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Drainage Manual Chapters 8 thru 10

Appendix D - Tapered Inlet Design Form
Chapter 8


Introduction, Purpose, Concepts, Symbols

Design Practices

ConnDOT, ConnDEP Requirement 

Design Criteria

Structural Alternatives, Bridge or Culvert, Allowable Headwater, Review Headwater, Tailwater Relationship-Channel, Tailwater Relationship-Confluence with a Main Stream or Large Water Body, Minimum Culvert Size, Maximum Velocity, Minimum Velocity, Storage-Temporary or Permanent, Flood Frequency, Documentation

Design Features

Culvert Sizes and Shape, Multiple Barrels, Material Selection, Culvert Skew, End Treatment (Inlet or Outlet)

Related Designs

Buoyancy Protection, Outlet Protection, Relief Opening, Erosion And Sediment Control, Environmental Considerations And Fishery Protection, Design Philosophy, Performance Curves

Design Equations

General, Approach, Inlet Control, Outlet Control, Hydraulics (Outlet Control), Outlet Velocity

Erosion,  Sedimentation,  and Debris Control

Introduction, Scour at Inlets, Scour at Outlets, Sedimentation, Assessment of Erosion Potential

Roadway Overtopping

General, Length, Total Flow

Performance Curves

Inlet, Outlet, Roadway, Overall

Design Procedure

Flood Routing Culvert Design

Introduction, Routing Equations, Design Procedure

Tapered Inlets

General, Side-tapered, Slope-tapered Inlets, Hydraulic Design, Design Methods

Appendix A - Recommended Manning's n Values
Appendix B - Entrance Loss Coefficients (Outlet Control,  Full or Partly Full)
Appendix C - Culvert Design Form
Appendix E - Mitered Inlet Design Form
Appendix F - Field Investigation Form
Appendix G - Culvert Design Data Form
Chapter 9

Introduction, Purpose of Chapter, Structural Alternatives, Bridge or Culvert

Design Practices

ConnDOT Design Practices, ConnDOT Practice-Substructures for Bridges over Waterways, ConnDEP Requirements, Flood Management Definitions

Design Criteria

AASHTO General Criteria, ConnDOT General Criteria, Minor Structures, Small Structures, Intermediate Structures, Large Structures, Monumental Structures, Tidal Structures, Documentation

Design Procedure

Survey Accuracy (Computation Method), 

Design Procedure Outline, 

Hydraulic Performance of Bridges, 


Coastal or Tidally Influenced Waterways

Bridge Scour or Aggradation

Introduction, General Discussion ConnDOT Bridges, Data Available Through ConnDOT Scour Program, Scour Types, Engineering Judgement-A discussion of predicted local scour depths at abutments in Connecticut, Armoring, Scour Resistant Materials, Scour Evaluation Studies for ConnDOT Projects


Introduction, Location of Stream Crossing, Coordination,  Permits,  Approvals, Environmental Considerations, Stream Morphology, Data Collection, Risk Evaluation, Scour, Preventive/Protection Measures,  Deck Drainage, Construction/Maintenance 

Appendix A - Forms (Field Investigation and Hydraulic Data)
Appendix B - Amended Local Abutment Scour Equations for Connecticut
Appendix C - Bridge Scour Evaluation Report Format 
Chapter 10
Storage Facilities Introduction, Overview, Location Considerations, Detention And Retention, Computer Programs
Uses Introduction, Quality, Quantity, Objectives, Downstream Effects
Symbols And Definitions
Design Criteria General Criteria, Release Rate, Storage, Grading And Depth, Outlet Works, Location
Safe Dams Act Background, Classification, New Dams, Planning Considerations
Preliminary Computations Data Required, Estimating Required Storage, Hydrograph Method, Triangular Hydrograph Method, NRCS Procedure, Regression Equation,  Estimating Peak Flow Reduction
Stage-Storage Relationship
General, Rectangular Basins, Trapezoidal Basins, Pipes and Conduits, Natural Basins
Outlet Hydraulics General, Orifices, Weirs, Weirs (cont.), Discharge Pipes, Emergency Spillway,  Composite Stage Discharge Curves
Routing Procedure
Temporary Sediment Basin
Dry Pond (Detention Basin) Introduction, Design
Wet Pond (Retention Basin) Introduction, Design 
Infiltration Controls Introduction, Site Selection, Infiltration Trench, Infiltration Basin
Land-Locked Retention Introduction,  Mass Routing
Construction And Maintenance Considerations
Protective Treatment-Fencing