parameters Runoff Coefficient: 0.90 Basin Area: 0.7100 acres Rainfall Intensity: 1.21 in/hr Time of Concentration: 35.22 minutes Recurrence Year: 10 year

Rational Method Results Flowrate: 0.8 cfs

2 year Recurrence, 10 min duration: 1.65 in/hr 2 year Recurrence, 15 min duration: 1.33 in/hr 2 year Recurrence, 30 min duration: 0.924 in/hr 2 year Recurrence, 60 min duration: 0.638 in/hr 5 year Recurrence, 5 min duration: 2.84 in/hr 5 year Recurrence, 10 min duration: 2.04 in/hr 5 year Recurrence, 15 min duration: 1.64 in/hr 5 year Recurrence, 30 min duration: 1.14 in/hr 5 year Recurrence, 60 min duration: 0.788 in/hr 10 year Recurrence, 5 min duration: 3.3 in/hr 10 year Recurrence, 10 min duration: 2.36 in/hr 10 year Recurrence, 15 min duration: 1.9 in/hr 10 year Recurrence, 30 min duration: 1.32 in/hr 10 year Recurrence, 60 min duration: 0.911 in/hr 25 year Recurrence, 5 min duration: 3.91 in/hr 25 year Recurrence, 10 min duration: 2.8 in/hr 25 year Recurrence, 15 min duration: 2.26 in/hr 25 year Recurrence, 30 min duration: 1.57 in/hr 25 year Recurrence, 60 min duration: 1.08 in/hr 50 year Recurrence, 5 min duration: 4.39 in/hr 50 year Recurrence, 10 min duration: 3.14 in/hr 50 year Recurrence, 15 min duration: 2.54 in/hr 50 year Recurrence, 30 min duration: 1.76 in/hr 50 year Recurrence, 60 min duration: 1.21 in/hr 100 year Recurrence, 5 min duration: 4.88 in/hr 100 year Recurrence, 10 min duration: 3.5 in/hr 100 year Recurrence, 15 min duration: 2.82 in/hr 100 year Recurrence, 30 min duration: 1.96 in/hr 100 year Recurrence, 60 min duration: 1.35 in/hr

IDF Results 10 year IDF equation: i = 8.5416 / (Tc + 0.696393)^0.545111 Intensity: 1.2127 in/hr

Time of Concentration Input Parameters Computed Time of Concentration Time of Concentration: 35.22 min

Sheet Flow Input Parameters Top Elevation: 2568.26 ft Bottom Elevation: 2567.10 ft Length: 35.34 ft

Manning's n: 0.1500

See HDS-2 Table 2.1 2 yr, 24 hr precip: 4.5840 in

Sheet Flow Results Slope: 0.0328 ft/ft Time of Concentration: 2.92 min

Channel Flow Input Parameters Define as: Channel Calculation Channel Name: Channel Analysis Top Elevation: 2567.00 ft Bottom Elevation: 2563.64 ft Length: 635.15 ft Manning's n: 0.1500

Channel Flow Results Slope: 0.0053 ft/ft Velocity: 0.3278 ft/s

Determined by Channel or Curb & Gutter Calculator Time of Concentration: 32.29 min

Total Time of Concentration Time of Concentration: 35.22 min Final Iterated Solution

Report for channel used in Time of Concentration calculations

Channel Analysis: Channel Analysis Notes:

Result Parameters Depth: 0.4197 ft Area of Flow: 2.3837 ft^2

Wetted Perimeter: 7.4613 ft Hydraulic Radius: 0.3195 ft Average Velocity: 0.3278 ft/s Top Width: 7.3579 ft Froude Number: 0.1015 Critical Depth: 0.1022 ft Critical Velocity: 1.7346 ft/s Critical Slope: 0.7274 ft/ft Critical Top Width: 4.82 ft Calculated Max Shear Stress: 0.1310 lb/ft^2 Calculated Avg Shear Stress: 0.0997 lb/ft^2

Project Title: VanDuzen Designer:

Project Date: Monday, March 09, 2020 Project Units: U.S. Customary Units Notes:

Channel Analysis: Channel Analysis-lt Notes:

Result Parameters Depth: 0.4252 ft Area of Flow: 2.4241 ft^2 Wetted Perimeter: 7.5064 ft Hydraulic Radius: 0.3229 ft Average Velocity: 0.3300 ft/s Top Width: 7.4017 ft Froude Number: 0.1016 Critical Depth: 0.1037 ft Critical Velocity: 1.7468 ft/s Critical Slope: 0.7241 ft/ft Critical Top Width: 4.83 ft Calculated Max Shear Stress: 0.1327 lb/ft^2 Calculated Avg Shear Stress: 0.1008 lb/ft^2

Project Title: VanDuzen Designer:

Project Date: Monday, March 09, 2020 Project Units: U.S. Customary Units Notes:

Channel Analysis: Channel Analysis-rt.comb Notes:

Result Parameters Depth: 0.3960 ft Area of Flow: 2.2114 ft^2 Wetted Perimeter: 7.2656 ft Hydraulic Radius: 0.3044 ft Average Velocity: 0.3165 ft/s Top Width: 7.1681 ft Froude Number: 0.1004 Critical Depth: 0.0952 ft Critical Velocity: 1.6787 ft/s Critical Slope: 0.7432 ft/ft Critical Top Width: 4.76 ft Calculated Max Shear Stress: 0.1236 lb/ft^2 Calculated Avg Shear Stress: 0.0950 lb/ft^2

Project Title: VanDuzen Designer:

Project Date: Monday, March 09, 2020 Project Units: U.S. Customary Units Notes:

Rational Analysis: Ditch-rt-end Notes:

Rational Method Input Parameters Runoff Coefficient: 0.90 Basin Area: 0.2500 acres Rainfall Intensity: 1.47 in/hr Time of Concentration: 24.45 minutes Recurrence Year: 10 year

Rational Method Results Flowrate: 0.3 cfs

IDF Results 10 year IDF equation: i = 8.5416 / (Tc + 0.696393)^0.545111 Intensity: 1.4728 in/hr

Time of Concentration Input Parameters Computed Time of Concentration Time of Concentration: 24.45 min

Sheet Flow Input Parameters Top Elevation: 2567.06 ft Bottom Elevation: 2565.19 ft Length: 30.60 ft

See HDS-2 Table 2.1 2 yr, 24 hr precip: 4.5840 in

Sheet Flow Results Slope: 0.0611 ft/ft Time of Concentration: 0.25 min

Channel Flow Input Parameters Define as: Channel Calculation Channel Name: Channel Analysis Top Elevation: 2565.18 ft Bottom Elevation: 2563.36 ft Length: 365.01 ft Manning's n: 0.1500

Channel Flow Results Slope: 0.0050 ft/ft Velocity: 0.2514 ft/s

Determined by Channel or Curb & Gutter Calculator Time of Concentration: 24.20 min

Total Time of Concentration Time of Concentration: 24.45 min Final Iterated Solution

Report for channel used in Time of Concentration calculations

Channel Analysis: Channel Analysis Notes:

Result Parameters Depth: 0.2633 ft Area of Flow: 1.3303 ft^2

Wetted Perimeter: 6.1710 ft Hydraulic Radius: 0.2156 ft Average Velocity: 0.2514 ft/s Top Width: 6.1062 ft Froude Number: 0.0949 Critical Depth: 0.0589 ft Critical Velocity: 1.3399 ft/s Critical Slope: 0.8610 ft/ft Critical Top Width: 4.47 ft Calculated Max Shear Stress: 0.0821 lb/ft^2 Calculated Avg Shear Stress: 0.0673 lb/ft^2

Project Title: VanDuzen Designer:

Project Date: Monday, March 09, 2020 Project Units: U.S. Customary Units Notes:

Channel Analysis: Channel Analysis-rt.end Notes:

Result Parameters Depth: 0.2476 ft Area of Flow: 1.2356 ft^2 Wetted Perimeter: 6.0417 ft Hydraulic Radius: 0.2045 ft Average Velocity: 0.2428 ft/s Top Width: 5.9808 ft Froude Number: 0.0941 Critical Depth: 0.0549 ft Critical Velocity: 1.2954 ft/s Critical Slope: 0.8806 ft/ft Critical Top Width: 4.44 ft Calculated Max Shear Stress: 0.0773 lb/ft^2 Calculated Avg Shear Stress: 0.0638 lb/ft^2

Project Title: VanDuzen Designer:

Project Date: Monday, March 09, 2020 Project Units: U.S. Customary Units Notes:

Rational Analysis: Ditch-rt-postculvert Notes:

Rational Method Input Parameters Runoff Coefficient: 0.90 Basin Area: 0.2600 acres Rainfall Intensity: 1.80 in/hr Time of Concentration: 16.67 minutes Recurrence Year: 10 year

Rational Method Results Flowrate: 0.4 cfs

IDF Results 10 year IDF equation: i = 8.5416 / (Tc + 0.696393)^0.545111 Intensity: 1.8022 in/hr

Time of Concentration Input Parameters Computed Time of Concentration Time of Concentration: 16.67 min

Sheet Flow Input Parameters Top Elevation: 2570.06 ft Bottom Elevation: 2566.32 ft Length: 53.18 ft

See HDS-2 Table 2.1 2 yr, 24 hr precip: 4.5840 in

Sheet Flow Results Slope: 0.0703 ft/ft Time of Concentration: 0.37 min

Channel Flow Input Parameters Define as: Channel Calculation Channel Name: Channel Analysis Top Elevation: 2566.31 ft Bottom Elevation: 2564.98 ft Length: 265.97 ft Manning's n: 0.1500

Channel Flow Results Slope: 0.0050 ft/ft Velocity: 0.2720 ft/s

Determined by Channel or Curb & Gutter Calculator Time of Concentration: 16.30 min

Total Time of Concentration Time of Concentration: 16.67 min Final Iterated Solution

Report for channel used in Time of Concentration calculations

Channel Analysis: Channel Analysis Notes:

Result Parameters Depth: 0.3005 ft Area of Flow: 1.5631 ft^2

Wetted Perimeter: 6.4779 ft Hydraulic Radius: 0.2413 ft Average Velocity: 0.2720 ft/s Top Width: 6.4039 ft Froude Number: 0.0970 Critical Depth: 0.0689 ft Critical Velocity: 1.4426 ft/s Critical Slope: 0.8196 ft/ft Critical Top Width: 4.55 ft Calculated Max Shear Stress: 0.0938 lb/ft^2 Calculated Avg Shear Stress: 0.0753 lb/ft^2

Project Title: VanDuzen Designer:

Project Date: Monday, March 09, 2020 Project Units: U.S. Customary Units Notes:

Channel Analysis: Channel Analysis-rt.postculvert Notes:

Result Parameters Depth: 0.2908 ft Area of Flow: 1.5012 ft^2 Wetted Perimeter: 6.3976 ft Hydraulic Radius: 0.2346 ft Average Velocity: 0.2665 ft/s Top Width: 6.3260 ft Froude Number: 0.0964 Critical Depth: 0.0662 ft Critical Velocity: 1.4159 ft/s Critical Slope: 0.8299 ft/ft Critical Top Width: 4.53 ft Calculated Max Shear Stress: 0.0907 lb/ft^2 Calculated Avg Shear Stress: 0.0732 lb/ft^2

Project Title: VanDuzen Designer:

Project Date: Monday, March 09, 2020 Project Units: U.S. Customary Units Notes:

Rational Analysis: Ditch-rt-preculvert Notes:

Rational Method Input Parameters Runoff Coefficient: 0.90 Basin Area: 0.2800 acres Rainfall Intensity: 1.90 in/hr Time of Concentration: 15.12 minutes Recurrence Year: 10 year

Rational Method Results Flowrate: 0.5 cfs

IDF Results 10 year IDF equation: i = 8.5416 / (Tc + 0.696393)^0.545111 Intensity: 1.8961 in/hr

Time of Concentration Input Parameters Computed Time of Concentration Time of Concentration: 15.12 min

Sheet Flow Input Parameters Top Elevation: 2571.43 ft Bottom Elevation: 2567.67 ft Length: 37.98 ft

See HDS-2 Table 2.1 2 yr, 24 hr precip: 4.5840 in

Sheet Flow Results Slope: 0.0990 ft/ft Time of Concentration: 0.25 min

Channel Flow Input Parameters Define as: Channel Calculation Channel Name: Channel Analysis Top Elevation: 2567.66 ft Bottom Elevation: 2566.42 ft Length: 252.17 ft Manning's n: 0.1500

Channel Flow Results Slope: 0.0049 ft/ft Velocity: 0.2825 ft/s

Determined by Channel or Curb & Gutter Calculator Time of Concentration: 14.88 min

Total Time of Concentration Time of Concentration: 15.12 min Final Iterated Solution

Report for channel used in Time of Concentration calculations

Channel Analysis: Channel Analysis Notes:

Result Parameters Depth: 0.3224 ft Area of Flow: 1.7053 ft^2

Wetted Perimeter: 6.6585 ft Hydraulic Radius: 0.2561 ft Average Velocity: 0.2825 ft/s Top Width: 6.5791 ft Froude Number: 0.0978 Critical Depth: 0.0747 ft Critical Velocity: 1.4996 ft/s Critical Slope: 0.8005 ft/ft Critical Top Width: 4.60 ft Calculated Max Shear Stress: 0.1006 lb/ft^2 Calculated Avg Shear Stress: 0.0799 lb/ft^2

Project Title: VanDuzen Designer:

Project Date: Monday, March 09, 2020 Project Units: U.S. Customary Units Notes:

Channel Analysis: Channel Analysis-preculvert Notes:

Result Parameters Depth: 0.3291 ft Area of Flow: 1.7495 ft^2 Wetted Perimeter: 6.7137 ft Hydraulic Radius: 0.2606 ft Average Velocity: 0.2858 ft/s Top Width: 6.6327 ft Froude Number: 0.0981 Critical Depth: 0.0766 ft Critical Velocity: 1.5167 ft/s Critical Slope: 0.7945 ft/ft Critical Top Width: 4.61 ft Calculated Max Shear Stress: 0.1027 lb/ft^2 Calculated Avg Shear Stress: 0.0813 lb/ft^2

Appendix F – HY‐8 Reports

HY-8 Culvert Analysis Report

Crossing Discharge Data Discharge Selection Method: Specify Minimum, Design, and Maximum Flow Minimum Flow: 0.01 cfs Design Flow: 0.5 cfs Maximum Flow: 1 cfs

Table 1 - Summary of Culvert Flows at Crossing: Driveway

Headwater Elevation

(ft) Total Discharge (cfs) Culvert 1 Discharge

(cfs) Roadway Discharge

(cfs) Iterations

2566.56 0.01 0.01 0.00 1

2566.63 0.11 0.11 0.00 1

2566.72 0.21 0.21 0.00 1

2566.78 0.31 0.31 0.00 1

2566.84 0.41 0.41 0.00 1

2566.89 0.50 0.50 0.00 1

2566.94 0.60 0.60 0.00 1

2566.99 0.70 0.70 0.00 1

2567.03 0.80 0.80 0.00 1

2567.07 0.90 0.90 0.00 1

2567.11 1.00 1.00 0.00 1

2568.20 3.18 3.18 0.00 Overtopping

Rating Curve Plot for Crossing: Driveway

Table 2 - Culvert Summary Table: Culvert 1

Straight Culvert

Inlet Elevation (invert): 2566.42 ft, Outlet Elevation (invert): 2566.31 ft

Culvert Length: 22.51 ft, Culvert Slope: 0.0049

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)

0.01 0.01 2566.56 0.137 0.065 3-M2t 0.058 0.011 0.034 0.034 1.224 0.072

0.11 0.11 2566.63 0.186 0.214 3-M2t 0.187 0.131 0.138 0.138 1.658 0.173

0.21 0.21 2566.72 0.256 0.297 3-M2t 0.258 0.182 0.201 0.201 1.848 0.215

0.31 0.31 2566.78 0.314 0.364 3-M2t 0.316 0.225 0.251 0.251 1.993 0.245

0.41 0.41 2566.84 0.361 0.423 3-M2t 0.366 0.261 0.293 0.293 2.115 0.268

0.50 0.50 2566.89 0.403 0.472 3-M2t 0.410 0.289 0.329 0.329 2.220 0.286

0.60 0.60 2566.94 0.445 0.522 3-M2t 0.456 0.320 0.365 0.365 2.328 0.303

0.70 0.70 2566.99 0.483 0.567 3-M2t 0.499 0.344 0.397 0.397 2.424 0.317

0.80 0.80 2567.03 0.520 0.610 3-M2t 0.540 0.371 0.426 0.426 2.514 0.330

0.90 0.90 2567.07 0.555 0.651 3-M2t 0.582 0.396 0.453 0.453 2.602 0.342

1.00 1.00 2567.11 0.590 0.691 3-M2t 0.624 0.419 0.480 0.480 2.687 0.352

Culvert Performance Curve Plot: Culvert 1

Water Surface Profile Plot for Culvert: Culvert 1

Site Data - Culvert 1 Site Data Option: Culvert Invert Data Inlet Station: 1477.17 ft Inlet Elevation: 2566.42 ft Outlet Station: 1499.68 ft Outlet Elevation: 2566.31 ft Number of Barrels: 1

Culvert Data Summary - Culvert 1 Barrel Shape: Circular Barrel Diameter: 1.00 ft Barrel Material: Corrugated Steel Embedment: 0.00 in Barrel Manning's n: 0.0240 Culvert Type: Straight Inlet Configuration: Square Edge with Headwall Inlet Depression: None

Table 3 - Downstream Channel Rating Curve (Crossing: Driveway)

Tailwater Channel Data - Driveway Tailwater Channel Option: Trapezoidal Channel Bottom Width: 4.00 ft Side Slope (H:V): 4.00 (_:1) Channel Slope: 0.0050 Channel Manning's n: 0.1500 Channel Invert Elevation: 2566.31 ft

Roadway Data for Crossing: Driveway Roadway Profile Shape: Constant Roadway Elevation Crest Length: 100.00 ft Crest Elevation: 2568.20 ft Roadway Surface: Paved Roadway Top Width: 30.00 ft

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

0.01 2566.34 0.03 0.07 0.01 0.07

0.11 2566.45 0.14 0.17 0.04 0.09

0.21 2566.51 0.20 0.22 0.06 0.09

0.31 2566.56 0.25 0.24 0.08 0.09

0.41 2566.60 0.29 0.27 0.09 0.10

0.50 2566.64 0.33 0.29 0.10 0.10

0.60 2566.68 0.37 0.30 0.11 0.10

0.70 2566.71 0.40 0.32 0.12 0.10

0.80 2566.74 0.43 0.33 0.13 0.10

0.90 2566.76 0.45 0.34 0.14 0.10

1.00 2566.79 0.48 0.35 0.15 0.10

Appendix G – Corrosion

H ydrology and H ydraulics D ecem ber 2012

R oadw ay H ydraulics

7-53

Exhibit 7.3-B

ESTIM

TIN

STEEL PIPE SER

VIC

ES LIFE

FEDERAL LANDS HIGHWAY MODIFIED CALIFORNIA METHOD CHART FOR

ESTIMATING SERVICE LIFE OF PLAIN GALVANIZED STEEL CULVERTS

Service Life Estimation Chart for Average Service Life of Plain Galvanized Culverts

NOTES:

1. The curves in this Chart are based on the data in FHWA-FLP-91-006 which uses the factors in California Test 643, “Method for Estimating the Service Life of Steel Culverts”. These factors increased the estimated service life by 25% after first perforation.

2. The Chart has also been modified to reflect a minimum metal thickness of 0.064 inch or 16 gage [1.63 mm]

3. Under conditions with pH between 5 and 9, and above R 1500, the average service life determined for plain galvanized culverts should be multiplied by 2.0 for Aluminum coated steel, (Type 2).

THICKNESS FACTORS

0.168

4.27 2.6

Note: Multiply the average Service Life by the Thickness Factor

0.138

3.51 2.2

0.109

2.77 1.7

0.079

2.01 1.2

0.064

1.63 1.0

0.052

1.32 0.8

THICKNESS, inch

GAGE

THICKNESS, mm

FACTOR

11,000

6.61

1.2 x 45 = 54 years

	2020-12-08T16:34:38-0800
Howard, Travis AAB00050626

File details come from the government source that posted it. Updated Jan 28, 2021.