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Drainage Manual Chapters 6 & 7

Chapter 6

Introduction, Surveys, Flood Hazards, Coordination, Documentation, Evaluation of Runoff Factors, Flood History, Hydrologic Method, Design Discharge, Approved Methods,

Design Frequency, Economics, Review Frequency


Introduction, Definition, Factors Affecting Floods, Sources of Information

Symbols And Definitions 
Hydrologic Analysis Procedure Flowchart 
Concept Definitions
Design Frequency

Frequency Table, Rainfall vs. Flood Frequency, Rainfall Curves, Discharge Determination

Hydrologic Procedure Selection

Peak Flow Rates or Hydrographs, Hydrologic Procedures


Definition, Hydrologic Accuracy, Calibration Process

Rational Method

Introduction, Application, Characteristics, Equation, Infrequent Storm, Procedures

Analysis of Stream Gage Data

Introduction, Application, Graphical Method Procedure, Statistical Method Procedure, Skew

Transferring Gaged Data

Procedure, Transfer Equation

USGS Regression Equations - Rural Areas (English Units)

Limits, Calibration, Year Flood

USGS Regression Equations - Adjustment for Basin Urbanization


Computer Programs for Hydrologic Modeling

HEC-1 and TR20, Application, Description, Schematic, Documentation

Hydrology for Temporary Facilities

Detour and Temporary Roadways, Haul Roads, Other Hydraulic Facilities

Average Daily and Spring Flows

Average Daily and Spring Flows

Appendix A - Design Frequencies

Appendix B - Precipitation Frequency Estimates For Connecticut

Appendix C - Travel Time Estimation

Time Of Concentration, Travel Time, Sheet-Flow Travel Time, Shallow Concentrated Flow Travel Time, Open Channel Flow Travel Time, Reservoir or Lake Flow Travel Time, Limitations

Appendix D - Hydrologic Design Report Format

Submittal, Hydrologic Design Report

Appendix E - Major Flood Events in Connecticut Since 1927
Appendix F - Design Procedure: Hydrology for Temporary Facilities 
Chapter 7  

Introduction, Purpose, Definitions, Significance

ConnDOT Design Practices

General, ConnDEP Requirements

Design Criteria

General, Roadside Channels (Type A), Natural Channels (Type B)

Open Channel Flow

General, Specific Energy, Velocity Distribution Coefficient, Total Energy Head, Steady and Unsteady Flow, Uniform Flow and Nonuniform Flow, Gradually-Varied and Rapidly Varied, Froude Number, Critical Flow, Flow Classification, Equation

Stream Morphology

Introduction, Levels of Assessment, Factors That Affect Stream Stability, Stream Response to Change, Countermeasures

Roadside Channels (Type A) Design Procedure

General Design Considerations, Vertical Alignment, Horizontal Alignment, Swales, Interceptor Channels, Type A Channel Design Concepts, Erosion Control Matting 

Hydraulic Analysis (Type B Channels)

General, Cross Sections,  Step-Backwater Models Methodology, Water Surface Profile Computation, Water Surface Profile Computation Procedure, Design Procedure for Natural Channels (Type B), Documentation

Bank Protection (Type B Channels)

Purpose, Erosion Potential, Symbols and Definitions, Design Criteria, Bank and Lining Failure Modes, Revetment Types, Flow Resistance

Design Guidelines - Rock Riprap

Rock Riprap, Bank Slope, Rock Size, Particle Erosion, Steep Slopes, Bridge Piers, Ice Damage, Rock Gradation, Layer Thickness

Appendix A - Simplified Methods for Estimating Wave Height
Appendix B -Vegetative (Grass) Swales and Erosion Control Matting