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A Guide to ComputerSoftware Tools for
Culvert Designand Analysis
United StatesDepartment ofAgriculture
Forest Service
Technology &DevelopmentProgram
7700—Transportation System2500—Watershed and AirNovember 19999977 1806—SDTDC
ii
iii
A GUIDE TO COMPUTERSOFTWARE TOOLS FORCULVERT DESIGN ANDANALYSIS
Kemset Moore, Hydrologist, E.I.T.Michael J. Furniss, HydrologistSam A. Flanagan, GeologistMichael A. Love, E.I.T.Six Rivers National ForestPacific Southwest RegionJeff Moll, P.E.Senior Project Leader
San Dimas Technology and Development CenterSan Dimas, California
November 1999
Information contained in this document has been developedfor the guidance of employees of the Forest Service, USDA, itscontractors, and cooperating Federal and State agencies. TheDepartment of Agriculture assumes no responsibility for theinterpretation or use of this information by other than its ownemployees. The use of trade, firm, or corporation names is forthe information and convenience of the reader. Such use doesnot constitute an official evaluation, conclusion, recommendation,endorsement, or approval of any product or service to theexclusion of others that may be suitable.
The United States Department of Agriculture (USDA) prohibitsdiscrimination in all its programs and activities on the basis ofrace, color, national origin, sex, religion, age, disability, politicalbeliefs, sexual orientation, or marital or family status. (Not allprohibited bases apply to all programs.) Persons with disabilitieswho require alternative means for communication of programinformation (Braille, large print, audiotape, etc.) should contactUSDA’s TARGET Center at 202-720-2600 (voice and TDD).
To file a complaint of discrimination, write USDA, Director,Office of Civil Right, Room 326-W, Whitten Building, 1400Independence Avenue, SW, Washington, D.C. 20250-9410 orcall 202-720-5964 (voice and TDD). USDA is an equal opportunityprovider and employer.
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Contents
INTRODUCTION................................................................................................................................... 1
OBJECTIVES ........................................................................................................................................ 1
SCOPE.................................................................................................................................................. 1
CULVERT DESIGN AND ANALYSIS .................................................................................................... 2
Goals ............................................................................................................................................. 2
Design Criteria ............................................................................................................................... 2
Design Phases ............................................................................................................................... 2
Phase 1-Hydrology ................................................................................................................. 4
Phase 2-Culvert Specifications and Site Considerations ........................................................ 4
Phase 3-Culvert Hydraulics .................................................................................................... 4
INFORMATION ACQUISITION ............................................................................................................. 5
INFORMATION ORGANIZATION ......................................................................................................... 5
FINDINGS ............................................................................................................................................. 5
DISCUSSION ........................................................................................................................................ 8
A DECISION METHODOLOGY ............................................................................................................ 11
LITERATURE CITED ............................................................................................................................ 12
APPENDIX A ......................................................................................................................................... 15
APPENDIX B......................................................................................................................................... 19
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1
INTRODUCTION
Forest engineers and hydrologists regularlycalculate design culvert dimensions for use inwildland road-stream crossings. This projectinvestigates existing software tools to aid resourcemanagers in culvert design and analysisrequirements for low volume forest roads.
Computer models can make culvert design andanalysis less cumbersome, but not all softwareproducts will meet the designer’s needs.
How to Use This Guide
This guide is a snapshot of information on softwaretools for culvert design and analysis gathered asof June 1998. To select a cost-effective softwareproduct that meets design needs, the reader can:
1. Look sequentially at all the tables, particularlythe product review summary, which comparesall the products. The tables, in order, are
Table 1. Stream Crossing Culvert DesignConsiderations
Table 2. Factors for Inlet and OutletControl
Table 3. Product Reviews
Table 4. Culvert Product by Focus
Table 5. Input Data
Table 6. Output Data
Table 7. Criteria Weighting Factors
Table 8. Selection Matrix Example
2. Read the paper.
3. Follow the decision matrix methodologysuggestions located in appendix A.
A glossary of terms and notations is presented inappendix B, and a decision matrix with selectedcriteria is presented in appendix A.
OBJECTIVES
The objectives of this study were to providebackground information on culvert design andanalysis and to locate and inventory existing
computer software for use in culvert design andanalysis. Products were evaluated with twoquestions in mind: what does the product do, andhow does it do it?
SCOPE
This paper
• Compares commercial software applicationsused to size culverts
• Considers products for use on DOS, Windows,Macintosh, and UNIX operating systems
• Evaluates programs designed for use asstand-alone products
• Includes larger programs designed for river orwatershed system analysis containing strongculvert modeling components
• Contains a glossary of culvert design andanalysis terms
• Includes a system for making a softwarechoice based on user needs
but does not
• Consider watershed modeling tools withoutculvert components, geographic informationsystems, engineering computer-aided designpackages without a culvert component, stormand sanitary pipe modeling, or
• Make recommendations or ratings of products.
Because no central organized database forlocating software exists, it was necessary todevelop sources of software information. Thesesources included interviews with U.S. Departmentof Agriculture (USDA) Forest Service personnel;private and transportation agency hydraulic andhydrologic engineers; on-line Internet searches ofWorld Wide Web sites; software catalogs; literatureand book reviews; trade journals; professionalmagazines and product literature. This guide is nota comprehensive list of products, but does give agood overview of features found on current market
2
products. The guide is not complete; new softwareis constantly being developed and current productsare being upgraded, making a definitivecomparison of culvert design software impractical.
CULVERT DESIGN AND ANALYSIS
Goals
The principal goal of culvert design is to determinethe size, alignment, and functionality of the culvertwith respect to passage requirements. In additionto the flow of water, a culvert must pass woodydebris and sediment and allow passage of aquaticspecies. The term “size” refers to the dimensionsof the barrel, including the culvert diameter andlength. Alignment considers the culvert placement,usually horizontal, respective to stream flowdirection and road centerline. Functionality refersto the culvert operations under given conditionsand includes culvert hydraulic capacity. Additionalgoals of design include structural stability,durability, cost, ease of maintenance and safety(Gribben 1997).
According to Donahue and Howard (1987), thegreatest source of error in culvert design is indesign flow analysis. The complex array ofvariables that influence runoff, statisticaluncertainties associated with hydrologic analysis,and a lack of comprehensive assessmentmethodology contribute to this error. Given thisinitial source of variability, a design goal is tominimize additional error wherever possible,particularly in the selection of culvert size and thedetermination of outlet velocity.
Design Criteria
The selection of design criteria for a particularculvert is a function of many interacting factorsincluding culvert hydraulics, watershed hydrology,and land management activities, according toPyles (1989). Design criteria for a culvertinstallation are unique to a given installation;however, the list of items in table 1 should beconsidered for any culvert installation (Pyles 1989).Not all the items will pertain to every installation.
Design Phases
Three phases are considered in culvert design.Phase one evaluates the hydrologic demands
placed on the culvert. Phase two looks at culvertspecifications and site considerations. And phasethree evaluates culvert hydraulics. In addition to theAmerican Iron and Steel Institute (1994 and 1995)handbooks on drainage design, Gribben (1997)and Ramsbottom et al. (1997) are comprehensivesources of complete culvert design theory withapplications. The following schematic (figure 1)combined with terms in the glossary (appendix B)illustrate concepts and definitions used in culvertdesign and by the software products.
Phase 1-HydrologyDesign begins with the choice of a design storm,a parameter usually determined by policy or rules(for example, the 100-year design storm). After thedesign storm is determined, the discharge throughthe culvert can be computed. In some instances,this discharge may be chosen by the designer orvaried to determine culvert performance. Designstorm estimators include the Rational Method,regional regression equations, and the SCS(National Resource Conservation Service) curvemethod. American Iron and Steel Institute (1994and 1995) summarizes the many methods. Peakvolumetric flow rate, which is conveyed through theculvert, is ultimately a result of rainfall intensity andduration. This information can be in the form ofactual rainfall events, representative designstorms, intensity duration frequency curves, or astatistical analysis of rainfall records.
For culverts on steep forested wildlands, debrisand sediment plugging cause culvert failure morefrequently than peak flow capacity exceedence.(Furniss et al. 1998). Because the softwarereviewed in this paper incorporates flow rate as theinitial design criteria, careful and judicious use ofsoftware for culverts on steep slopes isencouraged.
Phase 2-Culvert Specifications and SiteConsiderationsAn existing drainage or the need for ditch relief ona road segment usually dictates culvert location.
The allowable headwater depth (AWD) is themaximum depth of ponded water upstream of theculvert inlet measured vertically from the invert and
3
Figure 1—Schematic design of culvert in longitudinal cross section.
Table 1—Stream crossing culvert design considerations (adapted from Pyles 1989).
Category Item
Peak Flow Events Pipe sizeSlopeEntrance typeFreeboardPondingInlet/outlet controlRainfallWatershed modeling
Fish Passage Migration periodWater velocityPipe inlet/outlet geometryWater depthStability of outlet pool
Maintenance Woody debrisBedloadMaintenance fundingCurrent maintenance cycleScour effects
Economics Life spanCosts of environmental and structural damage from failureInstallation costsMaintenance costsReplacement costs
Legal Requirements Forest practice regulationsConstruction timing
Culvert inlet Culvert outlet
Crown CrownRoad prism
InvertInvert
DHW
TWSo
HW - Headwater elevationTW - Tailwater elevationL - Barrel lengthSo - Slope of culvertD - Diameter of culvert barrel
L
Profile of culvert, inlet control, inlet not submerged, and projecting inlet and outlet
R9801010
4
controls hydraulic design. AWD may bedetermined by the depth of fill over the culvert,which is dictated by local topography and roadwaygeometry and standards. Frequently, a headwater(HW) to culvert diameter (D) ratio is specified, suchas HW/D = 1, which places the allowableheadwater elevation at the inlet crown of theculvert.
The choice of pipe material, shape, and size maybe fixed by economics, availability, site conditions(fill, bedrock, bedload), and fish passage concerns(Gribben 1997).
Site parameters important in the design of culvertsinclude the length and slope of the culvertalignment, allowable headwater, fill depth, andeffects on inlet geometry. Fill depth is determinedby design loads, local topography, roadwaygeometry, and standards.
Phase 3-Culvert HydraulicsCulvert hydraulic modeling conventions assumethat the flow through a culvert is steady andincompressible with constant density (Donahueand Howard 1987). The cross sectional area of theculvert is assumed not to change. One of thesoftware products evaluated will allow changes inslope within a culvert, otherwise, the slope isassumed constant.
The capacity of a culvert can be affected byupstream and downstream conditions and by thehydraulic characteristics of the culvert.Combinations of these factors can be grouped intotwo types of flow conditions in culverts, inlet controland outlet control (table 2). These types of flowcontrol can also be defined by the location of thecontrol section at the culvert inlet or outlet.
Inlet control occurs when the culvert barrel iscapable of conveying more flow than the culvertinlet will accept. Water can flow out of the culvertfaster than it can enter the inlet. Critical depthoccurs at or near the entrance to the culvert, andthe flow downstream from the inlet is supercritical.Hydraulic characteristics of the downstreamchannel do not affect culvert capacity. Mostculverts, except those in flat terrain (less than 3percent), are designed to operate under inletcontrolled conditions (Ballinger and Drake 1995).
Because the capacity is controlled by entrancegeometry, minor modifications to the culvertentrance can affect hydraulic capacity with bothinlet or outlet control.
Outlet control is physically more complex than inletcontrol (table 2). Outlet control occurs when theculvert barrel is not capable of conveying as muchflow as the inlet opening will accept. Water canenter the culvert faster than it can flow through theculvert. Culvert discharge, influenced by the samefactors as inlet control, is also modified by tailwaterelevation and barrel characteristics. Barrelcharacteristics include culvert roughness, crosssectional area, length, shape, and slope. Whenculverts are operating in outlet control, changes inbarrel characteristics or tailwater elevation willaffect capacity. Hence, friction must be consideredin calculating discharge and velocity (AmericanIron and Steel Institute 1994).
Culvert design is an iterative process. Results fromhydraulic analysis might indicate that pipe size,shape, number, and materials produce conditionsunacceptable to the designer. If this is the case,the designer starts over basing the next design onresults obtained from the previous analysis. Theapproach used by Normann (1985), which isincorporated into many of the software products(see table 3), is to analyze a culvert for both typesof flow control. Adequate performance under theleast favorable conditions is ensured by designingfor the control that is least efficient at moving wateras indicated by the higher of the two (inlet or outletcontrol) inlet headwater elevations. The higherelevation requires more energy to pass a given flowand is, therefore, the design elevation.
ACQUIRING INFORMATION
The above criteria serve as comparisons for eachsoftware product. Information on each product wasgathered from software use, interviews, productliterature, and training.
Although every effort was made for product reviewconsistency, information may differ because not allproducts experienced the same level of review. Thepotential exists for uneven analysis as not allsoftware products were reviewed from the full
5
commercial product. See Review Level in table 3,Product Reviews, for comparison of review levels.To ensure accuracy, the product developer anddistributor checked all reviews.
Each software product was evaluated using a Dell486DE with 24 MB of RAM, 1 GB hard drive, CD-ROM or Macintosh 8100 with 36 MB of RAM, 1 GBhard drive, running System 8.0.
INFORMATION ORGANIZATION
Information on each reviewed product is coded intoa two-page summary report. These reports will beavailable by the summer of 1999 on the USDAForest Service Intranet at http://fsweb.sdtdc.wo.fs.fed.us/programs/eng/w-r/eccs.Detailed information on price, platforms, names,addresses (web sites, e-mail), algorithms, sourcecode availability, modeling techniques, andremarks are noted. Input data requirements,application results, and output formats arecompiled. All products reviewed are summarizedbelow in tables 3 and 4 for a quick comparison ofcosts, operating systems, application focus, andsolution methodology. Product sources, vendor,and developer information for each product isfound in appendix A.
FINDINGS
Thirty-three products were considered forinclusion. Thirteen of these are not currentlyavailable or appropriate. This resulted in a reviewof twenty products, which are summarized in table3. Culvert hydraulic design products, complex CADsoftware, and watershed modeling software with
Table 2—Factors for inlet and outlet control.
Factor Inlet control Outlet control
Headwater elevation X XInlet area X XInlet edge configuration X XInlet shape X XCulvert roughness XCulvert shape XCulvert area XCulvert length XCulvert slope * XTailwater elevation X*Culvert slope affects inlet control performance to a small degree, but may be neglected (Normann et al. 1985).
a culvert design component make up the majorityof products located to date.
Most culvert design and analysis softwareprograms are based on Federal HighwayAdministration (FHWA) research, primarilyNormann (1985) (table 3). The cost of theseproducts ranges widely from free to $795.00.
Software products perform a variety of functionsand give the culvert modeler a wide choice offeatures. Not every product accomplishes all goals,so it is best to determine the culvert design needsfirst, compare product features, and then weightcosts. Most products provide a choice of units ofmeasure and options for defining hydrology. A fewsoftware products will model roads along withculverts to provide the opportunity for determiningcapacity exceedance. Tables 5 and 6 summarizeall input and output features for each product.
DISCUSSION
Software is capable of returning extremely preciseresults that can be misleading. Culvert software fordesign and analysis requires informed,experienced use, incorporating awareness toassumptions and “bugs” embedded in products.For example, pipe arch definitions differ amongsoftware products. A pipe arch described by asoftware product may be a structural plate pipearch, ellipse set below grade, open bottomedculvert, or a prefabricated ‘squashed pipe.’ Thisinformation may show in cross-sectional areacomputational differences, variations in Manning’sn through a closed or open bottom arch, visualsketches, or results. The software product’s
6
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WS
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dow
s 9X
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dow
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A
lgor
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rces
Bod
hain
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969)
Nor
man
n (1
985)
Nor
man
n (1
985)
Pie
hl e
t al.
(198
8)
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man
n (1
985)
Cal
iforn
ia H
ighw
ay o
rM
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ng’s
equ
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man
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985)
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raul
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eory
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ower
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man
n (1
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lke
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91),
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lke
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3)
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man
n (1
985)
Nor
man
n (1
985)
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man
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985)
unkn
own
Tabl
e 3—
Pro
duct
rev
iew
s.
7
Rev
iew
Lev
el*
Rev
iew
cod
eIn
form
atio
n so
urce
Det
ails
1In
terv
iew
sP
rodu
ct d
evel
oper
, mar
ketin
g, u
sers
, sp
ecia
lists
2Li
tera
ture
Pub
licat
ions
, pro
duct
lite
ratu
re,
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Web
pag
es3
Test
ing
Dem
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valu
atio
n co
py, f
ull c
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RIV
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1 2
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vert
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ysis
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anal
ysis
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vert
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and
anal
ysis
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er m
odel
ing
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vert
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pone
nt
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vert
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anal
ysis
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f Hyd
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exas
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/9X
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s 9X
, NT
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dow
s 9X
, DO
S fo
rea
rlier
Hae
stad
ver
sion
A
lgor
ithm
sou
rces
Nor
man
n (1
985)
Gen
eral
hyd
raul
ic th
eory
Nor
man
n (1
985)
Nor
man
n (1
985)
Nor
man
n (
1985
), H
EC
-2
HE
C-1
2 an
d H
EC
-22
Tabl
e 3—
Con
tinue
d.
8
definition of a pipe arch must be in agreement withthe culvert designer’s concept of a pipe arch.
System compatibility is critical to successful use ofa software product, so it is very important to matchsoftware product to available computer equipment.There is a difference between a product that runsin DOS and one that runs in the DOS emulatormode of Windows 95. True DOS software is batchinput and will not run in Windows.
Cost of the software product is a factor in anyacquisition decision. In addition to the initialsoftware purchase, the culvert designer shouldconsider any hidden costs that may be associatedwith the initial purchase. If new systemrequirements or hardware such as a CD-ROMdrive is necessary, these costs should be taken intoaccount. Additional expenses may be associatedwith product support, or user manuals. Finally,costs associated with learning to use the productalso need to be considered.
Be careful of “feature bloat,” which is defined asunnecessary and expensive additions to products.
A user-friendly product running faster and requiringless disk space is more desirable than one withmany unnecessary features. The additions makethe product more difficult to use. Product supportand a clear and concise users’ manual are vital tothe successful and continued usage of a softwareproduct. They are also more important thanexpensive features. Some of the productsreviewed are complex and include several designfeatures. If, after careful evaluation, a total rivermodeling system with culvert design capabilitiesand CAD features are needed in a softwareproduct, the cost may be justified.
A DECISION METHODOLOGY
One approach to this guide is to combine productinformation with specific needs as determined bythe reader. A decision matrix with suggestedcriteria can be found in appendix A. The followingprocedure guides the user through this decisionprocess.
Software selection begins with the resourcemanager, who defines a list of needs and
Table 4—Culvert product by focus.
Culvert design and analysis Watershed/river modeling Specialty culvert designwith culvert component and analysis
CAP-Culvert Analysis CHAN v.2* Xing-Risk
CulvertMaster* Eagle Point Watershed* FishPass
DrainCalc Eagle Point Water Surface Profiling FishXing
Drainage Calculator HEC-RAS v 2.2*
HydroCalc for Windows 95 v. 1.2a* HydroCAD
HY-8, Culvert Analysis* RiverCAD*
HYDrain*
HydroCulv v.1
MacCulvert*
Quick PipePro*
THYSYS
*Incorporates Normann (1985) as algorithm source.
9
Sof
twar
e pr
oduc
t will
inco
rpor
ate
the
follo
win
g da
ta:
Sof
twar
e N
ame:
Unit choice Peak flowFlow rateHydrograph User defined rainfall/hydrograph
Roadway elevationRoadway width Pavement choice PondingBank slopeRiprapDepth of fill Uses weir equations
Non-overtopping choice
Maximum allowable headwater
Inlet elevation Inlet configuationInlet coefficient Outlet elevation Outlet configurationOutlet coefficentMaterial choicesCorrugation choicesTailwater configurationShape choices Coded size User defined size SlopeBreaks in slope Length of culvert Alignment FallNegative elevationsManning's n Natural channel user defined
Other channel shapesMultiple barrels Combine multiple barrel elevations
Combine multiple barrel shapes
Watershed modelingFish swimming abilityValues and consequences
CA
P -
Cul
vert
Ana
lysi
s P
rogr
amX
XX
XX
XX
XX
XX
XX
XX
XX
XX
X
CH
AN
v.2
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
X
Cul
vert
Mas
ter
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
Xin
g-R
isk
XX
XX
XX
XX
XX
XX
X
Dra
inag
e C
alcu
lato
rX
XX
Dra
inC
alc
XX
XX
XX
XX
XX
X
Eag
le P
oint
Wat
ersh
ed
Mod
elin
g v7
.0S
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
Eag
le P
oint
Wat
er
Sur
face
Pro
filin
gX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
X
Fish
Pas
sX
XX
XX
XX
XX
X
Fish
Xin
gX
XX
XX
XX
XX
XX
XX
XX
X
HE
C R
AS
v 2
.2X
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
X
HY
-8 (C
ulve
rt A
naly
sis)
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
X
HY
Dra
inX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
Hyd
roC
AD
XX
XX
XX
XX
XX
XX
XX
XX
XX
X
Hyd
roC
alc
Hyd
raul
ics
Win
95 v
1.2a
XX
XX
XX
XX
XX
XX
XX
XX
X
Hyd
roC
ulv
v1.0
2X
XX
XX
XX
XX
XX
XX
Mac
Cul
vert
XX
XX
XX
XX
XX
XX
XX
XX
X
Qui
ck P
ipe
Pro
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
X
RIV
ER
CA
DX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
X
THY
SY
SX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
X
Tabl
e 5—
Inpu
t dat
a.
10
Sof
twar
e N
ame:
Size
SlopeInlet controlled tailwater depth
Inlet controlled headwater depth
Inlet controlled discharge
Outlet controlled tailwater depth
Outlet controlled headwater depth
Outlet controlled discharge
Slope type Flow regime Energy grade lineWater depth Flow areaWetted perimeterHydraulic radius Water srface topwidth
Froude number Velocity at inlet Velocity at outletTotal discharge Discharge over roadDischarge/barrelNormal depth Critical depth Critical slope Outlet scour Tractive force Rating curves Generates report
Copy/paste to other applications
Water surface profilePrint screen Flow duration curve Internal note padFish passage capabilitie
s
Environmental risk assessment
CA
P -
Cul
vert
Ana
lysi
s P
rogr
amX
XX
XX
XX
XX
XX
XX
XX
X
CH
AN
v.2
XX
XX
XX
XX
XX
XX
XX
Cul
vert
Mas
ter
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
X
Xin
g-R
isk
XX
XX
Dra
inag
e C
alcu
lato
rX
Dra
inC
alc
XX
XX
XX
XX
XX
Eag
le P
oint
W
ater
shed
Mod
elin
g v7
.0s
XX
XX
XX
XX
Eag
le P
oint
Wat
er S
urfa
ce
Pro
filin
gX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
Fish
Pas
sX
XX
XX
XX
XFi
shX
ing
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
HE
C R
AS
v 2
.2X
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
HY
-8 (C
ulve
rt A
naly
sis)
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
X
HY
Dra
inX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
X
Hyd
roC
AD
XX
XX
XX
XX
Hyd
roC
alc
Hyd
raul
ics
Win
95 v
1.2a
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
Hyd
roC
ulv
v1.0
2X
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
X
Mac
Cul
vert
XX
XX
XX
XX
XX
XX
Qui
ck P
ipe
Pro
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
X
RIV
ER
CA
DX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
THY
SY
SX
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
Sof
twar
e pr
oduc
t ret
urns
the
follo
win
g da
ta:
Tabl
e 6—
Out
put d
ata.
11
requirements. Each product is examined orevaluated in terms of the users’ desired application.A list of criteria emerges from this step. A weight isassigned to each of these, with the more importantcriteria having a higher value. This approachrequires careful evaluation of weights, but the
WF Descriptive statement
2 = very desirable feature, must have
1 = necessary for operation of software
0 = not necessary or program does not contain this feature
Table 8—Selection matrix example.
WeightingRequirements based on list of criteria factor Product A Product B Product C
Rainfall modeling incorporating userdefined parameters 1 yes 1 no 0 yes 1
Inlet/ outlet control modeling 1 no 0 yes 1 yes 1
Model multiple culverts inparallel or in series 0 yes 0 yes 0 no 0
Fish swimming abilities incorporatedinto design capabilities 2 no 0 no 0 yes 2
Total points 1 1 4
Table 7—Criteria weighing factors.
Example: A simplified selection matrix might look like table 8. In this instance, the hydrologist researchingculvert software determines the following criteria are important and assigns relative weights to eachcriterion. If a product meets a selection criterion, the associated weighting factor
users can tailor the selection process to theirspecific needs. If the product has that feature, thechosen weight is assigned. If the product does nothave the desired feature, a score of zero isassigned. A suggested weighing factor (WF) foreach criterion is shown in table 7:
12
LITERATURE CITED
American Iron and Steel Institute. 1994. Handbook of Steel Drainage and Highway Construction Products.518 p.
American Society of Civil Engineers, Task Committee on Software Evaluation of the Technical Council onComputer Practices. 1989. Guide for Evaluating Engineering Software. American Society of CivilEngineers, New York, New York, 121 p.
Ballinger, Craig A., and Patricia G. Drake. 1995. Culvert Repair Practices Manual: Volume I. A-RD-94-096.
Behlke, Charles E. 1993. “Fundamentals of Culvert Design for Passage of Weak-Swimming Fish, SoftwareDocumentation.” FHWA-AK-RD-90-10.
Behlke, Charles E., Douglas L. Kane, Robert F. McLean, and Michael D. Travis. 1991. Fundamentals ofCulvert Design for Passage of Weak-Swimming Fish. Final Report. FHWA-AK-RD-90-10.
Bodhaine, G.L. 1969. “Measurement of Peak Discharge at Culverts by Indirect Methods.” U.S. GeologicalSurvey Techniques of Water-Resources Investigations. Book 3, Chapter A3.
California Department of Transportation. 1990. Highway Design Drainage Design. In Highway Design Manual.Sacramento CA. Chapters 800-890.
Donahue, John P., and Andrew F. Howard. 1987. “Hydraulic Design of Culverts on Forest Roads.” CanadianJournal of Forest Research. Volume 17, p 1545-1551.
Fulford, J.M. 1995. User’s guide to the culvert analysis program. U.S. Geological Survey Open File Report95-137. 69 p.
Fulford, J.M., 1997. Revisions of the CAP program and OFR 95-137. 10 p.
Furniss, Michael J., Tyler S. Ledwith, Michael A. Love, Bryan C. McFadin, and Sam A. Flanagan. 1998.“Response of Road-Stream Crossings to Large Flood Events in the Washington, Oregon and NorthernCalifornia.” USDA Forest Service San Dimas Technology and Development Center. No. 9877-1806
Gribben, John E. 1997. Hydraulics and Hydrology for Stormwater Management. Delmar Publishers.
Hansen, William F. 1987. Some applications of flood frequency and risk information in forest management.In: Application of Frequency and Risk in Water Resources. Singh, V.P. ed. D. Reidel Publishing Company.
Haussman, Richard F., and Emerson W. Pruett, 1978. Permanent Logging Roads for Better WoodlotManagement. USDA Forest Service State and Private Forestry, Northeastern Area, Broomall,Pennsylvania. 43 p.
HEC. 1999. US Army Corps of Engineers, Hydrologic Engineering Center. 1999. http://www.wrc-hec.usace.army.mil
Helvey, J. David, and James N. Kochenderfer. 1988. Culvert Sizes Needed for Small Drainage Areas in theCentral Appalachians. Northern Journal of Applied Forestry. 5(2) 123-127.
Huber, W.C., and R. El. Dickinson. 1988. Storm Water Management Model, Version 4: User’s Manual.USEPA.
13
Myers, Glenford J. 1979. The Art of Software Testing. Wiley and Sons.
Nolan, Jeanne M., (ed.). 1984. Micro Software Evaluations. Knoll Information Management Services. Torrance,California, 176 p.
Normann, Jerome M., Robert J. Houghtalen, and Robert J. Johnston. 1985. Hydraulic Design of HighwayCulverts. Rep. No. FHWA-IP-15 HDS No. 5. McLean, Virginia: Federal Highway Administration. 272 p.
Parola, Arthur. 1987. Hydraulic Analysis of Culverts by Microcomputer. Pennsylvania State University. Master’sthesis. May 1987. 84 p.
Piehl, Bradley T., Marvin R. Pyles, and Robert L. Beschta. 1988. “Flow Capacity of Culverts on OregonCoast Range Forest Roads.” Water Resources Bulletin. 24 (3) 631-637.
Powers, Patrick D., and John F. Orsborn. 1985. Analysis of Barriers to Upstream Fish Migration: AnInvestigation of the Physical and Biological Conditions Affecting Fish Passage Success at Culvert andWaterfalls. Final Report Part 4 of 4. Albrook Hydraulics Laboratory, Department of Civil and EnvironmentalEngineering, Washington State University, Pullman, Washington 99164-3001. 119 p.
Pyles, Marvin, Arne E. Skaugset, and Terry Warhol. 1989. “Culvert Design and Performance on ForestRoads.” Proceedings of the 12th Annual Council on Forest Engineering, Coeur d’Alene, Idaho. August27-30, 1989. 82-87.
Ramsbottom, D., R. Day, and C. Rickard. 1997. Culvert Design Guide. Report 168. Construction IndustryResearch and Information Association, 6 Storey’s Gate, Westminster, London, SW1P 3AU, UnitedKingdom. 189 p. http://www.ciria.org.uk/ciria/ for ordering information.
Rowe, R. Robinson. 1943. New Chart for Culvert Design. California Division of Highways, Sacramento,California. Civil Engineering. p 544.
Schuster, Ervin G., Larry A. Leefers, and Joyce E. Thompson. 1993. A guide to computer-based analyticaltools for implementing National Forest Plans. Gen. Tech. Rep INT-296. Ogden UT: USDA Forest Service,Intermountain Research Station. 269 p.
14
15
UNIX Compatible X
DOS Compatible X
Windows Compatible X X X
Macintosh Compatible
Product support X X X X
Unit Choice X X X
Watershed Modeling X
Rainfall Modeling X X X X
Peak Flow X X X
Flow Rate / Discharge X X X
Roadway Modeling X X X
Normann (1985) basis forCulvert Modeling X X
Maximum AllowableHeadwater X X X
Inlet /Outlet Configurations X X X
Break in Slope
Alignment X X
Fall X X
Negative Elevation X X
Multiple Barrels X X X
Shape Choices X X X X
Corrugation Choices X
Channel Definition X X X X
Hydraulic Parameters X
Size Calculation X X
Slope Calculation X
Slope Type X
Inlet and Outlet Control X X X
Scour Prediction /Tractive Forces
Fish Passage
Culvert Exit Velocity X X X
Erosion Hazard /Risk Assessment X
Water Surface ProfileData/Graphics X X
Rating Curve Output X
Generates Report X X X X
Cost of Product as ofJune 1998 Free $459.00 $495.00 Free $8.00
Total
CHAN v.2 XING-RISK
APPENDIX A
Decision Matrix
SUGGESTED DECISIONCRITERIA
WEIGHTINGFACTOR
CAPCULVERTANALYSISPROGRAM
CULVERTMASTER
DRAINAGECALCULATOR
16
UNIX Compatible
DOS Compatible X X X X
Windows Compatible X X X X X
Macintosh Compatible
Product support X X X X
Unit Choice X X X
Watershed Modeling X X
Rainfall Modeling X X
Peak Flow X
Flow Rate / Discharge X X X X
Roadway Modeling X
Normann (1985) basisfor Culvert Modeling X
Maximum AllowableHeadwater X X X
Inlet and OutletConfigurations X X
Break in Slope
Alignment
Fall
Negative Elevation
Multiple Barrels X X X
Shape Choices X X X X
Corrugation Choices X X X X
Channel Definition X X X X X
Hydraulic Parameters X X
Size Calculation X
Slope Calculation X X
Slope Type X X
Inlet and Outlet Control X X
Scour Prediction /Tractive Forces X
Fish Passage X X
Culvert Exit Velocity X X X X
Erosion Hazard /Risk Assessment
Water Surface ProfileData/Graphics X X X
Rating Curve Output X X
Generates Report X X X X X
Cost of Product asof June 1998 $295.00 $800.00 $800.00 Free Free
Total
SUGGESTED DECISIONCRITERIA DRAINCALC
EAGLEPOINT
WATER SURFACEPROFILING
EAGLEPOINT
WATERSHEDMODELING
v7.0S
FISHPASS FISHXING
APPENDIX A — Continued.
WEIGHTINGFACTOR
17
UNIX Compatible
DOS Compatible X X X
Windows Compatible X X X X X
Macintosh Compatible
Product support X X X X X
Unit Choice X X X X X
Watershed Modeling X X
Rainfall Modeling X X X
Peak Flow X X X X
Flow Rate / Discharge X X X X X
Roadway Modeling X X X
Normann (1985) basis forCulvert Modeling X X X X
Maximum AllowableHeadwater X X X
Inlet and OutletConfigurations X X X X
Break in Slope
Alignment
Fall X X X
Negative Elevation X X
Multiple Barrels X X X X
Shape Choices X X X X X
Corrugation Choices X X
Channel Definition X X X X X
Size Calculation X X
Slope Calculation X X X X
Slope Type X
Hydraulic Parameters X X X X X
Inlet and Outlet Control X X X X
Scour Prediction /Tractive Forces X X X
Fish Passage
Culvert Exit Velocity X X X X X
Erosion Hazard /Risk Assessment
Water Surface ProfileData/Graphics X X X X
Rating Curve Output X X X X X
Generates Report X X X X X
Cost of Product as of Free to $120 to $145.00 to $195.00 to $29.00June 1998 $150.OO $145 $350.00 $1595.00
Total
SUGGESTED DECISIONCRITERIA
WEIGHTINGFACTOR
HECRAS v2.2 HY8 HYDRAIN HYDROCAD v5.0 HYDROCALC v1.2a
APPENDIX A — Continued.
18
UNIX Compatible
DOS Compatible X
Windows Compatible X X X X
Macintosh Compatible X
Product support X X X X
Unit Choice X X X X
Watershed Modeling X
Rainfall Modeling X
Peak Flow X
Flow Rate / Discharge X X X X X
Roadway Modeling X X X
Normann (1985) basis forCulvert Modeling X X X
Maximum AllowableHeadwater X X X X X
Inlet and OutletConfigurations X X
Break in Slope X
Alignment
Fall
Negative Elevation
Multiple Barrels X X X
Shape Choices X X X X X
Corrugation Choices X X
Channel Definition X X X X
Size Calculation X
Slope Calculation X X X X
Slope Type X X
Hydraulic Parameters X X X X
Inlet and Outlet Control X X X X X
Scour Prediction /Tractive Forces X X
Fish Passage
Culvert Exit Velocity X X X X X
Erosion Hazard /Risk Assessment
Water Surface ProfileData/Graphics X X
Rating Curve Output X X X X
Generates Report X X X X X
Cost of Product asof June 1998 Free Free to $100.00 $375.00 $2690.00 $5.00
Total
SUGGESTEDDECISION CRITERIA
WEIGHTINGFACTOR HYDROCULV v1.02 MacCULVERT
QUICKPIPEPRO
RIVERCADTHYSYS
CULVERT v1.1
APPENDIX A — Continued.
19
APPENDIX B
GLOSSARY OF TERMS AND NOTATIONS
Placement of the culvert with respect to the streamflow and roadcrossing.
Allowable depth of water immediately upstream of a culvert,measured from the invert at the first full cross section of the culvert.A design criteria.
The maximum permissible depth of water surface immediatelyupstream of culvert at the design discharge, measured from adatum. Note: datum may differ between software applications;measured from culvert invert, or another datum.
Structural plate corrugated steel pipe formed to an arch shape.The invert may be the natural stream bed or any other suitablematerial, but is not integral with the steel arch. See pipe arch forcomparison.
The rise of water level upstream due to a downstream obstructionor channel confluence or constriction.
Water surface elevation for gradually varied flow, where changesin velocity occur very slowly, with negligible acceleration. Unitsare in length.
The effect that changes in flow rate or water depth have onupstream hydraulic conditions. Backwater effects can only occurin subcritical flow.
Obstruction, usually wood, concrete, or metal, placed inside aculvert to deflect and check the flow of water for fish passage.
Sediments, rocks, and boulders not in suspension, but rolled ordrawn along a stream bottom by force of water movement.
A flare on the inlet edge of a culvert to improve efficiency orcapacity of inlet controlled culverts, reduces the inlet coefficientKe.
Short segment of closed conduit, rectangular in cross-section.
The effective carrying ability of a drainage structure. Measuredin volume per time.
Percentage of gross rainfall that appears as runoff. Also ratio ofrunoff to depth of rainfall. Used in the Rational method forcomputing design discharge.
alignment
Note: These definitions are specific to the subject of this report.
allowable headwater depth (AHD)
allowable headwater elevation(AHE)
arch
backwater
backwater curve
backwater effect
baffle
bedload
beveled inlet
box culvert
capacity (hydraulic)
coefficient of runoff
20
competent velocity The velocity of water that can just move a specified type or sizeof streambed material.
Galvanized steel or aluminum sheet metal formed to finishedshape by the fabricator.
Providing the optimum effect at the most reasonable cost.
Depth of flow at which specific energy is minimum for a given flow.Not affected by downstream phenomenon.
Flow at critical depth, where the sum of the velocity head and thestatic head is at a minimum. Flow with Froude number of 1.
Slope of channel or culvert when normal depth equals criticaldepth. The slope at which a maximum flow will occur at minimumenergy.
Mean water velocity at critical depth.
A hydraulically short conduit that conveys stream flow, sediment,debris, and aquatic species through a roadway embankment orpast some other type of flow obstruction.
Floating, suspended, or waterlogged woody materials moved bya stream flow.
The discharge that a structure is designed to accommodatewithout exceeding the chosen design constraints. A quantity offlow that is expected at a certain point as a result of a design stormor flood frequency.
The peak discharge (when appropriate, the volume, stage, orwave crest elevation) of the flood associated with the probabilityof exceedence selected for the design of a highwayencroachment.
The recurrence interval for hydrologic events used for designpurposes. As an example, a design frequency of 50 years meansa storm of a given magnitude has a 2 percent (1/50) chance ofbeing equaled or exceeded in one year.
The length of time a structure is designed to function without majorrepairs or replacement.
A precipitation event, with a specified probability of occurring inany given year expressed in years or percentage, used as adesign parameter. May also be a particular storm that contributesa design runoff, depth, duration, or frequency.
corrugated metal pipe (CMP)
cost effective
critical depth
critical flow
critical slope
critical velocity
culvert
debris
design discharge
design flood
design frequency
design life
design storm
21
Inside diameter, measured between inside crests of corrugations.
The volumetric rate of movement or flux of a quantity of waterflowing from a drainage structure or past a given point per unit oftime. Also, flow rate.
Resources or facilities of value or importance that could bepotentially affected by crossing failure.
The line that represents the total amount of energy available atany point along a culvert. Where water is motionless, the watersurface would correspond to the energy grade line. It is establishedby adding together the potential energy expressed as the watersurface elevation referenced to a datum and the kinetic energy,usually expressed as velocity head, at points along the stream bedor culvert profile.
The sum of the hydraulic grade line at any section plus the velocityhead of the mean velocity of the water in that section.
The head lost in eddies and friction at the inlet to a culvert. Also,contraction loss.
Methodology for determining the likelihood of modification by toone or more values.
A steeply inclined channel length in or immediately upstream froma culvert inlet; designed to improve culvert capacity.
Movement of fish through a fishway or culvert.
Exceedence interval, recurrence interval or return period. Theaverage time interval between occurrences of a hydrological eventof a given or greater magnitude. The percent chance ofoccurrence is the reciprocal of flood frequency, e.g., a 2 percentchance of occurrence is the reciprocal statement of a 50-year floodevent.
The volume of water flowing from a drainage structure per unit oftime.
Cross-sectional area of flow calculated on the basis of insideculvert diameter.
Graph showing the percentage of time mean daily discharges havebeen equaled or exceeded.
Elevation at the lowest point in a channel or culvert cross section.
Flow classification based on Froude number, i.e., supercritical orsubcritical.
diameter (D)
discharge
endpoints
energy grade line (EGL)
energy head
entrance loss
environmental risk assessment
fall
fish passage
flood frequency
flow rate
flow area
flow duration curve
flow line elevation
flow regime
he
22
The height from a design water level to the top of a roadway orembankment.
For a rectangular or very wide channels, F = V/(gyh)0.5 where F is
the Froude number; a dimensions number used to determine flowregime. V is the average velocity of flow, g is gravitationalacceleration, and y
h is the hydraulic depth. If F > 1.0, the flow is
supercritical and is characterized as swift, if F< 1.0, the flow issubcritical and is characterized as smooth and tranquil, and if F =1.0, the flow is said to be critical.
The rate of rise or fall of a length of a line or culvert as determinedby the ratio of the change in elevation to the length. Expressedas a percentage or a decimal
Nonuniform flow where the depth of flow changes slowly withdistance. Resistance to flow dominates and acceleration forcesare negligible.
The height of water above any datum.
The retaining wall at an inlet or outlet (usually aligned at rightangles to the culvert but can be skewed).
The height of water at the inlet of a culvert. Usually expressed asthe water height relative to the diameter of the culvert, HW/D. Forexample, if water at the inlet is twice the height of the culvertdiameter, the headwater to culvert diameter ratio is 2.
The water surface elevation upstream from a culvert entranceinvert, measured from a datum. Note: datum may differ betweensoftware applications; measured from culvert invert or anotherdatum.
Distance from crown of culvert to road surface.
Corrugated metal pipe with a continuous helical seam, either lockor welded. Has decreased roughness within the barrel comparedto annular rib corrugations (lower Manning’s n value).
The maximum flow of water that a culvert can continuously pass.
The ratio of the flow area to the top width.
The hydraulic capacity that a culvert is designed to accomodate.
A line representing the total potential energy; a combination ofenergy from the height of the water and internal pressure. In anopen channel, this corresponds to the water surface.
A sudden transition from supercritical flow to subcritical flow, whichis caused by a higher downstream depth, producing a rise in watersurface elevation.
freeboard
Froude number
gradient
gradually varied flow
head (static)
headwall
headwater elevation
height of cover
helical CMP
hydraulic depth
hydraulic jump
headwater
hydraulic capacity
hydraulic grade line (HGL)
hydraulic design
23
The ratio of flow area to wetted perimeter.
A graph of stage, discharge, velocity, runoff, or inflow over time.
The upstream entrance of a culvert.
Culvert flow capacity determined by inlet shape characteristicsand headwater depth.
The uppermost outside point on a cross section of a culvert.
The flowline at the inside lowest point of a culvert cross section.
Culverts that are designed on structural aspects rather thanhydraulic considerations. Usually constructed of structural plate.
Frequency of inspection, routine cleaning, and repair.
An empirical equation used to estimate friction loss and dischargein culvert design. Incorporates channel roughness, hydraulicradius, and cross-sectional area of flow. Assumes uniform flowor gradually varied flow.
An empirical coefficient relating the effect of channel boundaryor culvert roughness to energy losses in flowing water.
Depth of water at normal flow, where discharge, velocity, anddepth do not change with length.
The downstream end of a culvert; the outfall.
Culvert flow capacity determined by the barrel roughness, length,slope, and tailwater elevation.
A plot of culvert discharge versus inlet headwater elevation ordepth.
A corrugated metal pipe shaped to a span (width) greater thanrise (height), structurally continuous, usually prefabricated.
A culvert inlet or outlet that projects from the face of the fill orembankment. Also called a perched or shotgun culvert.
Nonuniform flow where depth of flow changes rapidly over arelatively short distance, such as a hydraulic jump.
A curve that correlates flow rates to flow depths in a channel orculvert.
An approach to estimate the rate of storm runoff based on anintensity-runoff relationship; Q=CIA. C is the coefficient describingrunoff potential of an area, I is the rainfall intensity during the coretime of concentration, and A is the drainage or watershed area.
inlet/outlet crown
invert
long span culverts
maintenance cycle
Manning equation
Manning’s n
normal depth
outlet
outlet control
performance curve
pipe arch
projecting end
rapidly varied flow
rating curve
rational method
hydraulic radius
hydrograph
inlet
inlet control
24
The average period of time expected to elapsebetween successive storm event occurrences of agiven size or larger. It is not a statistical guarantee thata damaging storm will appear on schedule, rather, it isthe reciprocal statement of probability (p): T
r = 1/p.
The maximum vertical height inside a culvert, usuallymeasured at the center line.
Assessing the probability of failure and values at stakefor alternate culvert designs.
The part of precipitation and snowmelt that reachesstreams and eventually the sea by overland andsubsurface flow. This is the stream flow before it isaffected by artificial diversion, impoundments, or othermanmade changes in or on stream channels.
Degradation of the channel at the culvert outlet as aresult of erosive velocities.
The acute angle formed by the intersection of the linenormal to the centerline of the road with the centerlineof a culvert. Also, the angle formed between thecenterline of the culvert and the channel thalweg.
(1) The gradient of a stream; (2) Inclination of the faceof an embankment, expressed as the ratio of thehorizontal to vertical projection; (3) the face of aninclined embankment or cut slope. Expressed as apercent or decimal.
Water surface profiles classified according to channelslope type (mild, steep, critical, horizontal, or adverse).
Discharge, velocity and depth of flow constant throughtime.
Flow at velocities less than critical, with a Froudenumber less than 1. Gravity forces are morepronounced than inertial forces. Flow has a lowervelocity and is often described as steady, tranquil, orstreaming.
Flow at velocities greater than critical, with a Froudenumber greater than 1. Inertial forces are dominant,so the flow has a higher velocity and is usuallydescribed as rapid or shooting.
return period (Tr)
rise
risk analysis
runoff
scour
skew
slope
slope type
steady flow
subcritical flow
supercritical flow
25
First letter of the type of slope (M, S, C, H, or A)combined with the actual depth of flow in relationto the critical and normal depths (Zone 1: actualflow depth is greater than both normal and criticaldepths; Zone 2: flow depth is between the normaland critical depths; or, Zone 3: flow depth is lessthan both normal and critical depths). An exampleis S2.
Depth of water immediately downstream from aculvert, measured from the culvert outlet invert.
Depth of water immediately downstream from aculvert, measured from a datum.
The time required for storm runoff to flow from themost remote point of a drainage area to the pointof consideration. It is usually associated with adesign storm.
Chord describing free surface extent of water in aculvert.
Drag or shear that is developed on the wetted areaof a channel by erode material. Acts in the directionof flow, related to scour.
Depth of flow not varying with distance, implied thatflow is also steady.
Discharge, velocity and depth of flow changing withtime.
Measurement from culvert invert, pool or channelbottom to water surface.
A profile plot of water surface elevation through aculvert or open channel.
The cross-sectional length of wetted contactbetween the water prism and the culvert, measuredat right angles to the culvert.
The retaining walls that provide a transition fromthe culvert headwall to the channel.
surface profile type
tailwater depth
tailwater elevation
time of concentration
topwidth
tractive force
uniform flow
unsteady flow
water depth
water surface profile
wetted perimeter
wingwalls
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